Sandler N, Keynan A
Arch Microbiol. 1979 Oct;123(1):9-14. doi: 10.1007/BF00403497.
The sporulation potential of Bacillus subtilis as a function of position in the cell cycle was determined by transferring cells from growth medium to sporulation medium at various times during growth. Growth was induced by incubating heat-activated spores in rich medium or by diluting stationary phase vegetative cultures with fresh growth medium. The results supported earlier observations that sporulation potential is cell cycle dependent. The rise in sporulation potential was studied by exposing cultures to the inhibitors of cell wall and protein synthesis, vancomycin and chloramphenicol. The delay in the appearance of the peak of sporulation potential caused by these inhibitors compared with the reported lack of effect of nalidixic acid, indicates that the appearance of sporulation potential requires synthesis of a macromolecular component other than deoxyribonucleic acid. The effect of nalidixic acid in preventing the decline of the sporulation potential was compared with the effect of high temperature on a mutant temperature sensitive for the initiation of DNA replication. It was found that prevention of chromosome completion with nalidixic acid maintained a high sporulation potential, whereas prevention of chromosome re-initiation in the temperature sensitive mutant did not affect the decline in sporulation potential as the cells enter stationary phase.
通过在生长过程中的不同时间将细胞从生长培养基转移到芽孢形成培养基，测定了枯草芽孢杆菌的芽孢形成潜力与细胞周期位置的函数关系。通过在丰富培养基中培养热激活的孢子或用新鲜生长培养基稀释稳定期营养培养物来诱导生长。结果支持了早期的观察结果，即芽孢形成潜力依赖于细胞周期。通过将培养物暴露于细胞壁和蛋白质合成抑制剂万古霉素和氯霉素来研究芽孢形成潜力的上升。与报道的萘啶酸无作用相比，这些抑制剂导致芽孢形成潜力峰值出现的延迟表明，芽孢形成潜力的出现需要合成除脱氧核糖核酸以外的大分子成分。将萘啶酸防止芽孢形成潜力下降的作用与高温对DNA复制起始敏感的突变体的作用进行了比较。发现用萘啶酸阻止染色体完成可维持较高的芽孢形成潜力，而在温度敏感突变体中阻止染色体重新起始并不影响细胞进入稳定期时芽孢形成潜力的下降。
