ABOUT THE SPEAKER
Bonnie Bassler - Molecular biologist
Bonnie Bassler studies how bacteria can communicate with one another, through chemical signals, to act as a unit. Her work could pave the way for new, more potent medicine.

Why you should listen

In 2002, bearing her microscope on a microbe that lives in the gut of fish, Bonnie Bassler isolated an elusive molecule called AI-2, and uncovered the mechanism behind mysterious behavior called quorum sensing -- or bacterial communication. She showed that bacterial chatter is hardly exceptional or anomolous behavior, as was once thought -- and in fact, most bacteria do it, and most do it all the time. (She calls the signaling molecules "bacterial Esperanto.")

The discovery shows how cell populations use chemical powwows to stage attacks, evade immune systems and forge slimy defenses called biofilms. For that, she's won a MacArthur "genius" grant -- and is giving new hope to frustrated pharmacos seeking new weapons against drug-resistant superbugs.

Bassler teaches molecular biology at Princeton, where she continues her years-long study of V. harveyi, one such social microbe that is mainly responsible for glow-in-the-dark sushi. She also teaches aerobics at the YMCA.

More profile about the speaker
Bonnie Bassler | Speaker | TED.com
TED2009

Bonnie Bassler: How bacteria "talk"

Bonnie Bassler: Como "falan" as bacterias

Filmed:
2,683,171 views

Bonnie Bassler descubriu que as bacterias "falan" entre elas, usando unha lenguaxe química que lles permite coordinar a súa defensa e os seus ataques. O achado tivo incribles implicacións para a mediciña, industria-- e sobre o coñecemento de nos mesmos
- Molecular biologist
Bonnie Bassler studies how bacteria can communicate with one another, through chemical signals, to act as a unit. Her work could pave the way for new, more potent medicine. Full bio

Double-click the English transcript below to play the video.

00:18
Bacteria are the oldest living organisms on the earth.
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As bacterias son os organismos
máis antigos que viven na Terra.
00:21
They've been here for billions of years,
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Levan aquí miles de millóns de anos
00:23
and what they are are single-celled microscopic organisms.
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sendo organismos microscópicos
unicelulares.
00:27
So they are one cell and they have this special property
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Cada bacteria é unha única célula
coa propiedade especial
00:30
that they only have one piece of DNA.
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de ter soamente un fragmento de ADN
00:32
They have very few genes,
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Teñen moi poucos xenes,
00:34
and genetic information to encode all of the traits that they carry out.
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e esta información xénica codifica
todas as súas funcións.
00:38
And the way bacteria make a living
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As bacterias viven do seguinte xeito:
00:40
is that they consume nutrients from the environment,
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consomen nutrientes do medio,
00:43
they grow to twice their size, they cut themselves down in the middle,
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crecen dobrando o seu tamaño,
córtanse pola metade,
00:46
and one cell becomes two, and so on and so on.
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unha célula convértese en dúas,
e así unha e outra vez.
00:49
They just grow and divide, and grow and divide -- so a kind of boring life,
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Crecen e divídense, crecen e divídense
--é unha vida aburrida--
00:53
except that what I would argue is that you have
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excepto porque vostedes teñen
00:55
an amazing interaction with these critters.
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unhas interaccións incribles
con estes bichos.
00:58
I know you guys think of yourself as humans, and this is sort of how I think of you.
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Vós védesvos como humanos, e
en parte é o que penso de vós.
01:01
This man is supposed to represent
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Este home representa supostamente
01:03
a generic human being,
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un ser humano tipo,
01:05
and all of the circles in that man are all of the cells that make up your body.
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e cada círculo nel
é unha célula que forma o seu corpo.
01:09
There is about a trillion human cells that make each one of us
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Hai arredor dun billón de células humanas
que fan de nós
01:12
who we are and able to do all the things that we do,
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quen somos e permítennos facer o
que facemos,
01:15
but you have 10 trillion bacterial cells
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pero vostedes teñen 10 billóns
de células bacterianas
dentro ou encima,
en calquera intre da súa vida.
01:18
in you or on you at any moment in your life.
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01:20
So, 10 times more bacterial cells
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Hai 10 veces máis células bacterianas
01:22
than human cells on a human being.
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que células humanas nun ser humano.
01:25
And of course it's the DNA that counts,
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E por suposto é o ADN o que conta,
01:27
so here's all the A, T, Gs and Cs
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aquí temos todos os A, T, G e C
01:29
that make up your genetic code, and give you all your charming characteristics.
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que forman os xenes, responsables
das súas peculiaridades.
01:32
You have about 30,000 genes.
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Vostedes teñen sobre 30.000 xenes.
01:34
Well it turns out you have 100 times more bacterial genes
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Ben, pois teñen 100 veces máis
xenes bacterianos
01:37
playing a role in you or on you all of your life.
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que xogan un papel en ou sobre vostedes
durante toda a vida.
01:41
At the best, you're 10 percent human,
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No mellor dos casos, son un 10% humanos,
01:44
but more likely about one percent human,
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pero máis probablemente só un 1%,
01:46
depending on which of these metrics you like.
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dependendo do parámetro que prefiran.
01:48
I know you think of yourself as human beings,
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Sei que se consideran seres humanos,
01:50
but I think of you as 90 or 99 percent bacterial.
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pero eu penso en vostedes
como en bacterias nun 90 ou 99%.
01:54
(Laughter)
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(Risas)
01:55
These bacteria are not passive riders,
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Estas bacterias non son
pasaxeiros pasivos,
01:58
these are incredibly important, they keep us alive.
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son moi importantes,
mantéñennos vivos.
02:01
They cover us in an invisible body armor
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Cóbrennos cunha armadura invisible
02:04
that keeps environmental insults out
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que nos protexe do contorno
02:06
so that we stay healthy.
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manténdonos así sans.
02:08
They digest our food, they make our vitamins,
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Dixiren a nosa comida,
producen vitaminas,
02:10
they actually educate your immune system
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educan o noso sistema inmune
02:12
to keep bad microbes out.
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para impedir a entrada
dos microbios nocivos.
02:14
So they do all these amazing things
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Fan todas estas cousas incribles
02:16
that help us and are vital for keeping us alive,
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que nos axudan e son vitais
para manternos vivos,
02:20
and they never get any press for that.
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e nunca nos acordamos delas por iso.
02:22
But they get a lot of press because they do a lot of
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Pero si que nos acordamos por facer
02:24
terrible things as well.
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cousas terribles.
02:26
So, there's all kinds of bacteria on the Earth
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Sobre a Terra existen
moitos tipos de bacterias
02:29
that have no business being in you or on you at any time,
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que mellor que non estean nunca
en ou sobre vostedes,
02:32
and if they are, they make you incredibly sick.
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pois se están, poñeríanse moi enfermos.
02:36
And so, the question for my lab is whether you want to think about all the
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Por isto, a pregunta no meu laboratorio
non é pensar
02:39
good things that bacteria do, or all the bad things that bacteria do.
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en todas as cousas boas ou malas
que as bacterias fan.
A pregunta que nos formulamos é
como poden facer algo?
02:43
The question we had is how could they do anything at all?
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02:45
I mean they're incredibly small,
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Quero dicir: son incriblemente pequenas,
02:47
you have to have a microscope to see one.
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necesítase un microscopio para velas.
02:49
They live this sort of boring life where they grow and divide,
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Viven esta vida aburrida onde
só crecen e se dividen
02:52
and they've always been considered to be these asocial reclusive organisms.
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e sempre foron consideradas
organismos asociais e solitarios.
02:57
And so it seemed to us that they are just too small to have an impact
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Ademais parécenos que son
pequenas de máis
03:00
on the environment
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para influír sobre o medio
03:02
if they simply act as individuals.
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se actúan unicamente como individuos.
03:04
And so we wanted to think if there couldn't be a different
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E así, demos en pensar se podería ser
03:06
way that bacteria live.
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que as bacterias vivisen de forma distinta
03:08
The clue to this came from another marine bacterium,
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A clave para isto veu
doutra bacteria mariña,
03:12
and it's a bacterium called Vibrio fischeri.
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chamada Vibrio fischeri.
03:15
What you're looking at on this slide is just a person from my lab
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O que vedes nesta diapositiva é
unha persoa do meu laboratorio
03:18
holding a flask of a liquid culture of a bacterium,
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termando dun matraz co cultivo
líquido da bacteria,
03:21
a harmless beautiful bacterium that comes from the ocean,
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esta inofensiva e fermosa bacteria
procede do océano,
03:24
named Vibrio fischeri.
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chámase Vibrio fischeri.
03:26
This bacterium has the special property that it makes light,
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E ten a propiedade especial
de que produce luz,
03:29
so it makes bioluminescence,
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produce bioluminiscencia,
03:31
like fireflies make light.
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igual ca os vagalumes.
03:33
We're not doing anything to the cells here.
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Non lles estamos a facer nada ás células.
03:35
We just took the picture by turning the lights off in the room,
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Só tiramos a foto
coas luces apagadas,
03:37
and this is what we see.
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e velaí o que se ve.
03:39
What was actually interesting to us
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O que é realmente interesante para nós
03:41
was not that the bacteria made light,
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non é que as bacterias produzan luz,
03:43
but when the bacteria made light.
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senón cando a producen.
03:45
What we noticed is when the bacteria were alone,
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Detectamos que cando
as bacterias están soas
03:48
so when they were in dilute suspension, they made no light.
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é dicir, cando están
nunha suspensión diluída , non fan luz.
03:51
But when they grew to a certain cell number
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Pero ao acadaren un certo número
03:53
all the bacteria turned on light simultaneously.
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todas elas "acéndense" á vez.
03:57
The question that we had is how can bacteria, these primitive organisms,
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E preguntámonos como as bacterias,
estes organismos primitivos,
04:01
tell the difference from times when they're alone,
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saben cando están soas,
04:03
and times when they're in a community,
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e cando se atopan en comunidade,
04:05
and then all do something together.
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e entón comezan a facer algo xuntas.
04:08
What we've figured out is that the way that they do that is that they talk to each other,
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O que descubrimos é que fan
todo isto falando unhas coas outras,
04:12
and they talk with a chemical language.
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e que falan usando unha linguaxe química.
04:14
This is now supposed to be my bacterial cell.
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Supoñamos que isto é
a miña célula bacteriana.
04:17
When it's alone it doesn't make any light.
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Cando está soa non fai luz.
04:20
But what it does do is to make and secrete small molecules
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pero si produce e segrega
unhas pequenas moléculas
04:24
that you can think of like hormones,
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que actúan como as hormonas
(son estes triángulos vermellos),
04:26
and these are the red triangles, and when the bacteria is alone
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e cando a bacteria está soa
04:29
the molecules just float away and so no light.
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as moléculas só flotan e non hai luz.
04:32
But when the bacteria grow and double
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Pero cando as bacteria aumentan
04:34
and they're all participating in making these molecules,
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e todas producen estas moléculas,
04:37
the molecule -- the extracellular amount of that molecule
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a molécula
(a cantidade extracelular dela)
04:41
increases in proportion to cell number.
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aumenta proporcionalmente
ao número de células.
04:44
And when the molecule hits a certain amount
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E cando a molécula chega
a unha certa cantidade
04:46
that tells the bacteria how many neighbors there are,
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que lle indica ás bacterias
cantas veciñas están aí,
04:49
they recognize that molecule
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elas recoñecen a molécula
04:51
and all of the bacteria turn on light in synchrony.
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e todas producen luz en sincronía.
04:54
That's how bioluminescence works --
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Así funciona a bioluminiscencia,
04:56
they're talking with these chemical words.
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elas falan con palabras químicas.
04:58
The reason that Vibrio fischeri is doing that comes from the biology.
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A razón pola que Vibrio fischeri
o fai procede da bioloxía.
05:02
Again, another plug for the animals in the ocean,
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Máis publicidade
para os animais do océano,
05:05
Vibrio fischeri lives in this squid.
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Vibrio fischeri vive dentro desta lura.
05:08
What you are looking at is the Hawaiian Bobtail Squid,
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Velaquí a lura hawaiana de rabo curto,
05:10
and it's been turned on its back,
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que está virado de costas,
05:12
and what I hope you can see are these two glowing lobes
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e espero que poidades ver estes
dous lóbulos relucentes
05:15
and these house the Vibrio fischeri cells,
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que acollen as células
de Vibrio fischeri,
05:18
they live in there, at high cell number
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elas viven aí,
a molécula atópase aí,
e están producindo luz.
05:20
that molecule is there, and they're making light.
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05:22
The reason the squid is willing to put up with these shenanigans
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A razón pola que a lura
está disposta a aturar estes diaños
05:25
is because it wants that light.
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é porque quere esa luz.
05:27
The way that this symbiosis works
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A simbiose funciona así:
05:29
is that this little squid lives just off the coast of Hawaii,
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a lura vive cerca da costa de Hawai
05:33
just in sort of shallow knee-deep water.
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en augas tranquilas e pouco profundas.
05:35
The squid is nocturnal, so during the day
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É nocturna, polo que durante o día
05:38
it buries itself in the sand and sleeps,
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sotérrase na area e dorme;
05:40
but then at night it has to come out to hunt.
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pero de noite sae de caza.
05:43
On bright nights when there is lots of starlight or moonlight
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Nas noites claras, de luar ou estreladas
05:45
that light can penetrate the depth of the water
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esa luz pode penetrar ata a profundidade
05:48
the squid lives in, since it's just in those couple feet of water.
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onde vive a lura,
apenas un metro de auga.
05:51
What the squid has developed is a shutter
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A lura desenvolveu un obturador
05:54
that can open and close over this specialized light organ housing the bacteria.
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que abre e pecha o órgano luminoso
que acolle as bacterias.
05:58
Then it has detectors on its back
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Ten uns sensores no lombo
06:00
so it can sense how much starlight or moonlight is hitting its back.
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que detectan canta claridade
lle chega a el.
06:04
And it opens and closes the shutter
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O obturador abre ou pecha
06:06
so the amount of light coming out of the bottom --
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de modo que a luz emitida
pola parte inferior
06:08
which is made by the bacterium --
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--que é producida pola bacteria--
06:10
exactly matches how much light hits the squid's back,
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é a mesma que chega ao lombo da lura,
06:12
so the squid doesn't make a shadow.
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e así, a lura non produce sombra.
06:14
It actually uses the light from the bacteria
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De feito, usa a luz das bacterias
06:17
to counter-illuminate itself in an anti-predation device
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para contrailuminarse como
un mecanismo antipredación
06:20
so predators can't see its shadow,
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xa que os predadores
non poden ver a súa sombra,
06:22
calculate its trajectory, and eat it.
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calcular a súa traxectoria, e comela.
06:24
This is like the stealth bomber of the ocean.
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Como se fose o bombardeiro
furtivo do océano.
06:27
(Laughter)
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(Risas)
06:28
But then if you think about it, the squid has this terrible problem
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Pero se pensades nisto,
a lura ten un terrible problema
06:31
because it's got this dying, thick culture of bacteria
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porque ten un gran cultivo
de bacterias moribundas
06:34
and it can't sustain that.
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que non pode manter continuamente.
06:36
And so what happens is every morning when the sun comes up
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O que fai é que, cada maña cando sae o sol
06:38
the squid goes back to sleep, it buries itself in the sand,
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a lura volve durmir,
sotérrase na area,
06:41
and it's got a pump that's attached to its circadian rhythm,
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e ten unha bomba ligada
ao seu ritmo circadiano,
06:44
and when the sun comes up it pumps out like 95 percent of the bacteria.
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e cando alborece expele
o 95% das bacterias.
06:49
Now the bacteria are dilute, that little hormone molecule is gone,
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Agora as bacterias están diluídas,
non hai moléculas abondas,
06:52
so they're not making light --
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así que elas non producen luz,
06:54
but of course the squid doesn't care. It's asleep in the sand.
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pero á lura élle igual.
Está durmindo na area.
06:56
And as the day goes by the bacteria double,
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Ao longo do día as bacterias duplícanse,
06:58
they release the molecule, and then light comes on
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liberan a molécula, e a luz acéndese
07:01
at night, exactly when the squid wants it.
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de noite, exactamente cando a lura quere.
07:04
First we figured out how this bacterium does this,
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Primeiro descubrimos
como facía isto a bacteria,
07:07
but then we brought the tools of molecular biology to this
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logo empregamos as ferramentas
da bioloxía molecular
para descifrar como é
de verdade o mecanismo.
07:10
to figure out really what's the mechanism.
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07:12
And what we found -- so this is now supposed to be, again, my bacterial cell --
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E o que atopamos --supoñamos
que esta é outra vez a miña bacteria--
07:16
is that Vibrio fischeri has a protein --
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é que Vibrio fischeri ten una proteína
07:18
that's the red box -- it's an enzyme that makes
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--a caixa vermella--,
é un enzima que produce
07:21
that little hormone molecule, the red triangle.
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esa pequena molécula
--o triángulo vermello.
Mentres as células crecen
liberan a molécula
07:24
And then as the cells grow, they're all releasing that molecule
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07:26
into the environment, so there's lots of molecule there.
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ao medio ambiente, polo que
hai moitas moléculas.
07:29
And the bacteria also have a receptor on their cell surface
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E a célula tamén ten un receptor
na súa superficie celular
07:33
that fits like a lock and key with that molecule.
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que encaixa coa molécula coma
unha chave nunha pechadura
07:36
These are just like the receptors on the surfaces of your cells.
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Son xusto coma os receptores
da superficie das vosas células.
07:39
When the molecule increases to a certain amount --
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Cando a molécula aumenta
ata certa cantidade
07:42
which says something about the number of cells --
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--o que ten relación co
número de células--
07:44
it locks down into that receptor
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encaixa no receptor
07:46
and information comes into the cells
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e a información entra nas células
07:48
that tells the cells to turn on
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para dicirlle a estas que activen
07:50
this collective behavior of making light.
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o comportamento colectivo de facer luz.
07:53
Why this is interesting is because in the past decade
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Isto é interesante porque na década pasada
07:56
we have found that this is not just some anomaly
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atopamos que non é unha anomalía
07:58
of this ridiculous, glow-in-the-dark bacterium that lives in the ocean --
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desta ridícula bacteria brillante
que vive no océano:
08:01
all bacteria have systems like this.
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todas as bacterias teñen
sistemas semellantes a esta.
08:04
So now what we understand is that all bacteria can talk to each other.
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Agora entendemos que todas as
bacterias falan unhas con outras.
08:07
They make chemical words, they recognize those words,
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Emiten unhas palabra químicas,
recoñécenas,
08:10
and they turn on group behaviors
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e activan o comportamento grupal
08:12
that are only successful when all of the cells participate in unison.
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que só ten éxito cando
as células cooperan ao unísono.
08:17
We have a fancy name for this: we call it quorum sensing.
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Nós chamámoslle a isto
"percepción do quórum"
08:20
They vote with these chemical votes,
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Elas votan con eses votos químicos,
08:22
the vote gets counted, and then everybody responds to the vote.
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os votos cóntanse, e logo todo
o mundo responde ao resultado.
08:26
What's important for today's talk
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O máis importante da charla de hoxe
08:28
is that we know that there are hundreds of behaviors
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é que sabemos que hai centos de condutas
08:30
that bacteria carry out in these collective fashions.
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que as bacterias executan
de xeito colectivo.
08:33
But the one that's probably the most important to you is virulence.
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Mais, probablemente o máis
importante para vós é a virulencia.
08:36
It's not like a couple bacteria get in you
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Non é que un par de bacterias
entren en vós
08:39
and they start secreting some toxins --
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e comecen a segregar toxinas
08:41
you're enormous, that would have no effect on you. You're huge.
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--vós sodes enormes--
que non vos farían efecto ningún.
O que fan, agora o entendemos,
08:44
What they do, we now understand,
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08:47
is they get in you, they wait, they start growing,
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é entrar en vós, esperar,
empezar a crecer,
08:50
they count themselves with these little molecules,
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recontarse coas moléculas
08:52
and they recognize when they have the right cell number
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e recoñecer cando son o número abondo
08:54
that if all of the bacteria launch their virulence attack together,
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para --se lanzan xuntas
o seu ataque virulento--
08:58
they are going to be successful at overcoming an enormous host.
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teren éxito ao bater
a un enorme anfitrión.
09:02
Bacteria always control pathogenicity with quorum sensing.
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As bacterias sempre controlan a
patoxenicidade coa percepción do quórum
09:06
That's how it works.
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Así funcionan.
09:08
We also then went to look at what are these molecules --
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Tamén observamos que
son estas moléculas
09:11
these were the red triangles on my slides before.
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--estes son os triángulos vermellos
nas miñas diapositivas.
09:14
This is the Vibrio fischeri molecule.
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Esta é a molécula de Vibrio fischeri.
09:16
This is the word that it talks with.
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Esta é a palabra con que se comunica.
09:18
So then we started to look at other bacteria,
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Entón comezamos a observar
outras bacterias,
09:20
and these are just a smattering of the molecules that we've discovered.
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e estas son só unha mostra das
moléculas que atopamos.
09:23
What I hope you can see
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O que espero que poidan ver
09:25
is that the molecules are related.
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é que as moléculas están relacionadas.
09:27
The left-hand part of the molecule is identical
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A parte esquerda da molécula é idéntica
09:29
in every single species of bacteria.
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en todas as especies de bacteria.
09:32
But the right-hand part of the molecule is a little bit different in every single species.
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Mais a parte dereita
é un chisco diferente en cada especie.
09:36
What that does is to confer
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O que lle confire
09:38
exquisite species specificities to these languages.
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unha especificidade exquisita
a estas linguaxes.
09:42
Each molecule fits into its partner receptor and no other.
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Cada molécula encaixa no
seu receptor e non noutro.
09:46
So these are private, secret conversations.
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Polo que estas son
conversacións privadas, secretas.
09:49
These conversations are for intraspecies communication.
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Estas conversacións son para
comunicarse dentro da mesma especie.
09:53
Each bacteria uses a particular molecule that's its language
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Cada bacteria usa a súa molécula
que é a súa linguaxe
09:57
that allows it to count its own siblings.
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que lle permite contar as súas irmás.
10:01
Once we got that far we thought
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Cando chegamos ata aquí pensamos
10:03
we were starting to understand that bacteria have these social behaviors.
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que comezamos a entender
que as bacterias teñen condutas sociais.
10:06
But what we were really thinking about is that most of the time
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Mais o que de verdade pensabamos
é que a maior parte do tempo
10:09
bacteria don't live by themselves, they live in incredible mixtures,
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as bacterias non viven soas,
viven en mesturas incribles,
10:12
with hundreds or thousands of other species of bacteria.
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con centos ou miles doutras
especies de bacterias.
10:16
And that's depicted on this slide. This is your skin.
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É o que se representa nesta diapositiva.
Esta é a súa pel.
10:19
So this is just a picture -- a micrograph of your skin.
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Isto é soamente unha imaxe
--unha micrografía da súa pel.
Calquera lugar do corpo,
parécese moito a isto,
10:22
Anywhere on your body, it looks pretty much like this,
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10:24
and what I hope you can see is that there's all kinds of bacteria there.
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e espero que poidan ver que aí
hai todo tipo de bacterias.
10:28
And so we started to think if this really is about communication in bacteria,
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Entón, comezamos a pensar que se
realmente a comunicación entre bacterias
10:32
and it's about counting your neighbors,
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ten que ver con contar os veciños,
10:34
it's not enough to be able to only talk within your species.
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non abonda con falar
só cos da túa especie.
10:37
There has to be a way to take a census
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Ten que existir un xeito de censar
10:39
of the rest of the bacteria in the population.
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ao resto de bacterias na poboación.
10:42
So we went back to molecular biology
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Polo que volvemos á bioloxía molecular
10:44
and started studying different bacteria,
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e comezamos a estudar
diferentes bacterias,
10:46
and what we've found now is that
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e o que atopamos agora foi que
10:48
in fact, bacteria are multilingual.
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en realidade, as bacterias son políglotas.
10:50
They all have a species-specific system --
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Todas teñen
un sistema específico por especie
10:53
they have a molecule that says "me."
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--unha molécula que di "eu".
10:55
But then, running in parallel to that is a second system
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Pero vai en paralelo a un segundo sistema
10:58
that we've discovered, that's generic.
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que descubrimos, que é xenérico.
11:00
So, they have a second enzyme that makes a second signal
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Elas teñen un segundo enzima
que fai un segundo sinal
11:03
and it has its own receptor,
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e ten o seu propio receptor,
11:05
and this molecule is the trade language of bacteria.
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e esta molécula é
a lingua internacional das bacterias.
11:08
It's used by all different bacteria
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Todas a empregan
11:10
and it's the language of interspecies communication.
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e é a lingua de comunicación
entre especies.
11:14
What happens is that bacteria are able to count
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As bacterias son capaces de contar
11:17
how many of me and how many of you.
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cantos "eu" e cantos "ti" hai.
11:20
They take that information inside,
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Elas recollen esa información,
11:22
and they decide what tasks to carry out
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e deciden que tarefas fan
11:24
depending on who's in the minority and who's in the majority
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dependendo de quen estea en
minoría e quen en maioría
11:28
of any given population.
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dunha poboación determinada.
11:30
Then again we turn to chemistry,
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Outra vez voltamos a química,
11:32
and we figured out what this generic molecule is --
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e atopamos que esta molécula xenérica é
11:35
that was the pink ovals on my last slide, this is it.
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--son os óvalos rosas da miña
última diapositiva--
11:38
It's a very small, five-carbon molecule.
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é moi pequena, unha molécula
de 5 átomos de carbonos.
11:40
What the important thing is that we learned
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O importante é que aprendemos
11:43
is that every bacterium has exactly the same enzyme
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que cada bacteria ten
exactamente o mesmo enzima
11:46
and makes exactly the same molecule.
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e fai exactamente a mesma molécula.
11:48
So they're all using this molecule
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Todas usan esta molécula
11:50
for interspecies communication.
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para comunicarse entre especies.
11:52
This is the bacterial Esperanto.
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Velaquí o esperanto bacteriano.
11:55
(Laughter)
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(Risas)
11:56
Once we got that far, we started to learn
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Chegados ata aquí,
comezamos a comprender
11:58
that bacteria can talk to each other with this chemical language.
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que as bacterias falan entre si
con esta linguaxe química.
12:01
But what we started to think is that maybe there is something
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Pero comezamos a pensar se haberá
12:03
practical that we can do here as well.
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algo práctico que poidamos facer aquí.
12:05
I've told you that bacteria do have all these social behaviors,
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Díxenlles que as bacterias teñen
todas estas condutas sociais,
12:08
they communicate with these molecules.
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que se comunican con estas moléculas.
12:11
Of course, I've also told you that one of the important things they do
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Tamén lles dixen que una das cousas
máis importantes que fan
12:14
is to initiate pathogenicity using quorum sensing.
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é iniciar a patoxenicidade
usando a percepción do quórum.
12:17
We thought, what if we made these bacteria
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Nós pensamos, e se
facemos que as bacterias
12:19
so they can't talk or they can't hear?
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non poidan falar ou escoitar?
12:22
Couldn't these be new kinds of antibiotics?
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Non podería ser
un novo tipo de antibiótico?
12:25
Of course, you've just heard and you already know
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Seguro que xa escoitastes e sabedes
12:27
that we're running out of antibiotics.
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que estamos quedando sen antibióticos.
12:29
Bacteria are incredibly multi-drug-resistant right now,
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Neste momento, as bacterias son
incriblemente resistentes,
12:32
and that's because all of the antibiotics that we use kill bacteria.
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porque os antibióticos que usamos
matan as bacterias.
12:36
They either pop the bacterial membrane,
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Rebentan a membrana bacteriana,
12:38
they make the bacterium so it can't replicate its DNA.
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ou fan que a bacteria non poida
replicar o seu ADN.
12:41
We kill bacteria with traditional antibiotics
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Cos antibióticos tradicionais,
nós matamos as bacterias,
o que selecciona as mutacións resistentes.
12:44
and that selects for resistant mutants.
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12:46
And so now of course we have this global problem
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E así, agora temos este problema global
12:49
in infectious diseases.
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de enfermidades infecciosas.
Nós pensamos: e se puideramos cambiar
dalgún modo o seu comportamento,
12:51
We thought, well what if we could sort of do behavior modifications,
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12:54
just make these bacteria so they can't talk, they can't count,
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facenr que estas bacterias
non poidan falar ou contar,
12:57
and they don't know to launch virulence.
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e así, tampouco producir virulencia?
13:00
And so that's exactly what we've done, and we've sort of taken two strategies.
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E fixemos exactamente iso,
empregando dúas estratexias.
13:03
The first one is we've targeted
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A primeira tivo como obxectivo
13:05
the intraspecies communication system.
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o sistema de comunicación
dentro da mesma especie.
13:08
So we made molecules that look kind of like the real molecules --
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Fixemos moléculas
similares ás moléculas reais
13:11
which you saw -- but they're a little bit different.
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--velaquí as tedes--
mais un chisco distintas.
13:13
And so they lock into those receptors,
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Encaixan nos receptores,
13:15
and they jam recognition of the real thing.
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e bloquean o recoñecemento
da molécula real.
13:18
By targeting the red system,
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Poñendo como obxectivo o sistema vermello
13:20
what we are able to do is to make
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somos capaces de obter
moleculas antipercepción do quórum
13:22
species-specific, or disease-specific, anti-quorum sensing molecules.
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específicas para especies
ou para enfermidades.
13:27
We've also done the same thing with the pink system.
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Tamén fixemos o mesmo co sistema rosa.
13:30
We've taken that universal molecule and turned it around a little bit
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Collemos a molécula universal
e cambiámoslle un fragmento,
13:33
so that we've made antagonists
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co que obtivemos antagonistas
13:35
of the interspecies communication system.
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do sistema de comunicación entre especies.
13:37
The hope is that these will be used as broad-spectrum antibiotics
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A esperanza é que isto poida empregarse
como antibióticos de amplo espectro
13:42
that work against all bacteria.
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que funcionen contra todas as bacterias.
13:44
To finish I'll just show you the strategy.
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Para rematar, déixenme
amosarlles a estratexia.
13:47
In this one I'm just using the interspecies molecule,
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Nesta emprego unha molécula interespecie.
13:49
but the logic is exactly the same.
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pero a lóxica é a mesma.
13:51
What you know is that when that bacterium gets into the animal,
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O que sabemos é que cando unha
bacteria entra nun animal,
13:54
in this case, a mouse,
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neste caso, un rato,
13:56
it doesn't initiate virulence right away.
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non comeza a virulencia inmediatamente.
13:58
It gets in, it starts growing, it starts secreting
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Entra, comeza a medrar, empeza a segregar
14:01
its quorum sensing molecules.
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as moléculas de percepción do quórum.
14:03
It recognizes when it has enough bacteria
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Recoñece cando hai bacterias abondas
14:05
that now they're going to launch their attack,
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e entón lanzan o seu ataque,
14:07
and the animal dies.
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e o animal morre.
14:09
What we've been able to do is to give these virulent infections,
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O que fixemos foi producir
estas infeccións virulentas,
14:12
but we give them in conjunction with our anti-quorum sensing molecules --
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pero engadindo moléculas
antipercepción do quórum
14:16
so these are molecules that look kind of like the real thing,
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--estas moléculas
seméllanse ás reais,
14:18
but they're a little bit different which I've depicted on this slide.
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pero son algo diferentes,
como se ve na diapositiva.
14:21
What we now know is that if we treat the animal
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Agora sabemos que se tratamos o animal
14:24
with a pathogenic bacterium -- a multi-drug-resistant pathogenic bacterium --
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cunha bacteria patóxena
--unha bacteria multirresistente--
14:28
in the same time we give our anti-quorum sensing molecule,
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ao mesmo tempo que lle damos
moléculas antipercepción do quórum,
14:32
in fact, the animal lives.
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de feito, o animal vive.
14:34
We think that this is the next generation of antibiotics
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Nós pensamos que esta é a
próxima xeración de antibióticos
14:38
and it's going to get us around, at least initially,
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e vainos permitir superar,
polo menos inicialmente,
14:40
this big problem of resistance.
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este gran problema da resistencia.
14:42
What I hope you think, is that bacteria can talk to each other,
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O que espero que entendan
é que as bacterias falan entre elas,
14:45
they use chemicals as their words,
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usan substancias químicas como palabras,
14:48
they have an incredibly complicated chemical lexicon
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teñen un léxico químico
incriblemente complexo
14:51
that we're just now starting to learn about.
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que agora estamos comezando a aprender.
14:53
Of course what that allows bacteria to do
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De feito, isto permítelles actuar
14:56
is to be multicellular.
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como se fosen pluricelulares.
14:58
So in the spirit of TED they're doing things together
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Seguindo o espírito de TED
elas fan cousas xuntas
15:01
because it makes a difference.
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porque iso marca a diferenza.
15:03
What happens is that bacteria have these collective behaviors,
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E así, as bacterias
teñen esas condutas colectivas,
15:07
and they can carry out tasks
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e levan a cabo tarefas
15:09
that they could never accomplish
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que nunca poderían facer
15:11
if they simply acted as individuals.
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se actuasen só como individuos.
15:13
What I would hope that I could further argue to you
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O que me gustaría defender
15:16
is that this is the invention of multicellularity.
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é que isto é a invención
de pluricelularidade.
15:19
Bacteria have been on the Earth for billions of years;
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As bacterias levan na Terra
miles de millóns de anos;
15:23
humans, couple hundred thousand.
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os seres humanos, uns douscentos mil.
15:25
We think bacteria made the rules
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Cremos que as bacterias
estableceron as regras
15:27
for how multicellular organization works.
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sobre como funciona a
organización pluricelular.
15:30
We think, by studying bacteria,
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Pensamos que, estudando as bacterias,
15:33
we're going to be able to have insight about multicellularity in the human body.
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coñeceremos máis sobre a
pluricelularidade no corpo humano.
15:37
We know that the principles and the rules,
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Sabemos que, se entendemos
os principios e as regras,
15:39
if we can figure them out in these sort of primitive organisms,
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nestes organismos primitivos,
15:41
the hope is that they will be applied
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é posible que os poidamos aplicar
15:43
to other human diseases and human behaviors as well.
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a outras enfermidades e condutas humanas.
15:47
I hope that what you've learned
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Espero que aprenderan
15:49
is that bacteria can distinguish self from other.
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que as bacterias poden distinguirse
unhas das outras.
15:52
By using these two molecules they can say "me" and they can say "you."
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3000
Usando esas dúas moléculas
poden dicir "eu" ou "ti".
15:55
Again of course that's what we do,
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Unha vez máis, iso é o que facemos,
15:57
both in a molecular way,
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nunha forma molecular,
15:59
and also in an outward way,
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e nunha forma externa,
16:01
but I think about the molecular stuff.
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pero eu interésome pola parte molecular.
16:03
This is exactly what happens in your body.
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Isto é o que pasa no seu corpo.
16:05
It's not like your heart cells and your kidney cells get all mixed up every day,
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As células do corazón e as dos riles
nunca se mesturan,
16:08
and that's because there's all of this chemistry going on,
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grazas a todos estes procesos químicos,
16:11
these molecules that say who each of these groups of cells is,
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a estas moléculas que din
que células son de cada grupo,
16:14
and what their tasks should be.
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e que tarefas debe realizar cada un.
16:16
Again, we think that bacteria invented that,
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Outra vez, cremos que iso
o inventaron as bacterias,
16:19
and you've just evolved a few more bells and whistles,
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e vostedes evolucionaron un pouco máis,
16:22
but all of the ideas are in these simple systems that we can study.
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pero todas as ideas están nestes sistemas
simples que podemos estudar.
16:26
The final thing is, again just to reiterate that there's this practical part,
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Por último, reiterar que isto ten
unha vertente práctica,
16:30
and so we've made these anti-quorum sensing molecules
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e que fixemos estas moléculas
antipercepción do quórum
16:33
that are being developed as new kinds of therapeutics.
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que están sendo desenvolvidas como
novos tipos de terapia.
16:36
But then, to finish with a plug for all the good and miraculous bacteria
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Para rematar un recoñecemento
a todas as boas e incribles bacterias
16:39
that live on the Earth,
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que viven na Terra,
16:41
we've also made pro-quorum sensing molecules.
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que fan moléculas propercepción do quórum.
16:43
So, we've targeted those systems to make the molecules work better.
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Modificamos os sistemas para
facer que as moléculas funcionen mellor.
16:46
Remember you have these 10 times or more bacterial cells
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Lembren que teñen 10 veces
máis células bacterianas
16:50
in you or on you, keeping you healthy.
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en ou sobre vostedes, manténdoos sans.
16:52
What we're also trying to do is to beef up the conversation
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Tamén estamos a tratar de
fortalecer a conversación
16:55
of the bacteria that live as mutualists with you,
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das bacterias que viven
como mutualistas con vostedes,
16:58
in the hopes of making you more healthy,
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coa esperanza de facelos máis sans,
17:00
making those conversations better,
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mellorando esas conversacións,
17:02
so bacteria can do things that we want them to do
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para que as bacterias poidan facer
cousas que nos interesen
17:05
better than they would be on their own.
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mellor do que o farían por si mesmas.
17:08
Finally, I wanted to show you
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Para rematar, quero mostrarlles
17:10
this is my gang at Princeton, New Jersey.
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o meu grupo en Princeton, Nova Jersey.
17:12
Everything I told you about was discovered by someone in that picture.
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Todo o que lles contei descubriuno
alguén desta foto.
17:16
I hope when you learn things,
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Espero que cando aprendan cousas,
17:18
like about how the natural world works --
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por exemplo, como funciona o mundo natural
17:20
I just want to say that whenever you read something in the newspaper
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--cando lea algo no xornal
17:23
or you get to hear some talk about something ridiculous in the natural world
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ou oia algunha conversa sobre
algo ridículo no mundo natural
17:26
it was done by a child.
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pode que o fixese un rapaz.
17:28
Science is done by that demographic.
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A ciencia faina este grupo de idade.
17:30
All of those people are between 20 and 30 years old,
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Todos teñen entre 20 e 30 anos,
17:34
and they are the engine that drives scientific discovery in this country.
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e son o motor que move
os descubrimentos científicos neste país.
17:38
It's a really lucky demographic to work with.
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É unha sorte traballar con eles.
17:41
I keep getting older and older and they're always the same age,
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Eu son cada vez máis vella e eles
sempre teñen a mesma idade,
17:44
and it's just a crazy delightful job.
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e é simplemente
un traballo tolo e esgotador.
17:47
I want to thank you for inviting me here.
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Quero darlles as grazas por invitarme.
17:49
It's a big treat for me to get to come to this conference.
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É un gran pracer para min
asistir a esta conferencia
17:52
(Applause)
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(Aplausos)
17:57
Thanks.
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Grazas.
17:58
(Applause)
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(Aplausos)
Translated by Andrea Muras
Reviewed by Xusto Rodriguez

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ABOUT THE SPEAKER
Bonnie Bassler - Molecular biologist
Bonnie Bassler studies how bacteria can communicate with one another, through chemical signals, to act as a unit. Her work could pave the way for new, more potent medicine.

Why you should listen

In 2002, bearing her microscope on a microbe that lives in the gut of fish, Bonnie Bassler isolated an elusive molecule called AI-2, and uncovered the mechanism behind mysterious behavior called quorum sensing -- or bacterial communication. She showed that bacterial chatter is hardly exceptional or anomolous behavior, as was once thought -- and in fact, most bacteria do it, and most do it all the time. (She calls the signaling molecules "bacterial Esperanto.")

The discovery shows how cell populations use chemical powwows to stage attacks, evade immune systems and forge slimy defenses called biofilms. For that, she's won a MacArthur "genius" grant -- and is giving new hope to frustrated pharmacos seeking new weapons against drug-resistant superbugs.

Bassler teaches molecular biology at Princeton, where she continues her years-long study of V. harveyi, one such social microbe that is mainly responsible for glow-in-the-dark sushi. She also teaches aerobics at the YMCA.

More profile about the speaker
Bonnie Bassler | Speaker | TED.com
THE ORIGINAL VIDEO ON TED.COM