The mechanism of replication of phiX174. XVII. Purification and partial characterization of the gene A and A proteins.
A simple method for purifying the gene A plus A* proteins of bacteriophage phiX174 is presented. The proteins are relatively hydrophobic and precipitate from aqueous solution at low ionic strength. The gene A plus A* protein preparation was able to stimulate phi X DNA replication in vitro and was able to neck supercoiled phiX replicative form 1 to produce unit-length linear and circular strands of DNA. The kinetics of the nicking reaction were more consistent with a stoichiometric than with a catalytic mechanism. Under nondenaturing conditions the presumably globular A and A* protein sedimented with apparent molecular weights of 110 000 and 90 000.
D010584:Bacteriophage phi X 174 / Q000235:genetics / Q000378:metabolism*; D004261:DNA Replication; D004279:DNA, Viral / Q000096:biosynthesis; D005814:Genes, Viral; D007700:Kinetics; D008970:Molecular Weight; D014764:Viral Proteins / Q000302:isolation & purification* / Q000378:metabolism; D014779:Virus Replication
D004279:DNA, Viral; D014764:Viral Proteins