title: Both msa genes in Renibacterium salmoninarum are needed for full virulence in bacterial kidney disease.
abstract: Renibacterium salmoninarum, a gram-positive diplococcobacillus that causes bacterial kidney disease among salmon and trout, has two chromosomal loci encoding the major soluble antigen (msa) gene. Because the MSA protein is widely suspected to be an important virulence factor, we used insertion-duplication mutagenesis to generate disruptions of either the msa1 or msa2 gene. Surprisingly, expression of MSA protein in broth cultures appeared unaffected. However, the virulence of either mutant in juvenile chinook salmon (Oncorhynchus tshawytscha) by intraperitoneal challenge was severely attenuated, suggesting that disruption of the msa1 or msa2 gene affected in vivo expression.
authors.affiliation: Northwest Fisheries Science Center, 2725 Montlake Boulevard East, Seattle, WA 98112, USA.
authors.forename: Alison M
authors.initials: AM
authors.lastname: Coady
authors.forename: Anthony L
authors.initials: AL
authors.lastname: Murray
authors.forename: Diane G
authors.initials: DG
authors.lastname: Elliott
authors.forename: Linda D
authors.initials: LD
authors.lastname: Rhodes
mesh_terms: D000193:Actinomycetales Infections / Q000382:microbiology / Q000401:mortality / Q000662:veterinary; D000818:Animals; D000942:Antigens, Bacterial / Q000235:genetics*; D003470:Culture Media; D005393:Fish Diseases / Q000382:microbiology / Q000401:mortality*; D007674:Kidney Diseases / Q000382:microbiology / Q000401:mortality / Q000662:veterinary*; D008835:Micrococcaceae / Q000235:genetics / Q000254:growth & development / Q000472:pathogenicity*; D009154:Mutation; D012474:Salmon / Q000382:microbiology*; D014337:Trout / Q000382:microbiology*; D014774:Virulence
chemical_list: D000942:Antigens, Bacterial; D003470:Culture Media