Rescue of the orphan enzyme isoguanine deaminase.
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ABSTRACT:
SUBMITTER: Hitchcock DS
PROVIDER: S-EPMC3138507 | biostudies-literature | 2011 Jun
REPOSITORIES: biostudies-literature
Publications
Rescue of the orphan enzyme isoguanine deaminase.
Hitchcock Daniel S DS Fedorov Alexander A AA Fedorov Elena V EV Dangott Lawrence J LJ Almo Steven C SC Raushel Frank M FM
Biochemistry 20110607 25
Cytosine deaminase (CDA) from Escherichia coli was shown to catalyze the deamination of isoguanine (2-oxoadenine) to xanthine. Isoguanine is an oxidation product of adenine in DNA that is mutagenic to the cell. The isoguanine deaminase activity in E. coli was partially purified by ammonium sulfate fractionation, gel filtration, and anion exchange chromatography. The active protein was identified by peptide mass fingerprint analysis as cytosine deaminase. The kinetic constants for the deamination ...[more]
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