Acinetobacter baumannii biofilm and its potential therapeutic targets

Abstract

Acinetobacter baumannii (A. baumannii) is an opportunistic pathogen that poses dangerous health threat. It is a main cause of biofilm-associated infections that are mostly resistant to antibiotic therapy. Because of its capacity to form biofilm on biotic and abiotic surfaces, it has been linked to most nosocomial infections such as ventilator-associated pneumonia, urinary tract infections, bacteremia, meningitis, wound infections, soft tissue infections, and peritonitis. The biofilm refers to an organized group of microbial cells that are embedded in an exopolymeric substance made of protein, extracellular DNA, and polysaccharide. Bacterial cells in biofilms are resistant to chemicals, phagocytosis, and other elements of the body’s innate and acquired immune systems posing treatment challenges. Biofilm formation in A. baumannii is a complicated process that is influenced by a variety of factors such as outer membrane protein A, poly-β-(1,6)-N acetyl glucosamine (PAGE), biofilm-associated protein, two-component system (Bfm/S BfmR), chaperone–usher (Csu) pilus assembly system of pili, BlaPER-1 belonging to β-lactamase family, extracellular polymeric substance, and the quorum sensing system. Several biofilm-associated genes influence antimicrobial susceptibility, implying a link between biofilm formation and antimicrobial resistance. This review describes the complex biofilm system of A. baumannii, which gives it a survival advantage and increases its colonization ability. Also, it demonstrates various extrinsic and intrinsic factors that function and regulate the biofilm machinery of A. baumannii. Furthermore, this study considers prospective ways for preventing biofilm development on relevant medical equipment, as well as potential therapeutic strategies for eradicating mature biofilms, which can aid in the treatment of biofilm-associated A. baumannii infection.