Isolation of a Candida utilis Variant by Using a Nitrogen-limited Continuous Culture

DÍAZ RICCI, JUAN C.; TELL, FRANCISCO

CURRENT MICROBIOLOGY

SPRINGER

Lugar: Berlin; Año: 1988 vol. 17 p. 43 - 48

0343-8651

During continuous culture of Candida utilis the appearance ofa morphologic variant yeast was detected. The new microorganismdeveloped systematically whenever it was changed from normal to stressedpropagation conditions. A simple system was used for the isolation of the yeastvariant, which was defective in cellular division and showed improved kineticparameters and oxygen uptake rate. An asynchronic nitrogen-limited continuousculture of Candida utilis allowed us to enrich the population inthe chemostat with the modified yeast and isolate it in a defined medium.Assimilation and fermentation tests indicated it to be a variant of Candidautilis that showed stable morphologic and physiologic differences withthe parental yeast. Candida utilis growing in this nitrogen-limitedcontinuous culture also showed a high mutation rate.