Fig. 2

Evolutionary relationships of the A. baumannii strains based on 16SrRNA sequences. The evolutionary history was inferred using the Neighbor joining method. 1000 bootstrap re-samplings were done to estimate the consensus tree. The optimal tree with a sum of branch length = 0.5833 is shown. The tree is drawn to scale with branch lengths in same units as those of evolutionary distances used to infer the phylogenetic tree. The evolutionary distances were computed using the maximum composite likelihood method and are in the units of the number of base substitutions per site. a Illustrates the complete phylogenetic tree of all the included strains and b shows the enhanced view of the selected clads. The strains like A. baumannii AYE, A. baumannii A1, A. baumannii 307-0294 all belonging to IC I fall in the same clade, indicating phylogenetically closeness to their clonal strains. A. baumannii D1279779 expressed as a separate branch of the tree, validating the unique properties of this strain in between IC I and IC II. Similarly strains belonging to IC II appeared in single clad, showing their close phylogenetic relationships