Ode to Peter Mitchell

Everyone knows about Watson & Crick and Albert Einstein and a few other famous scientists who have discovered something new.

But few people know Peter Mitchell and why he is more important than most other scientists.

Mitchell is one of a handful of scientists who really have changed the way we think about a subject—in this case how energy is produced in living cells [see PETER MITCHELL
AND CHEMIOSMOTIC THEORY]

Nick Lane has just published an article in New Scientist that highlights Mitchell's contribution to biochemistry. Not only did Peter Mitchell show us how chemical energy is produced in living cells, he also provided tremendous insight into how it must have worked when life first began [Was our oldest ancestor a proton-powered rock? ].

Here's the opening paragraphs of Nick Lane's excellent article. You really should read the whole thing—buy the magazine if you have to.

PETER MITCHELL was an eccentric figure. For much of his career he worked in his own lab in a restored manor house in Cornwall in the UK, his research funded in part by a herd of dairy cows. His ideas about the most basic process of life - how it gets energy - seemed ridiculous to his fellow biologists.

"I remember thinking to myself that I would bet anything that [it] didn't work that way," biochemist Leslie Orgel wrote of his meeting with Mitchell half a century ago. "Not since Darwin and Wallace has biology come up with an idea as counter-intuitive as those of, say, Einstein, Heisenberg and Schrödinger."

Over the following decades, however, it became clear that Mitchell was right. His vindication was complete when he won a Nobel prize in 1978. Even today, though, most biologists have yet to grasp the full implications of his revolutionary ideas - especially for the origin of life.

I wish this weren't so but I'm afraid the last statement is correct. It's not only biologists who fail to grasp the implications, there are even biochemists who don't understand chemiosmotic theory and don't teach it correctly in undergraduate courses.

Some of the most popular biochemistry textbooks didn't explain it properly until their most recent editions in 2006 and 2007. That's shocking.

Peter Mitchell deserves a lot more credit than he gets.

The molecule shown above is ubiquinone:cytochrome c oxidoreductase, also known as complex III [PDB 1PP9]. It is one of the most important enzymes in all of biology. It's structure provided the ultimate proof of chemiosmotic theory since it catalyzes the Q cycle, the key step in creating a proton gradient across a membrane [see Ubiquinone and the Proton Pump].

Every student who takes an introductory biochemistry course should be intimately familiar with this enzyme and how it works. In fact, if they're not, you can be sure that the biochemistry course was not taught properly.

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