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PubMed · 702651

Anomalous behavior of bacteriophage lambda polypeptides in polyacrylamide gels: resolution, identification, and control of the lambda rex gene product.

M Belfort
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Abstract

The resolution of lambia proteins was compared on the two types of sodium dodecyl sulfate-polyacrylamide gels commonly in use. The two kinds of gel differ essentially in the ratio of the cross-linker, N'-N-bismethylene-acrylamide (bisacrylamide), to acrylamide monomer. Several lambda proteins migrate relatively more slowly in gels with high bisacrylamide/acrylamide ratios (HB gels) than in gels with low ratios, although the two types of gel are of roughly equivalent porosity. This effect is illustrated by a change in relative position of both the Rex and Int proteins, with apparent increases in molecular weight of about 8 and 15%, respectively, in the HB gels. This work confirms that like repressor and Int, the 28.5-kilodalton protein, identified as Rex on HB gels, is postively regulated by the lambdacII and cIII products and negatively controlled Cro. An intact y site is required for Rex and repressor expression after infection, whereas their synthesis in a lysogen is dependent upon a functional maintenance promoter, Prm.

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ColiphagesElectrophoresis, Polyacrylamide GelGenes, RegulatorGenes, ViralLysogenyMutationPeptidesViral ProteinsComparative StudyJournal Article

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M Belfort. 1978. Anomalous behavior of bacteriophage lambda polypeptides in polyacrylamide gels: resolution, identification, and control of the lambda rex gene product.. https://doi.org/10.1128/jvi.28.1.270-278.1978

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