The Michaelis-Menten Equation

August 10, 2005

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.”

Michaelis & Menten

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!

Remember: Quality Without The Q Is Just Uality!