Emergence of novel Streptococcus iniae exopolysaccharide-producing strains following vaccination with nonproducing strains.
Streptococcus iniae is a major pathogen of fish, producing fatal disease among fish species living in very diverse environments. Recently, reoccurrences of disease outbreaks were recorded in rainbow trout (Oncorhynchus mykiss, Walbaum) farms where the entire fish population was routinely vaccinated. New strains are distinguished from previous strains by their ability to produce large amounts of extracellular polysaccharide that is released into the medium. Present findings indicate that the extracellular polysaccharide is a major antigenic factor, suggesting an evolutionary selection of strains capable of extracellular polysaccharide production.
Eyngor
Marina
M
Institute of Biochemistry, Food Science and Nutrition, Faculty of Agricultural, Food and Environmental Quality Sciences, The Hebrew University of Jerusalem, Rehovot 76100, Israel.
Tekoah
Yoram
Y
Shapira
Roni
R
Hurvitz
Avshalom
A
Zlotkin
Amir
A
Lublin
Avishay
A
Eldar
Avi
A
D000818:Animals; D005393:Fish Diseases / Q000276:immunology / Q000382:microbiology*; D017686:Oncorhynchus mykiss / Q000276:immunology / Q000382:microbiology; D011135:Polysaccharides, Bacterial / Q000378:metabolism*; D013290:Streptococcal Infections / Q000276:immunology / Q000382:microbiology / Q000662:veterinary*; D022541:Streptococcal Vaccines / Q000008:administration & dosage / Q000276:immunology*; D013291:Streptococcus / Q000276:immunology* / Q000378:metabolism*
D011135:Polysaccharides, Bacterial; D022541:Streptococcal Vaccines