Eleutherio E C, Ribeiro M J, Pereira M D, Maia F M, Panek A D
Departamento de Bioquímica, Universidade Federal do Rio de Janeiro, Brasil.
Biochem Mol Biol Int. 1995 Aug;36(6):1217-23.
Cells of a heat-shock resistant mutant were approximately 1000-times more resistant to lethal heat shock than those of the parental strain. We observed that exponentially growing cells of the mutant synthesized trehalose and showed increased osmotolerance, dehydration tolerance an ethanol tolerance, a fact not observed in wild type strains. The mutant synthesizes constitutively six proteins, among them two proteins of 56 and 63 kDa. Interestingly these molecular weights could correspond to the subunit of trehalose-6-phosphate synthase and to phosphoglucomutase II, respectively. Our results showed that glucose-growing cells of the hsr 1 mutant possessed high levels of activity of these enzymes when compared to the control strain.
热休克抗性突变体的细胞对致死性热休克的抗性比亲本菌株的细胞高约1000倍。我们观察到，突变体中呈指数生长的细胞合成海藻糖，并表现出渗透压耐受性、脱水耐受性和乙醇耐受性增强，而野生型菌株中未观察到这一现象。该突变体组成型合成六种蛋白质，其中两种蛋白质的分子量分别为56 kDa和63 kDa。有趣的是，这些分子量可能分别对应于海藻糖-6-磷酸合酶的亚基和磷酸葡萄糖变位酶II。我们的结果表明，与对照菌株相比，hsr 1突变体中以葡萄糖为生长底物的细胞具有较高水平的这些酶的活性。
