Nucleotide sequence of the invasion plasmid antigen B and C genes (ipaB and ipaC) of Shigella flexneri.
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.
Baudry
B
B
Service des Entérobactéries, Unité INSERM 199, Institut Pasteur, Paris, France.
Kaczorek
M
M
Sansonetti
P J
PJ
D000595:Amino Acid Sequence; D000942:Antigens, Bacterial / Q000235:genetics*; D001483:Base Sequence; D003001:Cloning, Molecular; D003062:Codon / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics*; D005798:Genes, Bacterial; D015151:Immunoblotting; D008969:Molecular Sequence Data; D010455:Peptides / Q000235:genetics / Q000276:immunology; D010957:Plasmids; D015183:Restriction Mapping; D012763:Shigella flexneri / Q000235:genetics* / Q000276:immunology / Q000472:pathogenicity; D014774:Virulence
D000942:Antigens, Bacterial; D003062:Codon; D004269:DNA, Bacterial; D010455:Peptides