tailieunhanh - Báo cáo khoa học: Endotoxic activity and chemical structure of lipopolysaccharides from Chlamydia trachomatis serotypes E and L2 and Chlamydophila psittaci 6BC

The lipopolysaccharide (LPS) ofChlamydia trachomatis serotype E was isolated from tissue culture-grown element-ary bodies and analyzed structurally by mass spectrometry and 1 H, 13 Cand31 P nuclear magnetic resonance. The LPS is composed of the same pentasaccharide bisphosphate aKdo-(2–8)-aKdo-(2–4)-aKdo-(2–6)-bGlcN-4P-(1–6)-aGlcN-1P (Kdo is 3-deoxy-a-D-manno-oct-2-ulosonic acid) as reported forC. trachomatisserotype L2[Rund,S.,Lind-ner,B.,Brade,H. and Holst,O. (1999)J. Biol. , 16819–16824]. The glucosamine disaccharide backbone is substituted with a complex mixture of fatty acids with ester or amide linkage whereby no ester-linked hydroxy fatty acids were found. . | Eur. J. Biochem. 270 44 40 2003 FEBS 2003 doi Endotoxic activity and chemical structure of lipopolysaccharides from Chlamydia trachomatis serotypes E and L2 and Chlamydophila psittaci 6BC Holger Heine Sven Miiller-Loennies Lore Brade Buko Lindner and Helmut Brade Research Center Borstel Center for Medicine and Biosciences Borstel Germany The lipopolysaccharide LPS of Chlamydia trachomatis serotype E was isolated from tissue culture-grown elementary bodies and analyzed structurally by mass spectrometry and 1H 13C and 31P nuclear magnetic resonance. The LPS is composed of the same pentasaccharide bisphosphate aKdo- 2-8 -aKdo- 2-4 -aKdo- 2-6 -pGlcN-4P- 1-6 -aGlcN-1P Kdo is 3-deoxy-a-D-manno-oct-2-ulosonic acid as reported for C. trachomatis serotype L2 Rund s. 1011--ner B Bidde. H. and Holst o. 1SW J. Biol. Chem. 274 16819-16824 . The glucosamine disaccharide backbone is substituted with a complex mixture of fatty acids with ester or amide linkage whereby no ester-linked hydroxy fatty acids were found. The LPS was purified carefully with contaminations by protein or nucleic acids below and tested for its ability to induce proinflammatory cytokines in several readout systems in comparison to LPS from C. trachomatis serotype L2 and Chlamydophila psittaci strain 6BC as well as enterobacterial smooth and rough LPS and synthetic hexaacyl lipid A. The chlamydial LPS were at least 10 times less active than typical endotoxins specificity of the activities was confirmed by inhibition with the LPS antagonist B123o or with monodontd iuitdiodiess anninst chlamydial LPS. Like other LPS the clflamydial LPS ueed toll-like receptor TLR4 for signalling hut uniike other L I S activation was strictly CD14-dependent. Keywords toll-like receptors innate immunity MALDI-tOf MS ESI-FT-IR Ms. Chlamydia are obligatory intracellular bacteria 1 causing acute and chronic infections in animals and humans 2 3 . Little is known about the pathogenic mechanisms .