title: Profiling of virulence associated genes of Pasteurella multocida isolated from cattle.
abstract: Pasteurella multocida is a causative agent of many major diseases of which haemorrhagic septiciemia (HS) in cattle & a buffalo is responsible for significant losses to livestock sector in India and south Asia. The disease outcome is affected by various host- and pathogen-specific determinants. Several bacterial species-specific putative virulence factors including the capsular and virulence associated genes have been proposed to play a key role in this interaction. A total of 23 isolates of P. multocida were obtained from 335 cases of various clinically healthy and diseased cattle. These isolates were examined for capsule synthesis genes (capA, B, D, E and F) and eleven virulence associated genes (tbpA, pfhA, toxA, hgbB, hgbA, nanH, nanB, sodA, sodC, oma87 and ptfA) by PCR. A total of 19 P. multocida isolates belonging to capsular type B and 4 of capsular type A were isolated. All isolates of capsular type B harboured the virulence associated genes: tbpA, pfhA, hgbA, sodC and nanH, coding for transferrin binding protein, filamentous hemagglutinin, haemoglobin binding protein, superoxide dismutase and neuraminidases, respectively; while isolates belonging to capsular type A also carried tbpA, pfhA, hgbA and nanH genes. Only 50 % of capsular type A isolates contained sodC gene while 100 % of capsular type B isolates had sodC gene. The gene nanB and toxA were absent in all the 23 isolates. In capsular type A isolates, either sodA or sodC gene was present & these genes did not occur concurrently. The presence of virulence associated gene ptfA revealed a positive association with the disease outcome in cattle and could therefore be an important epidemiological marker gene for characterizing P. multocida isolates.
authors.affiliation: Department of Veterinary Microbiology, Dr. G.C. Negi College of Veterinary & Animal Sciences, CSK Himachal Pradesh Agricultural University, Palampur, Himachal Pradesh, 176062, India. sverma8@yahoo.co.uk
authors.forename: Subhash
authors.initials: S
authors.lastname: Verma
authors.forename: Mandeep
authors.initials: M
authors.lastname: Sharma
authors.forename: Shailja
authors.initials: S
authors.lastname: Katoch
authors.forename: Lovit
authors.initials: L
authors.lastname: Verma
authors.forename: Sandeep
authors.initials: S
authors.lastname: Kumar
authors.forename: Vishal
authors.initials: V
authors.lastname: Dogra
authors.forename: Rajesh
authors.initials: R
authors.lastname: Chahota
authors.forename: Prasenjit
authors.initials: P
authors.lastname: Dhar
authors.forename: Geetanjali
authors.initials: G
authors.lastname: Singh
mesh_terms: D000818:Animals; D002417:Cattle; D002418:Cattle Diseases / Q000453:epidemiology / Q000382:microbiology*; D004269:DNA, Bacterial / Q000235:genetics* / Q000378:metabolism; D005798:Genes, Bacterial; D007194:India; D010326:Pasteurella Infections / Q000453:epidemiology / Q000382:microbiology / Q000662:veterinary*; D016979:Pasteurella multocida / Q000145:classification / Q000235:genetics* / Q000302:isolation & purification / Q000472:pathogenicity*; D016133:Polymerase Chain Reaction / Q000662:veterinary; D017422:Sequence Analysis, DNA / Q000662:veterinary; D014774:Virulence; D037521:Virulence Factors / Q000235:genetics* / Q000378:metabolism
chemical_list: D004269:DNA, Bacterial; D037521:Virulence Factors