Salmonella typhimurium (S. typhimurium) belongs to the family Enterobacteriaceae. S. typhimurium is a pathogenic Gram-negative bacteria predominately found in the intestinal lumen. It is a serotype of over 2500 serotypes of Salmonella enterica which causes gastroenteritis or inflammation of the gut and its infection incidence ranks first among Salmonella infections, accounting for about 40%~80% of human Salmonella infections. Gastroenteritis leads to diarrhea, vomiting, fever, and abdominal cramps.
Figure 1. Image of S. typhimurium (Joe, 2019)
The toxicity of S. typhimurium is due to an outer membrane consisting largely of lipopolysaccharides (LPS) which protect the bacteria from the environment. The LPS is made up of an O-antigen, a polysaccharide core, and lipid A, which connects it to the outer membrane. Lipid A is made up of two phosphorylated glucosamines which are attached to fatty acids. These phosphate groups determine bacterial toxicity. Animals carry an enzyme that specifically removes these phosphate groups in an attempt to protect themselves from these pathogens. The O-antigen, being on the outermost part of the LPS complex is responsible for the host immune response. S. typhimurium has the ability to undergo acetylation of this O-antigen, which changes its conformation, and makes it difficult for antibodies to recognize.
Figure 2. S. typhimurium pathogenesis (Brugiroux, 2016)
S. typhimurium has been used to investigate its ability to deliver DNA to antigen presenting cells (APCs) in order to produce cancer vaccines. Studies indicate that S. typhimurium has been able to initiate an immune response as a direct result of the DNA containing "eukaryotic expression vectors". Mice exhibit typhoid like symptoms when infected with S. typhimurium and are currently being used to develop a typhoid vaccine. Creative Diagnostics now can provide multiple high-quality S. typhimurium antigens to our customers with a cheaper price for various applications in both industry and academic programs. Welcome to contact us for more details.
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