Synthesis of seleno-amino-acids in cell free extracts of Candida albicans.

Abstract

SELENIUM, long considered an element toxic to the majority of living organisms, may be of physiological importance in various animals as an indispensable part of the diet1–5. It may replace the sulphur atom in sulphur amino-acids6–14 in the proteins of plants, animals and micro-organisms15–18, and could stimulate cell division in a filamentous mutant of Candida albicans19. This stimulation has been related to the replacement of sulphydryl groups in the composition of the cell wall with —SeH groups, the greater stability of which can overcome in the filamentous mutant the deficiency in proteiin-disulphuro-reductase20, an enzyme indispensable to plastification of the cell wall21.