JOANNE STUBBE: When I went to graduate school, which
was in the late 1960s, I didn't even
know what an enzyme was, because back in those days
I'd never had a biology course.
They didn't do biochemistry back in those days.
And I think I heard a lecture by Van Tamelen at Stanford.
He was interested in steroid structures, steroids
that have four rings and it's the basis for sex hormones
and for cholesterol biosynthesis.
They're all sort of made through a common biosynthetic pathway
that we don't really talk about.
These are these five carbon units
to form carbon-carbon bonds that I mentioned earlier.
Anyhow, what he showed was you could
take 30 carbon strung together in a linear form.
And then somehow these 30 carbons
folded up with one enzyme to form these four rings,
putting in eight asymmetric centers in a single step at pH7
in 100% yield.
Once I saw that, I said man I don't want to be a chemist.
If you could see how nature designed this,
and what is the basis for being able to make these molecules,
it was sort of mind boggling to me.
And I think enzymes are like that.
What they do is they've evolved for billions of years
to accelerate rates of reactions by factors as much as 10
to the 20th.
So that's really fast, like a bat out of hell.
And so nature has figured out how to control all of this.
But again, she has a limited repertoire
of reactions that she catalyzes, but she's extremely good at it.
And so understanding people have studied enzymes forever
because I'd like to understand the basic principles
of catalysis.
And then if you understood those,
can the chemist then take this understanding
and translate it into the bigger repertoire
of the periodic table you have to be able to do
these transformations?
So the mechanisms of rate acceleration,
which we talk about in some detail in a lecture, what
causes these catalysts to work, and the way you
describe how these catalysts work.
It doesn't matter whether you're using
a small inorganic molecule or small organic molecules
or a protein, the basic principles
and thinking about catalysis is exactly the same, except nature
has figured out how to do this better than anything man can
do.
But again, she's limited in terms.
She's had a billions of years to evolve these catalysts,
but then she's limited in the repertoire of reactions
that she needs to catalyze.
So how can you not think enzymes are cool?