The deoxyribonucleic acid-modification enzyme of bacteriophage P1. Subunit structure.
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ABSTRACT:
SUBMITTER: Brockes JP
PROVIDER: S-EPMC1177752 | biostudies-other | 1973 Aug
REPOSITORIES: biostudies-other
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Project description:The bacteriophage P1 modification enzyme, assayed by the specific methylation of unmodified bacteriophage 82 DNA, has been purified 500-fold from a bacteriophage P1 lysogen of Escherichia coli. The enzyme catalyses the incorporation of approximately 20-24 methyl groups per bacteriophage 82 DNA molecule. The sole product of methylation is 6-methylaminopurine. Methylation of unmodified bacteriophage DNA confers protection against a challenge by purified bacteriophage P1 restriction enzyme. The pH optimum is 6.0-6.25: the apparent K(m) for S-adenosyl-l-methionine is 5x10(-6)m.
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