GENETIC-ANALYSIS OF BACTERIOPHAGE-N4 ADSORPTION
GENETIC-ANALYSIS OF BACTERIOPHAGE-N4 ADSORPTION
复制标题
DOI：
10.1128/jb.171.9.4595-4602.1989
复制
发表时间：
1989-09-01
影响因子：
3.2
通讯作者：
ROTHMANDENES, LB
中科院分区：
文献类型：
--
作者：
KIINO, DR;ROTHMANDENES, LB
我们分离了6个突变体的大肠杆菌K-12，是有缺陷的噬菌体N4吸附。我们将突变定位到指定为nfrA至nfrD（N4抗性）的四个基因座。nfrA和nfrB相互紧密连锁，定位于E. coli连锁图谱。nfrC被映射到min 85，并且nfrD被映射在min 44和58之间。我们分离了一个同时携带nfrA和nfrB的克隆，并通过质粒亚克隆的maxicell分析鉴定了其基因产物。nfrA基因产物是表观分子量为96，000的外膜蛋白，而nfrB编码表观分子量为69，500的内膜蛋白。nfrB 1突变不影响nfrA基因产物输出到外膜，也不影响nfrA-phoA融合蛋白的碱性磷酸酶活性。我们建议，nfrA编码的结构受体N4和nfrB基因产物可能需要不可逆的吸附和注射的噬菌体基因组和病毒体封装的RNA聚合酶通过内膜。
We isolated six mutants of Escherichia coli K-12 that were defective in bacteriophage N4 adsorption. We mapped the mutations to four loci designated nfrA through nfrD (N four resistance). nfrA and nfrB were tightly linked to each other and were mapped to min 12 of the E. coli linkage map. nfrC was mapped to min 85, and nfrD was mapped between min 44 and 58. We isolated a clone carrying both nfrA and nfrB and identified its gene products through maxicell analysis of plasmid subclones. The nfrA gene product was an outer membrane protein of 96,000 apparent molecular weight, whereas nfrB encoded and inner-membrane protein of 69,500 apparent molecular weight. The nfrB1 mutation did not affect the export of the nfrA gene product to the outer membrane and did not affect the alkaline phosphatase activity of an nfrA-phoA fusion. We propose that nfrA encodes the structural receptor for N4 and that the nfrB gene product may be required for irreversible adsorption and injection of the phage genome and virion-encapsulated RNA polymerase through the inner membrane.