Distinct structural Omp33-36 porins among the Acinetobacter spp. population.
(A) Shannon variability of Omp33-36 sequences within groups I, II and III. The height of each bar indicates the entropy of an amino acid residue at a given position. The conserved (C1-C6) regions and variable (V1-V6) regions are shown. (B) Predicted transmembrane topology of the different A. baumannii Omp33-36 variants (1–4) representing Omp33-36- groups. External loops (L1-L7), transmembrane spanning regions (β1-β14) and periplasmic regions are depicted.