CONVERSION IN THE PEPTIDES COATING CADMIUM-SULFIDE CRYSTALLITES IN CANDIDA-GLABRATA

Cultures of Candida glabrata treated with CdCl2 form intracellular Cd(II) complexes that evolve with the time of culturing. Initially, glutathione (gammaECG) appears to be the major buffering component. One type of Cd(II)-glutathione complex exists as a cadmium:sulfide (CdS) crystallite coated with glutathione. A time dependent change in the coating of the CdS particles occurs with a decrease in the (gammaECG) content and a corresponding increase in the abundancc of (gammaEC)nG peptides with (gammaEC)2G becoming the predominant peptide. The desGly variant (gammaEC)2 appears in significant concentration only in late cultures. The evolution in isopeptide coating appears to be dependent on the sulfide content of the CdS particles. Cellular conditions that enhance the generation of sulfide ions facilitate the conversion from gammaECG to (gammaEC)2G.