title: Gene 5.5 protein of bacteriophage T7 inhibits the nucleoid protein H-NS of Escherichia coli.
abstract: Gene 5.5 of coliphage T7 is one of the most highly expressed genes during T7 infection. Gene 5.5 protein, purified from cells overexpressing the cloned gene, purifies with the nucleoid protein H-NS of Escherichia coli during three chromatographic steps. A fusion protein of gene 5.5 protein and maltose binding protein also purifies with H-NS. The fusion protein binds to the DNA-H-NS complex and abolishes H-NS-mediated inhibition of transcription by Escherichia coli and T7 RNA polymerases in vitro. Expression of gene 5.5 also relieves the repression of the Escherichia coli proU promoter by H-NS in vivo. The change of leucine to proline at residue 30 of gene 5.5 protein abolishes the interaction between gene 5.5 protein and H-NS.
authors.affiliation: Department of Biological Chemistry and Molecular Pharmacology, Harvard Medical School, Boston, MA 02115.
authors.forename: Q
authors.initials: Q
authors.lastname: Liu
authors.forename: C C
authors.initials: CC
authors.lastname: Richardson
mesh_terms: D018528:ATP-Binding Cassette Transporters; D001425:Bacterial Outer Membrane Proteins / Q000235:genetics*; D001426:Bacterial Proteins / Q000235:genetics; D001483:Base Sequence; D002352:Carrier Proteins / Q000235:genetics; D004268:DNA-Binding Proteins / Q000235:genetics*; D004926:Escherichia coli / Q000235:genetics*; D029968:Escherichia coli Proteins; D015964:Gene Expression Regulation, Bacterial; D015967:Gene Expression Regulation, Viral; D058619:Maltose-Binding Proteins; D008969:Molecular Sequence Data; D009004:Monosaccharide Transport Proteins; D009838:Oligodeoxyribonucleotides / Q000737:chemistry; D011485:Protein Binding; D012329:RNA, Bacterial / Q000096:biosynthesis; D012333:RNA, Messenger / Q000235:genetics; D011993:Recombinant Fusion Proteins / Q000235:genetics; D013604:T-Phages / Q000235:genetics*; D014158:Transcription, Genetic; D014764:Viral Proteins / Q000235:genetics*
chemical_list: D018528:ATP-Binding Cassette Transporters; D001425:Bacterial Outer Membrane Proteins; D001426:Bacterial Proteins; D002352:Carrier Proteins; D004268:DNA-Binding Proteins; D029968:Escherichia coli Proteins; C031908:H-NS protein, bacteria; D058619:Maltose-Binding Proteins; D009004:Monosaccharide Transport Proteins; D009838:Oligodeoxyribonucleotides; D012329:RNA, Bacterial; D012333:RNA, Messenger; D011993:Recombinant Fusion Proteins; D014764:Viral Proteins; C080078:gene 5.5 protein, Bacteriophage T7; C461599:maltose transport system, E coli