Microbial Biofilms: Structural Plasticity and Emerging Properties

Abstract

Microbial biofilms are found everywhere and can be either beneficial or detrimental, as they are involved in crucial ecological processes and in severe chronic infections. The functional properties of biofilms are closely related to their three-dimensional (3D) structure, and the ability of microorganisms to collectively and dynamically shape the community spatial organization in response to stresses in such biological edifices. A large number of works have shown a relationship between the modulation of the spatial organization and ecological interactions in biofilms in response to environmental fluctuations, as well as their emerging properties essential for nutrient cycling and bioremediation processes in natural environments. On the contrary, numerous studies have emphasized the role of structural rearrangements and matrix production in the increased tolerance of bacteria in biofilms toward antimicrobials. In these last few years, the development of innovative approaches, relying on recent technological advances in imaging, computing capacity, and other analytical tools, has led to the production of original data that have improved our understanding of this close relationship. However, it has also highlighted the need to delve deeper into the study of cell behavior in such complex communities during 3D structure development and maturation— from a single-cell to a multicellular scale— to better control or harness positive and negative impacts of biofilms. For this Special Issue, the interplay between biofilm emerging properties and their 3D spatial organization considering different models, from single bacteria to complex environmental communities, and various environments, from natural ecosystems to industrial and medical settings are addressed.

Supramolecular Self-Associating Amphiphiles Inhibit Biofilm Formation by the Critical Pathogens, Pseudomonas aeruginosa and Candida albicans

“…The complex tertiary composition of a biofilm extracellular matrix (EXM) avails various antimicrobial defense mechanisms through physical, electrostatic, and microenvironment considerations. − These formidable resistance and defense mechanisms are employed at the attachment phase of biofilm formation and increase as the biofilm matures . In line with this, when the application of SSAs against preformed biofilms is considered, a decrease in antibiofilm activity is expected.…”

The Gut Microbiota and Inflammatory Factors in Pediatric Appendicitis

“…Another defense mechanism is the thick and firm mucin layer, which is insoluble to prevent pathogens from damaging intestinal epithelial cells [ 28 ]. Furthermore, biofilms were shed actively at regular intervals so that bacteria was left from their surface, facilitating the exclusion of pathogens and the recolonization of beneficial bacteria [ 27 , 29 ]. However, there is no shedding process in the appendix, which might serve as an area for normal gut microflora and help repopulate normal microbial balance after diarrhea [ 4 , 30 , 31 ].…”

Bio-Environmental preparation of Selenium Nanoparticle using Klebsiella Pneumonia and their Biomedical Activity

“…02 percent acridine orange solution is used to stain biofilm samples properly. [5] Figure 9. Fluorescence microscope Analysis of bacterial biofilm by selenium nanoparticles.…”