Protein alignment reveals a conserved structure of the sucrose-specific IIB domain of the PTS system gene in Vibrio cholerae strains.

Comparative amino-acid alignment of the sucrose-specific IIB domain of the PTS system gene in all the of Vibrio cholerae strains that have their genome available in the NCBI portal. Because of space only 13 strains are shown, but 42 were actually aligned, exhibiting a similar profile. A highly conserved structure is observed in the transmembrane domains (alterning pink for cytoplasmic and extracellular domains, and dark red for transmenbrane domains), as well as in the secondary structure (purple cilinder – represent alpha helix; yellow arrows – beta strands; gray coil – coils; blue curved arrows – turns), hydrophobicity, and isoelectric point (PI) (both shown as bar graphs). This profile is the same in virtually all V. cholerae strains, but is deeply altered in the truncated protein of the IEC224 strain, which has frame-shift mutation in amino-acid residue 185 (Image generated in the Geneious software [33])