Phylogenetic analysis on 16S rRNA of Pseudomonas Species isolated from clinical specimens in Nigeria and other Regions

Abstract

This project was to study the clinical isolates of Pseudomonas organisms in Nigeria in comparison with those of other regions of the world, to understand their evolutional relationship, using phylogenetic analysis of 16SrRNA. A total of 51 sequence data files of Pseudomonas species from different countries were selected based on 16S rRNA, using the National Centre for Biotechnology Information (NCBI) webpage. Geneious software (V9.0.5) was employed for sequence alignment. Tamura- Nei was used as the genetic distant model, while the tree build method was Neighbor-Joining with a bootstrap value of 1000 and 100 numbers of replicates to indicate the revolutionary process analyzed over time. Majority of the strains from Nigeria (7) have very little or no mutations in the sequences. These strains with other strains from the other countries were clustered at the 2nd branch of the tree, with a bootstrap value of 96%. Generally, there is similarity in diversity of the Pseudomonas species across the globe. Much diversity was seen in all the strains from Saudi Arabia, as all were found on the 10th branch of the tree. Two Pseudomonas strains previously identified as belonging to other species than aeruginosa were seen to be Pseudomonas aeruginosa strains. The low diversity shown by the strain isolates from Nigeria implies high fidelity to genetic stability with regard to the ancestral origin. The high mutation observed in all the strains from Saudi-Arabia indicates high diversity from the common ancestor and this may likely result to increased virulence and multi-drug resistance.