The recombinant suicide plasmid pYYvpr contained a Kan resistant cassette and a 778bp internal piece of the vpr gene. It was transformed into the wild type E.coli strain, MC 1061,which possessed the full-length vpr ge...The recombinant suicide plasmid pYYvpr contained a Kan resistant cassette and a 778bp internal piece of the vpr gene. It was transformed into the wild type E.coli strain, MC 1061,which possessed the full-length vpr gene and did not contain the λ pir gene. The recombinant suicide plasmid could not replicate in MC 1061. Colonies grew on the plates of Kan were analysed by PCR and Southern blot with two different Dig-probes,vpr and Kan R probes. One colony was detected vpr and Kan R gene by PCR and Southern blot showed the mutant had the different vpr map with the wild type. The isogenic knockout mutant, named MC1061 Δvpr,was confirmed.The mutant supported lysogenic infection of VT2 recombinant phage, but did not support lytic infection. All results showed that the vpr gene should be related to the lytic infection of VT2 phage.展开更多
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文摘The recombinant suicide plasmid pYYvpr contained a Kan resistant cassette and a 778bp internal piece of the vpr gene. It was transformed into the wild type E.coli strain, MC 1061,which possessed the full-length vpr gene and did not contain the λ pir gene. The recombinant suicide plasmid could not replicate in MC 1061. Colonies grew on the plates of Kan were analysed by PCR and Southern blot with two different Dig-probes,vpr and Kan R probes. One colony was detected vpr and Kan R gene by PCR and Southern blot showed the mutant had the different vpr map with the wild type. The isogenic knockout mutant, named MC1061 Δvpr,was confirmed.The mutant supported lysogenic infection of VT2 recombinant phage, but did not support lytic infection. All results showed that the vpr gene should be related to the lytic infection of VT2 phage.