Antimicrobial Resistance Studies of Plasmid-Borne and Biofilm Forming Pseudomonas species harbouring pelA, pslA and algD Surface Attachment Exopolysaccharide Genes from Water Treatment Plant.

Abstract

This study was carried out to evaluate antibiotic resistance and surface attachment exopolysaccharide genes in biofilm producing Pseudomonas species isolated from aquatic environments. 70 water samples were collected from Ezillo water treatment plant, Ebonyi State, South Eastern Nigeria. Standard techniques were used to characterize the isolates from the water samples while the antimicrobial studies were carried out in accordance to CLSI guidelines via Kirby Bauer disk diffusion method.  Biofilm formation was determined by tube binding assay using crystal violet. The presence of surface attachment genes was characterized using 16S rRNA polymerase chain reaction (PCR) analysis. Results revealed high frequency of occurrence of the isolates (81.43%) and biofilm formation (78.95%) from the water treatment plant with a statistical significant difference (P = 0.049). The biofilm isolates were completely resistant to Amoxicillin\Clavulanic acid, Tobramycin, Oxacillin and Aztreonam while showing varied resistance to Imipenem (39.46 %), Ceftaxidime (68.61 %), Ciprofloxacin (69.96 %), Ofloxacin (70.85 %), Ertapenem (84.31%) Cefepime (85.20 %), Ticarcillin (89.24 %), Amikacin (90.59 %), Gentamicin (91.93 %) and Cefotaxime (93.72 %). The multiple antibiotic resistance index (MARI) ranges between 0.64 – 0.93. Result also revealed that biofilm producing Pseudomonas species from the water treatment plant harboured surface attachment genes namely: pslA, pelA and algD.  PCR analysis showed that the identified organisms were Pseudomonas aeruginosa strain NA114 16S, Pseudomonas tolaasii strain ATCC 33618 16S, Pseudomonas mendocina strain Y20 16S, Pseudomonas aeruginosa strain F18 16S and Pseudomonas mendocina strain Y20 16S.