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Functional and structural characterization of chimeras of a bacterial genotoxin and human type I DNAse.

ABSTRACT: Chimeras composed of the cdtB gene of a novel bacterial genotoxin and the human type I DNAse I gene were constructed and their products characterized relative to the biochemical and enzymatic properties of the native proteins. The product of a cdtB/DNAse I chimera formed a heterotrimer with the CdtA and CdtC subunits of the genotoxin, and targeted mutations increased the specific activity of the hybrid protein. Expression of active chimeric gene products established that the CdtB protein is an atypical divalent cation-dependent endonuclease and demonstrated the potential for genetically engineering a new class of therapeutic agent for inhibiting the proliferation of cancer cells.

SUBMITTER: DiRienzo JM

PROVIDER: S-EPMC3523320 | biostudies-literature | 2009 Feb

REPOSITORIES: biostudies-literature

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Functional and structural characterization of chimeras of a bacterial genotoxin and human type I DNAse.

DiRienzo Joseph M JM Cao Linsen L Volgina Alla A Bandelac Georges G Korostoff Jonathan J

FEMS microbiology letters 20081211 2

Chimeras composed of the cdtB gene of a novel bacterial genotoxin and the human type I DNAse I gene were constructed and their products characterized relative to the biochemical and enzymatic properties of the native proteins. The product of a cdtB/DNAse I chimera formed a heterotrimer with the CdtA and CdtC subunits of the genotoxin, and targeted mutations increased the specific activity of the hybrid protein. Expression of active chimeric gene products established that the CdtB protein is an a ...[more]

PMID: 19087203

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