枯草芽孢杆菌
突变体
减压
渗透性休克
生物
调节器
渗透浓度
严格的回应
野生型
分解代谢抑制
操纵子
渗透压
拉伤
突变
遗传学
微生物学
杆菌科
生物化学
基因
细菌
基因表达
心理压抑
解剖
作者
Sandra M. Ruzal,Carmen Sánchez-Rivas
摘要
Bacillus subtilis cultures submitted to an osmotic upshock (1.5 M NaCl) lysed unless stationary phase had been reached. Several physiological variations were observed, such as delayed growth (adaptation), a filamentous bacterial appearance, RecA-dependent osmoresistance (SOS), and cross-induction by a previous stress (heat shock). Osmoresistance and sporulation seem to share pathways of regulation such as inhibition in the presence of glucose and glutamine and derepression in a catabolite-resistant mutant such as degUh. However, spores were not obtained on hypertonic media. Mutants of later sporulation stages (spoII, spoIII) presented a response similar to that of the wild-type parent, indicating that both processes probably shared early controls. Null mutations in any of the known key modulators of sporulation (spoOA or degU) resulted in similar levels of osmosensitivity. Sensor mutations in kinA and degS also led to strains with altered responses, the kinA mutant being even more osmosensitive than the degS mutant. Several spoOA mutant phenotypes are due to this gene's control of abrB, a regulator of stationary-phase events, and an abrB mutation relieved the osmosensitivity of the spoOA-containing mutant but had no effect on a wild-type strain.
科研通智能强力驱动
Strongly Powered by AbleSci AI