Ivanov V N, Pindrus A A
Institute of Microbiology and Virology, Academy of Sciences of Ukraine, Kiev.
Mikrobiol Zh (1978). 1993 Jan-Feb;55(1):28-37.
The utilization of the intracellular and extracellular sources of carbon and energy during the mitotic cycle of yeasts Saccharomyces cerevisiae, Kluyveromyces marxianus, Candida boidinii, Candida tropicalis has been studied. Increase in the consumption rate of carbon and energy sources and in the exogenous respiration rate at G1- and G2-phases of the mitotic cycle is shown. The rate of the endogenous respiration of the cells at these phases decreased. The hypothesis has been proposed that during the mitotic cycle of the yeast cell the regular alternation of exotrophy (the utilization of the extracellular carbon and energy sources by a cell) and endotrophy (the process of the utilization of the intracellular carbon and energy sources by a cell) occurs. It is possible to reveal the exotrophic cells by the cytological method which is based on the calculation of dead cells after incubation of the yeast suspension in amyl alcohol solution. This method has revealed that exotrophic and endotrophic processes do not predominate one over another but alternate at the mitotic cycle. Exotrophy and endotrophy are phase-specific processes. The G1- and G2-phases are exotrophic processes, phases S and M are endotrophic ones.
对酿酒酵母、马克斯克鲁维酵母、博伊丁假丝酵母、热带假丝酵母在有丝分裂周期中细胞内和细胞外碳源与能源的利用情况进行了研究。结果表明，在有丝分裂周期的G1期和G2期，碳源和能源的消耗速率以及外源呼吸速率均有所增加。而在这些阶段，细胞的内源呼吸速率下降。有人提出假说，即在酵母细胞的有丝分裂周期中，存在外营养（细胞利用细胞外碳源和能源）和内营养（细胞利用细胞内碳源和能源的过程）的规律性交替。通过基于将酵母悬浮液在戊醇溶液中孵育后计算死细胞数量的细胞学方法，可以揭示外营养细胞。该方法表明，外营养和内营养过程并非一方占主导，而是在有丝分裂周期中交替出现。外营养和内营养是阶段特异性过程。G1期和G2期是外营养过程，S期和M期是内营养过程。
