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JOANNE STUBBE: When I went
to graduate school, which

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was in the late
1960s, I didn't even

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know what an enzyme was,
because back in those days

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I'd never had a biology course.

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They didn't do biochemistry
back in those days.

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And I think I heard a lecture
by Van Tamelen at Stanford.

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He was interested in
steroid structures, steroids

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that have four rings and it's
the basis for sex hormones

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and for cholesterol
biosynthesis.

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They're all sort of made through
a common biosynthetic pathway

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that we don't really talk about.

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These are these
five carbon units

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to form carbon-carbon bonds
that I mentioned earlier.

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Anyhow, what he
showed was you could

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take 30 carbon strung
together in a linear form.

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And then somehow
these 30 carbons

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folded up with one enzyme
to form these four rings,

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putting in eight asymmetric
centers in a single step at pH7

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in 100% yield.

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Once I saw that, I said man
I don't want to be a chemist.

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If you could see how
nature designed this,

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and what is the basis for being
able to make these molecules,

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it was sort of mind
boggling to me.

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And I think enzymes
are like that.

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What they do is they've
evolved for billions of years

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to accelerate rates of reactions
by factors as much as 10

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to the 20th.

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So that's really fast,
like a bat out of hell.

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And so nature has figured out
how to control all of this.

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But again, she has
a limited repertoire

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of reactions that she catalyzes,
but she's extremely good at it.

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And so understanding people
have studied enzymes forever

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because I'd like to understand
the basic principles

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of catalysis.

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And then if you
understood those,

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can the chemist then
take this understanding

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and translate it into
the bigger repertoire

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of the periodic table
you have to be able to do

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these transformations?

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So the mechanisms of
rate acceleration,

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which we talk about in some
detail in a lecture, what

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causes these catalysts
to work, and the way you

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describe how these
catalysts work.

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It doesn't matter
whether you're using

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a small inorganic molecule
or small organic molecules

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or a protein, the
basic principles

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and thinking about catalysis is
exactly the same, except nature

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has figured out how to do this
better than anything man can

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do.

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But again, she's
limited in terms.

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She's had a billions of years
to evolve these catalysts,

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but then she's limited in
the repertoire of reactions

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that she needs to catalyze.

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So how can you not
think enzymes are cool?