Mechanisms of enzyme catalysis

P. J. Tonge, R. P. Carey, Forces, Bond Lengths, and Reactivity-Fundamental Insight into the Mechanism of Enzyme Catalysis , Biochemistry 1992, 31, 9122-9125. 

A detailed understanding of the mechanism of enzyme catalysis and of the reasons for enzyme catalytic efficiency requires knowledge of the... 

The methods for measuring the value of these constants are described in Appendix 3.4. They are important to biochemists and enzymologists interested in kinetics and mechanisms of enzyme catalysis. It is not, however, always appreciated that they are also important in physiology and in the medical sciences. 

III. Catalysis of Reactions by Enzymes at Physiologic Temperature rV. Mechanisms of Enzyme Catalysis 27... 

The mechanism of enzyme catalysis drawn, using (a)random ternary complex theory, (b)ordered ternary complex mechanism and (c) ping-pong bi-bi mechanism ... 

M. Hasslacher, C. Kratky, H. Griengl, H. Schwab, S. D. Kohlwein, Hydroxynitrile lyase from Hevea hrasiliensis, molecular characterization and mechanism of enzyme catalysis. Proteins 1997, 27, 438-449. 

The idea that statistical fluctuations play a role in the mechanism of enzyme catalysis is intriguing. However, as far as I know, no experimental evidence exists to support such a hypothesis. 

The concept of the enzyme-substrate complex is the foundation stone of enzyme kinetics and our understanding of the mechanism of enzyme catalysis. In honor of its introducer, this noncovalently bound complex is often termed the Michaelis complex. 

Although the use of pre-steady state kinetics is undoubtedly superior as a means of analyzing the chemical mechanisms of enzyme catalysis (Chapters 4 and 7), steady state kinetics is more important for the understanding of metabolism, since it measures the catalytic activity of an enzyme in the steady state conditions in the cell. 

Chapter 8, How Enzymes Work, starts with a description of the basic chemical mechanisms that are exploited by enzymes. The latter half of this chapter presents a detailed description of how three enzymes—chymotrypsin, RNase, and triose phosphate isomerase—exploit these basic mechanisms of enzyme catalysis. 

The solubilization phenomenon, which refers to the dissolution of normally insoluble or only slightly soluble compounds in water caused by the addition of surfactants, is one of the most striking effects encountered for surfactant systems. Solubilization is of considerable physico-chemical interst, such as in discussion of the structure and dynamics of micelles and of the mechanism of enzyme catalysis, and has numerous practical applications, such as in detergency, in pharmaceutical preparations and in micellar catalysis. In biology, solubilization phenomena are most significant, e.g., cholesterol solubilization in phospholipid bilayers and fat solubilization in fat digestion and transport. 

A reactant in an enzyme catalysed reaction is known as substrate. According to the mechanism of enzyme catalysis, the enzyme combines with the substrate to form a complex, as suggested by Henri (1903). He also suggested that this complex remains in equilibrium with the enzyme and the substrate. Later on in 1925, Briggs and Haldane showed that a steady state treatment could be easily applied to the kinetics of enzymes. Some photochemical reactions and some enzymic reactions are reactions of the zero order. 

The mechanism of enzyme catalysis mediated by MPO is similar to other heme-containing peroxidases MPO reacts with hydrogen peroxide to yield several spectroscopically distinct forms of the enzyme. MPO-compound I is a short-lived... 

Free Energy Change and TS Theory. We will now express the mechanism of enzyme catalysis "Equation 1" in terms of the change in the free energy as follows ... 

While there is no doubt that bound NAD enhances acylation (117) as well as deacylation (70), it is difficult to reconcile the above-mentioned cooperative effects with the observation (165) that NAD occupation of one site in the rabbit tetramer did not affect the catalytic activity of the other three sites toward aldehyde substrates. Evidence against a slow isomerization of the T->R variety, which might be expected to affect thiol reactivity in other subunits, is the fact that the sturgeon apoenzyme is almost instantaneously active in acylation, following the addition of NAD (116). The nature of the NAD enhancement of acylation and deacylation is of considerable interest since it has a bearing on the mechanism of enzyme catalysis in general, and also because it explains the NAD requirement of a number of the minor activities of GPD (see Section... 

It would be better if the peer-review system did not make mistakes, but I don t think we should try to change it much. Unusual results are often difficult to accept. The two most original things I ever pubhshed, I had a hard time to get published at first. Besides the binding change mechanism, the other dealt with how isotope exchange measurements could be used to probe the mechanism of enzyme catalysis. It was finally published in the Archives of Biochemistry and Biophysics, where I had originally submitted... 

The exact mechanism of enzyme catalysis as well as the structural and energetic aspects of substrate and inhibitor binding have been studied with the aid of molecular modeling, based on the complex of Neu5Ac with influenza virus A/Tokyo/3/67 neuraminidase (Scheme 16.4) [74c]. 

Effects of Temperature and pH on Enzyme-Catalyzed Reactions Detailed Mechanisms of Enzyme Catalysis... 

Tonge, P. j., Carey, P. R. (1992) Forces, bond lengths, and reactivity fundamental insight into the mechanism of enzyme catalysis. Biochemistry 31, 9122-9125. 

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