Subtilisin and alpha-chymotrypsin vigorously act as catalysts in a variety of dry organic solvents. Enzymatic transesterifications in organic solvents follow Michaelis-Menten kinetics, and the values of V/Km roughly correlate with solvent's hydrophobicity. The amount of water required by chymotrypsin and subtilisin for catalysis in organic solvents is much less than needed to form a monolayer o...

The mustard trypsin inhibitor, MTI-2, is a potent inhibitor of trypsin with no activity towards chymotrypsin. MTI-2 is toxic for lepidopteran insects, but has low activity against aphids. In an attempt to improve the activity of the inhibitor towards aphids, a library of inhibitor variants was constructed and cloned into the pRlac3 phagemid vector. The library of 9.3 x 107 independent colonies ...

Plants produce a variety of proteinase inhibitors (PIs) that have a major function in defense against insect herbivores. In turn, insects have developed strategies to minimize the effect of dietary PIs on digestion. We have discovered that Helicoverpa larvae that survive consumption of a multidomain serine PI from Nicotiana alata (NaPI) contain high levels of a chymotrypsin that is not inhibite...

* Trabalho elaborado com auxílio financeiro da FAPESP (Processo no 98/11620-8) e PADCT/CNPq (Processo no 620164/97-2). ** Departamento de Alimentos e Nutrição Faculdade de Ciências Farmacêuticas UNESP 14801-902 Araraquara SP Brasil. *** Departamento de Engenharia Química UFSCar 13565-905 São Carlos SP Brasil. ABSTRACT: This work presents a method for adding value to cheese whey residues by whey...

Exocrine pancreatic proteolytic activity, determined by serial measurement of faecal chymotrypsin concentration, was investigated in 21 preterm infants (23-32 weeks' gestation) during the first 28 days of life. The overall chymotrypsin concentration range was similar to that already described in term infants showing that pancreatic chymotrypsin secretion is equally well developed at birth in th...

Trypsin and chymotrypsin are both serine proteases with high sequence and structural similarities, but with different substrate specificity. Previous experiments have demonstrated the critical role of the two loops outside the binding pocket in controlling the specificity of the two enzymes. To understand the mechanism of such a control of specificity by distant loops, we have used the Gaussian...

Previous papers (1, 2) have reported the acylation of chymotrypsin with several nitrophenyl acetates. It was of obvious interest to test the behavior of nitrophenyl esters of other acids in the same connection. It now appears that chymotrypsin may be acylated by a number of acids differing considerably from acetic acid in structure. Beneoyl and salicyl chymotrypsins were prepared and found to r...