Nucleotide sequence encoding the mannose-fucose-resistant hemagglutinin of Vibrio cholerae O1 and construction of a mutant.
The region of DNA encoding the mannose-fucose-resistant hemagglutinin (MFRHA) of Vibrio cholerae O1 has been localized, and the nucleotide sequence has been determined. The region contains a single open reading frame encoding 230 amino acids, corresponding to a protein of 26.9 kDa. The N terminus of this protein is atypical for a protein localized in the outer membrane. A mutant lacking MFRHA activity has been constructed by allelic exchange after inactivation via the insertion of a kanamycin resistance gene cartridge. The MFRHA-negative mutant has been assessed for virulence in the infant mouse cholera model. This mutant shows a marked defect in its ability to persist in the infant mouse gut and is incapable of competing with the wild-type organism, even when given in 25-fold excess. This defect also leads to a > 100-fold increase in the 50% lethal dose. These data suggest that the MFRHA is an important colonization factor in the infant mouse model.
Department of Microbiology and Immunology, University of Adelaide, Australia.
V L
VL
Franzon
A
A
Barker
P A
PA
Manning
D000595:Amino Acid Sequence; D000818:Animals; D001483:Base Sequence; D005643:Fucose / Q000494:pharmacology; D006388:Hemagglutinins / Q000737:chemistry / Q000235:genetics* / Q000633:toxicity; D037102:Lectins; D008358:Mannose / Q000494:pharmacology; D051379:Mice; D008969:Molecular Sequence Data; D009154:Mutation; D014734:Vibrio cholerae / Q000235:genetics* / Q000472:pathogenicity; D014774:Virulence
D006388:Hemagglutinins; D037102:Lectins; C081796:mannose-fucose-resistant hemagglutinin; D005643:Fucose; D008358:Mannose