Journal: International Journal of Molecular Sciences
Article Title: Immunogenicity and Cross-Protective Efficacy Induced by Outer Membrane Proteins from Salmonella Typhimurium Mutants with Truncated LPS in Mice
Figure Lengend Snippet: Schematic molecular model of S. Typhimurium cell wall structure. The Salmonella cell wall comprises the inner membrane, the periplasmic space filled with a gel-like matrix and the outer membrane. The inner membrane is the innermost component, whereas the outer membrane is the outermost impermeable structure, which is a bilayer consisting of a phospholipid layer on the inner side, and a lipopolysaccharide layer towards the outer side, as well as lipoproteins anchored into the membrane. Deletion of the specific gene responsible for lipopolysaccharide (LPS) synthesis would lead to truncation of LPS, thus resulting in the membrane rearrangement and altering the amounts and categories of lipoproteins. The figure represents the types of truncated LPS in this study. (Kdo, 3-deoxy- d -mannooctulosonic acid; PPEtN, pyrophosphorylethanolamine; Hep, heptose; GlcNAc, N -acetylglucosamine; Glc, glucose; Gal, galactose; P, phosphate). Deletion of waaC encoding heptosyltransferase I leads to a deep rough LPS structure carrying only Kdo-lipid A (Re); deletion of waaF encoding heptosyltransferase II results in a mutant generating a LPS structure with lipid A and a truncated inner core (Rd2); deletion of waaG encoding a glycosyltransferase leads to the Rd1 type of LPS lacking the outer core, and consequently, waaI and waaJ mutants produce the truncated core phenotype of Rb3 and Rb2, respectively; deletion of both waaL encoding O -antigen ligase and wbaP encoding Und-P galactose phosphotransferase leads to the production of core-lipid A (Ra) in the mutants; wzy encoding O -antigen polymerase is one of three processing genes, the deletion of which results in a mutant generating a semi-rough LPS carrying a single O -antigen unit with a complete lipid A core, and the deletion of rfaH encoding the transcriptional antiterminator leads to the production of the truncated core phenotype (Rb3).
Article Snippet: Salmonella Typhimurium (S. Typhimurium) and Escherichia coli (E . coli ) were grown in Luria–Bertani (LB) [ ] broth or agar or nutrient broth (Difco, Detroit, MI, USA) at 37 °C.
Techniques: Gas Chromatography, Mutagenesis