[Cytology of Candida utilis yeasts under different temperature regimes of continuous cultivation]

Changes in the structure of cells and in the morphology of cytoplasmic membranes (CM) were studied when Candida utilis VKM-1668 was grown under the conditions of continuous cultivation at constant (31 or 37 degrees C) and varying temperatures. The structure of cells was studied using the technique of ultrathin sections, and the morphology of CM was investigated by the technique of freezing-etching. At the optimal temperature of growth, the structure of cells was found to be typical of the yeast while the CM was shown to have a folded surface with narrow slit-like invaginations. When the temperature was elevated, nuclear division and cell separation were inhibited, the dimensions of cells increased, and the slit-like invaginations of CM straightened out. At a varying temperature regime of cultivation, the structure of cells and the morphology of their CM were similar to those observed at the constant optimal temperature of growth.