Electrophoretic Detection of Cytoplasmic Serine Proteinases (Gelatinases) in Candida albicans

Rodier, M.-H., El Moudni, B., Ghazali, M., Lacroix, C., and Jacquemin, J.-L. 1994. Electrophoretic detection of cytoplasmic serine proteinases (gelatinases) in Candida albicans. Experimental Mycology 18: 267-270. Proteolytic activities of Candida albicans were identified using sodium dodecyl sulfate-polyacrylamide gel electrophoresis with gels containing gelatin as proteinase substrate. Cytoplasmic extracts of five isolates were tested with this method. Two major proteolytic activities of M_r 50,000 and 60,000 were conserved between isolates whereas two other less intense activities of M_r 90,000 and 120,000 were only detected in three isolates. The two bands of proteolysis of M_r, 50,000 and 60,000 were revealed between pH 5.0 and pH 8.0, optimally active at pH 7.0, and their isoelectric point was 4.5. They were not influenced by the presence of 2-mercaptoethanol. Their sensitivity to phenylmethylsulfonyl fluoride and chymostatin allowed them to be characterized as serine proteinases. These two neutral proteinases were not secreted in culture supernatant.