Balasundaram D, Tabor C W, Tabor H
Laboratory of Biochemical Pharmacology, National Institute of Diabetes and Digestive and Kidney Diseases, National Institutes of Health, Bethesda, MD 20892.
Proc Natl Acad Sci U S A. 1991 Jul 1;88(13):5872-6. doi: 10.1073/pnas.88.13.5872.
A null mutation in the SPE2 gene of Saccharomyces cerevisiae, encoding S-adenosylmethionine decarboxylase, results in cells with no detectable S-adenosylmethionine decarboxylase, spermidine, and spermine. This mutant has an absolute requirement for spermidine or spermine for growth; this requirement is not satisfied by putrescine. Polyamine-depleted cells show a number of microscopic abnormalities that are similar to those reported for several cell division cycle (cdc) and actin mutants. These include a striking increase in cell size, a marked decrease in budding, accumulation of vesicle-like bodies, absence of specific localization of chitin-like material, and abnormal distribution of actin-like material. The absolute requirement for polyamines for growth and the microscopic abnormalities are not seen if the cultures are grown under anaerobic conditions.
酿酒酵母中编码S-腺苷甲硫氨酸脱羧酶的SPE2基因发生无效突变，导致细胞中无法检测到S-腺苷甲硫氨酸脱羧酶、亚精胺和精胺。该突变体对亚精胺或精胺的生长有绝对需求；腐胺无法满足这一需求。多胺耗尽的细胞表现出许多微观异常，这些异常与报道的几种细胞分裂周期（cdc）和肌动蛋白突变体相似。这些异常包括细胞大小显著增加、出芽显著减少、囊泡样物体积累、几丁质样物质缺乏特异性定位以及肌动蛋白样物质分布异常。如果在厌氧条件下培养，细胞对多胺的绝对生长需求和微观异常现象则不会出现。
