Isotope effects on enzyme-catalyzed reactions

Kirsch, J. F. (1977). In Isotope Effects on Enzyme-catalyzed Reactions (ed. W. W. Cleland, M. H. O Leary and D. B. Northrop). University Park Press, Baltimore,... 

Modeling Isotope Effects on Enzyme-Catalyzed Reactions... 

Northrop, D. B. Determining the Absolute Magnitude of Hydrogen Isotope Effects in W.W. Cleland, W. W., O Leary, M., Northrop, D. B. (Eds.) Isotope Effects on Enzyme-Catalyzed Reactions, University Park Press, Baltimore, MD, 1976, pp. 122-152. 

Intrinsic isotope effects on enzyme-catalyzed reactions,... 

Cleland WW, Northrop DB, O Leary MH. Isotope effects on enzyme-catalyzed reactions [Proceedings of the Sixth Annual Harry Steenbock Symposium, held in Madison, Wisconsin, on June 4 and 5,1976]. Baltimore University Park Press 1977. 

Kresge, A. J. (1977). In Isotopes Effects on Enzyme Catalyzed Reactions (W. W. Cleland. 

DB Northrop. The expression of isotope effects on enzyme catalyzed reactions. Annu Rev Biochem 50 103-131, 1981. 

The examples in this section have been chosen to provide an in-depth presentation showing how RSSF currently has been applied to the study of biological systems. These applications include the study of isotope effects on enzyme-catalyzed reactions, the investigation of substrate-metal ion interactions in metalloenzymes, the search for and identification of covalent intermediates in enzyme-catalyzed processes, the analysis of the effects of site-directed mutations on enzyme catalytic mechanism, and the exploitation of natural and artificial chromophores as probes of allosteric processes. 

It is obvious that in order to use Eq. (84) one must know the size of as well as the commitments ( /leq can be readily measured). It was the discovery by Northrop in 1975 that the deuterium and tritium isotope effects on V K could be compared to estimate that opened up the field of isotope effects on enzyme-catalyzed reactions (95) ... 

Isotope effects on enzyme-catalyzed reactions are only rarely fully expressed, since bond-breaking steps are often faster than other steps such as release of reactants. In order to enhance observed isotope effects and obtain information on the degree of rate Umitation of the bond-breaking step, and the location of other rate-limiting steps along the reaction path, the pH can be raised or lowered so that the chemic reaction becomes rate-Umiting (Cook Cleland, 1981 Cook, 1991). Further, the variations of kinetic isotope effects with pH may be used in a profitable way to distinguish between different reaction mechanisms. 

Northrop, D.B. (1977) in Isotope effects on enzyme-catalyzed reactions, pp. 100-130. 

Krankowsky D, Mauersberger K (1996) Science 274 1324 Kresge AJ (1977) In Cleland WW, O Leary MH, Northrop DB (eds) Isotope effects on enzyme-catalyzed reactions. University Park Press, Baltimore, pp 37-63 Krumbiegel P (1970) Isotopieeffekte. Akademie-Verlag, Berlin... 

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