Tosyl elastase

Shotton, D.M., Watson, H.C. Three-dimensional structure of tosyl-elastase. Nature 225 811-816, 1970. 

The remarkable stability of acyl enzymes also indicates that protein conformation is stabilized in several steps in the catalytic process (Bender and Kezdy, 1964 Zerner and Bender 1964 Bernhard and Lau, 1972 Bernhard and Rossi, 1968). Acyl proteases are locked in a conformation which prevents acid and alkaline transitions, (Hess et al., 1970, GhHis, 1971). Stabilization of the acyl enzyme (DIP or tosyl elastase) is indicated by a shift of the transition curve, transition being induced by GuHCl, toward higher concentrations of denaturant (c , varies from 1.6 for elastase to 2.3 for DIP elastase at pH 5.4 and from 2.6 to 3.25 for these two forms respectively at pH 8.0) (Gh61is and Zilber, 1982). 

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