Polysaccharides’ Structures and Functions in Biofilm Architecture of Antimicrobial-Resistant (AMR) Pathogens

Abstract

Bacteria and fungi have developed resistance to the existing therapies such as antibiotics and antifungal drugs, and multiple mechanisms are mediating this resistance. Among these, the formation of an extracellular matrix embedding different bacterial cells, called biofilm, is an effective strategy through which bacterial and fungal cells are establishing a relationship in a unique environment. The biofilm provides them the possibility to transfer genes conferring resistance, to prevent them from desiccation and to impede the penetration of antibiotics or antifungal drugs. Biofilms are formed of several constituents including extracellular DNA, proteins and polysaccharides. Depending on the bacteria, different polysaccharides form the biofilm matrix in different microorganisms, some of them involved in the first stage of cells’ attachment to surfaces and to each other, and some responsible for giving the biofilm structure resistance and stability. In this review, we describe the structure and the role of different polysaccharides in bacterial and fungal biofilms, we revise the analytical methods to characterize them quantitatively and qualitatively and finally we provide an overview of potential new antimicrobial therapies able to inhibit biofilm formation by targeting exopolysaccharides.

Customized Lanthanide Nanobiohybrids for Noninvasive Precise Phototheranostics of Pulmonary Biofilm Infection

“…We also investigated the antibacterial effect of NaNdF 4 @DMS-Aly on the Staphylococcus aureus (S. aureus) biofilm, in which teichoic acids instead of alginate were the dominant exopolysaccharides . There was no significant difference in the viability of S.…”

“…We also investigated the antibacterial effect of NaNdF 4 @DMS-Aly on the Staphylococcus aureus (S. aureus) biofilm, in which teichoic acids instead of alginate were the dominant exopolysacchar-ides. 48 There was no significant difference in the viability of S. aureus between agents with and without Aly (1.5 log 10 for both cases, Figure S16). Based on these results, it can be deduced that the synergistic effect of Aly and PTT was responsible for the significant efficacy of NaNdF 4 @DMS-Aly against the P. aeruginosa biofilm.…”

Advances in Nanotechnology for Biofilm Inhibition

“…The presence of EPS has been shown to weaken the efficacy of antibiotics by restricting their capability to infiltrate the biofilm matrix. − Additionally, EPS provide a shielding barrier for cells residing within the microbial biofilm. To destabilize biofilms, antimicrobial compounds must permeate the surface of the biofilm.…”

Вплив похідного адамантану на експресію генів плівкоутворення P. Aeruginosa

“…На наступному етапі плівкоутворення -формування мікроколоній і моношару, експресія генів оперону Рис. 3…”

“…Важливу роль в адгезії та формуванні біоплівок у немукоїдних штамів P. aeruginosa відіграють полісахариди Рsl і Рel, у мукоїдних штамівальгінат [3][4][5]. Полісахарид Psl складається з пентамера, що містить d-маннозу, l-рамнозу та d-глюкозу, утворюючи тканиноподібний матрикс, який з'єднує клітини біоплівки.…”