title: Purification and DNA-binding activity of the PacA subunit of the bacteriophage P1 pacase enzyme.
abstract: The bacteriophage P1 packaging site (pac) cleavage enzyme (pacase) consists of two phage encoded proteins, PacA and PacB. Both proteins are necessary for the recognition and cleavage of pac and for subsequent packaging of cleaved DNA into phage particles. We have purified PacA to homogeneity from a bacterial strain that overproduces the protein. Purified PacA complements an Escherichia coli extract containing the PacB protein for DNA cleavage at the pac site and recognizes and binds to methylated pac DNA independently of PacB in gel retardation experiments. The latter property of PacA is absolutely dependent on the presence of a wildtype E. coli extract, suggesting that E. coli host proteins play a role in the pac cleavage reaction.
authors.affiliation: DuPont Merck Pharmaceutical Co. Glenolden Laboratory, PA 19036.
authors.forename: K
authors.initials: K
authors.lastname: Skorupski
authors.forename: N
authors.initials: N
authors.lastname: Sternberg
authors.forename: B
authors.initials: B
authors.lastname: Sauer
mesh_terms: D001426:Bacterial Proteins / Q000378:metabolism; D017101:Bacteriophage P1 / Q000201:enzymology* / Q000235:genetics; D001483:Base Sequence; D002853:Chromatography, Liquid; D003001:Cloning, Molecular; D004279:DNA, Viral / Q000378:metabolism; D004268:DNA-Binding Proteins / Q000302:isolation & purification / Q000378:metabolism*; D004706:Endodeoxyribonucleases; D004926:Escherichia coli / Q000378:metabolism; D008969:Molecular Sequence Data; D011994:Recombinant Proteins / Q000302:isolation & purification / Q000378:metabolism; D014764:Viral Proteins / Q000235:genetics / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D001426:Bacterial Proteins; D004279:DNA, Viral; D004268:DNA-Binding Proteins; D011994:Recombinant Proteins; D014764:Viral Proteins; D004706:Endodeoxyribonucleases; C073162:pacase protein, Enterobacteria phage P1