HEAT-SENSITIVE LAMBDA REPRESSORS RETAIN PARTIAL ACTIVITY DURING BACTERIOPHAGE INDUCTION
HEAT-SENSITIVE LAMBDA REPRESSORS RETAIN PARTIAL ACTIVITY DURING BACTERIOPHAGE INDUCTION
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DOI：
10.1128/jvi.32.1.162-166.1979
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发表时间：
1979-01-01
影响因子：
5.4
通讯作者：
LIEB, M
中科院分区：
文献类型：
--
作者：
LIEB, M
在43度。C，λ cITs原噬菌体被诱导并进入裂解循环[大肠杆菌]。用含有lacZ+基因的λ trp/lac N+cI-噬菌体超感染含有热诱导型λ N-原噬菌体的Lac-溶原菌，所述lacZ+基因的表达受λ cI产物（阻遏物）控制。然后加热溶原，合成β-测定半乳糖苷酶和子代噬菌体的释放。在用λ trp/lac N+，β-半乳糖苷酶比在含有λ N-cIts 857原噬菌体的超感染溶原细胞中出现得更早，合成得更快。即使在45度。C，cI 857阻遏物保留了一些活性。含有产生可复性阻遏物的其它N-cIt突变原噬菌体的溶原在43 ℃也仅部分去阻遏。C.部分去阻遏。早期转染足以诱导λ N+前噬菌体。
At 43.degree. C, .lambda.cITs prophages are induced and enter the lytic cycle [Escherichia coli]. Lac- lysogens containing heat-inducible .lambda.N- prophages were superinfected with a .lambda.trp/lac N+cI- phage containing a lacZ+ gene whose expression is controlled by the .lambda.cI product (repressor). Lysogens were then heated and the synthesis of .beta.-galactosidase and release of progeny phage were measured. In .lambda.N-cITs2 or .lambda.N-cITs16 lysogens superinfected with .lambda.trp/lac N+, .beta.-galactosidase appeared earlier and was synthesized more rapidly than in superinfected lysogens containing .lambda.N-cIts857 prophage. Even at 45.degree. C, the cI857 repressor retained some activity. Lysogens containing other N-cIts mutant prophages producing renaturable repressors were also only partially derepressed at 43.degree. C. Partial derepression of .lambda. early transciption is sufficient for induction of .lambda.N+ prophages.