Jaffé A, Boye E, D'Ari R
Institut Jacques Monod, Université Paris 7, France.
J Bacteriol. 1990 Jun;172(6):3500-2. doi: 10.1128/jb.172.6.3500-3502.1990.
Escherichia coli minB mutants form anucleate minicells and multinucleate filaments. We show here that the overwhelming majority of nucleate cells contain 2n (n = 0, 1, 2, ...) nucleoids, as determined by 4',6-diamidino-2-phenylindole staining, and 2n (n = 1, 2, 3, ...) copies of the replication origin, as determined by flow cytometry. This shows that division sites are not chosen randomly among the available sites in minB filaments. Similarly, wild-type cells contain 2n nucleoids, both during cell division inhibition and when furazlocillin-induced filaments are allowed to divide. We conclude that the min+ function is only to prevent septation only at polar sites; the placement of internal cell division sites must obey strict rules, which are the same in minB and wild-type cells.
大肠杆菌minB突变体形成无核小细胞和多核丝状体。我们在此表明，绝大多数有核细胞含有2n（n = 0、1、2……）个类核体，这是通过4',6-二脒基-2-苯基吲哚染色确定的，并且含有2n（n = 1、2、3……）个复制起点拷贝，这是通过流式细胞术确定的。这表明在minB丝状体中，分裂位点并非在可用位点中随机选择。同样，野生型细胞在细胞分裂受抑制期间以及当允许呋咱洛西林诱导的丝状体进行分裂时，都含有2n个类核体。我们得出结论，min+功能仅在于防止仅在极性位点形成隔膜；内部细胞分裂位点的定位必须遵循严格规则，这些规则在minB细胞和野生型细胞中是相同的。
