N. M. Gorshkova

Structure of a phosphorylated polysaccharide from Shewanella putrefaciens strain S29

A phosphorylated polysaccharide was isolated from the aqueous layer of the phenol-water extract of a non-halophilic bacterium Shewanella putrefaciens strain S29. The glycosyl phosphate linkage in the polysaccharide was split under mild acid conditions to give, after borohydride reduction, a phosphorylated oligosaccharide-alditol. On the basis of sugar analysis and 1H, 13C and 31P NMR spectroscopy, including 2D COSY, relayed COSY, rotating-frame NOE spectroscopy (ROESY), heteronuclear 13C,1H COSY, and H-detected heteronuclear 1H,31P multiple-quantum coherence (HMQC), it was concluded that the polysaccharide is built up of tetrasaccharide-phosphate repeating units having the following structure: [sequence: see text] where QuiNAc and Qui4NAc are 2-acetamido-2,6-dideoxyglucose and 4-acetamido-4,6-dideoxyglucose, respectively.

Degradation of fucoidan by the marine proteobacterium Pseudoalteromonas citrea

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°C. The endo-type hydrolysis of fucoidan resulted in the formation of sulfated α-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.

Structure of the acidic polysaccharide chain of the lipopolysaccharide of Shewanella alga 48055

A lipopolysaccharide (LPS) with an acidic polysaccharide chain was isolated from the bacterium Shewanella alga strain 48055 and cleaved selectively at the glycosidic linkage of N-acetylneuraminic acid to give a tetrasaccharide. Studies of the tetrasaccharide and the O-deacylated LPS by 1H and 13C NMR spectroscopy, including 2D COSY, TOCSY, NOESY, rotating-frame NOE spectroscopy (ROESY), and H-detected 1H, 13C heteronuclear multiple-quantum coherence (HMQC) experiments, revealed the following structure of the polysaccharide repeating unit: -->3)-beta-D-GalpA6GroN-(1-->3)-beta-D-GlcpNAc-(1-->3)-alpha-D- GalpA6GroN- (1-->4)-alpha-Neup5Ac-(2--> where GroN is an amidically linked residue of 2-amino-1,3-propanediol (2-amino-2-deoxyglycerol). A similar structure, but with 2-acetamido-2,6-dideoxy-D-glucose instead of 2-acetamido-2-deoxy-D-glucose, has been reported previously for the polysaccharide chain of a non-O1 Vibrio cholerae H11 LPS [E. V. Vinogradov, O. Holst, J.E. Thomas-Oates, K.W. Broady, and H. Brade, Eur. J. Biochem., 210 (1992) 491-498].

Lipid Composition of Novel Shewanella Species Isolated from Far Eastern Seas

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.

[Elucidation of structure of lipid A from the marine Gram-negative bacterium Pseudoalteromonas haloplanktis ATCC 14393T].

The chemical structure of lipid A, from the marine γ-proteobacterium Pseudoalteromonashaloplanktis АТСС 14393Т, a main product of lipopolysaccharide hydrolysis (1% AcOH), was determined using chemical methods and NMR spectroscopy. The lipid A was shown to be β-1,6-glucosaminobiose 1,4′-diphosphate acylated with two (R)-3-hydroxyalkanoic acid residues at C3 and C3′ and amidated with one (R)-3-hydroxydodecanoyl and one (R)-3-dodecanoyloxydodecanoyl residue at N2 and N2′, respectively.

Structure of O-Specific Polysaccharide from Pseudoalteromonas nigrifaciens Strain KMM 161

AbstractOn mild acid degradation of the lipopolysaccharide of the marine microorganism Pseudoalteromonas nigrifaciens KMM 161 an O-specific polysaccharide containing D-galactose, 2-acetamido-2-deoxy-D-glucose, 3,6-dideoxy-3-(4-hydroxybutyramido)-D-galactose, and 2-acetamido-2-deoxy-L-guluronic acid residues was obtained. From the results of Smith degradation, O-deacetylation of the polysaccharide, and NMR spectroscopy the following structure of the tetrasaccharide repeating unit of the O-specific polysaccharide was established:

Structure of the O-specific polysaccharide from Pseudoalteromonas elyakovii sp. nov. CMM 162

\begin{gathered} \to {4)} - {\alpha } - {L} - {Gul}p - {NAcA} - {(1} \to {4)} - {\beta } - {D} - {Gl}cp{NAc} - {(1} \to {3)} - {\alpha } - {D} - {Gal}p - {(1} \to \hfill \\ { 3 4} \hfill \\ { } \uparrow { } \uparrow \hfill \\ { OAc 1} - {\alpha } - {D} - {Fuc}p3{NR} \hfill \\ \end{gathered}

Structure of the phenol-soluble polysaccharide from Shewanella putrefaciens strain A6.

where R: -CO-CH2-CH2-CH2-OH. It should be noted that the same structure occurs in the antigenic polysaccharide of Pseudoalteromonas nigrifaciens KMM 158 described earlier as Alteromonas macleodii 2MM6.