Enzyme inhibitor thermolysin

DePriest SA, Mayer D, Naylor CB, Marshall GR. 3D-QSAR of angiotensinconverting enzyme and thermolysin inhibitors a comparison of CoMFA models based on deduced and experimentally determined active site geometries. J Am Chem Soc 1993 115 5372-84. 

Free Energy Calculations on Enzyme-Inhibitor Complexes Studies of Thermolysin and Rhizopus Pepsin... 

Yokoyama, . H., Chiba, H., and Yoshikawa, M. (1992). Peptide inhibitors for angiotensin-I-converting enzyme from thermolysin digest of dried bonito. Biosci. Biotechnol. Biochem. 56,1541-1545. 

The X-ray structures of enzyme and enzyme-inhibitor complexes permit the anhydride intermediate only in the case of carboxypeptidase, not in the case of thermolysin, since in this enzyme the catalytic Glu-143 is too far away from the substrate carbonyl (Lipscomb, 1983). The proposal that carboxypeptidase works via an anhydride intermediate thus requires the supposition that two very similar enzymes work by different mechanisms. 

De Priest, S. A., et al. 3D-QSAR of Angiotensin-Converting Enzyme and Thermolysin Inhibitors A Comparison of CoMFA Models Based on Deduced and Experimentally Determined Active-Site Geometries,/. Am. Chem. Soe. 

Waller, C.L. and Marshall, G.R. (1993). Three Dimensional Quantitative Structure-Activity Relationship of Angiotesin Converting Enzyme and Thermolysin Inhibitors. 2. A Comparison of CoMFA Models Incorporating Molecular Orbital Fields and Desolvation Free Energies Based on Active Analog and Complementary Receptor Field Alignment Rules. JMeeLChem., 36,2390-2403. 

Figure 9. Thermolysin-inhibitor complex - an example of inhibitors bound to zinc endoproteases with the long spacer consensus. A stereo view of the active site site of thermolysin showing details of enzyme-inhibitor 2 interactions (Brookhaven Databank Code 5TLN). Enzyme side chains involved in inhibitor recognition are shown in magenta. The color code is as given for Fig. 6.

Hangauer et al. (220) used computer modeling techniques to investigate the mechanism of peptide hydrolysis by thermolysin using the crystallographic information on the enzyme, inhibitor, and substrate along with available structure-activity relationships. Using a model substrate, Z-Phe-Phe-Leu-Trp, they modeled the Michaelis complex as well as the tetrahedral intermediate complex. 

Cbz-Gly -L-Leu-L-Leu (7) Ki = 9. nM) (Phe and Gly depict the phosphonic acid analogues of Phe and Gly, respectively) are potent inhibitors for thermolysin. Recent advances in computer chemistry, with structural information of enzymes from X-ray crystal-structure analysis and NMR experiments, made possible the structure-based design of enzyme inhibitors. For instance, macrocyclic thermolysin inhibitors such as (8) were rationally designed. Among all the possible diastereomers synthesized, (S,S)- S) was the most potent (Xi = 4nM) against thermolysin (Scheme 19). ... 

We have also looked at a series of tri- and tetrapeptide phosphonate inhibitors of carboxypeptidase A, with structural variation in the P2 and P3 residues.io Again, we see a good correlation between the Kj and Km/i cat values, supporting the view that the mechanisms of this enzyme and thermolysin are similar. This result is also consistent with the notion that a transition state analog motif that is good for one of these zinc peptidases should work the same way for the otho-. 

Waller CL, Marshall GR (1993) Three-dimensional quantitative structure-activity relationship of angiotesin-converting enzyme and thermolysin inhibitors. II. A comparison of CoMFA models incorporating molecular orbital fields and desolvation free energies based on active-analog and complementary-receptor-field alignment rules. J Med Chem 36(16) 2390-2403... 

In thermolysin (Matthews et al., 1974 Holmes and Matthews, 1982) zinc is bound approximately tetrahedrally to glutamate (monodentate), two histidines, and water. While zinc in the native enzyme is tetracoord-inate, in some inhibitor complexes it is pentacoordinate. The four calcium ions are bound by six to eight oxygen ligands, as shown in Fig. 35, with Ca 0 distances of 2.23-2.71 A. The RNA polymerase from E. coli contains Zn(II) and Mg(II), which may be substituted by Mn(II) (Chuk-nyhVy et al., 1990). 

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