(Piano)
The piece of music we are listening to
is Chopin’s Nocturne, Opus 55, No. 1.
I say that for those who did not recognize it,
but don't worry, I didn't know either.
We are in a magnificent auditorium, Massy's Opera theater,
and it is quite natural to listen to such piece of music in such a place.
But there is still a question you're asking yourself ... I can feel it.
And this question is
"what is the relationship between this Chopin's Nocturne
and the image that is currently projected on the screen
during the broadcast of this melody?"
This mage represents - of course, this time, you did recognize it -
a magnificent sculpture of the famous double helix of the DNA molecule,
DNA being the physical and molecular support
of our genetic and hereditary heritage.
So to answer this question and satisfy somewhat your legitimate curiosity,
I will start by telling you a little story
but a real story.
Once upon a time, there was a great scientist,
an American, who was also Japanese, called Susumo Ohno.
He was a great specialist in the study of the evolution of living organisms
at the genetic and molecular levels.
He hypothesized in his work that repetitions -
and I insist on the word "repetition" because words are important -
the repetitions of genetic information in DNA sequences
could play a very important role in the evolution of living organisms.
And in his reflections, he drew a parallel between the repetitions
and recurrences of genetic information in the DNA sequence,
and the repetitions of musical themes that we find in musical scores.
After a lot of cogitations and reflections,
he developed a method that allowed him to discover,
hidden behind the sequence of a real gene
that codes for a real protein existing in mice but also in humans,
the Chopin nocturne, Op.55, No. 1 that we just listened to.
It is extraordinary
to discover such a musical resonance
hidden behind genetic and biological information!
In fact, to achieve this,
this researcher constantly navigated between two universes:
that of Science that he knew well,
and that of Art that he invited in his own field
to try to explain and understand the functioning of the living.
So today ladies and gentlemen,
I'd like to take you on a journey that allows you precisely
to go back and forth between varied artistic universes
and the world of biology - it makes sense since I'm a biologist.
So here is for example how scientists observe,
under the very high magnifications of an electron microscope,
a simple bacteria.
Ladies and gentlemen, let me introduce Her Majesty Escherichia coli,
the queen of the commensal bacteria of our intestines.
By itself, this E. Coli bacteria, as its close friends say,
represents more than 80% of the 100,000 billion
not of a thousand portholes as Captain Haddock would say,
but of the 100,000 billion microorganisms that colonize our intestines:
the famous microbiota.
Well, this image is indeed very interesting for scientists,
but for the general public, it does not mean much.
So we can use paint to represent it.
This was done by a great American scientist, David Goodsell.
And we can also use sculpture.
This is what was done by a great British artist, Luke Jerram,
who uses transparent blown glass sculpture.
These are two representations on the same theme
to show in a more general way the organization of this bacteria.
If we now descend to even smaller microorganisms such as viruses,
here is the influenza virus
and the AIDS virus,
two viruses you have to protect yourself from,
even if you have to do it in very different ways,
if you see what I mean.
(Laughter) I will not draw the picture!
Indeed, these images are full of information for scientists,
but for the general public it remains abstract.
So on our trip,
we're going to make a stopover in California at David Goodsel's,
and we're going to ask him
if he would like to paint these viruses for us.
He's very nice and he did it.
And on the return trip, we made a stopover in Bristol
at Luke Jerram's place
to ask him to represent these same microorganisms
with his blown glass sculpture technique.
He was also very nice and did it.
Here is the result: these are two variations on the same theme
to represent the global organization of these viruses, how they are made,
the arrangement of their components in an artistic way.
We can point out potential therapeutic targets
to fight against these pathogens which continue to afflict the world.
Now If we go down again in the scale of living things,
we're going to meet their organic components,
one of their organic component that are proteins.
The two other organic components of living things are of course
sugars and fat, but tonight,
on the eve of the culinary Christmas festivities,
we are not going to talk about upsetting issues!
(Laughter)
Here's how scientists see a protein.
This represents the tertiary structure or conformation of a protein,
or to put it simply, the spatial form of a protein.
This is the Green Fluorescent Protein (GFP)
that lives in an oceanic jellyfish
and emits a magnificent green light … organic,
that has nothing to do with what Sébastien was talking about earlier.
Well, this protein is widely used as a tool in scientific research.
It’s used as a lamp or lantern for some studies.
There is nothing like a sculpture to depict an object in space, right?
Since we're still in England, let's make a stopover in Sheffield
at the house of a Japanese artist who uses origami.
She was also very nice, she made a giant origami
of this fluorescent GFP protein.
It explains the overall organization of this protein,
the different parts organized in helices or in sheets
and how it works.
When we see this wonder, we can only ask the question:
how can a cell make a protein?
In other words, how are proteins made up at the molecular level?
To answer this question,
I'm not going to tell you a story like before,
rather, I invite you to do an exercise together
that will use music.
As you all know, to make music, you need 12 musical notes.
With these 12 notes, a genius composer may offer
a composition like this - a very interesting work -
and with the same 12 musical notes, another composer
may offer something completely different.
Different elements characterize or define a musical score.
Today we're going to deal with two of them.
The first element that characterizes a musical score
is the order in which the musical notes appear.
And the second element is the length of the score,
or in other words the total number of musical notes.
The top one lasts 4:05 with a few hundred notes.
The bottom one lasts more than an hour with thousands of notes,
but with always the same 12 elementary notes as fondation.
Now to create proteins,
cells are using exactly the same building principle
than the one we just saw for music.
To fabricate proteins,
a cell uses 20 elementary units called "amino acids".
These are small chemical molecules whose formula are known.
They have a name,
and scientists assign them a letter of the alphabet
for the sake of simplicity.
Now just like a musical score, a protein is composed
of the sequence of these amino acids in a very precise order,
and it contains a total number of amino acids
that is also very precise and specific to the 25,000 proteins
that you are all synthesizing in your human cells.
Once the protein is created, it organizes itself in space
to adopt a shape, a functional structure.
And it is thanks to this architecture that the protein can function.
This is what we call the "structure-function relationship".
There you have it!
Ah, I think some people on the right want to tell me something!
Go ahead, I'm listening.
"Tell me, Mister Mohammed ..."
"Please call me 'Momo,' everyone does it,
I don't mind at all, okay?" (Laughter)
... "if you assign a musical note to an amino acid,
it becomes possible to translate its sequence into a musical score."
Yes, that’s exactly what we’re going to do.
Ah, some people on the left disagree!
“Tell me, Mister Momo" - you see, it works every time! -
your story, it's all well and good,
but you told us that 12 musical notes are needed to make music
whereas you need 20 amino acids to make proteins.
So how do you get the perfect match
to apply what people on the right just proposed?
There’s a little flat note in this story, don't you think?”
I think the people on the left have paid more attention
to what I just said than the people on the right.
And please don’t see any political connotation here.
(Laughter)
Well, we as scientists have admittedly our heads in the clouds.
Like Professor Tournesol, we're a bit disorganized,
but when it comes to science, we like to classify things.
And we do it very rigorously.
So we classified amino acids into subgroups
because some have very similar physico-chemical properties.
For example, some are like fish: they love water;
so they are called "hydrophilic".
In contrast, others are like kitties: they have a water phobia.
In fact, I like to call them “pussycat acid”,
"hydrophobic" of course.
Others are a little excited, electric.
They have a negative or a positive charge, and so on.
By working to sort them out and classify them,
we easily obtain 12 amino acid groups
to which we assign a musical note, and that does the trick.
What is interesting in this story is that each of you here
or who are watching us in Senegal or Romania,
are free - and we are in the land of Liberty par excellence -
to assign the music note you want to this or that group of amino acids.
So each of you is able to create
his or her own musical score of such and such protein.
Now one day, or maybe it was one night,
(Laughter)
two Americans invited each other:
Marie-Anne Clarke, biologist, and John Dunn, computer scientist.
I don't know what they did that night or that day,
but what I do know is that from this meeting
is born not a baby but an algorithm
that is inspired by what we just saw.
This algorithm enables us to translate the amino acid sequence of any protein
into its equivalent in the musical score.
So we can discover ... the hemoglobin's symphony,
(Laughter)
the Insulin's blues, the Keratin's rock,
or the Collagen's swing, who knows?
Alright, if my story can be put in parentheses,
the opening one being the Chopin's Nocturn,
the closing one is also going to be a musical piece, that of a protein.
Its name is Spidroine.
Spidroine is the protein that makes up the threads of a spider's web.
I really like spiders.
And rest assured, I am not like Cédric Villani.
(Laughter)
Okay? You noticed I have no spider on the collar of my jacket,
nor bats in the belfry I hope!
Well,
be aware that this protein which the silk of the spider's web is made of,
represents the most resistant, the most solid, the most elastic,
and the lightest material in existence.
Imagine a spider making a single thread of its web
that would circle the Earth.
Well this simple wire would be 40,075 km long and weigh only 420 gr.
Its resistance and solidity is due to the repetitions
of specific amino acid sequences,
which we will also find in its musical equivalent.
So I invite you to close your eyes if you are afraid of spiders,
open your ears wide,
and imagine yourself on a beautiful clear night
listening to the musical resonance
of the protein of a web that a spider is weaving
under the moon light.
(Applause)
(Music)
(The music ends)
I hope after this you'll no longer see spiders the same way.
(Applause)
Thank you.
In conclusion, I hope what we saw together today
was a good illustration of the possible transversality between disciplines.
The meeting of one with the other enables knowledge to be shared
in a way, I hope, both educational and fun.
It also enables passions to be shared
as well as another way of looking at our own work and discipline.
And this ties in
with what the great French philosopher, poet and writer, Paul Valery, has said,
to whom I leave the last word with his quote:
"There was once someone who could look at the same object
with the eyes of a painter, or a naturalist,
with the eyes of a physicist at times and at other times of a poet,
and none of these looks was superficial."
None of these looks was superficial.
Thank you very much.
(Applause)