title: A typhus group-specific protease defies reductive evolution in rickettsiae.
abstract: Phylogenomics reveals extreme gene loss in typhus group (TG) rickettsiae relative to the levels for other rickettsial lineages. We report here a curious protease-encoding gene (ppcE) that is conserved only in TG rickettsiae. As a possible determinant of host pathogenicity, ppcE warrants consideration in the development of therapeutics against epidemic and murine typhus.
authors.affiliation: Department of Microbiology and Immunology, University of Maryland School of Medicine, Baltimore, Maryland 21201, USA.
authors.forename: Nicole C
authors.initials: NC
authors.lastname: Ammerman
authors.forename: Joseph J
authors.initials: JJ
authors.lastname: Gillespie
authors.forename: Andrew F
authors.initials: AF
authors.lastname: Neuwald
authors.forename: Bruno W
authors.initials: BW
authors.lastname: Sobral
authors.forename: Abdu F
authors.initials: AF
authors.lastname: Azad
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics*; D017124:Conserved Sequence; D019143:Evolution, Molecular; D008958:Models, Molecular; D008969:Molecular Sequence Data; D010802:Phylogeny; D017434:Protein Structure, Tertiary; D016996:Rickettsieae / Q000201:enzymology* / Q000235:genetics*; D016415:Sequence Alignment; D012697:Serine Endopeptidases / Q000235:genetics*
chemical_list: D001426:Bacterial Proteins; D012697:Serine Endopeptidases; C020832:group-specific protease