title: Site-directed mutagenesis in the DNA linking site of bacteriophage phi 29 terminal protein: isolation and characterization of a Ser232----Thr mutant.
abstract: By site-directed mutagenesis we have changed the serine residue 232 of the phi 29 terminal protein, involved in the covalent linkage to dAMP for the initiation of replication, into a threonine residue. The mutant terminal protein has been purified to homogeneity and shown to be inactive in the formation of the initiation complex; nevertheless, the mutant protein retains its ability to interact with the phi 29 DNA polymerase and with the DNA. The results obtained indicate a high specificity in the linking site of the terminal protein.
mesh_terms: D001435:Bacteriophages / Q000235:genetics*; D004279:DNA, Viral / Q000378:metabolism*; D004268:DNA-Binding Proteins / Q000235:genetics* / Q000378:metabolism; D009154:Mutation; D010957:Plasmids; D012694:Serine; D013912:Threonine; D014764:Viral Proteins / Q000235:genetics* / Q000378:metabolism
chemical_list: D004279:DNA, Viral; D004268:DNA-Binding Proteins; D014764:Viral Proteins; C048231:terminal protein, Streptococcus phage Cp-1; D013912:Threonine; D012694:Serine