A MODULATORY EFFECT OF YEAST CELL-HUMIC SALT INTERACTION

Na-humate, when added to yeast cultivation media, allows some increase in the cell division rate. This compound was shown to stimulate repro duction activity over all interval of exponential growth of Candida ut ilis cells, and this effect is partially independent of temperature an d pH. The populations of yeast cells growing in the presence of Na-hum ate exhibit a resistance to polyene antibiotic and a higher Cr6+ adsor ption capacity. The ultrathin sections of the cells exposed to Na-huma te show external, electrondense precipitations in the space of the cel l surface as well as some alterations in the cytoplasmic matrix and in terchromatin. The observed changes are attributed to the effect of per manent outer cell wall - humate contact.