Role of different genes in the CS6 operon for surface expression of Enterotoxigenic Escherichia coli colonization factor CS6.

• Coli surface antigen 6, CS6, is one of the most prevalent colonization factors (CFs) associated with Enterotoxigenic Escherichia coli (ETEC) bacteria, the most common cause of diarrhea among infants and children in developing countries. The CS6 operon encodes two structural subunit proteins, CssA and CssB, a chaperon, CssC, and an usher, CssD. Since little is known about the relationship of the genes and their role in expression and surface assembly of CS6, the operon was cloned into a laboratory E. coli strain, and mutants were constructed by creating deletions in each of the genes. Examination of protein expression by different methods, using monoclonal antibodies with specificities for the individual CS6 structural proteins, suggested that the usher (CssD) was not involved in assembly or surface expression of CS6 whereas deletion of the chaperon (CssC) significantly reduced levels of CssA, but not of CssB. Binding studies with CaCo-2 cells demonstrated that there is a combined effect of CssC and CssD on receptor binding, presumably associated with their activities in assembly and transport of the structural subunits. These findings may have important implications for the construction of strains expressing high levels of CS6 on the surface for eventual use in an ETEC vaccine.

Ämnesord

MEDICIN OCH HÄLSOVETENSKAP  -- Medicinska och farmaceutiska grundvetenskaper -- Mikrobiologi inom det medicinska området (hsv//swe)

MEDICAL AND HEALTH SCIENCES  -- Basic Medicine -- Microbiology in the medical area (hsv//eng)

Nyckelord

Antibodies

Bacterial

metabolism

Antibodies

Monoclonal

metabolism

Antigens

Bacterial

genetics

metabolism

Bacterial Adhesion

Cell Line

Cloning

Molecular

Enterotoxigenic Escherichia coli

genetics

metabolism

Escherichia coli Infections

microbiology

Escherichia coli Proteins

genetics

metabolism

Fimbriae Proteins

genetics

metabolism

Gene Expression Regulation

Bacterial

Genes

Bacterial

Humans

Mutation

Operon

Publikations- och innehållstyp

ref (ämneskategori)

art (ämneskategori)