Bacterial biofilms: from the Natural environment to infectious diseases

Abstract

Biofilms--matrix-enclosed microbial accretions that adhere to biological or non-biological surfaces--represent a significant and incompletely understood mode of growth for bacteria. Biofilm formation appears early in the fossil record (approximately 3.25 billion years ago) and is common throughout a diverse range of organisms in both the Archaea and Bacteria lineages, including the 'living fossils' in the most deeply dividing branches of the phylogenetic tree. It is evident that biofilm formation is an ancient and integral component of the prokaryotic life cycle, and is a key factor for survival in diverse environments. Recent advances show that biofilms are structurally complex, dynamic systems with attributes of both primordial multicellular organisms and multifaceted ecosystems. Biofilm formation represents a protected mode of growth that allows cells to survive in hostile environments and also disperse to colonize new niches. The implications of these survival and propagative mechanisms in the context of both the natural environment and infectious diseases are discussed in this review.

Environmental adaptation and vertical dissemination of ESBL‐/pAmpC‐producing Escherichia coli in an integrated broiler production chain in the absence of an antibiotic treatment

“…The ability to form bacterial biofilms is a benefit in the survival against host defence factors, antibiotics, physical and chemical stress as well as disinfectants (Hall‐Stoodley et al ., 2004; Flemming and Wingender, 2010). Using a macrocolony assay, we could show that more than half of our tested strains from both investigated sets were able to produce curli fibres and the exopolysaccharide cellulose which are necessary to form stable and strong biofilm matrices (Olsen et al ., 1989; Barnhart and Chapman, 2006; Uhlich et al ., 2006; Serra et al ., 2013, 2015).…”

Bacterial adhesion to suture material in a contaminated wound model: Comparison of monofilament, braided, and barbed sutures

“…8 This situation is aggravated further by biofilm formation, 9 in which bacteria that are attached to a surface encapsulate themselves within a self-secreted extracellular polymeric slime matrix composed of polysaccharides, proteins, and nucleic acids. 10 In more than 60% of clinical infections, bacteria protect themselves by hiding in such a biofilm. 11 Within a biofilm, even ABX-sensitive strains of bacteria can become highly tolerant to such treatment.…”

“…around Vicryl was reduced by a factor of 1.5, from 12 mm (11-16) to 8 mm (5)(6)(7)(8)(9)(10)(11)(12)(13)(14). With E. coli and E. faecium, but also with S. aureus, even under a long and high concentration treatment, bacterial presence on the sutures could only be partly reduced.…”

Suspecting non-cystic fibrosis bronchiectasis: What the busy primary care clinician needs to know

“…Some microorganisms, such as Pseudomonas aeruginosa , may form biofilms in the bronchial airways. Biofilms are thin layers that form on colonised surfaces typically comprised of bacteria and a matrix of an extracellular polymeric substance that includes polysaccharides, proteins and DNA 16. This may facilitate the persistence of the “vicious cycle” of bronchiectasis because the biofilms protect bacteria from clearance by the host immune system and reduce the effects of antibiotics further potentiating airway inflammation 17.…”