title: Effects of internal deletions on the priming activity of the phage phi 29 terminal protein.
abstract: A series of internal deletions of gene 3, coding for the phage phi 29 DNA terminal protein, have been constructed and characterized. In addition, a substitution mutant in the sequence corresponding to amino acids (aa) 49-51 was obtained. The priming activity of the substitution mutant protein, in the formation of the protein p3-dAMP initiation complex, was drastically reduced suggesting that some of the aa present at position 49-51 are essential for p3 function. Deletions of 8 to 33 aa, from aa residue 48 towards the N terminus of the substitution mutant, further decreased the priming activity of the protein. The activity of deletion mutants lacking 15 or 21 aa from residue 57 towards the C terminus, and also containing a point mutation at position 56, was greatly reduced, and no activity was seen when 24 aa were lacking.
authors.affiliation: Centro de Biología Molecular, (CSIC-UAM), Universidad Autónoma, Madrid, Spain.
authors.forename: A
authors.initials: A
authors.lastname: Zaballos
authors.forename: J M
authors.initials: JM
authors.lastname: Lázaro
authors.forename: E
authors.initials: E
authors.lastname: Méndez
authors.forename: R P
authors.initials: RP
authors.lastname: Mellado
authors.forename: M
authors.initials: M
authors.lastname: Salas
mesh_terms: D000595:Amino Acid Sequence; D001412:Bacillus subtilis / Q000235:genetics*; D001435:Bacteriophages / Q000235:genetics*; D001483:Base Sequence; D002872:Chromosome Deletion; D003001:Cloning, Molecular; D004926:Escherichia coli / Q000235:genetics; D005814:Genes, Viral; D008969:Molecular Sequence Data; D009154:Mutation; D015345:Oligonucleotide Probes; D010957:Plasmids; D011401:Promoter Regions, Genetic; D014764:Viral Proteins / Q000096:biosynthesis / Q000235:genetics*; D015678:Viral Structural Proteins / Q000235:genetics*
chemical_list: D015345:Oligonucleotide Probes; D014764:Viral Proteins; D015678:Viral Structural Proteins; C061994:p3 protein, bacteriophage phi 29