title: Properties of a cytoplasmic proteolytic enzyme from Escherichia coli.
abstract: A cytoplasmic protease was partially purified from Escherichia coli; its sedimentation coefficient was found to be 5.3 S. This enzyme (which we call protease A) is not a serine protease and cysteine is not required for its activity; it is only active in the presence of divalent ions which are strongly bound to it. After inactivation of protease A by incubation at 50 degrees C in the presence of 1 mM EDTA, the enzyme is reactived by Mg2+, Mn2+ or Ca2+. We have tried most of the usual esters as substrates and found that none was hydrolyzed by the enzyme which induces a highly restricted specificity.
mesh_terms: D002118:Calcium / Q000494:pharmacology; D002364:Caseins; D002848:Chromatography, DEAE-Cellulose; D002850:Chromatography, Gel; D003545:Cysteine / Q000494:pharmacology; D003593:Cytoplasm / Q000201:enzymology; D004355:Drug Stability; D004492:Edetic Acid / Q000494:pharmacology; D004789:Enzyme Activation / Q000187:drug effects; D004926:Escherichia coli / Q000201:enzymology*; D006358:Hot Temperature; D007700:Kinetics; D008274:Magnesium / Q000494:pharmacology; D008345:Manganese / Q000494:pharmacology; D008970:Molecular Weight; D010447:Peptide Hydrolases / Q000302:isolation & purification / Q000378:metabolism*; D013997:Time Factors
chemical_list: D002364:Caseins; D008345:Manganese; D004492:Edetic Acid; D010447:Peptide Hydrolases; D008274:Magnesium; D003545:Cysteine; D002118:Calcium