title: Crystallization and preliminary X-ray diffraction analysis of bacteriophage varphi12 packaging factor P7.
abstract: Bacteriophage varphi12 protein P7 is a structural component of the polymerase complex and ensures stable packaging of the genomic RNA. varphi12 P7 has been cloned, purified and crystallized. Crystals belong to space group P3(2)21, with unit-cell parameters a = 75.7, b = 75.7, c = 45.2 A, alpha = 90, beta = 90, gamma = 120 degrees , and diffract beyond 2.0 A. Multiple anomalous dispersion data have been collected from crystals of selenomethionylated P7. Mass spectroscopy showed proteolysis of the crystallized protein and a truncated form, P7DeltaC, gave crystals of similar morphology. Cross-linking experiments implicated the N-terminal domain of P7 as being essential for dimerization.
authors.affiliation: Institute of Biotechnology and Faculty of Biosciences, Viikki Biocenter, PO Box 56, Viikinkaari 5, University of Helsinki, FIN-00014 Helsinki, Finland.
authors.forename: Denis E
authors.initials: DE
authors.lastname: Kainov
authors.forename: Vladimir
authors.initials: V
authors.lastname: Simonov
authors.forename: Dennis H
authors.initials: DH
authors.lastname: Bamford
authors.forename: Roman
authors.initials: R
authors.lastname: Tuma
authors.forename: Paul
authors.initials: P
authors.lastname: Gottlieb
authors.forename: Hui
authors.initials: H
authors.lastname: Wei
authors.forename: Martin A
authors.initials: MA
authors.lastname: Walsh
authors.forename: Hassan
authors.initials: H
authors.lastname: Belrhali
authors.forename: Michael C
authors.initials: MC
authors.lastname: Merckel
mesh_terms: D001435:Bacteriophages / Q000378:metabolism*; D002850:Chromatography, Gel; D003001:Cloning, Molecular; D003432:Cross-Linking Reagents / Q000494:pharmacology; D003460:Crystallization; D018360:Crystallography, X-Ray; D019281:Dimerization; D006026:Glycoside Hydrolases / Q000737:chemistry*; D013058:Mass Spectrometry; D017434:Protein Structure, Tertiary; D012313:RNA / Q000737:chemistry; D012645:Selenomethionine / Q000737:chemistry; D013997:Time Factors; D017361:Viral Nonstructural Proteins / Q000737:chemistry*; D014961:X-Ray Diffraction
chemical_list: D003432:Cross-Linking Reagents; D017361:Viral Nonstructural Proteins; D012313:RNA; D012645:Selenomethionine; D006026:Glycoside Hydrolases; C443982:P7 protein, bacteriophage PRD1