COMPOSITION AND MORPHOLOGY OF CANDIDA-UTILIS GROWN IN CONTINUOUS CULTURE WITH DECREASING CONCENTRATIONS OF PHOSPHATE

Candida utilis was grown in continuous culture with decreasing concentrations of phosphate. At a constant dilution rate three successive growth patterns were observed: carbon-limited growth, carbon and phosphate dual-limited growth, and phosphate-limited growth. Phosphate deficiency as well as phosphate limitation produced significant modifications in cell composition and morphology, including cell size. At the lowest phosphate concentration (6 mg/P/I), the cell size was the largest and the relative contents of phosphorus and RNA in the cells was very low, with 96% of the total phosphorus being located in the RNA fraction.