Exopolysaccharides produced by Burkholderia cenocepacia recA lineages IIIA and IIIB

Abstract

Clinical and environmental strains of Burkholderia cenocepacia belonging to the recA lineages IIIA and IIIB were examined for exopolysaccharide (EPS) production. The exopolysaccharides structure was determined using mainly gas chromatography coupled to mass spectrometry and NMR spectroscopy. All the strains produced Cepacian, a highly branched polysaccharide constituted of a heptasaccharide repeating unit, composed of one rhamnose, one glucose, one glucuronic acid, one mannose and three galactose residues. This polymer is the most common exopolysaccharide produced by strains of the Burkholderia cepacia (Bcc) complex. One clinical strain produced also another polysaccharide constituted of three galactose units and one 3-deoxy-D-manno-2-octulosonic acid residues, a polymer that was previously isolated from two strains of B. cepacia genomovar I and B. cenocepacia IIIA.

Purine Biosynthesis, Biofilm Formation, and Persistence of an Insect-Microbe Gut Symbiosis

“…Second, we directly measured the weight of the exopolysaccharide produced by the wild-type and mutant Burkholderia strains. Because mannitol medium has been reported to induce the production of exopolysaccharide in Burkholderia cenocepacia (20), we cultured the strains in mannitol medium for 3 days and purified exopolysaccharide from the culturing media. The ⌬purT mutant strain produced significantly less exopolysaccharide than the wild-type and the ⌬purN mutant strains (Fig.…”

“…Bacterial exopolysaccharide was purified from cell culture media by following a previously described method with modifications (20). Bacterial cells were grown for 3 days at 30°C in 10 ml of mannitol medium (0.2% yeast extract and 2% mannitol) containing rifampin.…”

Preliminary studies on the chemical characterization and antioxidant properties of acidic polysaccharides from Sargassum fusiforme

“…The ring proton regions δ 3.0~4.2 showed overlapping peaks and were assigned to protons of carbons C2 to C5 (or C6) of the glycosidic ring. And the high field region δ 1.28, observed as two well-separated signals, contributed to the methyl groups of two kinds of glycosyl linkages of rhamnose residues (Chiarini et al, 2004;Cozzolino et al, 2006). Likewise, in their 13 C NMR spectra, a low-field intense signal at δ 175 corresponded to −CO 2 H of uronic acids (Simas et al, 2006).…”

Graded Ethanol Fractionation and Structural Characterization of Alkali-Extractable Hemicelluloses from Olea europaea L.

“…The hemicellulose subfraction H30 exhibited anomeric protons at 4.31, 4.50, and 5.16 ppm, which are assigned to nonsubstituted backbone of D-xylp units, 4-O-methyl-D-GlcpA attached via α-(1→2) linkage to xylose, and 4-O-methyl-D-GlcpA residues, respectively (Lisboa et al 2005). The relevant signals at 4.90 to 5.60 ppm are assigned to α-anomeric protons, and 4.30 to 4.90 ppm to β-anomers (Chiarini et al 2004). This confirmed that the xylose unit is linked β-glycosidically, which was in agreement with the presence of a small sharp peak at 899 cm -1 in the FT-IR spectra.…”