title: The contribution of aerobic and anaerobic respiration to intestinal colonization and virulence for Salmonella typhimurium in the chicken.
abstract: The basic mechanism whereby Salmonella serovars colonize the chicken intestine remains poorly understood. Previous studies have indicated that proton-translocating proteins utilizing oxygen as terminal electron acceptor do not appear to be of major importance in the gut of the newly hatched chicken and consequently they would be even less significant during intestinal colonization of more mature chickens where the complex gut microflora would trap most of the oxygen in the lumen. Consequently, alternative electron acceptors may be more significant or, in their absence, substrate-level phosphorylation may also be important to Salmonella serovars in this environment. To investigate this we constructed mutants of Salmonella enterica serovar Typhimurium defective in various aspects of oxidative or substrate-level phosphorylation to assess their role in colonization of the chicken intestine, assessed through faecal shedding, and virulence. Mutations affecting use of oxygen or alternative electron acceptors did not eliminate faecal shedding. By contrast mutations in either pta (phosphotransacetylase) or ackA (acetate kinase) abolished shedding. The pta but not the ackA mutation also abolished systemic virulence for chickens. An additional ldhA (lactate dehydrogenase) mutant also showed poor colonizing ability. We hypothesise that substrate-level phosphorylation may be more important than respiration using oxygen or alternative electron acceptors for colonization of the chicken caeca.
authors.affiliation: a School of Veterinary Medicine and Science , University of Nottingham , Loughborough , UK.
authors.forename: Paul Andrew
authors.initials: PA
authors.lastname: Barrow
authors.affiliation: b Departament of Veterinary Pathology, Faculdade de Ciências Agrárias e Veterinárias , Univ Estadual Paulista , São Paulo , Brazil.
authors.forename: Angelo
authors.initials: A
authors.lastname: Berchieri
authors.affiliation: c Department of Veterinary Sciences , Federal University of Paraíba , Paraíba , Brazil.
authors.forename: Oliveiro Caetano de
authors.initials: OC
authors.lastname: Freitas Neto
authors.affiliation: a School of Veterinary Medicine and Science , University of Nottingham , Loughborough , UK.
authors.forename: Margaret
authors.initials: M
authors.lastname: Lovell
mesh_terms: D000332:Aerobiosis; D000693:Anaerobiosis; D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D002645:Chickens; D004195:Disease Models, Animal; D004198:Disease Susceptibility; D007422:Intestines / Q000382:microbiology; D007770:L-Lactate Dehydrogenase / Q000235:genetics; D009154:Mutation; D010100:Oxygen / Q000378:metabolism*; D010709:Phosphate Acetyltransferase / Q000235:genetics; D010766:Phosphorylation; D011201:Poultry Diseases / Q000382:microbiology*; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000235:genetics / Q000502:physiology*; D013047:Specific Pathogen-Free Organisms; D014774:Virulence
chemical_list: D001426:Bacterial Proteins; D007770:L-Lactate Dehydrogenase; D010709:Phosphate Acetyltransferase; D010100:Oxygen