Unique cholesteryl glucosides in Helicobacter pylori: composition and structural analysis (original) (raw)
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FEMS Microbiology Letters, 2005
The presence of cholesteryl glucosides and high levels of lysophospholipids are elements making the cell wall of Helicobacter pylori unique. In this study, we have investigated the relationship between lysophospholipid content and cholesteryl glucoside composition of variants of 6 clinical isolates. The samples were characterized by diverse outer membrane phospholipase A activity measured as lysophospholipid content of the cell wall. A pldA negative mutant was also included in the study. Thin-layer chromatography showed that cholesteryl glucosides were present in all samples. However, the distribution of cholesteryl-6-O-acyl-a-D Dglucopyranoside, cholesteryl-a-D D-glucopyranoside and cholesteryl-6-O-phosphatidyl-a-D D-glucopyranoside varied according to ysophospholipid content. Cholesteryl-6-O-acyl-a-D D-glucopyranoside was exclusively observed in the isolates/variants with an intact pldA and where a significant amount of lysophospholipids could be demonstrated. High lysophospholipid content destabilizes membranes. The balance between cholesteryl-6-O-acyl-a-D D-glucopyranoside, cholesteryl-a-D D-glucopyranoside and cholesteryl-6-O-phosphatidyl-a-D D-glucopyranoside in H. pylori is probably important for the stability of the membrane when the lysophospholipid content varies.
Acta medica Okayama, 1995
Many of Helicobacter species have been found to have novel cholesteryl glucosides (CGs). To study the biosynthetic mechanism of CGs, the lipid profiles of H. pylori and H. mustelae grown in serum-supplemented and cholesterol-restricted serum-free media were investigated. In contrast to the serum-supplemented state, helicobacters had less CGs in the serum-free state; a trace amount of CGs and no CG was detected in H. pylori and H. mustelae, respectively. The proportion of total and individual phospholipid also showed significant alteration. Unknown lipids which did not contain phosphate and sugar were detected in the serum-free state, but not in the serum-supplemented state. The CGs were found to be distributed mainly in the membrane fractions, and one of the unknown lipids was found exclusively in the cytosol fraction. Based on these data, it is apparent that the CGs of helicobacters are synthesized by de novo uptake of cholesterol from the media. The unknown lipids detected in the ...
Lipid profile of Helicobacter spp.: presence of cholesteryl glucoside as a characteristic feature
Journal of bacteriology, 1996
The lipid and fatty acid profiles of eight Helicobacter spp. (H. nemestrinae, H. acinonyx, H. canis, Helicobacter sp. strain CLO-3, "H. rappini" [Flexispira rappini], H. pametensis, Helicobacter sp. strain Bird-B, and Helicobacter sp. strain Bird-C) and the fatty acid profiles of five additional species (H. pylori, H. felis, H. muridarum, H. mustelae, and H. fennelliae) were analyzed and compared. A heterologous fatty acid profile was observed among the Helicobacter spp., and on that basis the species could be divided into two groups. Group A had 19-carbon cyclopropane fatty acid (19:0cyc) and tetradecanoic acid (14:0) as the major fatty acids, and group B characteristically lacked the 19:0cyc and had hexadecanoic acid (16:0) and octadecenoic (18:1) acids as the major fatty acids. The species of group A are primarily gastric colonizers, and those of group B are primarily intestinal colonizers. Seven of the eight species studied showed the unusual and characteristic presenc...
2014
Steryl glycosides produced by bacteria play important biological roles in the evasion and modulation of host immunity. Step-economical syntheses of three cholesteryl-6-O-phosphatidyl-α-D-glucopyranosides (αCPG) unique to Helicobacter pylori have been achieved. The approach relies upon regioselective deprotection of per-O-trimethylsilyl-α-D-cholesterylglucoside at C6 followed by phosphoramidite coupling. Global TMS ether deprotection in the presence of oxygen and subsequent deprotection of the cyano ethyl phosphoester afforded the target compounds in 16-21 % overall yield starting from D-glucose. The structures of these natural products were determined using a combination of 2D NMR methods and mass spectrometry. These robust synthesis and characterization protocols provide analogues to facilitate glycolipidomic profiling and biological studies.
Helicobacter mustelae lipid A structure differs from that of Helicobacter pylori
FEBS Letters, 2001
The lipid A structure of the Gram-negative bacterium Helicobacter mustelae, a ferret gastric pathogen responsible for the onset of gastric diseases in its host, was investigated. Two variant lipid A structures were found in the same strain. One structure contained a bisphosphorylated L L-(1C C6)-linked Dglucosamine backbone disaccharide with hydroxytetradecanoic acid in amide linkages. Unlike the structure described for the lipid A of the related human Helicobacter pylori gastric pathogen, which contains a C1 phosphate moiety, this lipid A presented phosphate groups at both the C1 and C4P P positions, and contained no octadecanoyl fatty acid, which is present in H. pylori. The second lipid A structure had a different fatty acid composition in that 3-OH C 16 replaced most of the amide-linked 3-OH C 14 . ß 2001 Federation of European Biochemical Societies. Published by Elsevier Science B.V. All rights reserved.
Steryl glycosides: a characteristic feature of the Helicobacter spp.?
Journal of Bacteriology, 1995
The lipids of different species of Helicobacter (H.felis, H. muridarum, H. mustelae, H. fennelliae, and H. cinaedi) were studied. Different types of cholesteryl glucosides were found in all of the species studied except H. cinaedi. The total amount of cholesteryl glucosides varied from 14.8% of total lipids in H. mustelae to 33.1% of total lipids in H. felis. The different types of cholesteryl glucosides and their species distribution are cholesteryl-6-O-acyl-alpha-D-glucopyranoside (cholesteryl-6-O-tetradecanoyl-alpha-D-glucopyranoside in H. felis and cholesteryl-6-O-dodecanoyl-alpha-D-glucopyranoside in H. muridarum), cholesteryl-alpha-D-glucopyranoside (H. felis, H. muridarum, H. mustelae, and H. fennelliae), and cholesteryl-6-O-phosphatidyl-alpha-D-glucopyranoside (H. fennelliae). The neutral lipid fractions showed a high percentage of cholesterol, with selective accumulation of free cholesterol. The study thus shows that the characteristic presence of steryl glycosides in Helic...
Lipid composition and fatty acid analysis ofHelicobacter pylori
Journal of Gastroenterology, 1995
Lipids extracted from Helicobacter pylori were separated into lipid classes by thin-layer chromatography. Simple H. pylori lipids consisted of cholesterol esters, triglycerides, free fatty acids, cholesterol, diacylglycerols, and monoacylglycerols. Fatty acids were released from each lipid class by acid methanolysis, and analyzed by gas liquid chromatography and mass spectrometry. Unique methoxy fatty acids, including l l-methoxy heptadecanoic and l lmethoxy nonadecanoic acids, were the major components of the cholesterol esters and triglycerides. The predominance of methoxy fatty acids in the cholesterol esters of H. pylori may contribute to the acid-resistant characteristic of this bacillus.
Compositional analysis of Helicobacter pylori rough-form lipopolysaccharides
Journal of Bacteriology, 1992
Sodium dodecyl sulfate-polyacrylamide gel electrophoresis was used to analyze the macromolecular heterogeneity of lipopolysaccharides (LPS) from seven fresh clinical isolates and three culture collection strains of the human pathogen Helicobacter pylori. All the clinical isolates produced smooth-form LPS with O side chains of relatively homogeneous chain length, whereas the culture collection strains yielded rough-form LPS. A better yield of the latter LPS was obtained when combined protease pretreatment and hot phenol-water extraction were used than when the conventional phenol-water technique alone was used for extraction. The LPS of the three culture collection strains (S-24, C-5437, and NCTC 11637) were chemically characterized. Constituents common to all the LPS were fucose, D-mannose, D-glucose, D-galactose, D-glycero-D-manno-heptose, L-glycero-D-manno-heptose, and 3-deoxy-D-manno-2-octulosonic acid. The molar ratios of the hexoses differed between different strains, thereby r...
Carbohydrate Research, 2011
We describe a re-investigation of the structure of the lipopolysaccharide (LPS) from Helicobacter pylori genomic strain 26695 and its corresponding HP0826::Kan mutant lacking the O-chain component based on the in-depth NMR analysis of the oligosaccharide products obtained through the use of various degradation procedures performed on the purified LPS from both strains, as well as CE-MS data. New structural evidence indicates the presence of the linear arrangement of glucan and heptan portions of the LPS attached through -6-a-DDHep-3-a-L-Fuc-3-b-GlcNAc-fragment to the inner core DD-heptose residue. This structure differs from previously reported structures of the H. pylori 26695 LPS in several aspects. Crown
A reinvestigation of the lipopolysaccharide structure of Helicobacter pylori strain Sydney (SS1)
FEBS Journal, 2011
R R ¼ PS-2-b-Ribf -½2-b-Ribfn -4-b-Gal-3-a-Glc-7-a-DDHep-3-a-L-Fuc-3-b-GlcNwhere [2-b-Ribf-] n is a short (three to five residues) oligomer of 1,2-linked b-ribofuranose (riban), and PS is a polysaccharide chain consisting of N-acetyllactosamine, substituted with a-Fuc to form Lewis (Le)-type structures. In addition to the previously identified LacNAc, Le y and Le x components, the O-chain polysaccharide of H. pylori SS1 LPS was found to contain a novel LacNAc unit carrying a phosphoethanolamine substituent at the O-6 position of b-GlcNAc residues.