Mucilage from a fresh-water red alga of the genus Batrachospermum

The gelatinous polysaccharides of a Batrachospermum species have been extracted from the alga. The major polysaccharide is acidic and has been separated from neutral polysaccharides by chromatography on DEAE-cellulose. The constituent sugars of the acidic polysaccharide include d- and l-galactose, d-mannose, d-xylose, l-rhamnose, d-glucuronic acid, and two O-methyl sugars, which have been characterized as 3-O-methyl-l-rhamnose (l-acofriose and 3-O-methyl-d-galactose. Partial acid hydrolysis of this polysaccharide has given a complex mixture of neutral and acidic oligosaccharides. The two preponderant acidic oligosaccharides contained galactose and glucuronic acid in 1:1 ratio, suggesting the presence of a repeating sequence of these two residues as a major structural feature of the polysaccharide.     

Composition of a methylated,acidic polysaccharide associated with coccoliths of Emiliania huxleyi (Lohmann) Kamptner

The water-soluble, acidic polysaccharide isolated from the coccoliths of the alga Emiliania huxleyi (Lohmann) Kamptner contains residues of the following sugars: l-galactose, d-glucose, d-mannose, l-mannose, l-rhamnose, l-arabinose, d-ribose, d-xylose, 6-O-methyl-d-mannose, 6-O-methyl-l-mannose, 2,3-di-O-methyl-l-rhamnose, 3-O-methyl-d-xylose, and d-galacturonic acid. l-Mannose, 6-O-methyl-d-mannose, 6-O-methyl-l-mannose, and 2,3-di-O-methyl-l-rhamnose are novel constituents of a polysaccharide. In addition, the presence of sulphate groups was found. Galacturonic acid and sulphate in the polysaccharide bind Ca²⁺ ions apparently in a ratio of one mol of Ca²⁺ per mol of acidic residue. This feature is relevant for the proposed matrix function of the polysaccharide in the formation of the calcified cell-wall plates (coccoliths) of the alga.     

The discernible,structural features of the acidic polysaccharides secreted by different Rhizobium species are the same

Octasaccharide repeating-units have been isolated from the acidic polysaccharides secreted by Rhizobium trifolii strain NA30, R. trifolii strain LPR5, R. leguminosarum strain LPR1, and R. phaseoli strain LPR49. (R. trifolii is the symbiont of clover, R. leguminosarum, of peas, and R. phaseoli, of beans). The repeating units were formed by treating the polysaccharides with an enzyme produced by a bacteriophage. The glycosyl sequence and the structures and locations of the non-glycosyl substituents were shown to be identical for repeating units derived from all of these polysaccharides, except for that derived from the polysaccharide produced by R. trifolii NA30. Therefore, the discernible structural features of the acidic polysaccharides secreted by Rhizobium species cannot be the determinant of host specificity. In support of this conclusion is the observation that R. trifolii LPR5045, produced by curing R. trifolii LPR5 of its Sym plasmid (the Sym plasmid is required for symbiosis and host specificity), secreted a polysaccharide having the same structure (including identities and locations of nonglycosyl substituents) as that of the polysaccharide secreted by its plasmid-containing parent. Thus, the structural genes that encode for synthesis of the acidic polysaccharide secreted by R. trifolii LPR5045 are not located on the Sym plasmid, and neither are the genes that encode for synthesis and attachment of non-glycosyl substituents of the polysaccharide. The possibility remains that a quantitatively minor component of the acidic polysaccharide could be a host-specific determinant.     

Structural investigation of the acidic polysaccharide secreted by Zoogloea ramigera 115

Batch-culture growth of Zoogloea ramigera 115 in a defined medium produced a weakly acidic polysaccharide containing glucose and galactose residues, and (S)-pyruvic acetal groups. Analytical results indicated that the polysaccharide does not have a simple repeating-unit. Mainly with the aid of Smith degradation of the native polysaccharide and oxidation and subsequent β-elimination of the methylated and then depyruvylated polysaccharide, some structural features of the polysaccharide were identified.     

Polysaccharide components of the seed-coat mucilage from hyptis suaveolens

The mucilage isolated from the seed coat of Hyptis suaveolens contains l-fucose, d-xylose, d-mannose, d-galactose, d-glucose and 4-O-methyl-d-glucuronic acid in the mol ratios 1.0:2.5:1.5:7.0:12.5:1.1. Fractionation of the mucilage with Fehling's solution gave a neutral and an acidic polysaccharide. The neutral polysaccharide appears to be homogeneous and is composed of d-mannose, d-galactose and d-glucose in the mol ratios 1.0:4.5:7.5. The acidic polysaccharide is composed of l-fucose, d-xylose and 4-O-methyl-d-glucuronic acid in the mol ratios 1.0:2.5:1.1. It is homogeneous on gel filtration, DEAE-cellulose chromatography, sedimentation analysis and electrophoresis.     

Lipid-linked saccharides formed during pullulan biosynthesis in Aureobasidium pullulans

Radioactive glycolipids were extracted from cells of Aureobasidium pullulanspulsed with d-[¹⁴C]glucose. Labelled, alkali-stable lipids were resolved into one neutral and two acidic fractions. The neutral fraction was stable to mild hydrolysis with acid, whereas the acidic fractions could be hydrolysed, yielding d-glucose and a series of oligosaccharides having mobilities corresponding to those of isomaltose, panose, and isopanose. Amyloglucosidase (EC 3.2.1.3) catalysed the hydrolysis of 60% of the liberated radioactive oligosaccharides to d-glucose, indicating the presence of (1→4)-α- and (1 → 6)-α-d-glucosidic bonds. Since these lipid-linked saccharides are produced during pullulan biosynthesis in A. pullulans, it is proposed that they are intermediates in the biosynthetic pathway of that extracellular polysaccharide. A mechanism incorporating these glycolipids into a possible scheme of polysaccharide assembly is presented.     

Polysaccharide component in the stigmatic exudate from Lilium longiflorum

The polysaccharide component of the stigmatic exudate from Lilium longiflorum has the composition, arabinose (26%), rhamnose (6%), galactose (57%) and glucuronic acid (11%). The highly branched polysaccharide bears a striking resemblance to the acidic polysaccharide exudate from Araucaria bidwillii in belonging to the galactan group and in carrying outer chains terminated by arabinofuranose, rhamnopyranose, galactopyranose and glucuronic acid residues. Both polysaccharides contain the sequence O-rhamnopyranosyl-(1→4)-glucopyranosyluronic acid-(1→6)-galactopyranose in some of the outer chains.     

Structural features of a sulphated,fucose-containing polysaccharide from the brown seaweed dictyota dichotoma

A sulphated heteropolysaccharide (～15% of the acid-extractable material) isolated from the brown alga Dictyota dichotoma contains residues of D-glucuronic acid, D-galactose, D-mannose, D-xylose, and L-fucose¹. Partial hydrolysis of the polysaccharide with acid gave one neutral and two acidic oligosaccharides. The behaviour towards periodate of the polysaccharide before and after partial hydrolysis, alkali-treatment, and methanolysis has been studied. Evidence is thereby provided that the polysaccharide is partially sulphated and composed of (1→4)-linked residues of D-glucuronic acid, D-galactose, D-mannose, and D-xylose, and (1→2)-linked L-fucose.     

Sterol-binding polysaccharides of Rhizopus arrhizus, Penicillium roquefortii and Saccharomyces carlsbergensis

Polysaccharides that bind with sterols and render them water-soluble were isolated from two mycelial fungi, Rhizopus arrhizus and Penicillium roquefortii and a yeast Saccharomyces carlsbergensis. The polysaccharides from R. arrhizus and S. carlsbergensis were accompanied by small quantities of phosphorus, protein and lipid, none of which significantly influenced the binding of sterol to polysaccharide. The chemical composition and sterol-binding properties of the polysaccharides from the filamentous species were almost identical, but differed significantly from those of the yeast polysaccharide. The principal sterol-binding polysaccharide of S. carlsbergensis was identified as a mannan and that of the filamentous fungi as a glucan(s). The binding capacity of the purified yeast polysaccharide was almost two-fold greater than that of R. arrhizus and P. roquefortii.     

Structural investigations of the extracellular polysaccharides elaborated by Beijerinckia mobilis

The extracellular mucilage from Beijerinckia mobilis, a member of the Azotobacteriaceae, after removal of contaminating protein, was separated into a neutral polysaccharide (N-2, 10%); a neutral, dialysable fraction (N-1, 5%), consisting of glucose and oligosaccharides containing glucose, arabinose, and rhamnose; and an acidic polysaccharide (85%). N-2 (mol. wt, 1900) was highly branched and comprised glucopyranose, mannopyranose, and arabinofuranose residues (1:1:1). The various linkages were determined. The acid fraction was a polymer of high molecular weight composed of L-guluronic acid (65%), D-glucose (15%), and D-glycero-D-mannoheptose (20%), together with acetic and pyruvic acids. From the results of methylation, periodate oxidation, and partial hydrolysis, a branched molecule with a backbone of guluronic acid and heptose, and side chains of glucose and guluronic acid is proposed. Pyruvic acid was found to be acetal-linked to 2?5% of the heptose residues. The similarities between this polysaccharide and that from the related species Azotobacter indicum are discussed.     

Physical and chemical properties of the mucin secreted by Drosera capensis

The mucin droplets secreted by the leaves of Drosera capensis consist of a 4 % aq. solution of an acidic polysaccharide containing xylose, mannose,     

Effects of salinity on synthesis of DNA,acidic polysaccharide,and ichthyotoxin in Gymnodinium breve

A Florida red tide organism, Gymnodinium breve Davis, an unarmored dinoflagellate, was grown in enriched sea water media at salinities 20–43% and constant illumination. Use of lowest (23%) and highest (43%) salinities resulted in death within 24 hr of inoculation, though good growth was obtained at all intermediate salinities (29–39%), in accord with field observation. Rates of synthesis of DNA, acidic polysaccharide and ichthyotoxin were determined as a function of salinity and growth constant (K₁₀). The relative rate of' synthesis of DNA or polysaccharide increased linearly with growth constant. Mean cell volumes, determined during log-phase growth, showed a positive correlation with doubling time. Hemolytic activity was detected in cell extracts only at high toxin concentrations (0.35–2.05 mg of ichthyotoxin). No significant difference was noted in hemolytic activity of extracts of cells grown in high (34%) or low (26%) salinity. The rate of toxin synthesis showed a linear decrease with the rate of DNA or polysaccharide synthesis.     

Novel O-antigen of Hafnia alvei PCM 1195 lipopolysaccharide with a teichoic acid-like structure

The lipopolysaccharide (LPS) of Hafnia alvei strain PCM 1195 was obtained by the hot phenol/water method. The O-specific polysaccharide was released by mild acidic hydrolysis and isolated by gel filtration. The structure of the O-specific polysaccharide was investigated by ¹H, ¹³C, and ³¹P NMR spectroscopy, MALDI-TOF MS, and GC-MS, accompanied by monosaccharide and methylation analysis. It was concluded that the O-specific polysaccharide is composed of a hexasaccharide repeating units interlinked with a phosphate group: {→4-α-d-Glcp-(1→3)-α-l-FucpNAc-(1→3)-[α-d-Glcp-(1→4)]-α-d-GlcpNAc-(1→3)-α-l-FucpNAc-(1→4)-α-d-Glcp-(1→P}_n.     

Composition and properties of the extracellular polysaccharide produced by arthrobacter stabilis NRRL B-3225

The extracellular polysaccharide produced by Arthrobacter stabilis NRRL B-3225 contains d-glucose, d-galactose, pyruvic acid, O-succinyl, and O-acetyl in the approximate molar ratio of 6:3:1:1:1.5. Succinyl is linked as its half-ester, making it a readily removable, acidic function that imparts versatility to the polysaccharide both for fundamental research and for commercial use. The viscosity of aqueous, salt-free solutions of both native and deacylated polymer is relatively low, but atypical of anionic polysaccharides, increases rapidly in the presence of salts, acids, or alkali.     

4-O[(S)-1-carboxyethyl]-D-glucuronic acid: a component of the Klebsiella type 37 capsular polysaccharide

The acidic sugar component in the Klebsiella type 37 capsular polysaccharide (K 37) has been identified as 4-O-[(S)-1-carboxyethyl]-D-glucuronic acid. The identification is based upon chemical and spectroscopic studies, and the identity of the carboxyl-reduced sugar, 4-O-[(S)-2-(1-hydroxy)propyl]-D-glucose and derivatives, with the corresponding substances synthesized by an unambiguous route.     

Structures of Cinnzeylanine and Cinnzeylanol,Polyhydroxylated Pentacyclic Diterpenes from Cinnamonum zeylanicum Nees

A bacterium isolated as resistant to alkyldimethylbenzylammonium chloride (benzalkonium chloride, BC) and tentatively identified as Enterobacter cloacae, was induced by BC to produce acidic polysaccharide. The optimum concentration of BC for production of the polysaccharide was 0.1% and the polysaccharide produced amounted to 1.0-2.0 mg per ml of culture broth. The best carbon and nitrogen sources for the polysaccharide production were glycerol and polypeptone.

The acidic polysaccharide was consisted of fucose, galactose, glucose, glucuronic acid, pyruvate, and acetate, like colanic acid. The production of the acidic polysaccharide was not induced by the addition of trimethylbenzylammonium chloride and tetramethylammonium chloride, but it was induced by p-fluorophenylalanine, and the results are discussed.     

Structural studies of the extracellular polysaccharides of Rhizobium japonicum strains 71A,CC708, and CB1795

Each of the serologically related, title strains produced extracellular polysaccharides that were mixtures of an acidic polysaccharide and smaller proportions of a glucan. These were separated by column chromatography and the structures of the acidic polysaccharides investigated by alkylation, specific sequential degradation, and periodate oxidation in conjunction with ¹H-n.m.r. spectroscopy. The polysaccharides from the three strains appear to be identical rhamno-4-O-methyl-glucuronans, having the following tetrasaccharide repeating-unit.

The molecular weight of the polysaccharides of strains CC708 and CB1795 was of the order of 65,000–70,000.     

An acidic polysaccharide from the seeds of Ocimum adscendens

The mucilaginous polysaccharide-complex found in the seeds O. adscendens contains an acidic polysaccharide which has been isolated. It is composed of D-galactose (～ 20%), D-galacturonic acid (～ 35%) and L-rhamnose (～ 39%). Methylation analysis using GC and GC/MS, Smith degradation, isolation of an acidic oligosaccharide from partial hydrolysates, and enzymic hydrolysis using β-D-galactosidase indicated the polysaccharide backbone to be → 4)-GalpA-(1 → 2)-L-rhap-(1 →. Nearly two-thirds of the rhamnopyranosyl units are 0-4 substituted by D-galactopyranosyl non-reducing end groups.     

Xylans from the tropical grass Panicum maximum

Two xylans have been isolated from the mature tissues of the tropical grass Panicum maximum—an arabino(4-O-methylglucurono)xylan and an acidic galactoarabinoxylan. Both consist of a main chain of β(1 → 4) linked d-xylopyranosyl residues. The former has average of ca 46 such residues to which are attached ca 7 l-arabinofuranosyl and (ca 2 4-O-methyl-d-glucopyranuronosyl residues at C3 and C2 positions respectively. The acidic galactoarabinoxylan has a $\text{DP}$_n of ca 90 and contains arabinose, galactose, xylose and uronic acid residues in the molar ratio 10:5:22:4. Methylation analysis and periodate oxidation indicated the highly branched nature of this polysaccharide.     

Structural studies of an acidic polysaccharide from Ocimum basilicum seeds

An acidic polysaccharide isolated from the seeds of Ocimum basilicum by DEAE-cellulose fractionation was ～92% pure, having an associated glucan impurity (～8%). The polysaccharide is composed of d-xylose, l-arabinose, l-rhamnose, and d-galacturonic acid in the molar ratios 15:9:7:12, together with traces or galactose and glucose. Methylation analysis indicated that the polysaccharide contained a (1→4)-linked xylan backbone carrying branch-points at C-2 and C-3 of the xylosyl residues, and revealed the structural features of the side chains. Periodateoxidation and Smith-degradation studies support the results of methylation analysis.