Cheung H Y, Vitković L
Laboratory of Molecular Biology, National Institute of Neurological and Communicative Disorders and Stroke, Bethesda, MD 20892.
Can J Microbiol. 1988 May;34(5):583-7. doi: 10.1139/m88-097.
RodA and rodB mutations cause rod-shaped Bacillus subtilis cells to become coccus-shaped when the growth temperature is increased from 30 to 45 degrees C. At 30 degrees C four rod strains sporulated as well as the genetically closely related rod+ strains. In contrast, at 45 degrees C the sporulation frequencies of rod strains decreased approximately 10(2)- to 10(4)-fold, while those of rod+ strains remained either unchanged or decreased only slightly. Temperature shift experiments and ultrastructural data indicated that coccus-shaped cells were unable to form prespore septa and were, therefore, inhibited at stage 0 of sporulation.
当生长温度从30℃升高到45℃时,RodA和rodB突变会导致杆状枯草芽孢杆菌细胞变成球菌状。在30℃时,四种杆状菌株的产孢情况与遗传关系密切的杆状野生型菌株相同。相比之下,在45℃时,杆状菌株的产孢频率下降了约10²至10⁴倍,而杆状野生型菌株的产孢频率要么保持不变,要么仅略有下降。温度转换实验和超微结构数据表明,球菌状细胞无法形成前芽孢隔膜,因此在产孢的0阶段受到抑制。