In this study we have compared protein secretion in the wild type of S. Typhimurium and the rfaC mutant. We found out that the rfaC mutant was defective in protein secretion. In addition, the rfaC mutant was defective in its invasion into an IPEC-J2 porcine epithelial cell line and also in motility in semisolid agar. Consistent with this, reduced flagella numbers were observed in the rfaC mutant. In the rfaC mutant, there were no defects in flagellin expression as detected by western blot and immune electron microscopy which demonstrated equal amounts of flagellin in the cytoplasm of both the rfaC mutant and the wild-type S. Typhimurium. However, in the wild-type strain only, the flagellin was assembled to spatially restricted areas on the inner side of cytoplasmic membrane. The oligosaccharide core of LPS is therefore required for the assembly of flagella and T3SS secretion machinery followed by protein secretion.

• MeSH
• Bacterial Secretion Systems MeSH
• Cell Line MeSH
• Cytoplasm chemistry   MeSH
• Epithelial Cells microbiology   MeSH
• Flagellin biosynthesis   secretion   MeSH
• Flagella metabolism   MeSH
• Microscopy, Immunoelectron MeSH
• Lipopolysaccharides chemistry   MeSH
• Mutation MeSH
• Swine MeSH
• Salmonella enterica genetics   metabolism   ultrastructure   MeSH
• Oligonucleotide Array Sequence Analysis MeSH
• Animals MeSH
• Check Tag
• Animals MeSH
• Publication type
• Journal Article MeSH
• Research Support, Non-U.S. Gov't MeSH

• Publication type
• Meeting Abstract MeSH