Norioka N, Hsu M Y, Inouye S, Inouye M
Department of Biochemistry, Robert Wood Johnson Medical School, Piscataway, New Jersey 08854, USA.
J Bacteriol. 1995 Jul;177(14):4179-82. doi: 10.1128/jb.177.14.4179-4182.1995.
Two recA genes, recA1 and recA2, in Myxococcus xanthus were cloned by using the recA gene of Escherichia coli, and their DNA sequences were determined. On the basis of deduced amino acid sequences, RecA1 and RecA2 have 67.0% identity to each other and 60.5 and 60.9% identities to E. coli RecA, respectively. Expression of recA2 was detected in both vegetative and developmental cells by Northern blot (RNA) analysis, and a threefold induction was observed when cells were treated with nalidixic acid. Repeated attempts to isolate a recA2 disruption mutant have failed, while a recA1 disruption mutant was readily isolated. Both the recA1 and recA2 genes expressed in E. coli complement the UV sensitivity of an E. coli recA strain.
利用大肠杆菌的recA基因克隆了黄色粘球菌中的两个recA基因recA1和recA2，并测定了它们的DNA序列。根据推导的氨基酸序列，RecA1和RecA2彼此之间的同一性为67.0%，与大肠杆菌RecA的同一性分别为60.5%和60.9%。通过Northern印迹（RNA）分析在营养细胞和发育细胞中均检测到recA2的表达，当用萘啶酸处理细胞时观察到三倍的诱导。多次尝试分离recA2缺失突变体均失败，而recA1缺失突变体很容易分离。在大肠杆菌中表达的recA1和recA2基因均能互补大肠杆菌recA菌株的紫外线敏感性。
