The Michaelis-Menten Equation
A story about love, and the equation that love created
August 10, 2005
Mention the phrase “Michaelis-Menten Equation” to any physician or medical student, and you’re likely to get a blank stare, or perhaps a disinterested shrug. Not only does the equation seem irrevelant to the clinical practice of medicine, but, to many, the mere thought of it conjures up unpleasant memories of first-year Biochemistry final examinations.
What many fail to realize, though, is the rich history behind the equation, and the fascinating events that led to its development. As always, the real story is much more complicated ... and INTERESTING! |
In 1903, Mexico City was a hotbed of scientific
inquiry, attracting researchers from all over the world to its beautiful
mountains and sandy
shores. Maude Leonor Menten, a 26-year-old Bavarian chemist, was one
of the first women on the scene, looking for love and the meaning of
life, and their relation to the velocity of chemical reactions.
Assigned to Suite 243C in the research facility at Alhondiga de Granaditas,
she
arrived promptly at the lab at 7:30 each morning, and left at 4:30 in
the afternoon to carouse the local bars and clubs. “I had many,
many men in those days,” said Menten years later. “It
was an exciting life, but one bereft also of moral virtues.”
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Michaelis & Menten |
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Next door, in Suite 243D,
Leonor Michaelis had lived, eaten, and breathed organic chemistry for
six years, having
arrived in Tehaputlan in 1897
just as the gold mines ran dry. Leonor’s lifelong ambition had
been to build a catalytic engine for use in horseless carriages, and
he had come achingly close to completion of his goal when in 1901 he
contracted Bell’s Palsy, leaving him with a right facial droop
which rendered him unable to speak or smile without drooling all over
his finely pressed clothing.
Depressed and alone, he scrapped his plans for the engine
and started work on the development of a synthetic substance that could
be molded into a cup or bowl, with which he hoped to catch some of the
saliva that dribbled daily from the grotesquely loosened right side of
his lips.
By June 1903, aside from
a large puddle of drool, Michaelis had nothing. No engine, no bowl,
and only about 250
million pesos remaining (worth
about $28US today). “It was clear to me,” he would say later, “that
the time had come for me to return to South Africa and go back to doing
what I loved doing: playing guitar.”
Needing some extra rags
or a mop, he knocked on his neighbor’s
door at Alhondiga de Granaditas’ Suite 243C, meeting Menten for
the first time.
Maude Leonora Menten describes
their initial encounter: “When
I saw his face, those sad adorable eyes, one of which was strangely unblinking;
and that endearing half-smile, half-sneer; I knew in that instant that
this was a man who I could be with, if not forever, then at least for
one night.”
That evening, Menten and Michaelis made love for eight hours straight. Thus was born the Michaelis-Menten equation:
V * [S]
v= --------
Km + [S]
where v = reaction rate
[S] = substrate concentration
V = Maximum rate
Km
= Michaelis-Menten constant
The rest, as they say, is history ... and
that’s
the WHOLE story!
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