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An expression-packaging-processing vector which selects and maintains 7-kb DNA inserts in the blue T4 phage genome.

Y R Hong·L W Black
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Abstract

We have developed an efficient positive-selection vector to insert foreign DNA segments fused to the T4 ipIII gene (encoding internal protein IPIII) into the bacteriophage T4 genome. By using partial deletions of the T4 e gene, which encodes phage lysozyme, lysozyme activity required for plaque formation is used to select plasmid integrants which restore the e gene. In this work, we demonstrate that DNA inserts more than 7.0 kb in length can be incorporated into a T4 genome lacking the alt gene. In addition, the recombinant T4 not only contains a fusion gene driven by the T4 ipIII promoters, but also packages the fusion protein into the T4 capsid due to targeting by the IPIII portion. This expression-packaging-processing system shows that active IPIII::beta Gal fusion reporter protein is produced and packaged during phage infection.

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Bacteriophage T4Blotting, SouthernCapsidCapsid ProteinsGenes, ViralGenetic VectorsLac OperonMuramidasePhenotypeRecombination, GeneticRestriction MappingJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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Y R Hong, L W Black. 1993-12-22. An expression-packaging-processing vector which selects and maintains 7-kb DNA inserts in the blue T4 phage genome.. https://doi.org/10.1016/0378-1119(93)90463-d

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