John Westley

Research

John Westley's doctoral research concerned the biosynthesis of histidine in Escherichia coli. Subsequently he became an enzymologist and worked principally on rhodanese (thiosulfate sulfurtransferase, EC 2.8.1.1), starting with a comparison of the enzyme forms isolated from beef liver and kidney and purification of the kidney enzyme.

He continued to study the kinetic behaviour of the liver enzyme, and was probably the first to study memory effects in substituted-enzyme ("ping-pong") mechanisms. Memory effects are also possible in ternary-complex mechanisms, as in the "mnemonical model" used by Ricard and co-workers to explain the deviations from linear kinetics observed in wheat-germ hexokinase. However, the kinetic effects are completely different. The memory effects discussed by Katz and Westley,

Westley was also concerned with more general aspects of enzyme kinetics, such as uncompetitive inhibition in metabolic systems, metabolite channelling, and rapid-equilibrium mechanisms, and regulation.

Enzymic catalysis

In addition to his research publications, Westley is also known for his book Enzymic catalysis, which in its time was an important textbook on the subject.