Victor Henri

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Victor Henri around 1922

Victor Henri (born June 6, 1872 in Marseille , † June 21, 1940 in La Rochelle ) was a German-French physical chemist and psychologist of Russian descent. He was best known as a pioneer in enzyme kinetics .

He was extremely productive - he published over 500 scientific articles in various disciplines such as physical chemistry , biochemistry , physiology and psychology , including in German.

Henri received his doctorate twice: in 1897 at the University of Göttingen in the field of psychology and in 1903 in Paris on enzyme kinetics , in 1907 he received a teaching license there. In 1920 he was appointed associate professor for physical chemistry at the University of Zurich . There he did pioneering work in the field of spectroscopy. In 1930 he became professor of physical chemistry at the University of Liège ( Belgium ). His successor at the University of Zurich was Hans von Halban .

In 1902 he published an article in which he was the first to state and derive the basic equation of enzyme kinetics . He wrote this equation as follows

Here, a denotes the initial concentration of the substrate and x the concentration of the product formed. The other symbols stand for constants. In today's notation, the equation could be written like this:

where v denotes the reaction rate, S the substrate concentration, P the product concentration, and K 1 and K 2 denote the dissociation constants of the enzyme-substrate complex and enzyme-product complex, respectively.

It took about ten years for biochemists around the world to realize the full meaning of this equation. Because although Henri’s article and his doctoral thesis on this topic (1903, see above) have been cited many times, Leonor Michaelis and Maud Menten were the first to derive and interpret the equation even more precisely with a groundbreaking article in 1913, thus enabling a wide range of applications. In particular, they correctly and comprehensively interpreted the constants in the equation. The equation is usually used for the special case P = 0 and is usually called Michaelis-Menten kinetics, but sometimes also Henri-Michaelis-Menten kinetics.

It has been suggested that the above Equation (*), which is relevant for the more general case P > 0, should be called Henri kinetics.

S. Nicolas wrote an extensive biographical article on Henri.

Web links

credentials

  1. ^ V. Henri: About the law of the action of the invertin. In: Z. Phys. Chem. 39, 1901, pp. 194-216.
  2. ^ V. Henri: Lois générales de l'action des diastases. Hermann, Paris 1903.
  3. The Physico-Chemical Institute of the University of Zurich was founded 75 years ago. ( Memento from January 2, 2014 in the Internet Archive ) (www.unipublic.uzh.ch)
  4. ^ V. Henri: Théorie générale de l'action de quelques diastases. In: CR Hebd. Séances Acad. Sci. 135, 1902, pp. 916-919.
  5. L. Michaelis, ML Menten: The kinetics of the invertin effect. In: Biochem. Z. 49, 1913, pp. 333-369.
  6. Z. Bajzer, EE Strehler: About and beyond the Henri-Michaelis-Menten rate equation for single-substrate enzyme kinetics. In: Biochem. Biophys. Res. Commun. 417, 2012, pp. 982-985.
  7. U. Deichmann, S. Schuster, J.-P. Mazat, A. Cornish-Bowden: Commemorating the 1913 Michaelis – Menten paper “The Kinetics of Invertin Action”: three perspectives. In: FEBS Journal. 2013, doi: 10.1111 / febs.12598 .
  8. ^ S. Nicolas: Qui était Victor Henri? In: L'Année Psycholog. 94, 1994, pp. 385-402.