LAMBDA-PHAGEMIDS AND THEIR TRANSDUCING PROPERTIES
LAMBDA-PHAGEMIDS AND THEIR TRANSDUCING PROPERTIES
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DOI：
10.1016/0378-1119(84)90084-2
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发表时间：
1984-01-01
期刊：
影响因子：
3.5
通讯作者：
BAYEV, AA
中科院分区：
文献类型：
--
作者：
MELNIKOV, AA;TCHERNOV, AP;BAYEV, AA
两个重组噬菌体。DNA, .lambda。gt::pMB9和.lambda。构建了分别含有pMB9和pBR322复制子的NM::pBR322，并对其进行了表征。两种构建体（噬菌体DNA）转染大肠杆菌细胞，产生成熟的感染性噬菌体后代。这些噬菌体（吞噬体颗粒）以共价封闭的环状质粒的形式在细胞中维持吞噬体DNA，在感染这些噬菌体（吞噬体颗粒）后，可以选择耐药的转导剂菌落。非溶原性大肠杆菌菌株。lambda的转导效率。噬菌体产生.lambda。根据使用的温度和菌株，阻遏因子cIts的范围为10-7至10-2个转导菌落/输入噬菌体，而。NM::pBR322噬菌体携带imm21转导，频率高达1。这意味着每个.lambda。NM::pBR322噬菌体颗粒能够在细胞中以非致死质粒的形式建立自身，允许形成耐药细菌菌落。.lambda的最大转导水平。gt::pMB9在大肠杆菌细胞溶原。lambda时得到。被使用。因此，转导的效率似乎是由转导剂中噬菌体抑制因子的开启决定的。所有.lambda。gt:：含pMB9的转导剂在一定条件下含有精确切除的pMB9；从.lambda中切除pBR322。未观察到NM::pBR322。
Two recombinant phage .lambda. DNA, .lambda.gt::pMB9 and .lambda.NM::pBR322, containing, respectively, the pMB9 and pBR322 replicon were constructed and characterized. Both constructs (phagemid DNA) transfect Escherichia coli cells, producing mature infectious phage progenies. Drug-resistant colonies of transductants can be selected upon infection with these phages (phagemid particles) that maintain phagemid DNA in the cell in the form of covalently closed circular plasmids. The efficiency of transduction for nonlysogenic E. coli strains with .lambda.gt::pMB9 phage producing .lambda. repressor cIts ranges from 10-7 to 10-2 transductant colonies/input phage, depending on the temperature and strain used, while .lambda.NM::pBR322 phage carrying imm21 transduces with a frequency of up to 1. This means that each .lambda.NM::pBR322 phagemid particle is capable of establishing itself in the cell as a nonlethal plasmid, permitting formation of a resistant bacterial colony. The maximal level of transduction with .lambda.gt::pMB9 was obtained when E. coli cells lysogenic for .lambda. were used. Thus, the efficiency of transduction appears to be determined by the turn-on of the phage repressor in the transductant. All .lambda.gt::pMB9-containing transductants under certain conditions harbor precisely excised pMB9; excision of pBR322 from .lambda.NM::pBR322 was not observed.