Cloning and characterization of the plasma membrane H(+)-ATPase from Candida albicans

Abstract

The Candida albicans PMAI gene was isolated from a genomic library by using a hybridization probe obtained from the PMAI gene of Saccharomyces cerevisiae. The fungal plasma membrane H+-ATPase is an electrogenic proton pump with a Mr of -100 kDa that regulates intracellular pH, maintains ion balance, and generates the electrochemical proton gradient necessary for nutrient uptake (39, 44). The H+-ATPase is encoded by the PMAJ gene (47) and is a member of the extended family of the P-type ATPases that mediate cation transport. The PMA genes from several fungal species are highly conserved at both the DNA and amino acid levels, despite the long evolutionary history of the group (13,15,46,47). The PMAI gene of Saccharomyces cerevisiae is essential (47), and molecular genetic manipulation of PMAI expression (37,53) demonstrated that the enzyme regulates the rate of cell growth.

Altered plasma membrane H+‐ATPase from the Dio‐9‐resistant pmal‐2 mutant of Schizosaccharomyces pombe

“…Glucose induces only minor changes in the vanadate sensitivity and maximal velocity of the enzyme. The closely related H +-ATPase from C. albicans wa5 recently shown to respond weakly to glucose metabolism [8]. Therefore, it seem likely that the effects of glucose on the catalytic properties of the plasma membrane H + -ATPase are conserved to different extents among fungi.…”

“…1) in the pmal and pma2 H+-ATPascs of S. pomhe [7,211 and S. cerevisiae [4, 221, in the pmal H + -ATPase of N . crassa [S, 61 and C. albicans [8] and is also found in monocot [23] and dicot [24-261 plant H+-ATPases. No nucleotide change was detected in the S .…”

Structure, function and regulation of plasma membrane H+‐ATPase

“…Other recent findings which deserve attention are briefly listed. The cloning of Candida albi-CMS ATPase [5] may facilitate the rational design of badly needed antifungal drugs. In Saccharomyces cerevisiae, the analysis of intragenic revertants has provided evidence for coupling between transmembrane and cytoplasmic domains [6].…”

Functional characterization of a H+/nucleoside co‐transporter (CaCNT) from Candida albicans, a fungal member of the concentrative nucleoside transporter (CNT) family of membrane proteins

“…Alkaline pH, for instance, promotes germ tube formation, whereas acidic pH encourages yeast growth (Buchan and Gow, 1991). In yeast, protons are likely to be the preferred coupling ion for nutrient transport, since a H + electrochemical gradient is maintained by plasma membrane H + /ATPase (Monk et al, 1991). In C. albicans, proton-pump inhibitors have been shown to inhibit germ tube formation, favouring instead a period of extended yeast growth (Biswas et al, 2001), presumably by reducing the alkalization of intracellular pH that normally precedes the yeast-hyphal transition (Kaur et al, 1988;Kaur and Mishra, 1991a).…”