title: Acid pre-adaptation enhances virulence of Salmonella enterica serovar Typhimurium dam mutant.
abstract: It is well established that success or failure of bacterial pathogens during infection relies upon its ability to overcome many lethal environments in the host such as acidity, osmolarity and bile salts. In the present study, we have studied the effects of acid adaptation on the virulence of Salmonella enterica serovar Typhimurium dam mutant. Our results indicated that LD(50) of adapted strains were lower than those of control strains. Also, the in vivo assays have shown that the development of a systemic infection is slower for control strains than for adapted strains. In addition, the number of acid-adapted mutants colonizing spleen and liver is higher than control strains. Adhesion and invasion experiments were performed in order to compare the pathogenicity of Salmonella. No significant differences were shown between pre-treated and non-adapted strains. According to these results, we report that acid adaptation of Salmonella enterica serovar Typhimurium dam mutants can increase their in vivo virulence in mice.
authors.affiliation: Unité de biochimie des lipides et interaction des macromolécules en biologie 03/UR/0902, laboratoire de biochimie et biologie moléculaire, département des sciences de la vie, faculté des sciences de Bizerte, Zarzouna 7021, Tunisia. chattiabdel@yahoo.fr
authors.forename: C
authors.initials: C
authors.lastname: Abdelwaheb
authors.forename: L
authors.initials: L
authors.lastname: Ahmed
mesh_terms: D000143:Acids / Q000494:pharmacology*; D000222:Adaptation, Physiological; D000818:Animals; D001426:Bacterial Proteins / Q000502:physiology*; D003470:Culture Media / Q000737:chemistry / Q000494:pharmacology; D019175:DNA Methylation / Q000187:drug effects; D004269:DNA, Bacterial / Q000737:chemistry / Q000235:genetics; D005260:Female; D006863:Hydrogen-Ion Concentration; D007928:Lethal Dose 50; D008099:Liver / Q000382:microbiology; D051379:Mice; D012481:Salmonella Infections, Animal / Q000382:microbiology*; D012486:Salmonella typhimurium / Q000187:drug effects* / Q000201:enzymology / Q000254:growth & development / Q000472:pathogenicity; D015265:Site-Specific DNA-Methyltransferase (Adenine-Specific) / Q000502:physiology*; D013154:Spleen / Q000382:microbiology; D014774:Virulence / Q000187:drug effects / Q000235:genetics
chemical_list: D000143:Acids; D001426:Bacterial Proteins; D003470:Culture Media; D004269:DNA, Bacterial; C058693:Dam methyltransferase; D015265:Site-Specific DNA-Methyltransferase (Adenine-Specific)