Nucleotide sequence of the invasion plasmid antigen B and C genes (ipaB and ipaC) of Shigella flexneri

Microb Pathog. 1988 May;4(5):345-57. doi: 10.1016/0882-4010(88)90062-9.


The nucleotide sequence of a 4.8 kilobase (kb) HindIII fragment from pWR100, the virulence plasmid of Shigella flexneri 5, was determined and analysed. This fragment encodes polypeptides b (62 kilodalton, kD) and c (43 kD) which have already been described as two of the four immunogenic polypeptides of Shigellae. The nucleotide sequence revealed that in addition to the ipaB and ipaC genes encoding polypeptides b and c, a third complete open reading frame was found within the fragment. The gene, named ippI, encoded a 17 kD polypeptide. The deduced amino acids sequence of polypeptides b and c showed no signal peptide but presence of highly hydrophobic domains compatible with a transmembraneous location. The surprising A and T richness of the three genes as compared with the Escherichia coli and Shigella genomes, resulted in a biased codon usage, and raises the question of the origin of the sequences.

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Amino Acid Sequence
  • Antigens, Bacterial / genetics*
  • Base Sequence
  • Cloning, Molecular
  • Codon / genetics
  • DNA, Bacterial / genetics*
  • Genes, Bacterial
  • Immunoblotting
  • Molecular Sequence Data
  • Peptides / genetics
  • Peptides / immunology
  • Plasmids
  • Restriction Mapping
  • Shigella flexneri / genetics*
  • Shigella flexneri / immunology
  • Shigella flexneri / pathogenicity
  • Virulence


  • Antigens, Bacterial
  • Codon
  • DNA, Bacterial
  • Peptides