Parks L W, Casey W M
Department of Microbiology, North Carolina State University, Raleigh 27695-7615, USA.
Annu Rev Microbiol. 1995;49:95-116. doi: 10.1146/annurev.mi.49.100195.000523.
Fungi are among the most primitive organisms that synthesize sterols. The fungal sterol, ergosterol, is similar to animal sterol, cholesterol, but with significant structural differences. The genetics and biochemistry for most of the steps in sterol biosynthesis have been studied in the yeast, Saccharomyces cerevisiae. Yet, little is known of the precise physiological roles that sterols play in the cell. Work with strains that are auxotrophic for ergosterol has led to the prediction of at least four growth-dependent functions for sterols. Most of the antifungal compounds in medical and agricultural use affect some aspect of sterol synthesis or function. Extensive studies on the modes of action of those substances and research on the effects of altering sterol metabolism by sterol mutants are providing new insights into sterol functions in the cells. In addition, questioning why fungi require ergosterol rather than the simpler cholesterol provides heuristic impetus for further experimentation.
真菌是合成甾醇的最原始生物之一。真菌甾醇麦角甾醇与动物甾醇胆固醇相似，但结构上有显著差异。甾醇生物合成中大多数步骤的遗传学和生物化学已在酿酒酵母中进行了研究。然而，对于甾醇在细胞中所起的确切生理作用却知之甚少。对麦角甾醇营养缺陷型菌株的研究已经预测出甾醇至少有四种依赖生长的功能。医学和农业上使用的大多数抗真菌化合物都会影响甾醇合成或功能的某些方面。对这些物质作用方式的广泛研究以及对甾醇突变体改变甾醇代谢影响的研究，正在为甾醇在细胞中的功能提供新的见解。此外，探究真菌为何需要麦角甾醇而非更简单的胆固醇，为进一步实验提供了启发式的动力。
