Bowen J E, Gauch H G
Department of Botany, University of Maryland, College Park, Maryland.
Plant Physiol. 1966 Feb;41(2):319-24. doi: 10.1104/pp.41.2.319.
AN INVESTIGATION WAS UNDERTAKEN TO DETERMINE WHETHER ANY OF THE FOLLOWING FUNGI HAD A REQUIREMENT FOR BORON (B): Saccharomyces cerevisiae, Aspergillus niger, Neurospora crassa, and Penicillium chrysogenum. Boron was unessential, and hence a study was made of the concentrations of B that reduced the growth of S. cerevisiae and P. chrysogenum and the mode of action of the B toxicity. Fifty and 4000 mg B/liter, respectively, significantly (5% level) reduced the growth of the latter 2 species.In both, glycolysis appeared to be inhibited by toxic levels of B, since the cells accumulated fructose-1,6-diP and ADP, but were low in glyceraldehyde-3-P and ATP. With S. cerevisiae growing on glucose, 150 mg B/liter significantly reduced CO(2) evolution. When glyceraldehyde was substituted for glucose, CO(2) evolution and O(2) consumption were unaffected by this level of B.Aldolase was suspected of being inhibited by high B, and this was confirmed using a crude aldolase extract from S. cerevisiae and purified rabbit muscle aldolase. The inhibition of aldolase by B was uncompetitive.With aldolase activity being reduced by toxic levels of B, the fungi were apparently unable to utilize carbohydrates at a rate sufficient to maintain the metabolic processes involved in growth and reproduction.
开展了一项调查，以确定以下真菌是否需要硼（B）：酿酒酵母、黑曲霉、粗糙脉孢菌和产黄青霉。硼并非必需元素，因此对降低酿酒酵母和产黄青霉生长的硼浓度及其毒性作用方式进行了研究。每升50毫克和4000毫克的硼分别显著（5%水平）抑制了后两种真菌的生长。在这两种真菌中，糖酵解似乎都受到硼毒性水平的抑制，因为细胞积累了果糖-1,6-二磷酸和二磷酸腺苷，但甘油醛-3-磷酸和三磷酸腺苷含量较低。当酿酒酵母在葡萄糖上生长时，每升150毫克的硼显著降低了二氧化碳的释放量。当用甘油醛替代葡萄糖时，这个硼水平对二氧化碳释放量和氧气消耗量没有影响。怀疑醛缩酶受到高硼的抑制，使用酿酒酵母的粗醛缩酶提取物和纯化的兔肌肉醛缩酶证实了这一点。硼对醛缩酶的抑制是非竞争性的。由于硼的毒性水平降低了醛缩酶的活性，真菌显然无法以足以维持生长和繁殖所涉及的代谢过程的速率利用碳水化合物。
