title: Serological classification and epitope specificity of Proteus penneri S29 lipopolysaccharide.
abstract: BACKGROUND
  Gram-negative bacteria of genus Proteus are common human intestinal and urinary tract pathogens. In the genus Proteus there are four clinically important named species: P. mirabilis, P. vulgaris, P. penneri, and P. hauseri, and three unnamed Proteus genomospecies: 4, 5, and 6. The clinical significance of P. penneri, described in 1982 as a new species, is poorly documented. The aim of this work is serological characterization and classification of a ceftriaxone-susceptible P. penneri S29 strain isolated from a 34-year-old patient with postneurosurgical meningitis. In this characterization we will also include a ceftriaxonresistant strain, P. penneri R15, isolated from the same patient after 12 days' treatment with ceftriaxon and other antibiotics.
  
  
  METHODS
  Rabbit polyclonal O-antisera were obtained against these two strains and purified and lipopolysaccharides (LPS) were extracted from the bacterial mass of the P. penneri S29 and R15 strains. In the serological investigations the following tests were used: enzyme immunosorbent assay (EIA), passive immunohemolysis (PIH), inhibition of these tests, absorption of rabbit O-antisera with the respective LPS, and repeated PIH, SDS/PAGE, and Western blot techniques.
  
  
  RESULTS
  The serological studies of the LPS extracted from both P. penneri strains showed the identity of both preparations of O-polysaccharides from LPS. In P. penneri S29 O-antiserum, four different types of antibodies were described and characterized.
  
  
  CONCLUSIONS
  Both investigated P. penneri S29 and R15 strains were classified to the Proteus O31ab serogroup.
authors.affiliation: Department of General Microbiology, Institute of Microbiology and Immunology, University of Łódź, Banacha 12/16, 90-237 Łódź, Poland.
authors.forename: Krystyna
authors.initials: K
authors.lastname: Zych
authors.forename: Małgorzata
authors.initials: M
authors.lastname: Siwińska
authors.forename: Zygmunt
authors.initials: Z
authors.lastname: Sidorczyk
mesh_terms: D000328:Adult; D000818:Animals; D002240:Carbohydrate Sequence; D000939:Epitopes; D006801:Humans; D008070:Lipopolysaccharides / Q000737:chemistry / Q000145:classification; D008969:Molecular Sequence Data; D011512:Proteus Infections / Q000276:immunology; D044095:Proteus penneri / Q000737:chemistry / Q000276:immunology*; D011817:Rabbits; D012703:Serotyping
chemical_list: D000939:Epitopes; D008070:Lipopolysaccharides; C430212:lipopolysaccharide, Proteus