STRUCTURAL FEATURES OF TWO EXTRACELLULAR POLYSACCHARIDES FROM SERRATIA MARCESCENS

1965 ◽  
Vol 43 (11) ◽  
pp. 2929-2939 ◽  
Author(s):  
Robert Young ◽  
G. A. Adams
Keyword(s):  
Serratia Marcescens ◽  
Culture Filtrate ◽  
Cetyltrimethylammonium Bromide ◽  
Main Chain ◽  
Deae Cellulose ◽  
Structural Features ◽  
Ethanol Solution ◽  
Molar Ratio ◽  
Extracellular Polysaccharides ◽  
End Groups

A polysaccharide insoluble in acidified ethanol solution has been isolated from a culture filtrate of Serratia marcescens. Fractionation by cetyltrimethylammonium bromide ("Cetavlon") and by diethylaminoethyl (DEAE) cellulose yielded a polysaccharide which was electrophoretically homogeneous and contained D-glucose, L-rhamnose, D-galactose, L-glycero-D-mano-heptose, D-glycero-D-manno-heptose, glucosamine, and galactosamine in an approximate molar ratio of 6.5:3.5:0.5:1.0:0.5:1.0:0.2. However, following methylation it was found that the fully methylated polysaccharide could be fractionated by organic solvents into a rhamnoglucan and a heptoglucan. Both polysaccharides contained lipid material consisting mainly of hydroxy myristic acid and hydroxy lauric acid. The main chain of the rhamnoglucan was composed of (1 → 3) linked L-rhamnopyranose units and (1 → 4) linked D-glucose units with the non reducing end groups being D-glucose; some branching occurred through D-glucose units. The heptoglucan was composed mainly of chains of (1 → 4) linked D-glucose units with smaller amounts of (1 → 6) linked D-glucose and (1 → 2) linked D-glycero-D-manno-heptose units; these chains were terminated by D-glucopyranose and L-glycero-D-manno-heptose end groups.

EXTRACELLULAR POLYSACCHARIDES OF SERRATIA MARCESCENS

1964 ◽  
Vol 42 (10) ◽  
pp. 1403-1413 ◽  
Author(s):  
G. A. Adams ◽  
S. M. Martin
Keyword(s):  
Serratia Marcescens ◽  
Culture Filtrate ◽  
Glucuronic Acid ◽  
Carbon Sources ◽  
Growth Period ◽  
The Other ◽  
Extracellular Polysaccharides ◽  
Active Growth ◽  
Electrophoretic Behavior ◽  
Active Growth Period

Growth of Serratia marcescens on sucrose, D-glucose, D-galactose, and D-xylose as carbon sources did not affect the composition of the extracellular polysaccharides significantly. D-Glucose was the major component with lesser amounts of D-mannose, heptose, L-fucose, and L-rhamnose. Rhamnose did not appear until near the end of the active growth period and increased proportionately more than the other sugars thereafter. From the culture filtrate after 20 hours growth on sucrose, two acidic polysaccharides were isolated. They were markedly different in composition and electrophoretic behavior although both contained glucose as their major component. One was characterized by a relatively high content of rhamnose and heptose, the other by the presence of mannose; both contained glucuronic acid. Other impure polysaccharides were isolated from the culture filtrate. It seems likely that S. marcescens produced a spectrum of rather similar extracellular polysaccharides of which the two isolated ones comprise the main types.

ISOLATION AND SOME STRUCTURAL FEATURES OF A POLYSACCHARIDE FROM BIRCH SAP

1964 ◽  
Vol 42 (9) ◽  
pp. 2093-2100 ◽  
Author(s):  
B. Urbas ◽  
G. A. Adams ◽  
C. T. Bishop
Keyword(s):  
Glucuronic Acid ◽  
Xylem Sap ◽  
Periodate Oxidation ◽  
Structural Features ◽  
The Other ◽  
Molar Ratio ◽  
Plant Products ◽  
End Groups

A polysaccharide, precipitated by cetyltrimethylammonium hydroxide from the non-dialyzable portion of birch xylem sap, contained D-galactose, D-mannose, and D-glucose in a molar ratio of 2:1.4:1 and small amounts of D-glucuronic acid. Periodate oxidation studies indicated that the polysaccharide was branched and contained a high proportion of periodate-resistant monosaccharides. This was confirmed by methylation and hydrolysis which yielded 2,3,4,6-tetra-O-methyl-D-glucose (2.0 moles); 2,4,6-tri-O-methyl-D-mannose (0.9 mole); 2,4,6-tri-O-methyl-D-galactose (3.8 moles); unidentified tri-O-methyl hexose (1.2 moles); and 3,5-di-O-methyl-D-mannose (1.8 moles). The latter, a new di-O-methyl-D-mannose, snowed the presence of D-mannofuranose units in the polysaccharide. This, together with the 1 → 3 linked α-D-mannopyranose units, makes this polysaccharide unique among plant products. Immunochemical tests with antipneumococcal and antiparatyphoid B horse sera confirmed the presence of D-glucuronic acid and D-glucopyranose non-reducing end groups and supported the other structural conclusions by showing that there were few, if any, 1 → 4 and 1 → 6 linked D-mannopyranose units or D-galactopyranose non-reducing end groups.

Studies on the Preliminary Characterization of a Novel Exopolysaccharide Produced by Streptococcus thermophilus Strain from Tibetan Kefir Grain

2013 ◽  
Vol 690-693 ◽  
pp. 1374-1377 ◽  
Author(s):  
Shu Juan Jiang ◽  
Fang Qian ◽  
Xiao Hui Ren ◽  
Guang Qing Mu
Keyword(s):  
High Performance ◽  
Deae Cellulose ◽  
Gel Permeation Chromatography ◽  
Streptococcus Thermophilus ◽  
Structural Features ◽  
Molar Ratio ◽  
Partial Hydrolysis ◽  
The Novel ◽  
Average Molecular Mass ◽  
Kefir Grain

The novel exopolysaccharide (EPS) was produced by a streptococcus thermophilus strain isolated from Tibetan kefir grain, and it was purified using DEAE cellulose 52 and DEAE Sepharose CL-6B column chromatography. Then it was eluted as a single symmetrical narrow peak on high-performance gel-permeation chromatography (HPGPC) and the average molecular mass was estimated to be 30,092Da. Infrared spectrum analysis indicated it had characteristic glycosidic structures. Gas chromatography showed that the EPS is composed of mannose and glucose in a molar ratio of 2.6:1 with trace galactose. The structural features of EPS were investigated by partial hydrolysis with acid, methylation analysis and NMR spectroscopy analysis. The results revealed that the main backbone chain of EPS was (23)-β-D-Manp, (34)-β-D-Manp, (23,6)-α-D-Glcp and trace amounts of galactose.

scholarly journals Copper(II) 2,2-Bis(Hydroxymethyl)Propionate Coordination Compounds with Hexamethylenetetramine: From Mononuclear Complex to One-Dimensional Coordination Polymer

Molecules ◽  
2021 ◽  
Vol 26 (11) ◽  
pp. 3358
Author(s):  
Sadaf Rauf ◽  
Agata Trzesowska-Kruszynska ◽  
Tomasz Sierański ◽  
Marcin Świątkowski
Keyword(s):  
Coordination Polymer ◽  
Coordination Compounds ◽  
Structural Diversity ◽  
Structural Features ◽  
Mononuclear Complex ◽  
Molar Ratio ◽  
One Dimensional ◽  
1D Coordination Polymer ◽  
Copper Coordination ◽  
Stretching Vibrations

Three new copper coordination compounds derived from 2,2-bis(hydroxymethyl)propionic acid (dmpa) and hexamethylenetetramine (hmta) were obtained and their crystal structures were determined. The stoichiometry of the reagents applied in the syntheses reflects the metal to ligand molar ratio in the formed solid products. Due to the multiple coordination modes of the used ligands, wide structural diversity was achieved among synthesized compounds, i.e., mononuclear [Cu(dmp)2(hmta)2(H2O)] (1), dinuclear [Cu2(dmp)4(hmta)2] (2), and 1D coordination polymer [Cu2(dmp)4(hmta)]n (3). Their supramolecular structures are governed by O—H•••O and O—H•••N hydrogen bonds. The compounds were characterized in terms of absorption (UV-Vis and IR) and thermal properties. The relationships between structural features and properties were discussed in detail. Owing to discrepancies in the coordination mode of a dmp ligand, bidentate chelating in 1, and bidentate bridging in 2 and 3, there is a noticeable change in the position of the bands corresponding to the stretching vibrations of the carboxylate group in the IR spectra. The differences in the structures of the compounds are also reflected in the nature and position of the UV-Vis absorption maxima, which are located at lower wavelengths for 1.

scholarly journals Polysaccharide Derived from Nelumbo nucifera Lotus Plumule Shows Potential Prebiotic Activity and Ameliorates Insulin Resistance in HepG2 Cells

Polymers ◽  
2021 ◽  
Vol 13 (11) ◽  
pp. 1780
Author(s):  
Bao Le ◽  
Pham-Thi-Ngoc Anh ◽  
Seung-Hwan Yang
Keyword(s):  
Insulin Resistance ◽  
Hepg2 Cells ◽  
Structural Characteristics ◽  
Physicochemical Characterization ◽  
Deae Cellulose ◽  
Hot Water ◽  
Nelumbo Nucifera ◽  
Molar Ratio ◽  
Prebiotic Activity ◽  
Insulin Resistant

Polysaccharides are key bioactive compounds in lotus plumule tea, but their anti-diabetes activities remain unclear. The purpose of this study was to investigate the prebiotic activities of a novel polysaccharide fraction from the Nelumbo nucifera lotus plumule, and to examine its regulation of glucose metabolism in insulin-resistant HepG2 cells. The N. nucifera polysaccharide (NNP) was purified after discoloration, hot water extraction, ethanol precipitation, and DEAE-cellulose chromatography to obtain purified polysaccharide fractions (NNP-2). Fourier transform infrared spectroscopy was used to analyze the main structural characteristics and functional group of NNP-2. Physicochemical characterization indicated that NNP-2 had a molecular weight of 110.47 kDa and consisted of xylose, glucose, fructose, galactose, and fucose in a molar ratio of 33.4:25.7:22.0:10.5:8.1. The prebiotic activity of NNP-2 was demonstrated in vitro using Lactobacillus and Bifidobacterium. Furthermore, NNP-2 showed bioactivity against α-glucosidase (IC50 = 97.32 µg/mL). High glucose-induced insulin-resistant HepG2 cells were used to study the effect of NNP-2 on glucose consumption, and the molecular mechanism of the insulin transduction pathway was studied using RT-qPCR. NNP-2 could improve insulin resistance by modulating the IRS1/PI3K/Akt pathway in insulin-resistant HepG2 cells. Our data demonstrated that the Nelumbo nucifera polysaccharides are potential sources for nutraceuticals, and we propose functional food developments from the bioactive polysaccharides of N. nucifera for the management of diabetes.

scholarly journals Chemical synthesis of all-trans-β-retinoyl phosphate

1976 ◽  
Vol 159 (3) ◽  
pp. 799-801 ◽  
Author(s):  
J P Frot-Coutaz ◽  
L M de Luca
Keyword(s):  
Retinoic Acid ◽  
Chemical Synthesis ◽  
Cellulose Acetate ◽  
Silica Gel ◽  
Absorption Maximum ◽  
Ammonium Acetate ◽  
Deae Cellulose ◽  
Thin Layers ◽  
Molar Ratio ◽  
Chloroform Methanol

all-trans-β-Retinoic acid is phosphorylated to retinoyl phosphate by bis(triethylamine) phosphate with yields of 10-15%. The product is soluble in methanol and is eluted from DEAE-cellulose acetate at a concentration of 0.1M-ammonium acetate in 99% (v/v) methanol. Its phosphate/retinoic acid molar ratio is 1. Retinoyl phosphate has an absorption maximum at 360nm in methanol, whereas retinoic acid has a maximum at 350 nm. The compound is hydrolysed at pH2 and pH13 for 20 min at 37 degrees C, but is relatively stable under the same conditions at pH4, 6, 8 and 10. Retinoyl phosphate (RF 0.1) can be separated from retinyl phosphate (RF 0.2) by chromatography on thin layers of silica gel in chloroform/methanol/water (60:25:4, by vol.).

scholarly journals Microbubbles Decorated with Dendronized Magnetic Nanoparticles for Biomedical Imaging. Effective Stabilization via Fluorous Interactions

2019 ◽  
Author(s):  
Da Shi ◽  
Justine Wallyn ◽  
Dinh-Vu Nguyen ◽  
Francis Perton ◽  
Delphine Felder-Flesch ◽  
...  
Keyword(s):  
Molar Ratio ◽  
Aqueous Dispersions ◽  
Force Microscopy ◽  
Atomic Force ◽  
Microscopy Investigation ◽  
End Groups ◽  
Mixed Films ◽  
Effective Stabilization ◽  
Effective Result ◽  
End Group

Dendrons fitted with three oligoethylene glycol (OEG) chains, one of which carrying a fluorinated or hydrogenated end group, and bearing a bisphosphonate polar head (C n X2 n +1OEG8Den, X = F or H; n= 2 or 4) were synthesized and grafted on the surface of iron oxide nanoparticles (IONPs) for microbubble-mediated imaging and therapeutic purposes. The size and stability of the dendronized IONPs (IONP@C n X2 n +1OEG8Den) in aqueous dispersions were monitored by dynamic light scattering. Investigation of the spontaneous adsorption of IONP@C n X2 n +1OEG8Den at the interface between air - or air saturated with perfluorohexane - and an aqueous phase establishes that exposure to the fluorocarbon gas markedly increases the rate of adsorption of the dendronized IONPs to the gas/water interface and decreases the equilibrium interfacial tension. This suggests that fluorous interactions are at play between the supernatant fluorocarbon gas and the fluorinated end groups of the dendrons. Furthermore, small, stable perfluorohexane-stabilized microbubbles (MBs) with a dipalmitoylphosphatidylcholine (DPPC) shell that incorporates IONP@C n X2 n +1OEG8Den (DPPC/Fe molar ratio 28:1) were prepared and characterized using both optical microscopy and an acoustical method of size determination. The dendrons fitted with fluorinated end groups lead to smaller and more stable MBs than those fitted with hydrogenated groups. The most effective result is already obtained with C2F5, for which MBs, ~1.0mm in radius, reach a half-life of ~6.0 h. An atomic force microscopy investigation of spin-coated mixed films of DPPC/IONP@C2X5OEG8Den combinations (molar ratio 28:1) shows that the IONPs grafted with the fluorinated dendrons are located within the phospholipid film, while those grafted with the hydrocarbon dendrons are completely absent from the phospholipid film.

Synthesis of Poly(acrylamide-Methacrylate)-G-Octylphenyl Polyoxyethylene and its Micellar Behavior in Aqueous Solution

2011 ◽  
Vol 239-242 ◽  
pp. 3337-3341
Author(s):  
Dong Xia Zhang ◽  
Wen Hui Hu ◽  
Fang Ping Wang ◽  
Lin Ke Xue ◽  
Xin Zhen Du
Keyword(s):  
Aqueous Solution ◽  
Graft Copolymer ◽  
Main Chain ◽  
Radical Copolymerization ◽  
Molar Ratio ◽  
Free Radical Copolymerization ◽  
Transmission Electron ◽  
Spherical Micelles ◽  
Acrylamide Monomer ◽  
Poly Acrylamide

An amphiphilic graft copolymer with poly(acrylamide-methacrylate) as a main chain and octylphenyl polyoxyethylene as side chains (P(AM-MA)-g-C8PhEO10) was successfully synthesized via free radical copolymerization. The structure and the composition of the graft copolymer were characterized by FTIR, 1H-NMR and elemental analysis (EA) in detail. The absolute molecular weight of the copolymer is 1.304×106, as determined by static light scattering (SLS). The molar ratio of acrylamide monomer to the macromonomer is 33:1 in the copolymer and 53 C8PhEO10 branch chains attach to a P(AM-MA) backbone. The micellar behavior of P(AM-MA)-g-C8PhEO10 was preliminarily studied by means of surface tension measurements, transmission electron microscope (TEM) in aqueous solution. It was found that the stable spherical micelles with core-shell structure are formed and polymolecular micelles are larger and more compact than monomolecular micelles. In addition, the graft copolymer has favorable thermal stability.

Biosynthesis of glucosyl monophosphoryl undecaprenol and its role in lipoteichoic acid biosynthesis

1982 ◽  
Vol 152 (2) ◽  
pp. 616-625
Author(s):  
D J Mancuso ◽  
T H Chiu
Keyword(s):  
Thin Layer ◽  
Polyacrylamide Gel Electrophoresis ◽  
Sodium Dodecyl ◽  
Deae Cellulose ◽  
Lipoteichoic Acid ◽  
Molar Ratio ◽  
Streptococcus Sanguis ◽  
Chromatographic Profile ◽  
Hydrolysis Of ◽  
Cellulose Column

A glucophospholipid was detected in an incubation mixture containing UDP-glucose, MgCl2, ATP, and a particulate enzyme prepared from Streptococcus sanguis. The synthesis of this lipid was inhibited strongly by UDP and moderately by UMP. The molar ratio of glucose to phosphate in the purified lipid was found to be 1:1. Glucose and glucose 1-phosphate were released by mild alkaline hydrolysis of the glucophospholipid. The lipid produced by mild acid degradation of the purified lipid yielded a thin-layer chromatographic profile similar to that of acid-treated undecaprenol. One of the minor components exhibited the same mobility as untreated undecaprenol. To characterize further the lipid moiety of the glucophospholipid, a polyisoprenol was purified from the neutral lipid of S. sanguis. The polyisoprenol was converted in the presence of ATP, UDP-glucose, and the particulate enzyme into a lipid which exhibited the same thin-layer chromatographic mobility as the glucophospholipid. The structure of the polyisoprenol was determined by nuclear magnetic resonance and mass spectrometry to be an undecaprenol with an internal cis-trans ratio of 7:2. These results indicate that the glucophospholipid is glucosyl monophosphoryl undecaprenol. The glucosyl moiety of the glucophospholipid was shown to be incorporated in the presence of the particulate enzyme into a macromolecule which was characterized as a lipoteichoic acid by sodium dodecyl sulfate-polyacrylamide gel electrophoresis and DEAE-cellulose column chromatography. This result indicates that glucosyl monophosphoryl undecaprenol is the direct glucosyl donor in the synthesis of lipoteichoic acid.

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