β-lactam-induced OMV release promotes polymyxin tolerance in sv. Typhi.

The rise of multidrug-resistant bacteria is a global concern, leading to a renewed reliance on older antibiotics like polymyxins as a last resort. Polymyxins, cationic cyclic peptides synthesized nonribosomally, feature a hydrophobic acyl tail and positively charged residues. Their antimicrobial mechanism involves initial interaction with Gram-negative bacterial outer-membrane components through polar and hydrophobic interactions.

"One for All": Functional Transfer of OMV-Mediated Polymyxin B Resistance From sv. Typhi Δ and Δ to Susceptible Bacteria.

The appearance of multi-resistant strains has contributed to reintroducing polymyxin as the last-line therapy. Although polymyxin resistance is based on bacterial envelope changes, other resistance mechanisms are being reported. Outer membrane vesicles (OMVs) are nanosized proteoliposomes secreted from the outer membrane of Gram-negative bacteria.

Structural Characterization, DFT Calculation, NCI, Scan-Rate Analysis and Antifungal Activity against of ()-2-{[(2-Aminopyridin-2-yl)imino]-methyl}-4,6-di--butylphenol (Pyridine Schiff Base).

is a ubiquitous necrotrophic filamentous fungal phytopathogen that lacks host specificity and can affect more than 1000 different plant species. In this work, we explored [(E)-2-{[(2-aminopyridin-2-yl)imino]-methyl}-4,6-di-tert-butylphenol], a pyridine Schiff base harboring an intramolecular bond (IHB), regarding their antifungal activity against Botrytis cinerea. Moreover, we present a full characterization of the L1 by NMR and powder diffraction, as well as UV-vis, in the presence of previously untested different organic solvents.

Identification of Genes Involved in Biogenesis of Outer Membrane Vesicles (OMVs) in Serovar Typhi.

Outer membrane vesicles (OMVs) are nano-sized proteoliposomes discharged from the cell envelope of Gram-negative bacteria. OMVs normally contain toxins, enzymes and other factors, and are used as vehicles in a process that has been considered a generalized, evolutionarily conserved delivery system among bacteria. Furthermore, OMVs can be used in biotechnological applications that require delivery of biomolecules, such as vaccines, remarking the importance of their study.