Antibiofilm and Anti-Infection of a Marine Bacterial Exopolysaccharide Against Pseudomonas aeruginosa

Abstract

Pseudomonas aeruginosa is a well-known pathogenic bacterium that forms biofilms and produces virulence factors, thus leading to major problems in many fields, such as clinical infection, food contamination, and marine biofouling. In this study, we report the purification and characterization of an exopolysaccharide EPS273 from the culture supernatant of marine bacterium P. stutzeri 273. The exopolysaccharide EPS273 not only effectively inhibits biofilm formation but also disperses preformed biofilm of P. aeruginosa PAO1. High performance liquid chromatography traces of the hydrolyzed polysaccharides shows that EPS273 primarily consists of glucosamine, rhamnose, glucose and mannose. Further investigation demonstrates that EPS273 reduces the production of the virulence factors pyocyanin, exoprotease, and rhamnolipid, and the virulence of P. aeruginosa PAO1 to human lung cells A549 and zebrafish embryos is also obviously attenuated by EPS273. In addition, EPS273 also greatly reduces the production of hydrogen peroxide (H2O2) and extracellular DNA (eDNA), which are important factors for biofilm formation. Furthermore, EPS273 exhibits strong antioxidant potential by quenching hydroxyl and superoxide anion radicals. Notably, the antibiofouling activity of EPS273 is observed in the marine environment up to 2 weeks according to the amounts of bacteria and diatoms in the glass slides submerged in the ocean. Taken together, the properties of EPS273 indicate that it has a promising prospect in combating bacterial biofilm-associated infection, food-processing contamination and marine biofouling.

Genomic and Transcriptomic Insights into Calcium Carbonate Biomineralization by Marine Actinobacterium Brevibacterium linens BS258

“…The CaCO 3 -producing medium was prepared as following: nutrient broth (3 g), NaHCO 3 (2.12 g), NH 4 Cl (10 g), CaCl 2 (16.65 g), urea (20 g) and agar (15 g) in one liter filtered seawater. Genomic DNA was extracted from the isolate, and PCR (polymerase chain reaction) was performed to amplify the 16S rDNA gene sequence as described previously with universal primers 27F (5′-AGAGTTTGATCCTGGCTCAG-3′) and 1492R (5′-AAGGAGGTGATCCACCC-3′) (Wu et al, 2016). To determine the phylogenetic position of the B. linens BS258, the 16S rDNA gene sequence was analyzed by the BLAST programs 1 .…”

A novel exopolysaccharide produced by Lactobacillus coryniformis NA-3 exhibits antioxidant and biofilm-inhibiting properties in vitro

“…Hydroxyl radical-scavenging activity The hydroxyl radical-scavenging activity of EPS was determined according to the method described by Wu et al (31), with few modifications. In brief, PBS (20 mM, pH 7.4), 50 μL; 12.5-mM 1,10-phenanthroline solution, 25 μL; 2.5-mM FeSO 4 solution, 25 μL; and 20-mM H 2 O 2 , 25 μL were added successively to each well of 96-well plates and mixed thoroughly.…”

“…Given its capacity for antioxidant activity, we next decided to test whether EPS-NA3 also exhibited the ability to inhibit biofilm formation (31), given the role of EPS in preventing colonization by competing bacteria. Observation by fluorescence microscopy of B. cereus (Figs.…”

Inflammatory potential of monospecies biofilm matrix components

“…Allesen-Holm et al (2006) reported that P. aeruginosa biofilm produces a large amount of eDNA in the late-log phase (4-10 h) of growth. Thus, eDNA could represent a key target for anti-biofilm strategies, by disabling biofilm establishment or disrupting the structure at early stages (Martins et al 2010, Wu et al 2016. Macrophages are the primary innate immune cell that participate in chronic periapical lesions (Nair 2004).…”