title: Purification and protein composition of PM2, the first lipid-containing bacterial virus to be isolated.
abstract: The marine, icosahedral bacteriophage PM2 was isolated in the late 1960s. It was the first phage for which lipids were firmly demonstrated to be part of the virion structure and it has been classified as the type organism of the Corticoviridae family. The host, Pseudoalteromonas espejiana BAL-31, belongs to a common group of marine bacteria. We developed a purification method producing virions with specific infectivity approximately as high as that of the lipid-containing phages PRD1 and &phi;6. The sensitivity of the virus to normally used purification media such as those containing sucrose is demonstrated. We also present an alternative host, a pseudoalteromonad, that allows enhanced purification of the virus under reduced salt conditions. We show, using N-terminal amino acid sequencing and comparison with the genomic sequence, that there are at least eight structural proteins in the infectious virus.
authors.affiliation: Institute of Biotechnology, Institute of Biotechnology, Helsinki, Finland.
authors.forename: H M
authors.initials: HM
authors.lastname: Kivelä
authors.forename: R H
authors.initials: RH
authors.lastname: Männistö
authors.forename: N
authors.initials: N
authors.lastname: Kalkkinen
authors.forename: D H
authors.initials: DH
authors.lastname: Bamford
mesh_terms: D000595:Amino Acid Sequence; D001419:Bacteria / Q000145:classification / Q000821:virology; D002122:Calcium Chloride / Q000494:pharmacology; D002501:Centrifugation, Zonal; D002586:Cesium; D002712:Chlorides; D019240:Corticoviridae / Q000737:chemistry* / Q000187:drug effects / Q000254:growth & development / Q000302:isolation & purification*; D016679:Genome, Viral; D005990:Glycerol; D007106:Immune Sera / Q000494:pharmacology; D008055:Lipids / Q000032:analysis*; D008969:Molecular Sequence Data; D008970:Molecular Weight; D012336:RNA, Ribosomal, 16S / Q000032:analysis; D012367:RNA, Viral / Q000032:analysis; D017421:Sequence Analysis; D012965:Sodium Chloride / Q000494:pharmacology; D013395:Sucrose; D013997:Time Factors; D014283:Triiodobenzoic Acids; D015678:Viral Structural Proteins / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification
chemical_list: D002712:Chlorides; D007106:Immune Sera; D008055:Lipids; D012336:RNA, Ribosomal, 16S; D012367:RNA, Viral; D014283:Triiodobenzoic Acids; D015678:Viral Structural Proteins; D002586:Cesium; D012965:Sodium Chloride; D013395:Sucrose; C028019:cesium chloride; C044834:iodixanol; D002122:Calcium Chloride; D005990:Glycerol