Induction of secretory acid proteinase in Candida albicans

Banerjee, Anasua ; Ganesan, K. ; Datta, Asis (1991) Induction of secretory acid proteinase in Candida albicans Journal of General Microbiology, 137 (10). pp. 2455-2461. ISSN 0022-1287

[img]
Preview
PDF - Publisher Version
1426Kb

Official URL: http://mic.sgmjournals.org/cgi/content/abstract/13...

Related URL: http://dx.doi.org/10.1099/00221287-137-10-2455

Abstract

Candida albicans and some other pathogenic Candida species, when grown in a medium containing a protein as a sole source of nitrogen, secrete an acid proteinase. Culture supernatants were assayed for proteinase activity, and were also analysed by Western blotting with antibodies raised and affinity-purified against proteinase of C. albicans. Proteinases secreted by C. tropicalis and C. parapsilosis were antigenically related to that of C. albicans, but had different molecular masses. The proteinases secreted by C. lipolytica, C. rugosa and C. lusitaniae were not antigenically related. The kinetics of proteinase secretion by C. albicans were monitored by activity and by Western blotting. With BSA as the nitrogen source, proteinase secretion increased exponentially until about 16 h. Culture supernatants of BSA-grown cultures accumulated proteinase to about a 1000-fold higher level than those of ammonium-sulphate-grown cultures. In vivo labelling experiments showed that proteinase was not detectably accumulated in the cells, but was secreted immediately after synthesis. Immunoprecipitation of in vitro translated poly(A)-containing RNA identified a putative pre-protein of about 54 kDa. As well as BSA, other proteins (haemoglobin, ovalbumin, histone), peptone and tryptone, when used as nitrogen sources, could induce proteinase, but to different levels. When Casamino acids or an amino acid mixture (equivalent to the composition of BSA) was used as nitrogen source, no induction was observed. Ammonium sulphate, or any other ammonium salt, repressed secretion of proteinase.

Item Type:Article
Source:Copyright of this article belongs to Society for General Microbiology.
ID Code:9328
Deposited On:02 Nov 2010 17:59
Last Modified:07 Feb 2011 15:35

Repository Staff Only: item control page