Bonnie Bassler: The secret, social lives of bacteria

Translator: Andrea Muras Reviewer: Xusto Rodriguez

As bacterias son os organismos máis antigos que viven na Terra.

Bacteria are the oldest living organisms on the earth.

They've been here for billions of years,

Levan aquí miles de millóns de anos

and what they are are single-celled microscopic organisms.

sendo organismos microscópicos unicelulares.

So they're one cell

Cada bacteria é unha única célula coa propiedade especial

and they have this special property that they only have one piece of DNA.

de ter soamente un fragmento de ADN

So they have very few genes and genetic information

Teñen moi poucos xenes,

e esta información xénica codifica todas as súas funcións.

to encode all of the traits that they carry out.

And the way bacteria make a living is that they consume nutrients

As bacterias viven do seguinte xeito:

consomen nutrientes do medio,

from the environment,

they grow to twice their size,

crecen dobrando o seu tamaño, córtanse pola metade,

they cut themselves down in the middle,

unha célula convértese en dúas, e así unha e outra vez.

and one cell becomes two, and so on and so on.

They just grow and divide and grow and divide -- so a kind of boring life,

Crecen e divídense, crecen e divídense --é unha vida aburrida--

except that what I would argue is that you have an amazing interaction

excepto porque vostedes teñen

unhas interaccións incribles con estes bichos.

with these critters.

I know you guys think of yourself as humans,

Vós védesvos como humanos, e en parte é o que penso de vós.

and this is sort of how I think of you.

Este home representa supostamente

This man is supposed to represent a generic human being,

un ser humano tipo,

and all of the circles in that man are all the cells that make up your body.

e cada círculo nel é unha célula que forma o seu corpo.

There's about a trillion human cells that make each one of us who we are

Hai arredor dun billón de células humanas que fan de nós

quen somos e permítennos facer o que facemos,

and able to do all the things that we do.

pero vostedes teñen 10 billóns de células bacterianas

But you have 10 trillion bacterial cells in you or on you

dentro ou encima, en calquera intre da súa vida.

at any moment in your life.

So, 10 times more bacterial cells than human cells on a human being.

Hai 10 veces máis células bacterianas

que células humanas nun ser humano.

And, of course, it's the DNA that counts,

E por suposto é o ADN o que conta,

so here's all the A, T, Gs and Cs that make up your genetic code

aquí temos todos os A, T, G e C

que forman os xenes, responsables das súas peculiaridades.

and give you all your charming characteristics.

Vostedes teñen sobre 30.000 xenes.

You have about 30,000 genes.

Well, it turns out you have 100 times more bacterial genes

Ben, pois teñen 100 veces máis xenes bacterianos

que xogan un papel en ou sobre vostedes durante toda a vida.

playing a role in you or on you all of your life.

So at the best, you're 10 percent human; more likely, about one percent human,

No mellor dos casos, son un 10% humanos,

pero máis probablemente só un 1%,

depending on which of these metrics you like.

dependendo do parámetro que prefiran.

I know you think of yourself as human beings,

Sei que se consideran seres humanos,

pero eu penso en vostedes como en bacterias nun 90 ou 99%.

but I think of you as 90 or 99 percent bacterial.

(Laughter)

(Risas)

And these bacteria are not passive riders.

Estas bacterias non son pasaxeiros pasivos,

These are incredibly important; they keep us alive.

son moi importantes, mantéñennos vivos.

They cover us in an invisible body armor

Cóbrennos cunha armadura invisible

that keeps environmental insults out so that we stay healthy.

que nos protexe do contorno

manténdonos así sans.

They digest our food, they make our vitamins,

Dixiren a nosa comida, producen vitaminas,

they actually educate your immune system to keep bad microbes out.

educan o noso sistema inmune

para impedir a entrada dos microbios nocivos.

Fan todas estas cousas incribles

So they do all these amazing things

que nos axudan e son vitais para manternos vivos,

that help us and are vital for keeping us alive,

and they never get any press for that.

e nunca nos acordamos delas por iso.

But they get a lot of press because they do a lot of terrible things as well.

Pero si que nos acordamos por facer

cousas terribles.

Sobre a Terra existen moitos tipos de bacterias

So there's all kinds of bacteria on the earth

that have no business being in you or on you at any time,

que mellor que non estean nunca en ou sobre vostedes,

pois se están, poñeríanse moi enfermos.

and if they are, they make you incredibly sick.

And so the question for my lab

Por isto, a pregunta no meu laboratorio non é pensar

is whether you want to think about all the good things that bacteria do

en todas as cousas boas ou malas que as bacterias fan.

or all the bad things that bacteria do.

A pregunta que nos formulamos é como poden facer algo?

The question we had is: How could they do anything at all?

Quero dicir: son incriblemente pequenas,

I mean, they're incredibly small.

You have to have a microscope to see one.

necesítase un microscopio para velas.

They live this sort of boring life where they grow and divide,

Viven esta vida aburrida onde só crecen e se dividen

and they've always been considered to be these asocial, reclusive organisms.

e sempre foron consideradas organismos asociais e solitarios.

And so it seemed to us that they're just too small

Ademais parécenos que son pequenas de máis

to have an impact on the environment

para influír sobre o medio

if they simply act as individuals.

se actúan unicamente como individuos.

So we wanted to think if there couldn't be a different way that bacteria live.

E así, demos en pensar se podería ser

que as bacterias vivisen de forma distinta

A clave para isto veu doutra bacteria mariña,

And the clue to this came from another marine bacterium,

and it's a bacterium called "Vibrio fischeri."

chamada Vibrio fischeri.

What you're looking at on this slide is just a person from my lab

O que vedes nesta diapositiva é unha persoa do meu laboratorio

holding a flask of a liquid culture of a bacterium,

termando dun matraz co cultivo líquido da bacteria,

esta inofensiva e fermosa bacteria procede do océano,

a harmless, beautiful bacterium that comes from the ocean,

chámase Vibrio fischeri.

named Vibrio fischeri.

And this bacterium has the special property that it makes light,

E ten a propiedade especial de que produce luz,

produce bioluminiscencia,

so it makes bioluminescence,

like fireflies make light.

igual ca os vagalumes.

We're not doing anything to the cells here,

Non lles estamos a facer nada ás células.

we just took the picture by turning the lights off in the room,

Só tiramos a foto coas luces apagadas,

e velaí o que se ve.

and this is what we see.

And what's actually interesting to us was not that the bacteria made light

O que é realmente interesante para nós

non é que as bacterias produzan luz,

but when the bacteria made light.

senón cando a producen.

What we noticed is when the bacteria were alone,

Detectamos que cando as bacterias están soas

so when they were in dilute suspension,

é dicir, cando están nunha suspensión diluída , non fan luz.

they made no light.

Pero ao acadaren un certo número

But when they grew to a certain cell number,

todas elas "acéndense" á vez.

all the bacteria turned on light simultaneously.

So the question that we had is:

E preguntámonos como as bacterias, estes organismos primitivos,

How can bacteria, these primitive organisms,

saben cando están soas,

tell the difference from times when they're alone

e cando se atopan en comunidade,

and times when they're in a community,

e entón comezan a facer algo xuntas.

and then all do something together?

O que descubrimos é que fan todo isto falando unhas coas outras,

And what we figured out is that the way they do that is they talk to each other,

e que falan usando unha linguaxe química.

and they talk with a chemical language.

Supoñamos que isto é a miña célula bacteriana.

So this is now supposed to be my bacterial cell.

Cando está soa non fai luz.

When it's alone, it doesn't make any light.

But what it does do is to make and secrete small molecules

pero si produce e segrega unhas pequenas moléculas

that you can think of like hormones,

que actúan como as hormonas (son estes triángulos vermellos),

and these are the red triangles.

And when the bacteria are alone, the molecules just float away,

as moléculas só flotan e non hai luz.

and so, no light.

But when the bacteria grow and double

Pero cando as bacteria aumentan

and they're all participating in making these molecules,

e todas producen estas moléculas,

a molécula (a cantidade extracelular dela)

the molecule, the extracellular amount of that molecule,

increases in proportion to cell number.

aumenta proporcionalmente ao número de células.

And when the molecule hits a certain amount

E cando a molécula chega a unha certa cantidade

that tells the bacteria how many neighbors there are,

que lle indica ás bacterias cantas veciñas están aí,

they recognize that molecule

elas recoñecen a molécula

and all of the bacteria turn on light in synchrony.

e todas producen luz en sincronía.

And so that's how bioluminescence works --

Así funciona a bioluminiscencia,

they're talking with these chemical words.

elas falan con palabras químicas.

A razón pola que Vibrio fischeri o fai procede da bioloxía.

The reason Vibrio fischeri is doing that comes from the biology --

again, another plug for the animals in the ocean.

Máis publicidade para os animais do océano,

Vibrio fischeri vive dentro desta lura.

Vibrio fischeri lives in this squid.

What you're looking at is the Hawaiian bobtail squid.

Velaquí a lura hawaiana de rabo curto,

que está virado de costas,

It's been turned on its back,

and what I hope you can see are these two glowing lobes.

e espero que poidades ver estes dous lóbulos relucentes

These house the Vibrio fischeri cells.

que acollen as células de Vibrio fischeri,

They live in there, at high cell number.

elas viven aí,

That molecule is there, and they're making light.

a molécula atópase aí, e están producindo luz.

And the reason the squid is willing to put up with these shenanigans

A razón pola que a lura está disposta a aturar estes diaños

is because it wants that light.

é porque quere esa luz.

The way that this symbiosis works

A simbiose funciona así:

is that this little squid lives just off the coast of Hawaii,

a lura vive cerca da costa de Hawai

just in sort of shallow knee-deep water.

en augas tranquilas e pouco profundas.

And the squid is nocturnal,

É nocturna, polo que durante o día

so during the day, it buries itself in the sand and sleeps.

sotérrase na area e dorme;

pero de noite sae de caza.

But then at night, it has to come out to hunt.

So on bright nights

Nas noites claras, de luar ou estreladas

when there's lots of starlight or moonlight,

esa luz pode penetrar ata a profundidade

that light can penetrate the depth of the water the squid lives in,

onde vive a lura, apenas un metro de auga.

since it's just in those couple feet of water.

A lura desenvolveu un obturador

What the squid has developed is a shutter that can open and close

que abre e pecha o órgano luminoso que acolle as bacterias.

over the specialized light organ housing the bacteria.

Ten uns sensores no lombo

And then it has detectors on its back

que detectan canta claridade lle chega a el.

so it can sense how much starlight or moonlight is hitting its back.

And it opens and closes the shutter

O obturador abre ou pecha

so the amount of light coming out of the bottom,

de modo que a luz emitida pola parte inferior

which is made by the bacterium,

--que é producida pola bacteria--

exactly matches how much light hits the squid's back,

é a mesma que chega ao lombo da lura,

so the squid doesn't make a shadow.

e así, a lura non produce sombra.

So it actually uses the light from the bacteria

De feito, usa a luz das bacterias

to counter-illuminate itself in an antipredation device,

para contrailuminarse como un mecanismo antipredación

xa que os predadores non poden ver a súa sombra,

so predators can't see its shadow,

calcular a súa traxectoria, e comela.

calculate its trajectory and eat it.

So this is like the stealth bomber of the ocean.

Como se fose o bombardeiro furtivo do océano.

(Laughter)

(Risas)

But then if you think about it, this squid has this terrible problem,

Pero se pensades nisto, a lura ten un terrible problema

porque ten un gran cultivo de bacterias moribundas

because it's got this dying, thick culture of bacteria,

and it can't sustain that.

que non pode manter continuamente.

And so what happens is, every morning when the sun comes up,

O que fai é que, cada maña cando sae o sol

a lura volve durmir, sotérrase na area,

the squid goes back to sleep, it buries itself in the sand,

e ten unha bomba ligada ao seu ritmo circadiano,

and it's got a pump that's attached to its circadian rhythm.

And when the sun comes up, it pumps out, like, 95 percent of the bacteria.

e cando alborece expele o 95% das bacterias.

So now the bacteria are dilute,

Agora as bacterias están diluídas, non hai moléculas abondas,

that little hormone molecule is gone, so they're not making light.

así que elas non producen luz,

But, of course, the squid doesn't care, it's asleep in the sand.

pero á lura élle igual. Está durmindo na area.

Ao longo do día as bacterias duplícanse,

And as the day goes by, the bacteria double,

liberan a molécula, e a luz acéndese

they release the molecule, and then light comes on at night,

de noite, exactamente cando a lura quere.

exactly when the squid wants it.

So first, we figured out how this bacterium does this,

Primeiro descubrimos como facía isto a bacteria,

but then we brought the tools of molecular biology to this

logo empregamos as ferramentas da bioloxía molecular

to figure out, really, what's the mechanism.

para descifrar como é de verdade o mecanismo.

And what we found -- so this is now supposed to be my bacterial cell --

E o que atopamos --supoñamos que esta é outra vez a miña bacteria--

is that Vibrio fischeri has a protein.

é que Vibrio fischeri ten una proteína

That's the red box --

--a caixa vermella--, é un enzima que produce

it's an enzyme that makes that little hormone molecule,

esa pequena molécula --o triángulo vermello.

the red triangle.

And then as the cells grow,

Mentres as células crecen liberan a molécula

they're all releasing that molecule into the environment,

ao medio ambiente, polo que hai moitas moléculas.

so there's lots of molecule there.

E a célula tamén ten un receptor na súa superficie celular

And the bacteria also have a receptor on their cell surface

that fits like a lock and key with that molecule.

que encaixa coa molécula coma unha chave nunha pechadura

These are just like the receptors on the surfaces of your cells.

Son xusto coma os receptores da superficie das vosas células.

Cando a molécula aumenta ata certa cantidade

So when the molecule increases to a certain amount,

which says something about the number of cells,

--o que ten relación co número de células--

it locks down into that receptor

encaixa no receptor

and information comes into the cells

e a información entra nas células

para dicirlle a estas que activen

that tells the cells to turn on this collective behavior of making light.

o comportamento colectivo de facer luz.

Why this is interesting is because in the past decade,

Isto é interesante porque na década pasada

we have found that this is not just some anomaly

atopamos que non é unha anomalía

of this ridiculous, glow-in-the-dark bacterium that lives in the ocean --

desta ridícula bacteria brillante que vive no océano:

todas as bacterias teñen sistemas semellantes a esta.

all bacteria have systems like this.

So now what we understand is that all bacteria can talk to each other.

Agora entendemos que todas as bacterias falan unhas con outras.

They make chemical words, they recognize those words,

Emiten unhas palabra químicas, recoñécenas,

and they turn on group behaviors

e activan o comportamento grupal

that are only successful when all of the cells participate in unison.

que só ten éxito cando as células cooperan ao unísono.

So now we have a fancy name for this: we call it "quorum sensing."

Nós chamámoslle a isto "percepción do quórum"

They vote with these chemical votes,

Elas votan con eses votos químicos,

the vote gets counted, and then everybody responds to the vote.

os votos cóntanse, e logo todo o mundo responde ao resultado.

What's important for today's talk is we know there are hundreds of behaviors

O máis importante da charla de hoxe

é que sabemos que hai centos de condutas

that bacteria carry out in these collective fashions.

que as bacterias executan de xeito colectivo.

But the one that's probably the most important to you is virulence.

Mais, probablemente o máis importante para vós é a virulencia.

Non é que un par de bacterias entren en vós

It's not like a couple bacteria get in you and start secreting some toxins --

e comecen a segregar toxinas

you're enormous; that would have no effect on you, you're huge.

--vós sodes enormes-- que non vos farían efecto ningún.

O que fan, agora o entendemos,

But what they do, we now understand,

is they get in you, they wait, they start growing,

é entrar en vós, esperar, empezar a crecer,

they count themselves with these little molecules,

recontarse coas moléculas

and they recognize when they have the right cell number

e recoñecer cando son o número abondo

para --se lanzan xuntas o seu ataque virulento--

that if all of the bacteria launch their virulence attack together,

they're going to be successful at overcoming an enormous host.

teren éxito ao bater a un enorme anfitrión.

So bacteria always control pathogenicity with quorum sensing.

As bacterias sempre controlan a patoxenicidade coa percepción do quórum

So that's how it works.

Así funcionan.

Tamén observamos que son estas moléculas

We also then went to look at what are these molecules.

These were the red triangles on my slides before.

--estes son os triángulos vermellos nas miñas diapositivas.

This is the Vibrio fischeri molecule.

Esta é a molécula de Vibrio fischeri.

This is the word that it talks with.

Esta é a palabra con que se comunica.

And then we started to look at other bacteria,

Entón comezamos a observar outras bacterias,

and these are just a smattering of the molecules that we've discovered.

e estas son só unha mostra das moléculas que atopamos.

O que espero que poidan ver

What I hope you can see is that the molecules are related.

é que as moléculas están relacionadas.

The left-hand part of the molecule is identical

A parte esquerda da molécula é idéntica

in every single species of bacteria.

en todas as especies de bacteria.

But the right-hand part of the molecule is a little bit different

Mais a parte dereita é un chisco diferente en cada especie.

in every single species.

O que lle confire

What that does is to confer exquisite species specificities to these languages.

unha especificidade exquisita a estas linguaxes.

So each molecule fits into its partner receptor

Cada molécula encaixa no seu receptor e non noutro.

and no other.

Polo que estas son conversacións privadas, secretas.

So these are private, secret conversations.

These conversations are for intraspecies communication.

Estas conversacións son para comunicarse dentro da mesma especie.

Each bacteria uses a particular molecule that's its language

Cada bacteria usa a súa molécula que é a súa linguaxe

that allows it to count its own siblings.

que lle permite contar as súas irmás.

Once we got that far,

Cando chegamos ata aquí pensamos

we thought we were starting to understand that bacteria have these social behaviors.

que comezamos a entender que as bacterias teñen condutas sociais.

But what we were really thinking about is that most of the time,

Mais o que de verdade pensabamos é que a maior parte do tempo

bacteria don't live by themselves, they live in incredible mixtures,

as bacterias non viven soas, viven en mesturas incribles,

with hundreds or thousands of other species of bacteria.

con centos ou miles doutras especies de bacterias.

And that's depicted on this slide.

É o que se representa nesta diapositiva. Esta é a súa pel.

This is your skin.

So this is just a picture -- a micrograph of your skin.

Isto é soamente unha imaxe --unha micrografía da súa pel.

Anywhere on your body, it looks pretty much like this.

Calquera lugar do corpo, parécese moito a isto,

e espero que poidan ver que aí hai todo tipo de bacterias.

What I hope you can see

is that there's all kinds of bacteria there.

And so we started to think, if this really is about communication in bacteria,

Entón, comezamos a pensar que se realmente a comunicación entre bacterias

and it's about counting your neighbors,

ten que ver con contar os veciños,

it's not enough to be able to only talk within your species.

non abonda con falar só cos da túa especie.

Ten que existir un xeito de censar

There has to be a way to take a census

ao resto de bacterias na poboación.

of the rest of the bacteria in the population.

So we went back to molecular biology

Polo que volvemos á bioloxía molecular

and started studying different bacteria.

e comezamos a estudar diferentes bacterias,

And what we've found now is that, in fact, bacteria are multilingual.

e o que atopamos agora foi que

en realidade, as bacterias son políglotas.

They all have a species-specific system,

Todas teñen un sistema específico por especie

--unha molécula que di "eu".

they have a molecule that says "me."

But then running in parallel to that is a second system

Pero vai en paralelo a un segundo sistema

that we've discovered, that's generic.

que descubrimos, que é xenérico.

So they have a second enzyme that makes a second signal,

Elas teñen un segundo enzima que fai un segundo sinal

and it has its own receptor,

e ten o seu propio receptor,

and this molecule is the trade language of bacteria.

e esta molécula é a lingua internacional das bacterias.

Todas a empregan

It's used by all different bacteria,

e é a lingua de comunicación entre especies.

and it's the language of interspecies communication.

What happens is that bacteria are able to count

As bacterias son capaces de contar

cantos "eu" e cantos "ti" hai.

how many of "me" and how many of "you."

And they take that information inside,

Elas recollen esa información,

and they decide what tasks to carry out

e deciden que tarefas fan

dependendo de quen estea en minoría e quen en maioría

depending on who's in the minority and who's in the majority

of any given population.

dunha poboación determinada.

Then, again, we turned to chemistry,

Outra vez voltamos a química,

and we figured out what this generic molecule is --

e atopamos que esta molécula xenérica é

that was the pink ovals on my last slide, this is it.

--son os óvalos rosas da miña última diapositiva--

It's a very small, five-carbon molecule.

é moi pequena, unha molécula de 5 átomos de carbonos.

And what the important thing is that we learned

O importante é que aprendemos

is that every bacterium has exactly the same enzyme

que cada bacteria ten exactamente o mesmo enzima

and makes exactly the same molecule.

e fai exactamente a mesma molécula.

So they're all using this molecule for interspecies communication.

Todas usan esta molécula

para comunicarse entre especies.

This is the bacterial Esperanto.

Velaquí o esperanto bacteriano.

(Laughter)

(Risas)

So once we got that far,

Chegados ata aquí, comezamos a comprender

we started to learn that bacteria can talk to each other

que as bacterias falan entre si con esta linguaxe química.

with this chemical language.

Pero comezamos a pensar se haberá

But we started to think

that maybe there is something practical that we can do here as well.

algo práctico que poidamos facer aquí.

Díxenlles que as bacterias teñen todas estas condutas sociais,

I've told you that bacteria have all these social behaviors,

que se comunican con estas moléculas.

that they communicate with these molecules.

Of course, I've also told you that one of the important things they do

Tamén lles dixen que una das cousas máis importantes que fan

é iniciar a patoxenicidade usando a percepción do quórum.

is to initiate pathogenicity using quorum sensing.

Nós pensamos, e se facemos que as bacterias

So we thought:

What if we made these bacteria so they can't talk or they can't hear?

non poidan falar ou escoitar?

Non podería ser un novo tipo de antibiótico?

Couldn't these be new kinds of antibiotics?

And of course, you've just heard and you already know

Seguro que xa escoitastes e sabedes

que estamos quedando sen antibióticos.

that we're running out of antibiotics.

Neste momento, as bacterias son incriblemente resistentes,

Bacteria are incredibly multi-drug-resistant right now,

and that's because all of the antibiotics that we use kill bacteria.

porque os antibióticos que usamos matan as bacterias.

They either pop the bacterial membrane,

Rebentan a membrana bacteriana,

they make the bacterium so it can't replicate its DNA.

ou fan que a bacteria non poida replicar o seu ADN.

We kill bacteria with traditional antibiotics,

Cos antibióticos tradicionais, nós matamos as bacterias,

and that selects for resistant mutants.

o que selecciona as mutacións resistentes.

And so now, of course, we have this global problem

E así, agora temos este problema global

in infectious diseases.

de enfermidades infecciosas.

So we thought, what if we could sort of do behavior modifications,

Nós pensamos: e se puideramos cambiar dalgún modo o seu comportamento,

just make these bacteria so they can't talk, they can't count,

facenr que estas bacterias non poidan falar ou contar,

e así, tampouco producir virulencia?

and they don't know to launch virulence?

So that's exactly what we've done,

E fixemos exactamente iso, empregando dúas estratexias.

and we've sort of taken two strategies.

A primeira tivo como obxectivo

The first one is, we've targeted the intraspecies communication system.

o sistema de comunicación dentro da mesma especie.

So we made molecules that look kind of like the real molecules, which you saw,

Fixemos moléculas similares ás moléculas reais

--velaquí as tedes-- mais un chisco distintas.

but they're a little bit different.

Encaixan nos receptores,

And so they lock into those receptors,

e bloquean o recoñecemento da molécula real.

and they jam recognition of the real thing.

So by targeting the red system,

Poñendo como obxectivo o sistema vermello

what we are able to do is make species-specific, or disease-specific,

somos capaces de obter moleculas antipercepción do quórum

específicas para especies ou para enfermidades.

anti-quorum-sensing molecules.

We've also done the same thing with the pink system.

Tamén fixemos o mesmo co sistema rosa.

We've taken that universal molecule and turned it around a little bit

Collemos a molécula universal e cambiámoslle un fragmento,

so that we've made antagonists of the interspecies communication system.

co que obtivemos antagonistas

do sistema de comunicación entre especies.

A esperanza é que isto poida empregarse como antibióticos de amplo espectro

The hope is that these will be used as broad-spectrum antibiotics

that work against all bacteria.

que funcionen contra todas as bacterias.

And so to finish, I'll show you the strategy.

Para rematar, déixenme amosarlles a estratexia.

In this one, I'm just using the interspecies molecule,

Nesta emprego unha molécula interespecie.

but the logic is exactly the same.

pero a lóxica é a mesma.

So what you know is that when that bacterium gets into the animal --

O que sabemos é que cando unha bacteria entra nun animal,

neste caso, un rato,

in this case, a mouse --

it doesn't initiate virulence right away.

non comeza a virulencia inmediatamente.

It gets in, it starts growing,

Entra, comeza a medrar, empeza a segregar

it starts secreting its quorum-sensing molecules.

as moléculas de percepción do quórum.

It recognizes when it has enough bacteria

Recoñece cando hai bacterias abondas

that now they're going to launch their attack,

e entón lanzan o seu ataque,

e o animal morre.

and the animal dies.

And so what we've been able to do is to give these virulent infections,

O que fixemos foi producir estas infeccións virulentas,

but we give them in conjunction with our anti-quorum-sensing molecules.

pero engadindo moléculas antipercepción do quórum

So these are molecules that look kind of like the real thing,

--estas moléculas seméllanse ás reais,

pero son algo diferentes, como se ve na diapositiva.

but they're a little different, which I've depicted on this slide.

Agora sabemos que se tratamos o animal

What we now know is that if we treat the animal with a pathogenic bacterium --

cunha bacteria patóxena --unha bacteria multirresistente--

a multi-drug-resistant pathogenic bacterium --

in the same time we give our anti-quorum-sensing molecule,

ao mesmo tempo que lle damos moléculas antipercepción do quórum,

in fact, the animal lives.

de feito, o animal vive.

And so we think that this is the next generation of antibiotics,

Nós pensamos que esta é a próxima xeración de antibióticos

and it's going to get us around, at least initially,

e vainos permitir superar, polo menos inicialmente,

this big problem of resistance.

este gran problema da resistencia.

What I hope you think is that bacteria can talk to each other,

O que espero que entendan é que as bacterias falan entre elas,

usan substancias químicas como palabras,

they use chemicals as their words,

they have an incredibly complicated chemical lexicon

teñen un léxico químico incriblemente complexo

that we're just now starting to learn about.

que agora estamos comezando a aprender.

De feito, isto permítelles actuar

Of course, what that allows bacteria to do is to be multicellular.

como se fosen pluricelulares.

So in the spirit of TED,

Seguindo o espírito de TED elas fan cousas xuntas

they're doing things together because it makes a difference.

porque iso marca a diferenza.

E así, as bacterias teñen esas condutas colectivas,

What happens is that bacteria have these collective behaviors,

and they can carry out tasks

e levan a cabo tarefas

that they could never accomplish if they simply acted as individuals.

que nunca poderían facer

se actuasen só como individuos.

What I would hope that I could further argue to you

O que me gustaría defender

é que isto é a invención de pluricelularidade.

is that this is the invention of multicellularity.

Bacteria have been on the earth for billions of years;

As bacterias levan na Terra miles de millóns de anos;

humans, couple hundred thousand.

os seres humanos, uns douscentos mil.

So we think bacteria made the rules for how multicellular organization works.

Cremos que as bacterias estableceron as regras

sobre como funciona a organización pluricelular.

Pensamos que, estudando as bacterias,

And we think by studying bacteria,

we're going to be able to have insight about multicellularity in the human body.

coñeceremos máis sobre a pluricelularidade no corpo humano.

So we know that the principles and the rules,

Sabemos que, se entendemos os principios e as regras,

if we can figure them out in these sort of primitive organisms,

nestes organismos primitivos,

é posible que os poidamos aplicar

the hope is that they will be applied

a outras enfermidades e condutas humanas.

to other human diseases and human behaviors as well.

Espero que aprenderan

I hope that what you've learned

is that bacteria can distinguish self from other.

que as bacterias poden distinguirse unhas das outras.

So by using these two molecules,

Usando esas dúas moléculas poden dicir "eu" ou "ti".

they can say "me" and they can say "you."

And again, of course, that's what we do,

Unha vez máis, iso é o que facemos,

nunha forma molecular,

both in a molecular way, and also in an outward way,

e nunha forma externa,

but I think about the molecular stuff.

pero eu interésome pola parte molecular.

This is exactly what happens in your body.

Isto é o que pasa no seu corpo.

It's not like your heart cells and kidney cells get all mixed up every day,

As células do corazón e as dos riles nunca se mesturan,

and that's because there's all of this chemistry going on,

grazas a todos estes procesos químicos,

these molecules that say who each of these groups of cells is

a estas moléculas que din que células son de cada grupo,

e que tarefas debe realizar cada un.

and what their tasks should be.

So again, we think bacteria invented that,

Outra vez, cremos que iso o inventaron as bacterias,

and you've just evolved a few more bells and whistles,

e vostedes evolucionaron un pouco máis,

but all of the ideas are in these simple systems that we can study.

pero todas as ideas están nestes sistemas simples que podemos estudar.

And the final thing is, just to reiterate that there's this practical part,

Por último, reiterar que isto ten unha vertente práctica,

and so we've made these anti-quorum-sensing molecules

e que fixemos estas moléculas antipercepción do quórum

that are being developed as new kinds of therapeutics.

que están sendo desenvolvidas como novos tipos de terapia.

But then, to finish with a plug for all the good and miraculous bacteria

Para rematar un recoñecemento a todas as boas e incribles bacterias

that live on the earth,

que viven na Terra,

we've also made pro-quorum-sensing molecules.

que fan moléculas propercepción do quórum.

So we've targeted those systems to make the molecules work better.

Modificamos os sistemas para facer que as moléculas funcionen mellor.

So remember, you have these 10 times or more bacterial cells

Lembren que teñen 10 veces máis células bacterianas

in you or on you, keeping you healthy.

en ou sobre vostedes, manténdoos sans.

What we're also trying to do is to beef up the conversation

Tamén estamos a tratar de fortalecer a conversación

das bacterias que viven como mutualistas con vostedes,

of the bacteria that live as mutualists with you,

in the hopes of making you more healthy,

coa esperanza de facelos máis sans,

mellorando esas conversacións,

making those conversations better,

so bacteria can do things that we want them to do

para que as bacterias poidan facer cousas que nos interesen

better than they would be on their own.

mellor do que o farían por si mesmas.

Finally, I wanted to show you --

Para rematar, quero mostrarlles

this is my gang at Princeton, New Jersey.

o meu grupo en Princeton, Nova Jersey.

Everything I told you about was discovered by someone in that picture.

Todo o que lles contei descubriuno alguén desta foto.

Espero que cando aprendan cousas,

And I hope when you learn things, like about how the natural world works --

por exemplo, como funciona o mundo natural

I just want to say that whenever you read something in the newspaper

--cando lea algo no xornal

or you hear some talk about something ridiculous in the natural world,

ou oia algunha conversa sobre algo ridículo no mundo natural

pode que o fixese un rapaz.

it was done by a child.

So science is done by that demographic.

A ciencia faina este grupo de idade.

All of those people are between 20 and 30 years old,

Todos teñen entre 20 e 30 anos,

and they are the engine that drives scientific discovery in this country.

e son o motor que move os descubrimentos científicos neste país.

And it's a really lucky demographic to work with.

É unha sorte traballar con eles.

(Applause)

Eu son cada vez máis vella e eles sempre teñen a mesma idade,

I keep getting older and older, and they're always the same age.

e é simplemente un traballo tolo e esgotador.

And it's just a crazy, delightful job.

And I want to thank you for inviting me here,

Quero darlles as grazas por invitarme.

it's a big treat for me to get to come to this conference.

É un gran pracer para min asistir a esta conferencia

(Applause)

(Aplausos)

Thanks.

Grazas.

(Applause)

(Aplausos)