title: Signature protein of the PVC superphylum.
abstract: The phyla Planctomycetes, Verrucomicrobia, Chlamydiae, Lentisphaerae, and "Candidatus Omnitrophica (OP3)" comprise bacteria that share an ancestor but show highly diverse biological and ecological features. Together, they constitute the PVC superphylum. Using large-scale comparative genome sequence analysis, we identified a protein uniquely shared among all of the known members of the PVC superphylum. We provide evidence that this signature protein is expressed by representative members of the PVC superphylum. Its predicted structure, physicochemical characteristics, and overexpression in Escherichia coli and gel retardation assays with purified signature protein suggest a housekeeping function with unspecific DNA/RNA binding activity. Phylogenetic analysis demonstrated that the signature protein is a suitable phylogenetic marker for members of the PVC superphylum, and the screening of published metagenome data indicated the existence of additional PVC members. This study provides further evidence of a common evolutionary history of the PVC superphylum and presents a unique case in which a single protein serves as an evolutionary link among otherwise highly diverse members of major bacterial groups.
authors.affiliation: Division of Microbial Ecology, Department of Microbiology and Ecosystem Science, University of Vienna, Vienna, Austria.
authors.forename: Ilias
authors.initials: I
authors.lastname: Lagkouvardos
authors.forename: Marc-André
authors.initials: MA
authors.lastname: Jehl
authors.forename: Thomas
authors.initials: T
authors.lastname: Rattei
authors.forename: Matthias
authors.initials: M
authors.lastname: Horn
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D005075:Biological Evolution; D002689:Chlamydia / Q000235:genetics*; D017124:Conserved Sequence; D016680:Genome, Bacterial; D008969:Molecular Sequence Data; D010802:Phylogeny; D061328:Planctomycetales / Q000235:genetics*; D061327:Verrucomicrobia / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins