摘要
通过向枯草芽孢杆菌Ki-2-132染色体和/或细胞质导入来自枯草杆菌168菌株的 degU32 (Hy)和 degR 基因,以及来自芽孢杆菌解淀粉菌株(Bacillus amyloliquefaciens)的 degQa 基因,对上述基因对枯草芽孢杆菌 Ki-2-132 细胞的生长、孢子发生、蛋白酶发酵的影响进行了研究。尽管上述多效调控基因来自不同的芽孢杆菌种和菌株, 它们在枯草芽孢杆菌Ki-2-132 中依然表现多效性。枯草杆菌 Ki-2-132 degU32 (Hy)表现出增高了的蛋白酶产量;当和质粒或染色体上的 degQa 基因协作,可以进一步依赖葡萄糖的水平和degQa的基因剂量影响细胞生长,增加蛋白酶产量,以及影响孢子的形成。与此不同,degR在degU32 (Hy) 突变体中并不显著影响其蛋白酶的产量,这一发现支持DegR蛋白通常稳定磷酸化的 DegU,而其在degU32 (Hy) 菌株中不再进一步放大该突变体内已被磷酸化的 DegU的调控作用。
Effects of degU32 （Hy）, degR genes from Bacillus subtilis 168 and degQa gene from Bacillus amyloliquefaciens on Bacillus subtilis Ki-2-132 cell growth, sporulation and protease fermentation were investigated by introducing these genes into B. subtilis Ki-2-132 chromosome and/or cytoplasm. Although the genes come from different species and strains, they showed pleiotropic effects in B. subtilis Ki-2-132. B. subtilis Ki-2-132degU32 （Hy） showed increased protease production, and when cooperating with degQa either in plasmid or in chromosome, further altered cell growth, increased protease production and affected the spore formation in a glucose and dosage dependent manner. By contrast, degR did not significantly affect the protease productivity in degU32 （Hy） mutant, consisting with that DegR was used to stabilise DegU-phosphate, which in degU32 （Hy） strain no longer further amplify the DegU-phosphate effect.
基金
This work was supported by Chinese National Programs for High Technology Research and Development (863 Program).
