Investigation of biofilm formation ability and Assessment of cupB and rhlR Gene Expression in Clinical Isolates of Pseudomonas aeruginosa

Abstract

Pseudomonas aeruginosa forms structured communities known as biofilms, are normally associated with the transition from an acute to a chronic infection, making the biofilm one of the bacteria's most effective virulence factors. This study was designed to investigate the biofilm formation ability to the identified clinical isolates using microtiter plate assay, and assess the gene expression of the biofilm related genes cupB and rhlR by employing the RT-qPCR. 102 samples was collected from clinical sources and after the identification 21 clinical isolates were confirmed to be Pseudomonas aeruginosa forming (20.5%) of the total sample size. The biofilm formation assay revealed that 18 out of the tested 21 isolated were biofilm producer 10 (47.6%), 5 (23.8%), 3 (14.2%) were strong, moderate and weak respectively, while 3(14.2%) were non-biofilm forming isolates. The folding levels for cupB was presenting an over-expression in all biofilm forming groups as well as the non-biofilm forming group, as for the rhlR expression it was found to be over-expressing in both strong and moderate biofilm forming group, while it showed low-expression in weak and non-biofilm forming groups. According to this data the cupB gene expression was found to be more directly connected to the intensity of the biofilm formed by the isolates compared to rhlR.