Phenotypic and Genotypic Investigation of Biofilm Formation in Clinical and Environmental Isolates of Acinetobacter baumannii

Abstract

Acinetobacter baumannii (A. baumannii) is an important opportunistic pathogen responsible for nosocomial infections worldwide at recent decades. Biofilm formation by A. baumannii leads to antibiotic resistance and survives on abiotic and biotic surfaces. In the present study we aimed to assess the ability of biofilm formation in clinical and environmental isolates of A. baumannii by phenotypic methods and to detect the presence of genes involving in the biofilm development; bap, ompA, csuE, abaI, and blaPER-1by PCR method. Totally 120 A. baumanniin isolates, 98 clinical, and 22 environmental were evaluated for biofilm formation using the modified Microtiter plate method, Congo red agar methods, and the existence of genes related to biofilm by standard PCR. The phenotypic results showed that the biofilm formation rate was 10.8% isolates that in environmental A. baumannii isolates were higher than clinical isolates. The abaI, csuE, and ompA genes were detected in all isolates with biofilm formation and the bap and blaPER-1genes were positive in 14.2% and 13.3% of A. baumannii isolates, respectively. The sequence of genes were submitted in NCBI. Based on our results, the Congo red agar method was significantly better than the Microtiter plate technique for phenotypic evaluation of biofilm formation in the A. baumannii. Our study indicates that abaI, csuE, and ompA genes were detected in all isolates unlike the bap and blaPER-1genes.

Molecular Study of Acinetobacter Baumannii Using 16s Rrna And Bla Oxa-51 Gene Isolated from Hospitals in Duhok-kurdistan Region, Iraq

“…baumannii to expanded-spectrum cephalosporins and carbapenems is rapidly growing over the years and limits therapeutic options, relying on polymyxins in combinations with other antibiotics (Chang et al, 2015). The survival and existence of MDR A. baumanni in environmental hospitals may be the main cause of nosocomial infections worldwide (Ghasemi et al,2018). Many researches in other countries including Iran and Turkey, have recorded a high percentage of MDR as well as XDR among A. baumannii strains (Heidari et al, 2018).…”

“…Anti-microbial sensitivity profile test of A. baumannii samples continued by the method of Diffusion Disc strategy on Mueller-Hinton agar, and a group of antimicrobs was chosen according type of Bacteria. Strategy entirely used by (Ghasemi et al, 2018).…”

Antibiotic resistance, biofilm formation, and biofilm-associated genes among Stenotrophomonas maltophilia clinical isolates

“…A prominent feature of S. maltophilia is its capability to adhere to abiotic surfaces, host tissues and biofilm formation [ 10 , 11 ]. S. maltophilia has been identified on the surfaces of biomaterials used in prosthetic devices, intravenous cannula, dental unit waterlines and nebulizers [ 12 – 14 ].…”

Molecular Identification of epsA and ompA genes for Acintobacter baumannii Isolated from Burn Wounds

“…Several virulence factors involved in bioflm formation of A. baumannii such as the outer membrane protein A (OmpA), biofilm associated protein (Bap)chaperon-usher pilus (Csu), extracellular exopolysaccharide (EPS). The OmpA of A. baumannii is essential for the attachment to human epithelial cells, development of biofilms and antimicrobial resistance (20) .…”