How Do Phages Disrupt the Structure of Biofilm?

Biofilms are composed of multicellular communities of microbial cells and their self-secreted extracellular polymeric substances (EPS). The viruses named bacteriophages can infect and lyze bacterial cells, leading to efficient biofilm eradication. The aim of this study was to analyze how bacteriophages disrupt the biofilm structure by killing bacterial cells and/or by damaging extracellular polysaccharides, proteins, and DNA.

Benefits and Challenges of the Use of Two Novel vB_Efa29212_2e and vB_Efa29212_3e Bacteriophages in Biocontrol of the Root Canal Infections.

Unlabelled: Bacteriophage therapy has emerged as a strategy supplementing traditional disinfection protocols to fight biofilms. The aim of the study was to isolate the phages against and to characterize its biological features, morphology, and lytic activity in a formed biofilm model.

Methods: ATCC 29212 strain was used for the trial.

Amikacin and bacteriophage treatment modulates outer membrane proteins composition in Proteus mirabilis biofilm.

Modification of outer membrane proteins (OMPs) is the first line of Gram-negative bacteria defence against antimicrobials. Here we point to Proteus mirabilis OMPs and their role in antibiotic and phage resistance. Protein profiles of amikacin (AMKrsv), phage (Brsv) and amikacin/phage (AMK/Brsv) resistant variants of P.

Surfactants of microbial origin as antibiofilm agents.

The microbial world provides new energy sources and many various 'green' chemicals. One type of chemicals produced by microorganisms is the biosurfactant group. Biosurfactants are universal molecules, exhibiting surface properties often accompanied by desired biological activity.

Changes in the lipopolysaccharide of Proteus mirabilis 9B-m (O11a) clinical strain in response to planktonic or biofilm type of growth.

The impact of planktonic and biofilm lifestyles of the clinical isolate Proteus mirabilis 9B-m on its lipopolysaccharide (O-polysaccharide, core region, and lipid A) was evaluated. Proteus mirabilis bacteria are able to form biofilm and lipopolysaccharide is one of the factors involved in the biofilm formation. Lipopolysaccharide was isolated from planktonic and biofilm cells of the investigated strain and analyzed by SDS-PAGE with silver staining, Western blotting and ELISA, as well as NMR and matrix-assisted laser desorption ionization time-of-flight mass spectrometry techniques.

Lipid composition in a strain of Bacillus subtilis, a producer of iturin A lipopeptides that are active against uropathogenic bacteria.

Urinary tract infections are a common disease in humans. Therefore, new methods are needed to destroy biofilms that are formed by uropathogens. Iturin A lipopeptides (LPs) C14 and C15 are potent biosurfactants synthetized by the Bacillus subtilis I'1a strain.

Antimicrobial, antiadhesive and antibiofilm potential of lipopeptides synthesised by Bacillus subtilis, on uropathogenic bacteria.

The aim of this study was to investigate the antimicrobial effect of lipopeptide biosurfactants from surfactin, iturin and fengycin families, synthesised by the Bacillus subtilis I'1a strain, on uropathogenic bacteria, including the effects on planktonic growth, processes of biofilm formation and dislodging. Antimicrobial activity was tested against 32 uropathogenic strains belonging to 12 different species of Gram-negative and Gram-positive bacteria. The sensitivity of 25 tested bacterial strains to the B.

[Extracellular matrix as a microbial virulence factor in the development of human diseases].

Extracellular polymers which build a biofilm matrix possess a complicated structure, where the polysaccharide fraction, composed of homo- or heteropolysaccharides, is the largest. Other important components are proteins, eDNA, glycoproteins and lipids. The matrix has a protective function against the surrounding environment, plays a role in biofilm formation and maturation processes, stabilizes the biofilm structure, and also is a source of nutrients and water for the cells.

Structure of the O-polysaccharide of Providencia alcalifaciens O2 containing ascarylose and N-(L-alanyl)-D-glucosamine.

The O-polysaccharide was obtained by degradation of the lipopolysaccharide of Providencia alcalifaciens O2 under mild acidic conditions followed by GPC. The polysaccharide was found to contain two unusual components: 3,6-dideoxy-L-arabino-hexose (ascarylose, Asc) and 2-(L-alanyl)amino-2-deoxy-D-glucose (GlcNAla). Ascarylose was partially split off during lipopolysaccharide degradation and could be eliminated completely by selective acid hydrolysis, which also partially cleaved the β-GAlNAc-(1 → 6) linkage.

Structure and gene cluster organization of the O-antigen of Providencia alcalifaciens O45:H25.

O-Polysaccharide was obtained by mild acid degradation of the lipopolysaccharide of Providencia alcalifaciens O45:H25 and studied by sugar analysis, Smith degradation, and (1)H and (13)C NMR spectroscopy. The following structure of the pentasaccharide repeat of the O-polysaccharide was established: [structure: see text]. The O-antigen gene cluster of P.

Structure of the O-polysaccharide from the lipopolysaccharide of Providencia alcalifaciens O33.

Mild acid degradation of the lipopolysaccharide from Providencia alcalifaciens O33 resulted in an O-polysaccharide along with core and O-unit-bearing core oligosaccharides. Composition of the oligosaccharides was inferred by ESI mass spectrometry. Based on sugar and methylation analyses, Smith degradation and (1)H and (13)C NMR spectroscopy data, the following structure of the tetrasaccharide O-unit of the O-polysaccharide was established: Another O-polysaccharide structure has been reported earlier for Providencia stuartii О33 but later found to belong to a P.

Effect of nutrient and stress factors on polysaccharides synthesis in Proteus mirabilis biofilm.

The extracellular matrix in biofilm consists of water, proteins, polysaccharides, nucleic acids and phospholipids. Synthesis of these components is influenced by many factors, e.g.

Analysis of Proteus mirabilis distribution in multi-species biofilms on urinary catheters and determination of bacteria resistance to antimicrobial agents.

The objectives of the investigation presented in this paper were: to examine the frequency of P. mirabilis isolation from catheters and assess the complexity of multi-species biofilms which these bacteria form, as well as to determine the vulnerability of planktonic and sessile P. mirabilis populations to popular antibiotics and compare it to the susceptibility of other Gram-negative bacteria isolated as associated flora from multi-species biofilm.