ENZYME KINETICS 



ROBERT A. ALBERTY, Chemistry Department, University of Wisconsin, 



Madison, Wisconsin 



In living organisms enzymes determine which of the multi- 

 tudinous thermodynamically possible reactions occur and at 

 what rates these reactions can proceed. Most of these reactions 

 cannot be duplicated in the laboratory without the use of 

 enzymes, especially in neutral solution and at body tempera- 

 tures. Thus we are presented with the challenge of probing the 

 secrets of these catalytic mechanisms. Quantitative kinetic 

 studies do not have a monopoly in this field of inquiry, but 

 they play an important role which is discussed in this article. 



The role of quantitative studies of enzyme kinetics may 

 perhaps be clarified by consideration of the following analogy. 

 A multicomponent enzyme system may be compared to a watch 

 and the process of discovering the mechanism to the maneuvers 

 of a boy who takes the watch apart. If our young experimental- 

 ist is suflSciently careful and observant, he may be able to put 

 it back together again and find that it still works. However, the 

 significant thing about the watch, which is its ability to keep 

 time, does not lie simply in the number of gears or in the fact 

 that it has a spring, but in the quantitative factors that the boy 

 does not measure. The factors which make it possible for the 



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