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The structure of an acidic O-specific polysaccharide from the marine bacterium Cellulophaga baltica was established by chemical methods of analysis and NMR spectroscopy. The polysaccharide was shown to consist of repeating tetrasaccharide units containing two mannose residues, one N-acetyl-D-glucosamine residue, and one D-glucuronic acid residue. An O-acetyl group was also found in the polysaccharide in nonstoichiometric amount. Thus, this polysaccharide had the following structure: [carbohydrate structure: in text].

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A search for fucoidan-degrading enzymes and other O-glycosylhydrolases has been performed among 51 strains of marine bacteria of the family Flavobacteriaceae isolated from red, green, and brown algae, as well as from the sea urchin Strongylocentrotus intermedius and the holothurian Apostichopus japonicus. Over 40% of the studied strains synthesized fucoidanases. The marine bacteria Mesonia algae KMM 3909(T) (an isolate from green alga Acrosiphonia sonderi), as well as Maribacter sp. KMM 6211 and Gramella sp. KMM 6054 (associants of the sea urchin S. intermedius), were the best producers of fucoidanases. Xylose effectively induced the biosynthesis of fucoidanases in these strains. None of the 15 strains of marine bacteria belonging to the genus Arenibacter produced polysaccharide hydrolases.

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The hydrolysis of defatted cells of the marine bacterium Chryseobacterium scophtalmum CIP 104199T with 10% acetic acid (3 h, 100 degrees C) led to an unusual lipid A (LA) (yield 0.6%), obtained for the first time. Using chemical analysis, FAB MS, and NMR spectroscopy, it was shown to be D-glucosamine 1-phosphate acylated with (R)-3-hydroxy-15-methylhexadecanoic and (R)-3-hydroxy-13-methyltetradecanoic acids at the C2 and C3 atoms, respectively. It is similar to the monosaccharide biosynthetic precursor of lipopolysaccharide (LPS), so-called lipid X (LX). Unlike LX, LA can be isolated by the treatment of bacteria with organic solvents only after the preliminary acidic hydrolysis of the cells, which suggests that LA might be strongly, probably chemically, linked to other components of the outer membrane. However, LPS cannot be such a component, because extraction with phenol-water or phenol-chloroform-petroleum ether mixtures in high yields (5.34% and 0.5%, respectively) leads to preparations that do not contain 3-deoxy-D-manno-oct-2-ulopyranosonic acid, 3-hydroxyalkanoic acids, or LA.

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A comparative study of the lipid composition of 26 strains (including type strains) of marine Gammaproteobacteria belonging to the genera Shewanella, Alteromonas, Pseudoalteromonas, Marinobacterium, Microbulbifer, and Marinobacter was carried out. The bacteria exhibited genus-specific profiles of ubiquinones, phospholipids, and fatty acids, which can serve as reliable chemotaxonomic markers for tentative identification of new isolates. The studied species of the genus Shewanella were distinguished by the presence of two types of isoprenoid quinones, namely, ubiquinones Q-7 and Q-8 and menaquinones MK-7 and MMK-7; five phospholipids typical of this genus, namely, phosphatidylethanolamine (PE), phosphatidylglycerol (PG), diphosphatidylglycerol (DPG), lyso-PE, and acyl-PG; and the fatty acids 15:0, 16:0, 16:1 (n-7), 17:1 (n-8), i-13:0, and i-15:0. The high level of branched fatty acids (38-45%) and the presence of eicosapentaenoic acid (4%) may serve as criteria for the identification of this genus. Unlike Shewanella spp., bacteria of the other genera contained a single type of isoprenoid quinone: Q-8 (Alteromonas, Pseudoalteromonas, Marinobacterium, and Microbulbifer) or Q-9 (Marinobacter). The phospholipid compositions of these bacteria were restricted to three components: two major phospholipids (PE and PG) and a minor phospholipid, bisphosphatidic acid (Alteromonas and Pseudoalteromonas) or DPG (Marinobacterium, Microbulbifer, and Marinobacter). The bacteria exhibited genus-specific profiles of fatty acids.

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Two strains KMM 3296 and KMM 3298, isolated from the surface of brown algae Chorda filum and Fucus evanescens thalli and strain KMM 3297, isolated from celomic fluid of holoturian Apostichopus japonicus, were identified as Pseudoalteromonas citrea on the basis of pheno-, geno- and phylotypic features. The studied bacteria were different from other bacteria of the species as to their ability to destruct sulphated polysaccharides of brown algae, fucoidans.

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It was found that Pseudoalteromonas citrea strains KMM 3296 and KMM 3298 isolated from the brown algae Fucus evanescens and Chorda filum, respectively, and strain 3297 isolated from the sea cucumber Apostichopus japonicus are able to degrade fucoidans. The fucoidanases of these strains efficiently degraded the fucoidan of brown algae at pH 6.5-7.0 and remained active at 40-50 degrees C. The endo-type hydrolysis of fucoidan resulted in the formation of sulfated alpha-L-fucooligosaccharides. The other nine strains of P. citrea studied (including the type strain of this species), which were isolated from other habitats, were not able to degrade fucoidan.

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Twenty-five strains of epiphytic marine bacteria isolated from the brown algae Fucus evanescens and Chorda filum and fifty-three bacteria isolated from the sea cucumber Apostichopus japonicus were screened for fucoidanases using fucoidans prepared from the brown algae F. evanescens, Laminaria cichorioides, and L. japonica. Eighteen bacterial epiphytes and thirty-eight bacterial isolates from the sea cucumber were found to contain fucoidanases, which were able to hydrolyze either all of the fucoidans studied or some of them. Bacteria of the genera Cytophaga and Alteromonas/Pseudoalteromonas exhibited the highest fucoidanase activities, which, however, did not exceed the activity of fucoidanases from the already known sources.

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Teichoic acids from the cell walls of marine bacilli Bacillus subtilis CMM (Collection of Marine Microorganisms) 234 (R-1) and B. licheniformis CMM 454 (1-1G-2) were isolated and characterized. These teichoic acids were found to have identical structures and are composed of the glucose, ribitol, and phosphoric acid residues. On the basis of 13C NMR and 31P NMR spectra of the teichoic acids and the products of their dephosphorylation, we established the following structure for the biopolymer: poly[-->5)-4-O-beta-D-glucopyranosylribitol-(1-phospho].

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The distribution of the alpha-N-acetylgalactosidases producers among 856 marine bacteria isolated from sea water, sediments and associated with sponges, mollusks, echinoderms inhabited in different area of the Pacific Ocean and 423 Baikalian microorganisms from fresh water and sponges have been studied. About 24% as marine as Baikalian strains produced this enzyme. The most number of alpha-N-Ac-galactosidase producers were found for marine bacteria genera Aeromonas, Alteromonas and Vibrio (71% and by 60%, respectively) and Baikalian microorganisms genera Aeromonas and Bacillus (40% and 31%, respectively). alpha-N-Acetyl-galactosidase was not found for marine arthrobacters, Flexibacter-Cytophaga and baikalian Micrococcus and Rhodococcus. The promising sources of the alpha-N-Ac-galactosidases were found among Alteromonas and Bacillus.

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