PIGMENTATION ANALYSIS REVEALS PYOCYANIN AS THE PREDOMINANT PIGMENT PRODUCED BY Pseudomonas aeruginosa COLONIZING WOUNDS/ULCERS

Abstract

Pigment production is an important factor in the pathogenesis of Pseudomonas spp infection and could affect its prognosis. In addition to aiding a pathogen to evade the immune system and resist the antagonistic effect of antimicrobial drugs, pigments can induce tissue necrosis in infected wounds and disrupt the wound healing process. In this study, the infection of wounds/ulcers by Pseudomonas spp. and characterization of the type of pigment produced by isolates were analysed. Four hundred and twenty (420) wound swab samples were collected via the Levine technique, from patients attending various health centers in Maiduguri, Borno State, Nigeria. Samples were processed using standard microbiological procedure for the identification of Pseudomonas spp and suspect colonies were further confirmed using biochemical tests. Pigmentation was examined by the growth of Pseudomonas spp on Cetrimide agar. Seventy-two (72) samples yielded the growth of Pseudomonas spp, which gives a bacterial recovery rate of 17.1%. Three Pseudomonas spp were identified: P. aeruginosa (94.4%), P. putida (2.8%) and P. fluorescens (2.8%). Majority of Pseudomonas spp identified were Pyocyanin pigment producers (93.0%) followed by Pyoverdine (5.6%) and Pyomelanin (1.4%). Pigmentation across the three species revealed that 94.4% of P. aeruginosa were Pyocyanin producers and only one isolate produced Pyomelanin. All P. putida and P. fluorescens identified were Pyoverdine producers (p<0.01). Thus, analyzing pigment production in clinical isolates of Pseudomonas spp. can be an important tool that can provide an insight to their virulence status, and the disruption of pathways for the synthesis of these pigments can improve the prognosis of infections caused by Pseudomonas spp.

Keywords: Wound infection; Pseudomonas spp; Pigment; P. aeruginosa; Pyocyanin

https://doi.org/ 10.5281/zenodo.10579921