The genome of Vibrio cholerae, the etiological agent of cholera, is an exception to the single chromosome rule found in the vast majority of bacteria and has its genome partitioned between two unequally sized chromosomes. This unusual two‐chromosome arrangement in V. cholerae has sparked considerable research interest since its discovery. It was demonstrated that the two chromosomes could be fused by deliberate genome engineering or forced to fuse spontaneously by blocking the replication of Chr2, the secondary chromosome. Recently, natural isolates of V. cholerae with chromosomal fusion have been found. Here, we summarize the pertinent findings on this exception to the exception rule and discuss the potential utility of single‐chromosome V. cholerae to address fundamental questions on chromosome biology in general and DNA replication in particular.

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例外规则的例外：合成的和天然存在的单染色体霍乱弧菌

霍乱弧菌（霍乱的病原体）的基因组是在绝大多数细菌中发现的单染色体规则的例外，并且其基因组分配在两个大小不等的染色体之间。V中这种异常的两染色体排列。自发现以来，霍乱已经引起了相当大的研究兴趣。结果表明，两条染色体可以通过有意的基因组工程融合或通过阻止第二染色体Chr2的复制而自发融合。最近，V的天然分离株。霍乱已经发现与染色体融合。在这里，我们总结了与例外规则有关的该例外的相关发现，并讨论了单染色体V的潜在效用。霍乱，以解决一般染色体生物学尤其是DNA复制方面的基本问题。