TED2009
Bonnie Bassler: How bacteria "talk"
Bonnie Bassler o sporazumevanju bakterij
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Bonnie Bassler govori o odkritju, da se bakterije med seboj sporazumevajo s kemično govorico, ki sproži skupinsko obrambo ali napad. To spoznanje ima pomembno vlogo v medicini, industriji in dojemanju nas samih.
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. Full bio
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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Bakterije so najstarejši živeči organizmi na Zemlji.
00:21
They've been here for billions of years,
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Ti enocelični mikroskopski organizmi
00:23
and what they are are single-celled microscopic organisms.
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obstajajo že miljarde let.
00:27
So they are one cell and they have this special property
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Gre torej za enoceličarje, njihova značilnost pa je,
00:30
that they only have one piece of DNA.
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da imajo enojen genski zapis.
00:32
They have very few genes,
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Imajo zelo malo genov,
00:34
and genetic information to encode all of the traits that they carry out.
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genski zapis vsebuje vse njihove značilnosti.
00:38
And the way bacteria make a living
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Bakterije se preživljajo
00:40
is that they consume nutrients from the environment,
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s hranili iz okolja,
00:43
they grow to twice their size, they cut themselves down in the middle,
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zrastejo in se prepolovijo,
00:46
and one cell becomes two, and so on and so on.
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s čimer nastaneta dve novi celici in tako dalje.
00:49
They just grow and divide, and grow and divide -- so a kind of boring life,
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Stalno rastejo in se delijo -- nič posebnega --
00:53
except that what I would argue is that you have
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vendar pa smo s temi bitji
00:55
an amazing interaction with these critters.
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v izjemnem odnosu.
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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Vem, da vi sebe vidite kot ljudi, jaz pa razmišljam tako.
01:01
This man is supposed to represent
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Ta figura predstavlja
01:03
a generic human being,
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povprečnega človeka,
01:05
and all of the circles in that man are all of the cells that make up your body.
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pike na njem pa predstavljajo celice, ki sestavljajo človeško telo.
01:09
There is about a trillion human cells that make each one of us
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Vsakega od nas sestavlja okrog bilijon človeških celic
01:12
who we are and able to do all the things that we do,
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zaradi katerih lahko živimo in delujemo,
01:15
but you have 10 trillion bacterial cells
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poleg tega pa je v in na nas še 10 bilijonov bakterijskih celic
01:18
in you or on you at any moment in your life.
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v vsakem trenutku življenja.
01:20
So, 10 times more bacterial cells
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Na človeškem telesu je torej
01:22
than human cells on a human being.
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desetkrat več bakterijskih kot človeških celic.
01:25
And of course it's the DNA that counts,
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Šteje pa seveda le zaporedje nukleotidov
01:27
so here's all the A, T, Gs and Cs
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A, T, G in C,
01:29
that make up your genetic code, and give you all your charming characteristics.
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ki sestavljajo vaš genski kod in pogojujejo vaše značilnosti.
01:32
You have about 30,000 genes.
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Imate okrog 30.000 genov.
01:34
Well it turns out you have 100 times more bacterial genes
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Bakterijskih genov imate stokrat več,
01:37
playing a role in you or on you all of your life.
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za vas pa so pomembni celo življenje.
01:41
At the best, you're 10 percent human,
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Morda ste 10 odstotkov človek,
01:44
but more likely about one percent human,
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verjetneje pa zgolj 1 odstotek,
01:46
depending on which of these metrics you like.
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odvisno kateri vidik vam je ljubši.
01:48
I know you think of yourself as human beings,
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Vi se vidite kot ljudi,
01:50
but I think of you as 90 or 99 percent bacterial.
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jaz pa vas vidim kot skoraj izključno bakterije.
01:54
(Laughter)
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(Smeh)
01:55
These bacteria are not passive riders,
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Te bakterije niso pasivne,
01:58
these are incredibly important, they keep us alive.
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pač pa so izjemnega pomena, saj nas ohranjajo žive.
02:01
They cover us in an invisible body armor
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Okrog nas ustvarjajo neviden ščit,
02:04
that keeps environmental insults out
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ki nas brani pred škodljivimi vplivi okolja,
02:06
so that we stay healthy.
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da ne zbolimo.
02:08
They digest our food, they make our vitamins,
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Prebavljajo nam hrano, sintetizirajo vitamine,
02:10
they actually educate your immune system
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našemu imunskemu sistemu sporočajo,
02:12
to keep bad microbes out.
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naj se ubrani slabih mikrobov.
02:14
So they do all these amazing things
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Vse te neverjetne stvari počnejo,
02:16
that help us and are vital for keeping us alive,
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da ostanemo živi in zdravi,
02:20
and they never get any press for that.
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pa kljub temu ostajajo prezrte.
02:22
But they get a lot of press because they do a lot of
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Ponovno se jih pa zavemo,
02:24
terrible things as well.
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ko smo zaradi njih ogroženi.
02:26
So, there's all kinds of bacteria on the Earth
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Na Zemlji je torej mnogo vrst bakterij,
02:29
that have no business being in you or on you at any time,
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ki niso v stiku s človeškim telesom,
02:32
and if they are, they make you incredibly sick.
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ko pa so, lahko zaradi tega hudo zbolite.
02:36
And so, the question for my lab is whether you want to think about all the
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V našem laboratoriju se torej ukvarjamo s tem,
02:39
good things that bacteria do, or all the bad things that bacteria do.
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ali so pomembnejši dobri ali slabi vplivi bakterij.
02:43
The question we had is how could they do anything at all?
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Zanimalo nas je predvsem, kako sploh lahko kaj naredijo?
02:45
I mean they're incredibly small,
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Ker so izjemno majhne,
02:47
you have to have a microscope to see one.
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jih lahko vidimo le z mikroskopom.
02:49
They live this sort of boring life where they grow and divide,
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Vse življenje le rastejo in se delijo
02:52
and they've always been considered to be these asocial reclusive organisms.
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in vedno se jih je dojemalo kot samotarske organizme.
02:57
And so it seemed to us that they are just too small to have an impact
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Zdelo se nam je, da so pač premajhne,
03:00
on the environment
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da bi lahko vplivale na okolje,
03:02
if they simply act as individuals.
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če delujejo individualno.
03:04
And so we wanted to think if there couldn't be a different
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Zanimalo nas je torej, ali obstaja
03:06
way that bacteria live.
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drugačen način življenja bakterij.
03:08
The clue to this came from another marine bacterium,
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Namig za to nam je dala morska bakterija,
03:12
and it's a bacterium called Vibrio fischeri.
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imenovana Vibrio fischeri.
03:15
What you're looking at on this slide is just a person from my lab
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Na sliki vidite pomočnika iz mojega laboratorija,
03:18
holding a flask of a liquid culture of a bacterium,
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ki drži bučko tekoče bakterijske kulture,
03:21
a harmless beautiful bacterium that comes from the ocean,
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čudovite neškodljive bakterije iz oceana,
03:24
named Vibrio fischeri.
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imenovane Vibrio fischeri.
03:26
This bacterium has the special property that it makes light,
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Njena posebnost je, da ustvarja svetlobo,
03:29
so it makes bioluminescence,
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torej bioluminescenco,
03:31
like fireflies make light.
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tako kot kresnice.
03:33
We're not doing anything to the cells here.
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Tem celicam nismo dodali ničesar.
03:35
We just took the picture by turning the lights off in the room,
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Fotografijo smo posneli le z ugasnjenimi lučmi
03:37
and this is what we see.
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in videlo se je to.
03:39
What was actually interesting to us
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Za nas ni bilo presenetljivo to,
03:41
was not that the bacteria made light,
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da bakterije ustvarjajo svetlobo,
03:43
but when the bacteria made light.
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pač pa kdaj jo ustvarjajo.
03:45
What we noticed is when the bacteria were alone,
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Ugotovili smo, da v osami
03:48
so when they were in dilute suspension, they made no light.
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oz. v razredčeni suspenziji do tega ne pride.
03:51
But when they grew to a certain cell number
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Ko pa se namnožijo do določenega števila celic,
03:53
all the bacteria turned on light simultaneously.
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začnejo vse bakterije hkrati oddajati svetlobo.
03:57
The question that we had is how can bacteria, these primitive organisms,
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Želeli smo vedeti, kako lahko bakterije, ti preprosti organizmi,
04:01
tell the difference from times when they're alone,
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zaznajo, kdaj so same
04:03
and times when they're in a community,
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in kdaj so v skupini,
04:05
and then all do something together.
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da potem skupaj nekaj izvedejo.
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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Ugotovili smo, da to dosežejo z medsebojnim sporazumevanjem,
04:12
and they talk with a chemical language.
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nekakšnim kemičnim jezikom.
04:14
This is now supposed to be my bacterial cell.
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Predpostavimo, da je to naša bakterijska celica.
04:17
When it's alone it doesn't make any light.
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Ko je sama, ne ustvarja svetlobe.
04:20
But what it does do is to make and secrete small molecules
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Namesto tega proizvaja in izloča majhne molekule,
04:24
that you can think of like hormones,
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ki si jih lahko predstavljate kot hormone --
04:26
and these are the red triangles, and when the bacteria is alone
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predstavljajo jih rdeči trikotniki -- in ko je bakterija sama,
04:29
the molecules just float away and so no light.
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molekule le odplavajo stran in svetlobe ni.
04:32
But when the bacteria grow and double
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Ko pa se bakterije pomnožijo,
04:34
and they're all participating in making these molecules,
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vse sodelujejo pri sproščanju takih molekul,
04:37
the molecule -- the extracellular amount of that molecule
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izvencelična količina teh molekul se torej prav tako pomnoži
04:41
increases in proportion to cell number.
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v sorazmerju s številom celic.
04:44
And when the molecule hits a certain amount
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Ko molekula doseže količino,
04:46
that tells the bacteria how many neighbors there are,
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ki sporoči bakterijam, koliko sosednjih celic je,
04:49
they recognize that molecule
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skupaj prepoznajo to molekulo
04:51
and all of the bacteria turn on light in synchrony.
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in skupaj ustvarijo svetlobo.
04:54
That's how bioluminescence works --
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Tako deluje bioluminescenca --
04:56
they're talking with these chemical words.
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sporazumevajo se s kemičnimi besedami.
04:58
The reason that Vibrio fischeri is doing that comes from the biology.
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Razlog, da Vibrio fisceri to počne, je biološki.
05:02
Again, another plug for the animals in the ocean,
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Tu je še eno morsko bitje --
05:05
Vibrio fischeri lives in this squid.
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ta ligenj je namreč njen gostitelj.
05:08
What you are looking at is the Hawaiian Bobtail Squid,
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Na sliki je ligenj Euprymna scolopes,
05:10
and it's been turned on its back,
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obrnjen na hrbet
05:12
and what I hope you can see are these two glowing lobes
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in upam, da vidite dva svetleča režnja,
05:15
and these house the Vibrio fischeri cells,
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v katerih živijo celice Vibro fischeri
05:18
they live in there, at high cell number
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in v velikem številu
05:20
that molecule is there, and they're making light.
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ustvarjajo svetlobo.
05:22
The reason the squid is willing to put up with these shenanigans
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Ligenj te vsiljivce gosti,
05:25
is because it wants that light.
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ker potrebuje njihovo svetlobo.
05:27
The way that this symbiosis works
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Živijo v sožitju,
05:29
is that this little squid lives just off the coast of Hawaii,
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mehkužec pa živi blizu havajskih obal
05:33
just in sort of shallow knee-deep water.
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v zelo nizki vodi.
05:35
The squid is nocturnal, so during the day
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Ta ligenj je nočna žival, tekom dneva
05:38
it buries itself in the sand and sleeps,
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namreč zakopan v pesek spi,
05:40
but then at night it has to come out to hunt.
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ponoči pa pride ven na lov.
05:43
On bright nights when there is lots of starlight or moonlight
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Zaradi plitkosti vode, kjer ligenj živi,
05:45
that light can penetrate the depth of the water
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zvezdna ali lunina svetloba
05:48
the squid lives in, since it's just in those couple feet of water.
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zlahka prodre do morskega dna.
05:51
What the squid has developed is a shutter
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Ligenj je razvil zaslonko,
05:54
that can open and close over this specialized light organ housing the bacteria.
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s katero odstira in zastira ta poseben organ, ki gosti bakterijo.
05:58
Then it has detectors on its back
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Na hrbtu ima senzorje za določanje
06:00
so it can sense how much starlight or moonlight is hitting its back.
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jakosti zvezdne ali lunine svetlobe na njem.
06:04
And it opens and closes the shutter
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Glede na to odpira in zapira zaslonko,
06:06
so the amount of light coming out of the bottom --
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da se jakost svetlobe, ki jo bakterije
06:08
which is made by the bacterium --
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sproščajo na njegovi spodnji strani,
06:10
exactly matches how much light hits the squid's back,
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natanko ujema s svetlobo na hrbtu,
06:12
so the squid doesn't make a shadow.
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zato pod sabo ne ustvarja sence.
06:14
It actually uses the light from the bacteria
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S svetlobo bakterij torej
06:17
to counter-illuminate itself in an anti-predation device
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osvetli osenčeno površino pod sabo,
06:20
so predators can't see its shadow,
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da plenilci ne zaznajo njegove sence
06:22
calculate its trajectory, and eat it.
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in ga tako tudi ne morejo upleniti.
06:24
This is like the stealth bomber of the ocean.
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Je torej nekakšen oceanski nevidni bombnik.
06:27
(Laughter)
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(Smeh)
06:28
But then if you think about it, the squid has this terrible problem
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A pravzaprav je to zanj tudi težava,
06:31
because it's got this dying, thick culture of bacteria
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saj mu lahko ta razkrajajoča, gosta bakterijska kultura,
06:34
and it can't sustain that.
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ki jo nosi, tudi škodi.
06:36
And so what happens is every morning when the sun comes up
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Zato se ligenj vsako jutro ob sončnem vzhodu
06:38
the squid goes back to sleep, it buries itself in the sand,
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zakoplje v pesek in preko črpalke,
06:41
and it's got a pump that's attached to its circadian rhythm,
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ki se odziva na njegov dnevni ritem,
06:44
and when the sun comes up it pumps out like 95 percent of the bacteria.
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izčrpa 95 odstotkov bakterijskih celic.
06:49
Now the bacteria are dilute, that little hormone molecule is gone,
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Bakterije so zdaj razredčene, malih hormonskih molekul ni,
06:52
so they're not making light --
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zato tudi ni svetlobe,
06:54
but of course the squid doesn't care. It's asleep in the sand.
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kar lignja ne moti, saj spi v pesku.
06:56
And as the day goes by the bacteria double,
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Preko dneva se bakterije pomnožijo,
06:58
they release the molecule, and then light comes on
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izločajo molekule in ponoči ustvarijo svetlobo,
07:01
at night, exactly when the squid wants it.
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točno takrat, ko jo ligenj potrebuje.
07:04
First we figured out how this bacterium does this,
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Najprej smo ugotovili, kako bakterija to izvede,
07:07
but then we brought the tools of molecular biology to this
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nato pa smo z molekularno biologijo
07:10
to figure out really what's the mechanism.
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prišli do spoznanja o tem mehanizmu.
07:12
And what we found -- so this is now supposed to be, again, my bacterial cell --
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Ugotovili smo -- to je torej ta bakterijska celica --
07:16
is that Vibrio fischeri has a protein --
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da Vibrio fischeri vsebuje protein --
07:18
that's the red box -- it's an enzyme that makes
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to je rdeči kvader -- encim, ki ustvari
07:21
that little hormone molecule, the red triangle.
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ta rdeči trikotnik, hormonsko molekulo.
07:24
And then as the cells grow, they're all releasing that molecule
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Ko celice rastejo, vse oddajajo molekulo,
07:26
into the environment, so there's lots of molecule there.
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s katero se napolne okolica.
07:29
And the bacteria also have a receptor on their cell surface
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Bakterije pa imajo na celični površini tudi receptor,
07:33
that fits like a lock and key with that molecule.
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ki se kot ključ ujema s ključavnico -- molekulo.
07:36
These are just like the receptors on the surfaces of your cells.
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Taki receptorji so tudi na celičnih površinah v vašem telesu.
07:39
When the molecule increases to a certain amount --
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Ko se molekula namnoži do določene vrednosti,
07:42
which says something about the number of cells --
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ki sporoča število celic,
07:44
it locks down into that receptor
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se zaklene v ta receptor,
07:46
and information comes into the cells
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podatki pa vstopijo v celice
07:48
that tells the cells to turn on
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in jim sporočijo, naj izvršijo
07:50
this collective behavior of making light.
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skupinsko ustvarjanje svetlobe.
07:53
Why this is interesting is because in the past decade
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To je pomembno, ker smo v zadnjem desetletju dognali,
07:56
we have found that this is not just some anomaly
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da pri tej smešni morski svetleči bakteriji
07:58
of this ridiculous, glow-in-the-dark bacterium that lives in the ocean --
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ne gre le za nepravilnost,
08:01
all bacteria have systems like this.
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pač pa imajo vse bakterije take sisteme.
08:04
So now what we understand is that all bacteria can talk to each other.
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Zdaj je torej jasno, da imajo vse bakterije možnost sporazumevanja.
08:07
They make chemical words, they recognize those words,
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Ustvarjajo kemične besede, jih prepoznavajo
08:10
and they turn on group behaviors
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in se nanje skupinsko odzivajo,
08:12
that are only successful when all of the cells participate in unison.
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pri čemer morajo sodelovati vse celice, da delovanje uspe.
08:17
We have a fancy name for this: we call it quorum sensing.
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Gre za t.i. quorum sensing (zaznavanje celične gostote oz. avtoindukcija).
08:20
They vote with these chemical votes,
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Glasujejo s kemičnimi glasovi,
08:22
the vote gets counted, and then everybody responds to the vote.
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jih preštejejo in nato vse nanje odgovorijo.
08:26
What's important for today's talk
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Pomembno je, da vemo,
08:28
is that we know that there are hundreds of behaviors
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da bakterije na tak kolektiven način
08:30
that bacteria carry out in these collective fashions.
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izvedejo na stotine različnih dejavnosti.
08:33
But the one that's probably the most important to you is virulence.
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Za vas najpomembejši pa je najbrž njihova sposobnost povzročiti bolezen.
08:36
It's not like a couple bacteria get in you
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Ena ali dve bakterijski celici ob vstopu v telo
08:39
and they start secreting some toxins --
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še ne izločata toksinov --
08:41
you're enormous, that would have no effect on you. You're huge.
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človeško telo je namreč ogromno, preveliko, da bi nanj imeli vpliv.
08:44
What they do, we now understand,
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Zdaj torej vemo,
08:47
is they get in you, they wait, they start growing,
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da ob vstopu čakajo, se množijo,
08:50
they count themselves with these little molecules,
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se preko molekul preštejejo
08:52
and they recognize when they have the right cell number
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in ko dosežejo določeno število celic,
08:54
that if all of the bacteria launch their virulence attack together,
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da skupaj sprožijo izbruh bolezni,
08:58
they are going to be successful at overcoming an enormous host.
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bodo zmožne premagati še tako velikega gostitelja.
09:02
Bacteria always control pathogenicity with quorum sensing.
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Bakterije patogenost vedno upravljajo z avtoindukcijo.
09:06
That's how it works.
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Tako to deluje.
09:08
We also then went to look at what are these molecules --
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Nato smo se vrnili tudi k molekulam,
09:11
these were the red triangles on my slides before.
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rdečim trikotnikom na slikah.
09:14
This is the Vibrio fischeri molecule.
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To je molekula bakterije Vibrio fischeri.
09:16
This is the word that it talks with.
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To je beseda, s katero se sporazumeva.
09:18
So then we started to look at other bacteria,
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Začeli smo opazovati še druge bakterije
09:20
and these are just a smattering of the molecules that we've discovered.
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in to je le delček odkritih molekul.
09:23
What I hope you can see
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Upam, da je vidno,
09:25
is that the molecules are related.
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kaj imajo te molekule skupnega.
09:27
The left-hand part of the molecule is identical
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Levi del molekule je identičen
09:29
in every single species of bacteria.
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pri prav vsaki vrsti bakterije.
09:32
But the right-hand part of the molecule is a little bit different in every single species.
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Desni del molekule pa je nekoliko drugačen.
09:36
What that does is to confer
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To v teh jezikih izraža
09:38
exquisite species specificities to these languages.
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posebne značilnosti vrste bakterije.
09:42
Each molecule fits into its partner receptor and no other.
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Vsaka molekula spada zgolj k primernemu receptorju.
09:46
So these are private, secret conversations.
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Gre torej za zasebne, skrivne pogovore
09:49
These conversations are for intraspecies communication.
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znotraj ene vrste.
09:53
Each bacteria uses a particular molecule that's its language
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Vsaka bakterija z določeno molekulo ugotovi,
09:57
that allows it to count its own siblings.
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koliko celic njene vrste jo obkroža.
10:01
Once we got that far we thought
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Verjeli smo, da začenjamo razumeti
10:03
we were starting to understand that bacteria have these social behaviors.
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skupinsko delovanje bakterij.
10:06
But what we were really thinking about is that most of the time
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Seveda pa vemo, da večino časa
10:09
bacteria don't live by themselves, they live in incredible mixtures,
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bakterije ne živijo same, pač pa v gostih mešanicah
10:12
with hundreds or thousands of other species of bacteria.
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stotin, tisočin vrst bakterij.
10:16
And that's depicted on this slide. This is your skin.
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To prikazuje ta slika. To je površina vaše kože.
10:19
So this is just a picture -- a micrograph of your skin.
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Gre le za sliko, približan posnetek kože.
10:22
Anywhere on your body, it looks pretty much like this,
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Kjerkoli na vašem telesu gre za podoben prizor
10:24
and what I hope you can see is that there's all kinds of bacteria there.
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in upam, da vidite, da gre za različne vrste bakterij.
10:28
And so we started to think if this really is about communication in bacteria,
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Pri sporazumevanju bakterij in štetju sorodnih sosed
10:32
and it's about counting your neighbors,
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pa ni dovolj le sposobnost
10:34
it's not enough to be able to only talk within your species.
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sporazumevanja s člani iste vrste.
10:37
There has to be a way to take a census
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Obstajati mora torej tudi način
10:39
of the rest of the bacteria in the population.
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popisa ostalih bakterij v okolici.
10:42
So we went back to molecular biology
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Vrnili smo se k molekularni biologiji
10:44
and started studying different bacteria,
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in začeli preučevati različne vrste bakterij,
10:46
and what we've found now is that
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pri čemer smo ugotovili,
10:48
in fact, bacteria are multilingual.
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da so bakterije pravzaprav večjezične.
10:50
They all have a species-specific system --
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Vse imajo sistem prepoznavanja lastne vrste --
10:53
they have a molecule that says "me."
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molekulo, ki pravi "jaz".
10:55
But then, running in parallel to that is a second system
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A temu vzporedno smo odkrili še
10:58
that we've discovered, that's generic.
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sistem prepoznavanja različnih članov rodu.
11:00
So, they have a second enzyme that makes a second signal
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Obstaja torej še drug encim, ki ustvari drugačen signal
11:03
and it has its own receptor,
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za drugačen receptor --
11:05
and this molecule is the trade language of bacteria.
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ta molekula je jezik sporazumevanja med različnimi bakterijami,
11:08
It's used by all different bacteria
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uporabljajo pa ga
11:10
and it's the language of interspecies communication.
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za medvrstno sporazumevanje.
11:14
What happens is that bacteria are able to count
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Bakterije tako lahko preštejejo člane
11:17
how many of me and how many of you.
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svoje in tuje vrste.
11:20
They take that information inside,
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Glede na podatek
11:22
and they decide what tasks to carry out
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o večinski in manjšinski vrsti
11:24
depending on who's in the minority and who's in the majority
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v katerikoli populaciji se odločijo,
11:28
of any given population.
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kateri postopek naj izvedejo.
11:30
Then again we turn to chemistry,
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Nato smo se vrnili h kemiji
11:32
and we figured out what this generic molecule is --
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in ugotovili sestavo te rodovne molekule --
11:35
that was the pink ovals on my last slide, this is it.
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rožnatih ovalov na zadnji sliki.
11:38
It's a very small, five-carbon molecule.
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To je majhna molekula s petimi atomi ogljika.
11:40
What the important thing is that we learned
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Pomembno je,
11:43
is that every bacterium has exactly the same enzyme
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da ima vsaka bakterija točno enak encim
11:46
and makes exactly the same molecule.
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in ustvari točno enako molekulo.
11:48
So they're all using this molecule
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Tako torej vse uporabljajo to molekulo
11:50
for interspecies communication.
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za medvrstno sporazumevanje.
11:52
This is the bacterial Esperanto.
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To je bakterijski esperanto.
11:55
(Laughter)
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(Smeh)
11:56
Once we got that far, we started to learn
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Nato smo spoznali,
11:58
that bacteria can talk to each other with this chemical language.
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da se bakterije sporazumevajo s tem kemičnim jezikom.
12:01
But what we started to think is that maybe there is something
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Začelo pa nas je zanimati tudi,
12:03
practical that we can do here as well.
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kako bi lahko to praktično uporabili.
12:05
I've told you that bacteria do have all these social behaviors,
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Delovanje bakterij je torej skupinsko,
12:08
they communicate with these molecules.
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sporazumevajo pa se preko teh molekul.
12:11
Of course, I've also told you that one of the important things they do
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Pri tem je pomembno,
12:14
is to initiate pathogenicity using quorum sensing.
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da se patogenost začne z zaznavanjem celične gostote.
12:17
We thought, what if we made these bacteria
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Razmišljali smo, kako bi lahko vplivali na bakterije,
12:19
so they can't talk or they can't hear?
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da se ne bi mogle sporazumevati?
12:22
Couldn't these be new kinds of antibiotics?
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Bi lahko ustvarili novo vrsto antibiotikov?
12:25
Of course, you've just heard and you already know
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Vsi seveda že veste,
12:27
that we're running out of antibiotics.
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da nam zmanjkuje antibiotikov.
12:29
Bacteria are incredibly multi-drug-resistant right now,
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Bakterije so dandanes odporne že na vrsto zdravil,
12:32
and that's because all of the antibiotics that we use kill bacteria.
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saj antibiotiki, kot jih poznamo, bakterijo ubijejo.
12:36
They either pop the bacterial membrane,
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Učinkujejo na membrano bakterij
12:38
they make the bacterium so it can't replicate its DNA.
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oz. na njihovo DNK, da se ne more podvojevati.
12:41
We kill bacteria with traditional antibiotics
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Bakterije uničujemo s tradicionalnimi antibiotiki,
12:44
and that selects for resistant mutants.
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nastanejo pa odporni mutanti.
12:46
And so now of course we have this global problem
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Velik svetovni problem so seveda
12:49
in infectious diseases.
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nalezljive bolezni.
12:51
We thought, well what if we could sort of do behavior modifications,
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Pomislili smo, da bi lahko posegli v delovanje bakterij,
12:54
just make these bacteria so they can't talk, they can't count,
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da se ne bi mogle sporazumevati in preštevati,
12:57
and they don't know to launch virulence.
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kar bi zaustavilo sprožitev bolezni.
13:00
And so that's exactly what we've done, and we've sort of taken two strategies.
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Naredili smo točno to in sicer na dva načina.
13:03
The first one is we've targeted
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Najprej je bil naš cilj
13:05
the intraspecies communication system.
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sistem sporazumevanja znotraj ene vrste.
13:08
So we made molecules that look kind of like the real molecules --
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Ustvarili smo molekule, ki so videti kot prave --
13:11
which you saw -- but they're a little bit different.
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take, kot ste jih videli -- a so nekoliko drugačne.
13:13
And so they lock into those receptors,
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Ko se priklenejo na receptorje bakterij,
13:15
and they jam recognition of the real thing.
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zaustavijo prepoznavanje prave molekule.
13:18
By targeting the red system,
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S ciljanjem na rdeči sistem lahko ustvarimo
13:20
what we are able to do is to make
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molekule prav za določeno vrsto bakterije ali bolezni,
13:22
species-specific, or disease-specific, anti-quorum sensing molecules.
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a ki ne zaznavajo celične gostote.
13:27
We've also done the same thing with the pink system.
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Enako smo naredili z rožnatim sistemom.
13:30
We've taken that universal molecule and turned it around a little bit
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Univerzalno molekulo smo spremenili tako,
13:33
so that we've made antagonists
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da smo onemogočili tudi
13:35
of the interspecies communication system.
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medvrstni sistem sporazumevanja.
13:37
The hope is that these will be used as broad-spectrum antibiotics
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Upamo, da bodo taki antibiotiki široko uporabni
13:42
that work against all bacteria.
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proti vsem bakterijam.
13:44
To finish I'll just show you the strategy.
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Za konec naj predstavim to strategijo.
13:47
In this one I'm just using the interspecies molecule,
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Tu je prikazana molekula medvrstnega sporazumevanja,
13:49
but the logic is exactly the same.
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a način delovanja je isti.
13:51
What you know is that when that bacterium gets into the animal,
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Ko bakterija pride v žival,
13:54
in this case, a mouse,
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v tem primeru v miš,
13:56
it doesn't initiate virulence right away.
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bolezni ne sproži takoj.
13:58
It gets in, it starts growing, it starts secreting
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Najprej začne rasti in izločati molekule,
14:01
its quorum sensing molecules.
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ki zaznavajo celično gostoto.
14:03
It recognizes when it has enough bacteria
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Ko bakterije dosežejo zadostno število,
14:05
that now they're going to launch their attack,
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sprožijo bolezen
14:07
and the animal dies.
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in žival pogine.
14:09
What we've been able to do is to give these virulent infections,
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Vnesli smo bolezenske bakterije,
14:12
but we give them in conjunction with our anti-quorum sensing molecules --
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a hkrati z molekulami, ki ne zaznavajo celične gostote --
14:16
so these are molecules that look kind of like the real thing,
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molekule, ki so videti kot prave, ustrezne,
14:18
but they're a little bit different which I've depicted on this slide.
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a so vseeno nekoliko drugačne, kot lahko vidite.
14:21
What we now know is that if we treat the animal
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Ugotovili smo, da če žival podvržemo
14:24
with a pathogenic bacterium -- a multi-drug-resistant pathogenic bacterium --
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patogeni bakteriji, odporni na številna zdravila,
14:28
in the same time we give our anti-quorum sensing molecule,
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in ji hkrati dodamo molekulo, ki ne zaznava celične gostote,
14:32
in fact, the animal lives.
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žival preživi.
14:34
We think that this is the next generation of antibiotics
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Verjamemo, da je to nova generacija antibiotikov,
14:38
and it's going to get us around, at least initially,
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s katerimi bomo lahko vsaj začasno
14:40
this big problem of resistance.
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premagali težavo odpornosti.
14:42
What I hope you think, is that bacteria can talk to each other,
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Bakterije se torej lahko sporazumevajo
14:45
they use chemicals as their words,
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s kemičnimi besedami,
14:48
they have an incredibly complicated chemical lexicon
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njihov izjemno zapleten nabor
14:51
that we're just now starting to learn about.
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pa smo šele začeli spoznavati.
14:53
Of course what that allows bacteria to do
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S tem bakterije pravzaprav
14:56
is to be multicellular.
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postanejo večcelične.
14:58
So in the spirit of TED they're doing things together
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Podobno kot TED tudi bakterije
15:01
because it makes a difference.
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za dosego sprememb stavijo na sodelovanje.
15:03
What happens is that bacteria have these collective behaviors,
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Obnašajo se kolektivno,
15:07
and they can carry out tasks
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s čimer izvršujejo naloge,
15:09
that they could never accomplish
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ki jih same ne bi
15:11
if they simply acted as individuals.
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nikoli izvedle.
15:13
What I would hope that I could further argue to you
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Upam, da mi bo uspelo utemeljiti,
15:16
is that this is the invention of multicellularity.
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da govorim o začetku večceličnosti.
15:19
Bacteria have been on the Earth for billions of years;
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Bakterije so na Zemlji že milijarde let,
15:23
humans, couple hundred thousand.
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ljudje pa le nekaj sto tisoč.
15:25
We think bacteria made the rules
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Menimo, da so bakterije postavile pravila
15:27
for how multicellular organization works.
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za delovanje večceličnih skupnosti.
15:30
We think, by studying bacteria,
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S preučevanjem bakterij
15:33
we're going to be able to have insight about multicellularity in the human body.
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želimo spoznati tudi večceličnost v človeškem telesu.
15:37
We know that the principles and the rules,
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Če bi nam uspelo razvozlati
15:39
if we can figure them out in these sort of primitive organisms,
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načela in pravila delovanja v teh preprostih organizmih,
15:41
the hope is that they will be applied
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bi jih lahko uporabili
15:43
to other human diseases and human behaviors as well.
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tudi pri človeških boleznih in delovanju.
15:47
I hope that what you've learned
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Upam, da sem pojasnila, da bakterije
15:49
is that bacteria can distinguish self from other.
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znajo ločiti med sebi enakimi in drugačnimi.
15:52
By using these two molecules they can say "me" and they can say "you."
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S tema dvema molekulama lahko rečejo "mi" in "oni".
15:55
Again of course that's what we do,
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To izražamo tudi ljudje,
15:57
both in a molecular way,
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tako na molekularni
15:59
and also in an outward way,
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kot na beseden način,
16:01
but I think about the molecular stuff.
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a sedaj je govora o molekularnem.
16:03
This is exactly what happens in your body.
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Točno to se torej dogaja v vašem telesu.
16:05
It's not like your heart cells and your kidney cells get all mixed up every day,
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Celice vašega srca in ledvic se ne mešajo med sabo,
16:08
and that's because there's all of this chemistry going on,
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saj jim na kemični način
16:11
these molecules that say who each of these groups of cells is,
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molekule povejo, kdo spada h kateri skupini celic
16:14
and what their tasks should be.
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in kaj je njihova naloga.
16:16
Again, we think that bacteria invented that,
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Menimo, da so tak način iznašle bakterije.
16:19
and you've just evolved a few more bells and whistles,
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Človeško telo je sicer razvilo nekoliko bolj zapletene celice,
16:22
but all of the ideas are in these simple systems that we can study.
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a enak princip se vrši v teh preprostih sistemih, ki jih preučujemo.
16:26
The final thing is, again just to reiterate that there's this practical part,
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V praktičnem delu smo torej razvili molekule,
16:30
and so we've made these anti-quorum sensing molecules
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ki ne zaznavajo celične gostote,
16:33
that are being developed as new kinds of therapeutics.
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da bi ustvarili nova zdravila.
16:36
But then, to finish with a plug for all the good and miraculous bacteria
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Da pa ne bi pozabili na vse koristne in čudovite
16:39
that live on the Earth,
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bakterije na Zemlji, smo razvili tudi
16:41
we've also made pro-quorum sensing molecules.
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molekule, ki zaznavajo celično gostoto.
16:43
So, we've targeted those systems to make the molecules work better.
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Na te sisteme smo se osredotočili, da bi tako izboljšali delovanje molekul.
16:46
Remember you have these 10 times or more bacterial cells
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Ne pozabite, da je na in v vašem telesu desetkrat več
16:50
in you or on you, keeping you healthy.
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bakterijskih celic, ki vas ohranjajo zdrave.
16:52
What we're also trying to do is to beef up the conversation
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Poleg tega smo želeli
16:55
of the bacteria that live as mutualists with you,
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izboljšati pogovore med bakterijami,
16:58
in the hopes of making you more healthy,
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ki živijo z vami v sožitju,
17:00
making those conversations better,
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da bi na vaše zdravje in delovanje
17:02
so bacteria can do things that we want them to do
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učinkovale bolje,
17:05
better than they would be on their own.
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kot bi sicer same zase.
17:08
Finally, I wanted to show you
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Za konec vam želim še pokazati
17:10
this is my gang at Princeton, New Jersey.
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mojo družbo na Princetonu v New Jerseyu.
17:12
Everything I told you about was discovered by someone in that picture.
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Vse, o čemer sem vam pripovedovala, je odkrila oseba na tej sliki.
17:16
I hope when you learn things,
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Upam, da se zavedate, da dejstva,
17:18
like about how the natural world works --
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ki se jih učite, jih preberete v časopisu
17:20
I just want to say that whenever you read something in the newspaper
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ali o njih slišite na predavanju
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or you get to hear some talk about something ridiculous in the natural world
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o neverjetnih naravoslovnih odkritjih,
17:26
it was done by a child.
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so odkrili mladi ljudje.
17:28
Science is done by that demographic.
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Znanost se odvija v tej starostni skupini.
17:30
All of those people are between 20 and 30 years old,
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Vsi od njih so stari med dvajset in trideset let
17:34
and they are the engine that drives scientific discovery in this country.
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in predstavljajo gonilo znanstvenih odkritij v tej državi.
17:38
It's a really lucky demographic to work with.
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Krasno je sodelovati z njimi.
17:41
I keep getting older and older and they're always the same age,
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Jaz se staram, ta skupina pa je vedno enakih let,
17:44
and it's just a crazy delightful job.
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zato v tem delu res izjemno uživam.
17:47
I want to thank you for inviting me here.
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Najlepša hvala za vabilo.
17:49
It's a big treat for me to get to come to this conference.
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Zelo sem vesela sem, da sem lahko sodelovala na tej konferenci.
17:52
(Applause)
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(Aplavz)
17:57
Thanks.
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Hvala.
17:58
(Applause)
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(Aplavz)
ABOUT THE SPEAKER
Bonnie Bassler - Molecular biologistBonnie 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.
Bonnie Bassler | Speaker | TED.com