Bacterial biofilm and associated infections

Abstract

Microscopic entities, microorganisms that drastically affect human health need to be thoroughly investigated. A biofilm is an architectural colony of microorganisms, within a matrix of extracellular polymeric substance that they produce. Biofilm contains microbial cells adherent to one-another and to a static surface (living or non-living). Bacterial biofilms are usually pathogenic in nature and can cause nosocomial infections. The National Institutes of Health (NIH) revealed that among all microbial and chronic infections, 65% and 80%, respectively, are associated with biofilm formation. The process of biofilm formation consists of many steps, starting with attachment to a living or non-living surface that will lead to formation of micro-colony, giving rise to three-dimensional structures and ending up, after maturation, with detachment. During formation of biofilm several species of bacteria communicate with one another, employing quorum sensing. In general, bacterial biofilms show resistance against human immune system, as well as against antibiotics. Health related concerns speak loud due to the biofilm potential to cause diseases, utilizing both device-related and non-device-related infections. In summary, the understanding of bacterial biofilm is important to manage and/or to eradicate biofilm-related diseases. The current review is, therefore, an effort to encompass the current concepts in biofilm formation and its implications in human health and disease.

Biofilm production by pathogens associated with canine otitis externa, and the antibiofilm activity of ionophores and antimicrobial adjuvants

“…Biofilms are initially formed when monolayers of planktonic bacteria attach irreversibly to a living or nonliving surface, followed by production of a three-dimensional extracellular matrix consisting mainly of exopolysaccharides (EPS). Maturation of the biofilm is followed by dispersion of bacteria, allowing further spread of infection (Jamal et al, 2018;Kostakioti, Hadjifrangiskou, & Hultgren, 2013). Biofilm forming ability is, therefore, considered as a virulence factor contributing to antibiotic resistance and the spread of nosocomial infections (Osland, Vestby, Fanuelsen, Slettemeås, & Sunde, 2012).…”

Evaluating the antibacterial and antibiofilm potential of sulphated polysaccharides extracted from green algaeChlamydomonas reinhardtii

“…They crosslink together and make protective layer in which bacteria lives with slow metabolic rate (Mann et al ; Alhede et al ; Yan et al . ; Jamal et al ). This protective barrier of biofilms offer strong resistance against antibiotics, host immune response, degrading enzymes etc (Stewart and Costerton ; Shahwany et al ).…”

“…Biofilms are mainly composed of~96-97% of water and extra polymeric substances (~3-4%) (EPS layer) which includes polysaccharides, proteins and nucleic acids (DNA and RNA). They crosslink together and make protective layer in which bacteria lives with slow metabolic rate (Mann et al 2009;Alhede et al 2011;Yan et al 2016;Jamal et al 2018). This protective barrier of biofilms offer strong resistance against antibiotics, host immune response, degrading enzymes etc (Stewart and Costerton 2001;Shahwany et al 2016).…”

BeQuIK (Biosensor Engineered Quorum Induced Killing): designer bacteria for destroying recalcitrant biofilms

“…The biofilm matures into a three‐dimensional structure that is difficult to penetrate or degrade in a process governed by bacterial quorum sensing (QS) via signalling molecules in accordance with population density (Miller and Bassler, ). Ultimately, the cell cluster is dispersed to release planktonic cells back into the environment to continue the cycle (Jamal et al ., ).…”