Temperature-sensitive glucosamine auxotroph of Saccharomyces cerevisiae.
Temperature-sensitive glucosamine auxotroph of Saccharomyces cerevisiae.
复制标题
酿酒酵母温度敏感的葡萄糖胺营养缺陷型。
DOI：
10.1128/mcb.1.1.9-12.1981
复制
发表时间：
1981
影响因子：
5.3
通讯作者：
Ballou,CE
中科院分区：
文献类型：
--
作者：
Ballou,L;Grove,JR;Roon,RJ;Wiggs,J;Ballou,CE
温度敏感回复突变体是从本实验室先前获得的酵母D-葡糖胺营养缺陷型中分离出来的（W. L. Whelan和C. E. 124：1545-1557，1975）。营养缺陷型缺乏酶2-氨基-2-脱氧-D-葡萄糖-6-磷酸酮醇异构酶（EC 5.3.1.19），并且回复突变体似乎在酶活性的形成中是温度敏感的。它们在允许条件下产生的酶以与野生型酶相当的速率衰减活性，并且具有相似的动力学性质。纯合二倍体突变体在非允许温度下无法形成孢子。进行了温度变化实验，以确定葡萄糖胺缺乏对甘露糖蛋白分泌的影响，这反映在外部天冬酰胺酶的形成上。尽管结果因残余酮醇异构酶活性的缓慢衰减而变得复杂，但它们确实表明，当D-葡糖胺的内部库耗尽时，甘露糖蛋白的合成或分泌发生了改变。
Temperature-sensitive revertants were isolated fromSaccharomyces cerevisiaeD-glucosamine auxotrophs previously obtained in this laboratory (W. L. Whelan and C. E. Ballou, J. Bacteriol.124:1545–1557, 1975). The auxotrophs lack the enzyme 2-amino-2-deoxy-D-glucose-6-phosphate ketol-isomerase (EC 5.3.1.19), and the revertants appear to be temperature sensitive in the formation of enzyme activity. The enzyme they produce under permissive conditions decays in activity at a rate comparable to that of the wild-type enzyme, and it has similar kinetic properties. The homozygous diploid mutant fails to sporulate at the nonpermissive temperature. Temperature shift experiments were carried out in an effort to determine what effect glucosamine deficiency had on mannoprotein secretion as reflected in the formation of external asparaginase. Although the results were complicated by the slow decay of the residual ketol-isomerase activity, they did show that mannoprotein synthesis or secretion was altered when the internal pool of D-glucosamine was depleted.