Evaluation of Azido 3-Deoxy-d--oct-2-ulosonic Acid (Kdo) Analogues for Click Chemistry-Mediated Metabolic Labeling of DZ2 Lipopolysaccharide.

Metabolic labeling paired with click chemistry is a powerful approach for selectively imaging the surfaces of diverse bacteria. Herein, we explored the feasibility of labeling the lipopolysaccharide (LPS) of -a Gram-negative predatory social bacterium known to display complex outer membrane (OM) dynamics-via growth in the presence of distinct azido (-N) analogues of 3-deoxy-d--oct-2-ulosonic acid (Kdo). Determination of the LPS carbohydrate structure from strain DZ2 revealed the presence of one Kdo sugar in the core oligosaccharide, modified with phosphoethanolamine.

Total Synthesis of 6-Amino-2,6-dideoxy-α-Kdo from d-Mannose.

3-Deoxy-d--oct-2-ulosonic acid (Kdo) biosynthetic pathway is a promising target in antibacterial drug discovery. Herein, we report the total synthesis of 6-amino-2,6-dideoxy-α-Kdo in 15 steps from d-mannose as a potential inhibitor of Kdo-processing enzymes. Key steps of the synthetic sequence involve a Horner-Wadsworth-Emmons reaction for the two-carbon chain homologation followed by either a 6- Pd-catalyzed reductive cyclization or a tandem Staudinger/aza-Wittig reaction with concomitant α-iminoester reduction, enabling the α-stereoselective formation of the Kdo-like six-membered azacyclic ring.

Modulation of bacterial multicellularity via spatio-specific polysaccharide secretion.

The development of multicellularity is a key evolutionary transition allowing for differentiation of physiological functions across a cell population that confers survival benefits; among unicellular bacteria, this can lead to complex developmental behaviors and the formation of higher-order community structures. Herein, we demonstrate that in the social δ-proteobacterium Myxococcus xanthus, the secretion of a novel biosurfactant polysaccharide (BPS) is spatially modulated within communities, mediating swarm migration as well as the formation of multicellular swarm biofilms and fruiting bodies. BPS is a type IV pilus (T4P)-inhibited acidic polymer built of randomly acetylated β-linked tetrasaccharide repeats.

Polysaccharides from Burkholderia species as targets for vaccine development, immunomodulation and chemical synthesis.

Covering: up to 2018 Burkholderia species are a vast group of human pathogenic, phytopathogenic, and plant- or environment-associated bacteria. B. pseudomallei, B.