pGMB151自殺質(zhì)粒

pGMB151 is a derivative of the suicide plasmid pKNG101 and includes oriR6K, RP4, sacBR, insB, and strAB

with the bla gene from plasmid pBR322 cloned at the Xba I site. It is a suicide plasmid because of its requirement for the pir protein, which is supplied by kpir in certain strains of Escherichia coli, such as SM10.

To improve the efficiency of allelic exchange for genome genetic modification,

a novel pGMB152 vector was constructed with the

lacZYA operon incorporated into pGMB151 to provide

LacZ-based blue–white selection. The LacZ gene, a

well-known reporter gene expressing b-galactosidase, can

provide blue–white selection to make the existence of

molecular cloning visible  and could be used as a

biomarker for the suicide plasmid. Bacteria colonies with

pGMB152 will show as blue and those without pGMB152

will show as white; therefore, bacterial colonies with different

colors could be distinguished easily during the different

processes of genome genetic modification. The new

plasmid was used to knock out the hsdM gene [9] in Salmonella

pullorum to construct a candidate-attenuated Salmonella

vaccine, to repair pseudogene flhA by knockin and

pseudogene flgk by site-directed mutagenesis.

BioVector NTCC質(zhì)粒載體菌種細(xì)胞基因保藏中心