Yamanaka K, Araki J, Takano M, Sekiguchi J
Department of Applied Biology, Faculty of Textile Science and Technology, Shinshu University, Nagano, Japan.
FEMS Microbiol Lett. 1997 May 15;150(2):269-75. doi: 10.1111/j.1574-6968.1997.tb10380.x.
Bacillus subtilis vegetative cells undergo autolysis when exposed to cold shock treatment. A mutant (CA1) resistant to cold shock was isolated, and its DNA was used for the transformation of B. subtilis 168AR. The transformant (TR1) and CA1 had almost completely lost major vegetative autolysins (Cw1B and Cw1G) and motility, and showed a filamentous cell morphology during the exponential phase. Expression of the sigD-lacZ fusion was reduced in TR1. But the introduction of a SigD overproducing plasmid, pHYSigD, into TR1 led to a considerable increase in the amount of autolysin, a normal cell morphology (short rod), and the cold shock-sensitive phenotype. However, motility was not restored in the transformant. The roles of pleiotropic genes in cold shock-induced autolysis are discussed.
枯草芽孢杆菌的营养细胞在受到冷休克处理时会发生自溶。分离出了一种对冷休克具有抗性的突变体（CA1），并将其DNA用于枯草芽孢杆菌168AR的转化。转化体（TR1）和CA1几乎完全丧失了主要的营养自溶素（Cw1B和Cw1G）以及运动性，并且在指数生长期呈现出丝状细胞形态。TR1中sigD - lacZ融合蛋白的表达减少。但是将一个过量表达SigD的质粒pHYSigD导入TR1后，自溶素的量显著增加，细胞形态恢复正常（短杆状），并且出现了冷休克敏感表型。然而，转化体的运动性并未恢复。文中讨论了多效性基因在冷休克诱导的自溶中的作用。
