Rapid purification of secretory acid proteinase from Candida albicans and its characterization.
Secretory acid proteinase from C. albicans was purified from culture supernatant to apparent homogeneity by ion-exchange chromatography. Two isozymes of the proteinase were resolved using a novel chromatofocusing method. The enzyme, which appears to be a glycoprotein, consists of a single polypeptide chain with glutamine at the N-terminus. Its molecular weight is about 45,000 and isoelectric point is pH 4.6. At pH 5, the proteinase is stable at 45 degrees C for at least 15 min. It has a broad substrate specificity. With BSA as a substrate, Km was determined to be 1.6 x 10(-4) M. The enzyme is inhibited by pepstatin and thus is a carboxyl proteinase. It undergoes autocatalytic digestion at or below pH 5.0. The kinetics of induction of proteinase by various proteins are also reported.
Banerjee
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A
Molecular Biology Laboratory, School of Life Sciences, Jawaharlal Nehru University, New Delhi.
Ganesan
K
K
Datta
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D000596:Amino Acids / Q000032:analysis; D002176:Candida albicans / Q000201:enzymology; D010450:Endopeptidases / Q000302:isolation & purification* / Q000378:metabolism; D007526:Isoelectric Point; D007527:Isoenzymes / Q000302:isolation & purification; D007700:Kinetics; D008970:Molecular Weight
D000596:Amino Acids; D007527:Isoenzymes; D010450:Endopeptidases