Molecular Characterization of Biofilm-Producing Pseudomonas aeruginosa Isolated from Healthy Pigs and Chicken in India

Abstract

Pseudomonas aeruginosa is considered as the most potent member of multidrug-resistant (MDR) and extremely resistant (XDR) gram-negative pathogens (‘ESCAPE’ group) emerged throughout the world with the property to ‘escape’ the treatment with antibiotics. Biofilm formation is a significant virulence property of P. aeruginosa generating not only antibiotic resistance, but also it acts as a constant source of infection in the host and it can prevent host defence such as chemotaxis of polynuclear immune cells. There is paucity of scientific literatures regarding characterization of biofilm producing P. aeruginosa isolated from livestock and birds. A total of 200 rectal swabs were collected from pigs (n=100) and chickens (n=100) from Mizoram state of India. All the specimens were processed of isolation and identification of P. aeruginosa, which were further confirmed by 16S rRNA PCR and Phoenix bacterial identification system. All the isolates were subjected to detection of biofilm producing ability by microtiter plate assay, antimicrobial sensitivity by disc diffusion assay and detection of selected biofilm producing genes as well as selected beta lactamase genes by specific PCR assay. A total of 11 P. aeruginosa were isolated from pigs (n=6) and chickens (n=5). All the isolates were recorded as positive for biofilm production by microtiter plate assay and were positive for at least one biofilm associated genes. A total of 8 isolates were positive for blaTEM gene and one isolates was positive for blaCTX-M gene. This is probably the unique report on isolation of P. aeruginosa from animals carrying both beta lactamase as well as biofilm producing genes.