The chemical constitution of lipid A from Serratia marcescens

1970 ◽  
Vol 48 (1) ◽  
pp. 55-62 ◽  
Author(s):  
G. A. Adams ◽  
Prem Pal Singh

The lipopolysaccharide of Serratia marcescens, under mild hydrolysis conditions (0.25 N H2SO4 for 2.5 h at 100°), yielded a lipid A containing D-glucosamine, fatty acids, acetyl and phosphate groups (approximate molar ratio 3:9:4:2), a small amount of ethanolamine, and a trace of galactosamine. Lipid A on methylation and subsequent hydrolysis yielded 3,4-di-O-methyl-D-glucosamine and 3,4,6-tri-O-methyl-D-glucosamine identified by gas–liquid chromatography as their glucitol acetates. These sugars were further identified by ninhydrin degradation to yield 2,3-di-O-methyl-L-arabinose and 2,3,5-tri-O-methyl-L-arabinose. From these findings, it was concluded that the D-glucosamine units in the lipid A were linked 1 → 6. A negative optical rotation of the lipid A suggested a β linkage. On the basis of the glycosidic linkage evidence and additional compositional data, a possible structure for the lipid A of S. marcescens is proposed and discussed in detail.

1986 ◽  
Vol 32 (1) ◽  
pp. 73-78
Author(s):  
L. A. Cañas ◽  
M. Santaolalla

A new bacteriophage was found growing on Pseudomonas syringae pv. savastanoi isolates from knots of diseased Spanish olive trees. The bacteriophage had a contractile tail (type A1 of Bradley's classification: Myoviridae) of 60 × 14 nm and an icosahedral head (diameter, 45 nm) which contains DNA. Lipopolysaccharide from the outer membrane of the host bacteria was found to be the specific receptor for the bacteriophage. Phage inactivation was measured as a percentage decrease in plaque-forming units and by electron microscopy. This lipopolysaccharide showed an ultrastructure and chemical composition very similar to those obtained from other Gram-negative pathogenic bacteria. Mild hydrolysis of the lipopolysaccharide with 1% acetic acid liberated the carbohydrate moiety (degraded polysaccharide) from the lipid A. After hydrolysis, monosaccharides and fatty acids were studied by gas–liquid chromatography. The polysaccharide was mainly composed of rhamnose, glucose, and 2-keto-3-deoxyoctulosonic acid; the lipid A contained glucosamine, phosphate, and fatty acids, both hydroxylated (3-OH 10:0, 2-OH 12:0, and 3-OH 12:0) and nonhydroxylated (12:0, 16:1, and 16:0).


1973 ◽  
Vol 19 (2) ◽  
pp. 241-245 ◽  
Author(s):  
Carl F. Deneke ◽  
R. R. Colwell

Components of the cell envelope of Vibrio parahaemolyticus were investigated. Vibrio parahaemolyticus is an estuarine microorganism associated with diseases of marine and estuarine animals and seafood-borne enteritis in man. Purified lipopolysaccharide (LPS), isolated using a 45% phenol extraction procedure, was found to contain lipid A fraction to 27% of the LPS by weight. In the lipid A fraction, glucosamine was the only amino sugar to be present and a high molar ratio of phosphate to amino sugar (2.5:1) was noted. Two hydroxy fatty acids, hydroxydodecanoic and hydroxymyristic, were identified among the fatty acids by gas–liquid chromatography. A role of the lipopolysaccharides in the salt requirement of marine bacteria is suggested.


1975 ◽  
Vol 53 (5) ◽  
pp. 623-629 ◽  
Author(s):  
Malcolm B. Perry ◽  
Virginia Daoust ◽  
Benito B. Diena ◽  
Fraser E. Ashton ◽  
Rebecca Wallace

The lipopolysaccharides (LPS) of strains of Neisseria gonorrhoeae grown in type 1 (T1) and 4 (T4) colony forms have been isolated. LPS from T4 colony type cells on mild hydrolysis gave a lipid A and a core oligosaccharide composed of 2-amino-2-deoxy-D-glucose, D-glucose, D-galactose, L-glycero-D-manno-heptose and 3-deoxy-D-manno-octulosonic acid that appeared to be common to all the strains examined. LPS from T1 colony type cells on mild hydrolysis gave a lipid A and high molecular weight O polysaccharides which showed considerable differences in glycose composition for each strain examined. In those strains examined, T4 cells appear to produce a common 'R' type LPS whereas T1 cells produce an 'S' type LPS with structurally different O polysaccharide structures which probably account for serologically differentiated strains of N. gonorrhoeae.


1971 ◽  
Vol 49 (2) ◽  
pp. 243-250 ◽  
Author(s):  
G. A. Adams

Lipopolysaccharide (LPS) prepared from Neisseria sicca in 1.5% yield contained D-glucose, D-glucosamine, D-galactosamine, 3-deoxyoctulosonic acid, protein, lipid A, and phosphate. The molecule was judged to be homogeneous as tested by free boundary electrophoresis. D-Galactosamine was associated exclusively with the polysaccharide portion of the molecule and was in fourfold excess of D-glucosamine. The latter hexosamine was primarily a constituent of the lipid A moiety in which it formed the backbone structure linked glycosidically 1 → 4. To this structure, fatty acids, principally β-hydroxymyristic acid and β-hydroxylauric acid, were linked along with phosphate groups. The D-glucosamine units in the polysaccharide portion of the LPS molecule were also attached by 1 → 4 glycosidic linkages. D-Galactosamine units did not survive the methylation procedures due presumably to the lack of acyl protecting groups on its amino groups. Methylation results showed that approximately one-third of the D-glucose units were nonreducing end groups, approximately one-third were linked α1 → 2, a small proportion was linked 1 → 4, and the remainder was branched through C-3, C-4, and C-6. Periodate oxidation results were in agreement with the structure proposed on the basis of the methylation data. The LPS of N. sicca was considerably simpler than that of N. perflava and lacked heptose, rhamnose, and ethanolamine components.


Author(s):  
Evgeny Vinogradov ◽  
Buko Lindner ◽  
Guntram Seltmann ◽  
Joanna Radziejewska-Lebrecht ◽  
Otto Holst

2007 ◽  
Vol 56 (11) ◽  
pp. 1440-1446 ◽  
Author(s):  
Yutaka Makimura ◽  
Yasuyuki Asai ◽  
Akiko Sugiyama ◽  
Tomohiko Ogawa

The chemical structure and immunobiological activities of Serratia marcescens lipid A, an active centre of LPS, were investigated. LPS preparations of S. marcescens were extracted using a hot phenol/water method, after which purified lipid A specimens were prepared by weak acid hydrolysis, followed by normal phase and gel filtration chromatographic separation. The lipid A structure was determined by MS to be a diglucosamine backbone with diphosphates and five C14 normal chain acyl groups, including two acyloxyacyl groups at the 2 and 3 positions of the non-reducing side. S. marcescens lipid A and Escherichia coli-type synthetic lipid A (compound 506) exhibited definite reactivity in Limulus amoebocyte lysate assays. The lethal toxicity of S. marcescens lipid A was nearly comparable to that of compound 506, and both induced nuclear factor-κB activation in murine cells via Toll-like receptor (TLR)4/MD-2 but not TLR2, as well as various inflammatory cytokines in peritoneal macrophages of C3H/HeN mice but not C3H/HeJ mice. Furthermore, S. marcescens lipid A induced nearly the same amounts of tumour necrosis factor alpha, interleukin-6, and nitric oxide production by the murine alveolar macrophage cell line MH-S as compared with compound 506. These results indicate that S. marcescens possesses a penta-acylated lipid A, which is nearly identical to E. coli lipid A in regard to biological activities, while it also may be a crucial virulence factor of the bacterium.


1987 ◽  
Vol 65 (1) ◽  
pp. 1-7 ◽  
Author(s):  
Malcolm B. Perry ◽  
Leann L. MacLean

The cellular lipopolysaccharide produced by Yersinia enterocolitica serotype O:5,27 was of the S-type and composed of an antigenic O-chain polysaccharide linked through a core oligosaccharide region, which in turn was linked through 3-deoxy-D-manno-octulonosyl units to a lipid A moiety. The O-chain polysaccharide was composed of equal molar amounts of L-rhamnose and D-xylulose. By partial hydrolysis, periodate oxidation, methylation, specific optical rotation, and 13C and 1H nuclear magnetic resonance studies, the structure of the O-chain was established as being a linear backbone of alternating 1,3-linked α-L-rhamnopyranosyl and β-L-rhamnopyranosyl units, to which 2,2-linked β-D-threo-pent-2-ulofuranoside (D-xylulofuranoside) units were present on every L-rhamnopyranosyl residue, as shown below.[Formula: see text]


2018 ◽  
Vol 127 (1D) ◽  
pp. 13
Author(s):  
Trần Thị Ái Luyến ◽  
Đỗ Thị Bích Thủy ◽  
Trần Thị Văn Thi ◽  
Phan Thị Thu Huyền

<p><strong>Abstract: </strong>The effects of carbohydrate sources in various concentration (2%, 3%, 4%, 5%, 6%) and fermentation conditions (such as initial cell density, temperature, pH and incubation time) on EPS synthesis of <em>Lactobacillus fermentum </em>MC3 were also studied. The results showed that adding different sugars (including glucose, lactose and sucrose) to culture medium significantly increased the EPS production. In comparison with other concentrations, EPS amounts were maximized in the medium supplemented with 4% (w/v) of sugars. The outcome was the highest for glucose, which was 178.207 mg/L, the obtained figures for lactose and for sucrose were 148.614 mg/L and 152.272 mg/L respectively. The results indicated that EPS production by <em>L. fermentum </em>MC3 reached the maximum values in the medium supplemented with 4% (w/v) glucose at 40<sup>0</sup>C, pH 6.0, initial cell density of 10<sup>6</sup>CFU/ml for 48 h cultivation with amount of 200.728 mg/L. By methylation analysis and gas–liquid chromatography–mass spectrometry (GLC–MS), the exopolysaccharide was found to be composed of D-mannose: D-glucose: D-galactose in a molar ratio of 1 : 0.74 : 0.09.</p>


Author(s):  
A. V. Sulimov ◽  
A. V. Ovcharova ◽  
G. M. Kravchenko ◽  
Yu. K. Sulimova

Objectives. Cyclic carbonates are important products of organic synthesis, which are widely used as solvents, catalysts, and reagents for the production of various compounds (in particular, urethane-containing polymers) by the non-isocyanate method. The process of carbamide alcoholysis with polybasic alcohols is a promising method for the synthesis of cyclic carbonates. The purpose of this study is to determine the reaction conditions for the interaction of propylene glycol with carbamide in the presence of zinc acetate as a catalyst.Methods. We conducted experiments to study the synthesis of propylene carbonate in a batch laboratory apparatus. Moreover, we analyzed the starting reagents and final products using gas–liquid chromatography.Results. We studied the synthesis of propylene carbonate by carbamide alcoholysis with propylene glycol in the presence of a catalyst (zinc acetate) by varying the following parameters: initial molar ratio of propylene glycol/carbamide = (0.5–5):1, synthesis temperature 130–190°С, reagent residence time in the reactor 0.5–4 h, and the catalyst amount in the reaction mixture 0–1.5 wt %.Conclusions. We determined the technological parameters of propylene carbonate synthesis in a batch reactor. Moreover, we showed that the process allowed the production of propylene carbonate with a sufficiently high yield of 80%—at the initial molar ratio of propylene glycol/ carbamide = 3:1, temperature 170°C, and residence time 2 h.


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