TED2009
Bonnie Bassler: How bacteria "talk"
博妮 柏索：细菌是怎样交流的？
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博妮 柏索发现细菌间是会交谈的，它们用一种化学语言来达到共同防卫，协同攻击的行为。这个发现对今后的医疗，工业有着重大的意义，包括怎样认识我们人类自己。
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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细菌是地球上最古老的生物.
00:21
They've been here for billions of years,
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它们已经存在数十亿年了
00:23
and what they are are single-celled microscopic organisms.
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它们是单细胞微生物
00:27
So they are one cell and they have this special property
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它们特征是只有一个细胞
00:30
that they only have one piece of DNA.
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还有就是它们只有一份DNA
00:32
They have very few genes,
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它们只有少量基因,
00:34
and genetic information to encode all of the traits that they carry out.
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和遗传信息来编码它们表达的特性。
00:38
And the way bacteria make a living
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细菌生存的方法
00:40
is that they consume nutrients from the environment,
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是不断从环境中吸取养分©
00:43
they grow to twice their size, they cut themselves down in the middle,
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在成长到两倍的体积后，它们从中一分为二
00:46
and one cell becomes two, and so on and so on.
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分裂为两个细胞，如此循环
00:49
They just grow and divide, and grow and divide -- so a kind of boring life,
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它们不停得生长、分裂，然后再生长、再分裂—过着有点乏味的生活。
00:53
except that what I would argue is that you have
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但是，今天我想告诉你
00:55
an amazing interaction with these critters.
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你与这些细菌有着惊人的互动关系
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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我知道你认为你自己是人类，而这可能也是我如何看你们的
01:01
This man is supposed to represent
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在这里的是
01:03
a generic human being,
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一个一般人类的代表
01:05
and all of the circles in that man are all of the cells that make up your body.
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在他身上所有的圆圈代表着各个组成人体的细胞
01:09
There is about a trillion human cells that make each one of us
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每个人体大约是由一兆个人体细胞所组成
01:12
who we are and able to do all the things that we do,
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它们让我们能完成各种各样我们想做的事情
01:15
but you have 10 trillion bacterial cells
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但是，你一生中的每时每刻，
01:18
in you or on you at any moment in your life.
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有大约十兆个细菌细胞生活在你的体内体表。
01:20
So, 10 times more bacterial cells
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所以，有十倍于人体细胞的细菌细胞
01:22
than human cells on a human being.
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生活在一个人身上
01:25
And of course it's the DNA that counts,
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同理, 我们要算一下DNA
01:27
so here's all the A, T, Gs and Cs
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这是所有的 A, T, G 和 C (腺嘌呤, 胸腺嘧啶, 鸟嘌呤, 胞嘧啶)
01:29
that make up your genetic code, and give you all your charming characteristics.
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组成你的基因密码, 赋予你所有的魅力特征.
01:32
You have about 30,000 genes.
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你有3万左右的遗传基因,
01:34
Well it turns out you have 100 times more bacterial genes
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而围绕你的细菌的遗传基因数量是你自己的100倍
01:37
playing a role in you or on you all of your life.
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它们在你的身体内部和表面上中始终扮演着重要的角色。
01:41
At the best, you're 10 percent human,
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最乐观的看法是: 你只是"10分之1人",
01:44
but more likely about one percent human,
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事实上"100分之一人"更准确，
01:46
depending on which of these metrics you like.
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取决于你更喜欢用哪个尺度来衡量.
01:48
I know you think of yourself as human beings,
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我知道你自认为是一个"人类",
01:50
but I think of you as 90 or 99 percent bacterial.
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但在我眼里你是90%~99%的细菌.
01:54
(Laughter)
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(笑)
01:55
These bacteria are not passive riders,
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这些细菌不是顺从的乘客,
01:58
these are incredibly important, they keep us alive.
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他们难以置信得重要, 他们让我们活着.
02:01
They cover us in an invisible body armor
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它们是我们身上的无形盔甲
02:04
that keeps environmental insults out
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阻断来之环境的伤害
02:06
so that we stay healthy.
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保持我们的健康.
02:08
They digest our food, they make our vitamins,
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它们消化食物, 制造维他命,
02:10
they actually educate your immune system
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它们还指导你的免疫系统
02:12
to keep bad microbes out.
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将有害微生物阻挡在体外。
02:14
So they do all these amazing things
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它们尽心尽职干活
02:16
that help us and are vital for keeping us alive,
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帮助我们，维护我们的生命。
02:20
and they never get any press for that.
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却从没有因此得到过报道.
02:22
But they get a lot of press because they do a lot of
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反而却因为它们同时做的许多
02:24
terrible things as well.
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坏事而时常见报。
02:26
So, there's all kinds of bacteria on the Earth
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地球上有无数种细菌
02:29
that have no business being in you or on you at any time,
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它们有些在任何时候都绝对不应该出现在你的体内体表，
02:32
and if they are, they make you incredibly sick.
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然而假如你不幸遇到了, 那你一定会病得很厉害。
02:36
And so, the question for my lab is whether you want to think about all the
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所以, 我们实验室研究的问题是, 正是你想知道的
02:39
good things that bacteria do, or all the bad things that bacteria do.
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细菌做的所有好事或者细菌做的所有坏事。
02:43
The question we had is how could they do anything at all?
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我们曾经提出一个疑问: 它们究竟是怎么做到的?
02:45
I mean they're incredibly small,
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我指的是, 它们是那么细微,
02:47
you have to have a microscope to see one.
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用显微镜才能看到一个。
02:49
They live this sort of boring life where they grow and divide,
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它们的生活好像只是单调乏味的成长与分裂，
02:52
and they've always been considered to be these asocial reclusive organisms.
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而且长久以来被认为是不善社交的隐居生命体。
02:57
And so it seemed to us that they are just too small to have an impact
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所以在我们看来, 它们实在是太渺小，
03:00
on the environment
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如果单枪匹马
03:02
if they simply act as individuals.
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根本到无法对环境产生任何影响。
03:04
And so we wanted to think if there couldn't be a different
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所以我们正在探讨
03:06
way that bacteria live.
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细菌是不是有着特殊的生存方式。
03:08
The clue to this came from another marine bacterium,
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解答这个问题的线索
03:12
and it's a bacterium called Vibrio fischeri.
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来自一种叫做费氏弧菌的海洋细菌。
03:15
What you're looking at on this slide is just a person from my lab
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你们在这张幻灯看到的，是我实验室的一个工作人员
03:18
holding a flask of a liquid culture of a bacterium,
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握着一瓶装满这种细菌的培养液，
03:21
a harmless beautiful bacterium that comes from the ocean,
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这是一种来自海洋的，美丽而且无害的细菌：
03:24
named Vibrio fischeri.
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"费氏弧菌".
03:26
This bacterium has the special property that it makes light,
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这种细菌的特性是会发光，
03:29
so it makes bioluminescence,
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产生生物荧光,
03:31
like fireflies make light.
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像萤火虫一样。
03:33
We're not doing anything to the cells here.
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我们没有对这些细胞做任何处理。
03:35
We just took the picture by turning the lights off in the room,
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我们只是把房间灯关了，然后照了这张照片，
03:37
and this is what we see.
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这是我们所见到的情形。
03:39
What was actually interesting to us
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事实上, 我们感兴趣的部分
03:41
was not that the bacteria made light,
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并不是细菌会不会发光，
03:43
but when the bacteria made light.
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而是细菌何时发光。
03:45
What we noticed is when the bacteria were alone,
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我们发现, 当细菌独立存在,
03:48
so when they were in dilute suspension, they made no light.
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经稀释后进行悬浮培养时, 它们不发光。
03:51
But when they grew to a certain cell number
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但一旦它们增长到一个特定数量之后
03:53
all the bacteria turned on light simultaneously.
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所有的细菌同时发光。
03:57
The question that we had is how can bacteria, these primitive organisms,
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于是我们想, 这些原始生物,
04:01
tell the difference from times when they're alone,
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到底如何得知自己是处于孤立的状态,
04:03
and times when they're in a community,
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还是处在一个群体里，
04:05
and then all do something together.
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并且同时一起做同一件事情。
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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然后我们发现了这是因为细菌能够彼此交谈，
04:12
and they talk with a chemical language.
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它们用的是化学语言。
04:14
This is now supposed to be my bacterial cell.
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假设这是我的细菌。
04:17
When it's alone it doesn't make any light.
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当它独处时, 丝毫不会发光。
04:20
But what it does do is to make and secrete small molecules
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但是它们会制造分泌小化学分子
04:24
that you can think of like hormones,
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你可以把他想象成荷尔蒙,
04:26
and these are the red triangles, and when the bacteria is alone
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这里的红色三角形代表这些小分子, 当细菌独处时，
04:29
the molecules just float away and so no light.
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分泌的小分子游离开来,所以不发光。
04:32
But when the bacteria grow and double
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随着这些细菌成倍增长,
04:34
and they're all participating in making these molecules,
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且全部一起制造这些分子,
04:37
the molecule -- the extracellular amount of that molecule
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这些细胞外分子的含量
04:41
increases in proportion to cell number.
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随着细胞数量的增加而增加，
04:44
And when the molecule hits a certain amount
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当这些个分子累积到一定的量之后，
04:46
that tells the bacteria how many neighbors there are,
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它们会告诉了细菌，它们周围有多少邻居，
04:49
they recognize that molecule
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细菌接受到这些信息后，
04:51
and all of the bacteria turn on light in synchrony.
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所有的细菌，同时开始发光。
04:54
That's how bioluminescence works --
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生物光就是这样运作的 --
04:56
they're talking with these chemical words.
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它们籍由上述的化学语言交流。
04:58
The reason that Vibrio fischeri is doing that comes from the biology.
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费氏弧菌的发光现象来自生物学上的原因。
05:02
Again, another plug for the animals in the ocean,
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接下来,我们再来看一个海洋生物：
05:05
Vibrio fischeri lives in this squid.
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费式弧菌寄生在这种乌贼的体内。
05:08
What you are looking at is the Hawaiian Bobtail Squid,
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你们现在看到的是夏威夷截尾乌贼,
05:10
and it's been turned on its back,
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这是它的腹侧,
05:12
and what I hope you can see are these two glowing lobes
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我希望你们看得到，那两个发着光的叶状突起，
05:15
and these house the Vibrio fischeri cells,
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这里是费式弧菌的寄生之处，
05:18
they live in there, at high cell number
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他们居住在这里面。
05:20
that molecule is there, and they're making light.
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他们分泌的小分子也在这里面,所以它们能够发光。
05:22
The reason the squid is willing to put up with these shenanigans
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这种乌贼之所以愿意接受它们在里面胡作非为
05:25
is because it wants that light.
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是因为它需要这些亮光。
05:27
The way that this symbiosis works
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这种共存行为的建立基础
05:29
is that this little squid lives just off the coast of Hawaii,
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是因为这种小乌贼生活在夏威夷的海岸，
05:33
just in sort of shallow knee-deep water.
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大概只有膝盖一般深的水里。
05:35
The squid is nocturnal, so during the day
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这种乌贼是夜行性的，
05:38
it buries itself in the sand and sleeps,
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因此在白天它们藏在沙子里睡觉，
05:40
but then at night it has to come out to hunt.
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但是到了晚上，它们必须出来猎食。
05:43
On bright nights when there is lots of starlight or moonlight
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在有着许多星光与月光的明亮夜晚，
05:45
that light can penetrate the depth of the water
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这些光线可以照透乌贼所生活的地方
05:48
the squid lives in, since it's just in those couple feet of water.
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因为这里的海水只有数尺深而已
05:51
What the squid has developed is a shutter
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这种乌贼演化出了一种活叶瓣，
05:54
that can open and close over this specialized light organ housing the bacteria.
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可以打开或关闭细菌所寄生的发光器官。
05:58
Then it has detectors on its back
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这种乌贼背上有一些感光装置，
06:00
so it can sense how much starlight or moonlight is hitting its back.
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可以测量有多少月光或星光照在它背上，
06:04
And it opens and closes the shutter
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然后调节它的活叶瓣。
06:06
so the amount of light coming out of the bottom --
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使从它腹部所放出的光
06:08
which is made by the bacterium --
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细菌产生的光
06:10
exactly matches how much light hits the squid's back,
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完全符合照射在乌贼背上的光强度
06:12
so the squid doesn't make a shadow.
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因此这乌贼就不会产生任何影子。
06:14
It actually uses the light from the bacteria
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它们使用来自细菌的光，
06:17
to counter-illuminate itself in an anti-predation device
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不断调节光线，就像穿上隐身衣，
06:20
so predators can't see its shadow,
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使猎食者无法看见它的阴影，
06:22
calculate its trajectory, and eat it.
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计算它的动向，然后吃了它。
06:24
This is like the stealth bomber of the ocean.
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就像是大海中的隐形轰炸机一般。
06:27
(Laughter)
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（笑声）
06:28
But then if you think about it, the squid has this terrible problem
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但是如果你再深入地想一下，这乌贼会有一个可怕的问题
06:31
because it's got this dying, thick culture of bacteria
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因为在它的体内，这些黏稠的细菌会不断的增长，死亡，
06:34
and it can't sustain that.
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乌贼无法无限地维持这种状态。
06:36
And so what happens is every morning when the sun comes up
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因此每天早上太阳升起后，
06:38
the squid goes back to sleep, it buries itself in the sand,
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它将自己埋藏在沙子里睡觉，
06:41
and it's got a pump that's attached to its circadian rhythm,
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它有一个与日夜周期同步的活泵
06:44
and when the sun comes up it pumps out like 95 percent of the bacteria.
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当太阳升起时，它将大约95%的细菌排出体外。
06:49
Now the bacteria are dilute, that little hormone molecule is gone,
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当细菌被稀释了，这些小荷尔蒙分子也随之消失，
06:52
so they're not making light --
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因此它们就不发光了，
06:54
but of course the squid doesn't care. It's asleep in the sand.
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但这时乌贼完全不在乎，因为它正在沙子里睡觉呢。
06:56
And as the day goes by the bacteria double,
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当白天过去，这些细菌持续分裂增长，
06:58
they release the molecule, and then light comes on
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它们释放出足够的这些小分子，然后又开始在晚上发光，
07:01
at night, exactly when the squid wants it.
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这时正好又是乌贼需要光线的时候。
07:04
First we figured out how this bacterium does this,
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我们首先了解了这些细菌为什么会有这种现象，
07:07
but then we brought the tools of molecular biology to this
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然后我们使用分子生物学的方法
07:10
to figure out really what's the mechanism.
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来研究这种现象的真正的机理。
07:12
And what we found -- so this is now supposed to be, again, my bacterial cell --
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我们发现了：比如这是我的费氏弧菌
07:16
is that Vibrio fischeri has a protein --
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它有一种蛋白质－
07:18
that's the red box -- it's an enzyme that makes
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就是这个红色的方块—它是一种催化剂，
07:21
that little hormone molecule, the red triangle.
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是它制造的这种小荷尔蒙分子，就是这红色三角形。
07:24
And then as the cells grow, they're all releasing that molecule
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当细胞生长时，他们全都释放这个种分子到环境中，
07:26
into the environment, so there's lots of molecule there.
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因此周围环境中有大量的这种分子。
07:29
And the bacteria also have a receptor on their cell surface
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这些细菌的细胞表面，存在一种受体，
07:33
that fits like a lock and key with that molecule.
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它与小分子的构造就如同锁与钥匙一般的吻合。
07:36
These are just like the receptors on the surfaces of your cells.
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它们就如同你我身体细胞表面上的受体一般。
07:39
When the molecule increases to a certain amount --
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当这些分子增加到一定的量时—
07:42
which says something about the number of cells --
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这也意味着这些细胞的数量增加到一定的量
07:44
it locks down into that receptor
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荷尔蒙小分子与受器相结合，
07:46
and information comes into the cells
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讯息开始向细胞内部传递，
07:48
that tells the cells to turn on
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这个讯息会告诉这些细胞
07:50
this collective behavior of making light.
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开始集体发光的行为。
07:53
Why this is interesting is because in the past decade
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这个发现之所以有趣，是因为在过去十年间
07:56
we have found that this is not just some anomaly
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我们发现这种现象，
07:58
of this ridiculous, glow-in-the-dark bacterium that lives in the ocean --
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不只局限在这种住在大海中，古怪的、会在黑暗中发光的细菌，
08:01
all bacteria have systems like this.
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而是所有的细菌都有类似的系统。
08:04
So now what we understand is that all bacteria can talk to each other.
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由此，我们发现所有细菌都是可以彼此交谈的。
08:07
They make chemical words, they recognize those words,
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它们制造化学文字，同时也能够辨认这些文字，
08:10
and they turn on group behaviors
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然后表现
08:12
that are only successful when all of the cells participate in unison.
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只有当所有细胞齐心协力才能成功的集体行为。
08:17
We have a fancy name for this: we call it quorum sensing.
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我们为这种行为取了一个新潮的名字，称作：聚量感应。
08:20
They vote with these chemical votes,
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就象用化学物质投票，
08:22
the vote gets counted, and then everybody responds to the vote.
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再对票量加以统计，然后 所有细胞都要服从最后的投票结果。
08:26
What's important for today's talk
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今天演讲最重要的一点是，
08:28
is that we know that there are hundreds of behaviors
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我们已经知道细菌有数百种以上的这种
08:30
that bacteria carry out in these collective fashions.
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集体行为。
08:33
But the one that's probably the most important to you is virulence.
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其中对大家来说，最关心的应该还是细菌的致病性。
08:36
It's not like a couple bacteria get in you
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并不是说少量细菌进入你体内后
08:39
and they start secreting some toxins --
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就马上开始分泌毒素。
08:41
you're enormous, that would have no effect on you. You're huge.
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相对它们来说，你是个庞然大物，少量细菌对你不会有任何的影响。
08:44
What they do, we now understand,
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我们发现，
08:47
is they get in you, they wait, they start growing,
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它们是先进入你的体内，然后等待，开始不断复制增长，
08:50
they count themselves with these little molecules,
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它们由统计小分子的数目来估计自身的实力，
08:52
and they recognize when they have the right cell number
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当确定有足够的细胞数后，
08:54
that if all of the bacteria launch their virulence attack together,
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所有细菌一起发动致病攻击，
08:58
they are going to be successful at overcoming an enormous host.
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这样它们就能成功攻陷巨大的宿主。
09:02
Bacteria always control pathogenicity with quorum sensing.
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细菌总是以「聚量感应」来控制其致病性
09:06
That's how it works.
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这就是它们运作的原理。
09:08
We also then went to look at what are these molecules --
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我们同时也研究了这些小分子，
09:11
these were the red triangles on my slides before.
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这些就是我刚才幻灯上的小红三角形。
09:14
This is the Vibrio fischeri molecule.
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这个是费氏弧菌的小分子。
09:16
This is the word that it talks with.
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也就是它们用以交谈的文字。
09:18
So then we started to look at other bacteria,
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我们开始研究其他细菌，
09:20
and these are just a smattering of the molecules that we've discovered.
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这些是部份我们已发现小分子
09:23
What I hope you can see
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我希望你们看得出来
09:25
is that the molecules are related.
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这些分子之间是有关联性的。
09:27
The left-hand part of the molecule is identical
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每种细菌，
09:29
in every single species of bacteria.
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它们的小分子的左半部都是完全相同的。
09:32
But the right-hand part of the molecule is a little bit different in every single species.
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只是在右半部则因菌种的不同而有少许的不同。
09:36
What that does is to confer
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这个发现证实
09:38
exquisite species specificities to these languages.
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细菌的语言有高度的专一性。
09:42
Each molecule fits into its partner receptor and no other.
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每一种分子只能与其相对受器结合，非常专一。
09:46
So these are private, secret conversations.
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所以这些交谈是私下的、秘密的。
09:49
These conversations are for intraspecies communication.
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这种交流是只限于同种族内部的沟通。
09:53
Each bacteria uses a particular molecule that's its language
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每一种细菌使用其特殊分子代表它的语言，
09:57
that allows it to count its own siblings.
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让它能够计算同类的数量。
10:01
Once we got that far we thought
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一旦我们了解这些，
10:03
we were starting to understand that bacteria have these social behaviors.
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我们也开始了解细菌有所谓的社交行为。
10:06
But what we were really thinking about is that most of the time
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但我们真正思考的问题是，
10:09
bacteria don't live by themselves, they live in incredible mixtures,
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在多数情况下，细菌并不是单独生活的，它们居住的地方是鱼龙混杂的，
10:12
with hundreds or thousands of other species of bacteria.
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它们跟其它成百上千种的细菌同居一处。
10:16
And that's depicted on this slide. This is your skin.
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这张幻灯可以说明这个情形：这是你的皮肤。
10:19
So this is just a picture -- a micrograph of your skin.
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这是一张照片，是你皮肤的显微照片。
10:22
Anywhere on your body, it looks pretty much like this,
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在你身体的任何地方，看上去都会和这差不多。
10:24
and what I hope you can see is that there's all kinds of bacteria there.
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我希望你能看出，这里有各种不同的细菌。
10:28
And so we started to think if this really is about communication in bacteria,
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因此我们开始思考，如果这真的是细菌间的交流
10:32
and it's about counting your neighbors,
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计算与之相邻的同种细菌的数量，
10:34
it's not enough to be able to only talk within your species.
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只跟同种细菌沟通是不够的，
10:37
There has to be a way to take a census
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它们一定有某种
10:39
of the rest of the bacteria in the population.
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跟周围其他种细菌和平共处的方法。
10:42
So we went back to molecular biology
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所以我们回到分子生物学的方法，
10:44
and started studying different bacteria,
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开始研究不同的细菌。
10:46
and what we've found now is that
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我们现在已经发现，
10:48
in fact, bacteria are multilingual.
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事实上，细菌可以讲多国种语言。
10:50
They all have a species-specific system --
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它们都有一个菌种特别识别系统，
10:53
they have a molecule that says "me."
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用特别分子来辨别同类。
10:55
But then, running in parallel to that is a second system
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但是，我们发现，
10:58
that we've discovered, that's generic.
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它们同时还有另一种系统，那是一个通用的系统。
11:00
So, they have a second enzyme that makes a second signal
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因此，它们有另一种催化剂，能产生第二种信号，
11:03
and it has its own receptor,
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这种信号也有自己的受体，
11:05
and this molecule is the trade language of bacteria.
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这种分子是细菌们的公共语言。
11:08
It's used by all different bacteria
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它被所有不同的细菌所公共使用，
11:10
and it's the language of interspecies communication.
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是一种菌种间沟通的语言。
11:14
What happens is that bacteria are able to count
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细菌能够计算
11:17
how many of me and how many of you.
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并区分自己周围同种与异种细菌的数量。
11:20
They take that information inside,
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它们传递这些讯息到细胞内，
11:22
and they decide what tasks to carry out
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然后决定该怎么做，
11:24
depending on who's in the minority and who's in the majority
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它们的行动取决于在整个群体中
11:28
of any given population.
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谁占多数，谁占少数。
11:30
Then again we turn to chemistry,
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我们又使用化学方法
11:32
and we figured out what this generic molecule is --
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搞清了这个通用分子的构造－
11:35
that was the pink ovals on my last slide, this is it.
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通用分子就是我上一张幻灯的粉红色椭圆形。
11:38
It's a very small, five-carbon molecule.
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它是一个非常小的五碳分子。
11:40
What the important thing is that we learned
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重要的是，我们发现
11:43
is that every bacterium has exactly the same enzyme
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每种细菌都有完全一样的催化剂，
11:46
and makes exactly the same molecule.
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可以制造一模一样的分子。
11:48
So they're all using this molecule
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它们都使用这个分子
11:50
for interspecies communication.
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作为菌种间交流的语言。
11:52
This is the bacterial Esperanto.
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这是细菌的世界语。
11:55
(Laughter)
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笑声
11:56
Once we got that far, we started to learn
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一旦我们了解这个后，
11:58
that bacteria can talk to each other with this chemical language.
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我们知道细菌可以用这个分子来相互交流。
12:01
But what we started to think is that maybe there is something
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但是我们又开始思考，
12:03
practical that we can do here as well.
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也许我们可以使用这个发现来做一些实质上的应用。
12:05
I've told you that bacteria do have all these social behaviors,
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我已经告诉过你们，细菌间是有社交行为的，
12:08
they communicate with these molecules.
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它们是使用这些分子进行交流的。
12:11
Of course, I've also told you that one of the important things they do
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当然，我也告诉过你，
12:14
is to initiate pathogenicity using quorum sensing.
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其中一件主要的事情就是它们使用聚量感应来启动致病性。
12:17
We thought, what if we made these bacteria
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我们不禁想，我们是不是
12:19
so they can't talk or they can't hear?
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可以让这些细菌哑了或聋了？
12:22
Couldn't these be new kinds of antibiotics?
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这岂不是可以成为一种新的抗生素？
12:25
Of course, you've just heard and you already know
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当然，你一定听说过，而且你早就知道了
12:27
that we're running out of antibiotics.
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我们快要没有有效的抗生素了。
12:29
Bacteria are incredibly multi-drug-resistant right now,
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现在的细菌都拥有，不可思议的多重耐药性
12:32
and that's because all of the antibiotics that we use kill bacteria.
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而这都是因为，这些抗生素的工作原理都是杀死细菌。
12:36
They either pop the bacterial membrane,
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它们要么是使细菌的细胞膜破裂，
12:38
they make the bacterium so it can't replicate its DNA.
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就是不让细菌复制自己的DNA。
12:41
We kill bacteria with traditional antibiotics
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当我们用传统抗生素来杀菌时，
12:44
and that selects for resistant mutants.
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会同时培养筛选出有耐药性的突变菌株。
12:46
And so now of course we have this global problem
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所以，我们有了全球性的
12:49
in infectious diseases.
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感染病问题。
12:51
We thought, well what if we could sort of do behavior modifications,
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我们想，如果我们可以稍微更改这些细菌的行为，
12:54
just make these bacteria so they can't talk, they can't count,
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只是让这些细菌无法交谈，无法计数，
12:57
and they don't know to launch virulence.
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它们就不知何时发起毒性攻击。
13:00
And so that's exactly what we've done, and we've sort of taken two strategies.
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这就是我们已经完成的实验，我们使用了两种不同策略：
13:03
The first one is we've targeted
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第一个，
13:05
the intraspecies communication system.
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我们锁定菌种内通讯系统。
13:08
So we made molecules that look kind of like the real molecules --
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我们制造了一些看起来跟真的分子很像的分子，
13:11
which you saw -- but they're a little bit different.
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你们可以看到，它们间只有一点点的不同。
13:13
And so they lock into those receptors,
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因此，它们会锁住这些受体，
13:15
and they jam recognition of the real thing.
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并且干扰受体辨识真正的分子。
13:18
By targeting the red system,
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既然锁定红色的系统，
13:20
what we are able to do is to make
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我们就可以制造
13:22
species-specific, or disease-specific, anti-quorum sensing molecules.
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针对菌种，或是针对疾病的「反聚量感应」分子。
13:27
We've also done the same thing with the pink system.
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我们也对粉红色系统做了同样的事情。
13:30
We've taken that universal molecule and turned it around a little bit
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我们使用那种通用分子，将之做了一些更改
13:33
so that we've made antagonists
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我们做了一些拮抗剂，
13:35
of the interspecies communication system.
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它们都是针对菌种间的通讯系统。
13:37
The hope is that these will be used as broad-spectrum antibiotics
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我们希望这些分子可以用来作广谱抗生素，
13:42
that work against all bacteria.
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对所有细菌都有效。
13:44
To finish I'll just show you the strategy.
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最后，我只跟你们说一下战略。
13:47
In this one I'm just using the interspecies molecule,
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在这个里，我们只是使用跨菌种分子，
13:49
but the logic is exactly the same.
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但是思维逻辑是一模一样的。
13:51
What you know is that when that bacterium gets into the animal,
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你们都知道，当细菌进入动物体内，
13:54
in this case, a mouse,
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以此为例，对这只老鼠，
13:56
it doesn't initiate virulence right away.
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它并不会马上启动致病机制。
13:58
It gets in, it starts growing, it starts secreting
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它进入，开始增殖，
14:01
its quorum sensing molecules.
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开始分泌它的聚量感应分子。
14:03
It recognizes when it has enough bacteria
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当累积到足够数量时，细菌能识别，
14:05
that now they're going to launch their attack,
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并开始发起攻击，
14:07
and the animal dies.
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然后老鼠就死了。
14:09
What we've been able to do is to give these virulent infections,
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我们所做的是在致病感染的同时，
14:12
but we give them in conjunction with our anti-quorum sensing molecules --
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加入我们的「反聚量感应分子」，
14:16
so these are molecules that look kind of like the real thing,
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也就是看起来很像真的「聚量感应分子」的物质，
14:18
but they're a little bit different which I've depicted on this slide.
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但是，正如同我在幻灯上指出的，它们之间有一点点不同。
14:21
What we now know is that if we treat the animal
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我们现在发现，
14:24
with a pathogenic bacterium -- a multi-drug-resistant pathogenic bacterium --
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如果让实验动物感染一种具有多重耐药性的致病细菌，
14:28
in the same time we give our anti-quorum sensing molecule,
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但是同时， 我们施予「反聚量感应分子」治疗，
14:32
in fact, the animal lives.
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动物就能够存活。
14:34
We think that this is the next generation of antibiotics
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我们认为这应该是下一代的抗生素，
14:38
and it's going to get us around, at least initially,
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它将能够让我们，至少在开始阶段，
14:40
this big problem of resistance.
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解决耐药性细菌的问题。
14:42
What I hope you think, is that bacteria can talk to each other,
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我希望你们也能认为，细菌可以彼此交谈，
14:45
they use chemicals as their words,
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它们使用化学物质当作语言，
14:48
they have an incredibly complicated chemical lexicon
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它们拥有极端复杂的化学语汇，
14:51
that we're just now starting to learn about.
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我们现在才刚刚要开始学习这些语汇。
14:53
Of course what that allows bacteria to do
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当然，也因为这些语汇
14:56
is to be multicellular.
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使细菌得以变得像多细胞生物。
14:58
So in the spirit of TED they're doing things together
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所以，就像TED的精神一样，它们彼此合作，
15:01
because it makes a difference.
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因为这样才能有一番作为。
15:03
What happens is that bacteria have these collective behaviors,
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细菌因为有这些集体行为，
15:07
and they can carry out tasks
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所以可以执行
15:09
that they could never accomplish
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一些如果是单枪匹马
15:11
if they simply acted as individuals.
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是永远无法完成的任务。
15:13
What I would hope that I could further argue to you
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我希望能进一步地说服你们的是
15:16
is that this is the invention of multicellularity.
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这就是多细胞生物的起源。
15:19
Bacteria have been on the Earth for billions of years;
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细菌已经生存在地球上数十亿年了。
15:23
humans, couple hundred thousand.
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人类只有数十万年而已。
15:25
We think bacteria made the rules
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我们认为细菌制定了
15:27
for how multicellular organization works.
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多细胞的组织运作规则。
15:30
We think, by studying bacteria,
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我们认为，由研究细菌，
15:33
we're going to be able to have insight about multicellularity in the human body.
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我们将能够对，人体内的多细胞系统，有更进一步的认识。
15:37
We know that the principles and the rules,
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我们现在已经知道基本规则了，
15:39
if we can figure them out in these sort of primitive organisms,
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如果我们可以从这些原始生命体上进一步弄懂它们，
15:41
the hope is that they will be applied
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这些规则也有希望能够应用
15:43
to other human diseases and human behaviors as well.
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到人类其它疾病与行为上。
15:47
I hope that what you've learned
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我希望你们已经学到
15:49
is that bacteria can distinguish self from other.
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细菌是可以区分你我，
15:52
By using these two molecules they can say "me" and they can say "you."
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使用这两种分子，它们可以表达「我」和「你」。
15:55
Again of course that's what we do,
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当然，这就是我们所做的
15:57
both in a molecular way,
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不仅只在分子层面上，
15:59
and also in an outward way,
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同样也在行为上，
16:01
but I think about the molecular stuff.
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只是我在分子层次上想的多一点。
16:03
This is exactly what happens in your body.
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这完全就是你们体内正在发生的事情。
16:05
It's not like your heart cells and your kidney cells get all mixed up every day,
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你们的心脏和肾脏细胞不会每天混杂在一起，
16:08
and that's because there's all of this chemistry going on,
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这是因为你体内有一大堆化学反应不断地进行着，
16:11
these molecules that say who each of these groups of cells is,
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这些分子能够区分不同的细胞群组，
16:14
and what their tasks should be.
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还有它们所应该执行的任务。
16:16
Again, we think that bacteria invented that,
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再一次，我们认为细菌发明了这个机制，
16:19
and you've just evolved a few more bells and whistles,
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你只不过是多演化出了一些铃铛与哨子而已，
16:22
but all of the ideas are in these simple systems that we can study.
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但是所有的概念都包含在这个我们所研究的简单系统中。
16:26
The final thing is, again just to reiterate that there's this practical part,
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最后，只是再一次重申，这个研究的实际应用方面，
16:30
and so we've made these anti-quorum sensing molecules
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是我们已经制造出了这些「反聚量感应分子」，
16:33
that are being developed as new kinds of therapeutics.
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它们正作为新一代的疗法被开发研究中。
16:36
But then, to finish with a plug for all the good and miraculous bacteria
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为了鼓励地球上生存的
16:39
that live on the Earth,
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所有对人有益的细菌，
16:41
we've also made pro-quorum sensing molecules.
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我们也制造了「强化聚量感应分子」。
16:43
So, we've targeted those systems to make the molecules work better.
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因此，我们已经锁定了这些系统，让这些分子运作得更好。
16:46
Remember you have these 10 times or more bacterial cells
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请记得在你体内体表，有超过你自身细胞十倍的细菌，
16:50
in you or on you, keeping you healthy.
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它们使你保持健康。
16:52
What we're also trying to do is to beef up the conversation
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我们也努力加强
16:55
of the bacteria that live as mutualists with you,
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你和你的共生的细菌之间交流，
16:58
in the hopes of making you more healthy,
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让你更健康，
17:00
making those conversations better,
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让这种互动更有益。
17:02
so bacteria can do things that we want them to do
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让细菌只做我们希望它们做的事情。
17:05
better than they would be on their own.
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防止细菌做我们不希望它们做的事情。
17:08
Finally, I wanted to show you
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最后，我希望让你们看看
17:10
this is my gang at Princeton, New Jersey.
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我在新泽西，普林斯顿大学实验室的成员。
17:12
Everything I told you about was discovered by someone in that picture.
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我今天所告诉你们的每一个发现，都是由照片中的某人所完成的。
17:16
I hope when you learn things,
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我希望当你们学到东西的同时
17:18
like about how the natural world works --
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比如：自然世界是怎样运作的，
17:20
I just want to say that whenever you read something in the newspaper
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我只是想说，任何时候，当你们在报纸上看到某事，
17:23
or you get to hear some talk about something ridiculous in the natural world
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或是你们听到某些有关自然的，好玩事情的演讲，
17:26
it was done by a child.
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都是由年轻人完成的。
17:28
Science is done by that demographic.
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科学是由这种年龄层的人所造就的。
17:30
All of those people are between 20 and 30 years old,
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这些二、三十岁的年轻人
17:34
and they are the engine that drives scientific discovery in this country.
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他们是推动这个国家科学发现的引擎。
17:38
It's a really lucky demographic to work with.
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我真的是非常幸运能与这群年轻人一起共事。
17:41
I keep getting older and older and they're always the same age,
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我自己在不断地变老，但他们却是始终不变，
17:44
and it's just a crazy delightful job.
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这真是一个美好得不能再好的工作。
17:47
I want to thank you for inviting me here.
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我要谢谢你们的邀请。
17:49
It's a big treat for me to get to come to this conference.
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非常荣幸能参加这个大会。
17:52
(Applause)
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掌声
17:57
Thanks.
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谢谢
17:58
(Applause)
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掌声
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