Noble M A, Ishiguro E E
Department of Biochemistry and Microbiology, University of Victoria, British Columbia, Canada.
J Gen Microbiol. 1993 Dec;139(12):3109-13. doi: 10.1099/00221287-139-12-3109.
A temperature-sensitive mutation in a new Escherichia coli gene, located at 62.5 min on the linkage map and designated lytF, resulted in bacteriolysis at the restrictive temperature. Temperature sensitivity and lytF-mediated lysis were simultaneously suppressed by either of two previously described unlinked mutations designated smhA1 and smhB1. The smhA1 and smhB1 alleles were originally isolated as specific extragenic suppressors of temperature-sensitive mutations in three other genes known as murH (99 min), lytD (13 min) and lytE (25 min) which conferred lysis phenotypes indistinguishable from that of the lytF mutation. The murH, lytD and lytE genes have been proposed to be related on the bases of phenotypic similarities and the specificities of their extragenic suppressors. It is now further proposed that lytF belongs to this group. The isolation of new alleles of smhA and smhB as extragenic suppressors of lytF further supports this proposal.
位于连锁图谱62.5分钟处的一个新的大肠杆菌基因发生温度敏感突变，该基因被命名为lytF，在限制温度下会导致细菌裂解。温度敏感性和lytF介导的裂解同时被两个先前描述的不连锁突变smhA1和smhB1中的任何一个所抑制。smhA1和smhB1等位基因最初是作为另外三个基因（分别为murH（99分钟）、lytD（13分钟）和lytE（25分钟））中温度敏感突变的特异性基因外抑制子而分离得到的，这三个基因所赋予的裂解表型与lytF突变的表型无法区分。基于表型相似性及其基因外抑制子的特异性，murH、lytD和lytE基因被认为是相关的。现在进一步提出lytF也属于这一组。作为lytF的基因外抑制子分离得到的smhA和smhB新等位基因进一步支持了这一观点。
