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Intracellular fucoidanase was isolated from the marine bacterium, Formosa algae strain KMM 3553. The first appearance of fucoidan enzymatic hydrolysis products in a cell-free extract was detected after 4 h of bacterial growth, and maximal fucoidanase activity was observed after 12 h of growth. The fucoidanase displayed maximal activity in a wide range of pH values, from 6.5 to 9.1. The presence of Mg2+, Ca2+ and Ba2+ cations strongly activated the enzyme; however, Cu2+ and Zn2+ cations had inhibitory effects on the enzymatic activity. The enzymatic activity of fucoidanase was considerably reduced after prolonged (about 60 min) incubation of the enzyme solution at 45 °C. The fucoidanase catalyzed the hydrolysis of fucoidans from Fucus evanescens and Fucus vesiculosus, but not from Saccharina cichorioides. The fucoidanase also did not hydrolyze carrageenan. Desulfated fucoidan from F. evanescens was hydrolysed very weakly in contrast to deacetylated fucoidan, which was hydrolysed more actively compared to the native fucoidan from F. evanescens. Analysis of the structure of the enzymatic products showed that the marine bacteria, F. algae, synthesized an α-L-fucanase with an endo-type action that is specific for 1→4-bonds in a polysaccharide molecule built up of alternating three- and four-linked α-L-fucopyranose residues sulfated mainly at position 2. [ABSTRACT FROM AUTHOR]

The chemical structure of a novel lipid A, the major component of the lipopolysaccharide from the marine gamma-proteobacterium Marinomonas vaga ATCC 27119T, was determined by compositional analysis, NMR spectroscopy, and MS. It was found to be β-1,6-glucosaminobiose 1-phosphate acylated with ( R)-3-[dodecanoyl(dodecenoyl)oxy]decanoic acid {C10 : 0 (3O-C12 : 0 [3O-C12 : 1])} or ( R)-3-(decanoyloxy)decanoic acid [C10 : 0 (3O-C10 : 0)], ( R)-3-hydroxydecanoic acid [C10 : 0 (3OH)], and ( R)-3-[( R)-3-hydroxydecanoyloxy]decanoic acid (C10 : 0 {3O-[C10 : 0 (3OH)]}) at the 2, 3, and 2′ positions, respectively. It showed low lethal toxicity, which is probably related to specific structural attributes. The absence of a fatty acid at the 3′ position and a phosphoryl group at the 4′ position and also the presence of an amide-linked ( R)-3-hydroxyalkanoic acid that is further O-acylated with another ( R)-3-hydroxyalkanoic acid, distinguish M. vaga lipid A from other such molecules. [ABSTRACT FROM AUTHOR]

Lipopolysaccharides of Yersinia enterocolitica serovars O;5 and O;5,27 were shown to have a similar sugar composition, consisting of L-rhamnose, D-glucose, D-galactose, D- and L-glycero-D-manno--heptose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose, 3-deoxy-D-manno-octulosonate and D-threo-pent-2-ulose (D-xylulose). Partial hydrolysis of lipopolysaccharides with acetic acid produced rhamnans with the following repeating unit: → 3)-L-Rhap(α1 → 3)-L-Rhap(α1 → 3)-L-Rhap(β1 →. 13C-NMR and methylation studies of the lipopolysaccharides gave the following structure for the repeating unit of the two O-specific polysaccharides: … [ABSTRACT FROM AUTHOR]

Lipopolysaccharides from Yersinia enterocolitica serovars O:1,2a,3, O:2a,2b,3 and O:3 have been isolated and characterized. 6-Deoxy-L-altrose residues were shown to be the main constituents of lipopolysaccharidcs isolated in addition to residues of L-rhamnose, D-glucose, D-galactose, 2-acetamido-2-deoxy-D-glucose, 2-acetamido-2-deoxy-D-galactose, D-glycero-D-manno-heptose and L-glycero-D-manno-heptose, 3-deoxy-D-manno-octulosonic acid being minor components of sugar chains. Mild hydrolysis of lipopolysaccharides with acetic acid furnished O-specific polysaccharides, which are composed of 6-deoxy-L-altrose. Using 13C-NMR spectroscopy and methylation data, the structural features of backbones have been elucidated as follows: →2)-6d-L-Altp(β1 →2)-6d-L-Altp(β1 → 3)-6d-L-Altp)(β1 → for serovars O:1.2a,3 and O:2a,2b,3: → 2)-6d-L-Altp(β1 → for serovar O:3. In addition, O-polysaccharide of serovar O:2a,2b,3 was found to contain an O-acetyl group at the C-3 position of some 1,2-linked sugar residues. [ABSTRACT FROM AUTHOR]

The use of 13C-NMR spectroscopy in the establishment of lipid A backbone structure from lipopolysaccharide of Yersinia pseudotuberculosis has been described. The 13C-NMR spectra of degraded lipid A and its N-acetate were obtained. The assignment of signals was made by comparison with the chemical shifts for 13C-NMR spectra of glucosaminitol, N-acetyl-glucosaminitol and their β-1.4 and β-1.6 disaccharides. It was shown that lipid A backbone of the lipopolysaccharide in question consists of β.-1.6-linked glucosamine disaccharide [ABSTRACT FROM AUTHOR]

Abstract: The O-specific polysaccharide was isolated from the lipopolysaccharide of a marine bacterium Oceanisphaera litoralis KMM 3654T and studied by chemical methods along with 1H and 13C NMR spectroscopy. The following new structure of the O-specific polysaccharide of O. litoralis containing d-glucose and two residues of 2-acetamido-2-deoxy-d-mannuronic acid was established: Display Omitted [Copyright &y& Elsevier]

The chemical structure of a novel lipid A, the major component of the lipopolysaccharide from the marine gamma-proteobacterium Marinomonas vaga ATCC 27119T, was determined by compositional analysis, NMR spectroscopy, and MS. It was found to be β-1,6-glucosaminobiose 1-phosphate acylated with ( R)-3-[dodecanoyl(dodecenoyl)oxy]decanoic acid {C10 : 0 (3O-C12 : 0 [3O-C12 : 1])} or ( R)-3-(decanoyloxy)decanoic acid [C10 : 0 (3O-C10 : 0)], ( R)-3-hydroxydecanoic acid [C10 : 0 (3OH)], and ( R)-3-[( R)-3-hydroxydecanoyloxy]decanoic acid (C10 : 0 {3O-[C10 : 0 (3OH)]}) at the 2, 3, and 2′ positions, respectively. It showed low lethal toxicity, which is probably related to specific structural attributes. The absence of a fatty acid at the 3′ position and a phosphoryl group at the 4′ position and also the presence of an amide-linked ( R)-3-hydroxyalkanoic acid that is further O-acylated with another ( R)-3-hydroxyalkanoic acid, distinguish M. vaga lipid A from other such molecules. [ABSTRACT FROM AUTHOR]

Abstract: Spectral-luminescence properties of several dimethylaminostyryl-β-diketonates of boron difluoride with different α-substituents have been investigated through stationary and time-resolved spectroscopy. Quantum chemistry studies of the structure of excited states of 2,2-difluoro-4-(4′-dimethylaminostyryl)-6-phenyl-1,3,2-dioxaborine have been performed. Two luminescence centers have been revealed for the compound under study: an intensive band in the red–orange region of the spectrum caused by an S1–S0 transition and a short-wave luminescence in the blue region of the spectrum caused by an S2–S0 transition. [Copyright &y& Elsevier]

Abstract: The contents and structural characteristics of water-soluble polysaccharides such as polyuronans, fucoidans and laminarans dependent on species, age of algae and the year of collection were studied for four species of brown algae—Alaria fistulosa, A. marginata, Fucus evanescens and Laminaria cichorioides, widespread on the Russian Far-East. The mature L. cichorioides was shown to be the richest source of both laminarans and fucoidans, F. evanescens—fucoidans. However, the Alaria species and young age algae F. evanescens contained practically polyuronans only. Alaria marginata and A. fistulosa were revealed to have a little of fucoidan and negligible quantity of laminaran (less than 1%). Contents of water-soluble polyuronans in A. fistulosa were approximately 2 times more, than in A. marginata. Water-soluble polyuronans of these seaweeds are represented by polymannuronans (Mm about 40 kDa). It was shown, that the young age algae F. evanescens contains the water-soluble low-molecular mass mannuronans along with the high-molecular mass laminarans. Stimulating action of polyuronans on the sea urchin developing embryos was revealed. [Copyright &y& Elsevier]