A typhus group-specific protease defies reductive evolution in rickettsiae

J Bacteriol. 2009 Dec;191(24):7609-13. doi: 10.1128/JB.01077-09. Epub 2009 Oct 9.


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.

Publication types

  • Research Support, N.I.H., Extramural

MeSH terms

  • Amino Acid Sequence
  • Bacterial Proteins / genetics*
  • Conserved Sequence
  • Evolution, Molecular*
  • Models, Molecular
  • Molecular Sequence Data
  • Phylogeny
  • Protein Structure, Tertiary
  • Rickettsieae / enzymology*
  • Rickettsieae / genetics*
  • Sequence Alignment
  • Serine Endopeptidases / genetics*


  • Bacterial Proteins
  • Serine Endopeptidases
  • group-specific protease