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PROTEOLYTIC ENZYMES AND BIOLOGICAL INHIBITORS
Author(s) -
Fossum Kåre
Publication year - 1970
Publication title -
acta pathologica microbiologica scandinavica section b microbiology and immunology
Language(s) - English
Resource type - Journals
SCImago Journal Rank - 0.909
H-Index - 88
eISSN - 1600-0463
pISSN - 0365-5563
DOI - 10.1111/j.1699-0463.1970.tb04366.x
Subject(s) - proteus vulgaris , serratia marcescens , trypsin , bacteria , biochemistry , proteolytic enzymes , chymotrypsin , enzyme , microbiology and biotechnology , chemistry , pepsin , papain , serratia , escherichia coli , gram negative bacteria , casein , proteus , biology , pseudomonas , genetics , gene
Extracts from disintegrated cells of some Gram‐negative bacteria, including Proteus mira‐bilis, Proteus vulgaris, Escherichia coli , a Klebsiella species, Serratia marcescens , and Pseudomonas aeruginosa were shown to inhibit the activity of trypsin, α‐chymotrypsin, and the extracellular proteinases of certain microorganisms, as tested by the casein precipitating inhibition test (CPI‐test). The crude extracts of the various proteolytic Gram‐negative bacteria did, in all cases, inhibit the extracellular proteinase produced by the homologous species. Ficin and papain were not inhibited by any of the bacterial inhibitors tested. Disintegrated cells of Gram‐positive microorganisms showed no inhibitory activity. By electrophoresis of the inhibitor‐containing material, combined with the CPI‐test (electro‐phoretic CPI‐test), two electrophoretically distinguishable inhibitors were demonstrated from the Proteus bacteria, one which inhibited only trypsin and α‐chymotrypsin, and another which, in addition to affecting these two enzymes to some extent, also inhibited microbial proteinases. Only one inhibitor was demonstrated by this method from each of the other Gram‐negative bacteria. The inhibitors, which are assumed to be proteins, were non‐dialysable, they were precipitable by ammonium sulphate, but not by streptomycin sulphate. They were inactivated by the action of pepsin, and were fairly heat stable in the crude preparation.