Capaldo F N, Barbour S D
Basic Life Sci. 1975;5A:405-18. doi: 10.1007/978-1-4684-2895-7_56.
Mutations in the recA, recB, or recC genes significantly reduce the growth rate and viability of Escherichia coli. Cultures of rec- strains are compose of three populations of cells: viable cells, nonviable but residually dividing cells, and nonviable and nondividing cells. Nondividing cells can be separated from dividing cells by penicillin treatment and velocity sedimentation. Nondividing cells of all rec- strains are greatly reduced in their ability to synthesize DNA. recB- recC- and recA- and recB- recC- nondividing cells contain DNA. This DNA synthesized in dividing cells and segregated into the nondividing cells. recA- nondividing cells contain little or no DNA. recA- recB- recC- nondividing cell DNA accumulates single-strand breaks.
recA、recB或recC基因的突变会显著降低大肠杆菌的生长速率和生存能力。rec-菌株的培养物由三类细胞组成：活细胞、无生存能力但仍能分裂的细胞以及无生存能力且不分裂的细胞。通过青霉素处理和速度沉降，可以将不分裂的细胞与分裂细胞分离。所有rec-菌株的不分裂细胞合成DNA的能力都大幅下降。recB- recC-和recA-以及recB- recC-不分裂细胞含有DNA。这种DNA是在分裂细胞中合成并分离到不分裂细胞中的。recA-不分裂细胞几乎不含有或不含有DNA。recA- recB- recC-不分裂细胞的DNA积累单链断裂。
