Kim D, Robyt J F
Department of Biochemistry and Biophysics, Iowa State University, Ames 50011.
Enzyme Microb Technol. 1994 Aug;16(8):659-64. doi: 10.1016/0141-0229(94)90086-8.
After chemical mutagenesis using ethyl methane sulfonate, we isolated mutants constitutive for glucansucrases from Leuconostoc mesenteroides NRRL B-512FM, B-1142, and B-1355. Those mutants produced glucansucrases when grown on D-glucose as well as on sucrose. They produced higher glucansucrase activities (3 to 22 times) when grown on D-glucose than the parent strains grown on sucrose. Glucansucrases from mutants B-1355C and B-1142C grown on glucose formed glucans that were highly resistant to Penicillium dextranase hydrolysis. Mutant B-512FMC dextransucrase formed the same kind of dextran as the parent strain; however, it showed higher thermal stability, even when dextran was absent.
使用甲磺酸乙酯进行化学诱变后，我们从肠系膜明串珠菌NRRL B - 512FM、B - 1142和B - 1355中分离出了葡聚糖蔗糖酶组成型突变体。这些突变体在以D - 葡萄糖和蔗糖为碳源生长时均能产生葡聚糖蔗糖酶。当在D - 葡萄糖上生长时，它们产生的葡聚糖蔗糖酶活性比在蔗糖上生长的亲本菌株高（3至22倍）。在葡萄糖上生长的突变体B - 1355C和B - 1142C产生的葡聚糖蔗糖酶形成的葡聚糖对青霉葡聚糖酶水解具有高度抗性。突变体B - 512FMC葡聚糖蔗糖酶形成的葡聚糖与亲本菌株相同；然而，即使不存在葡聚糖，它也表现出更高的热稳定性。
