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D'Hauteville H, Khan S, Maskell DJ, Kussak A, Weintraub A, Mathison J, Ulevitch RJ, Wuscher N, Parsot C, Sansonetti PJ. Two msbB genes encoding maximal acylation of lipid A are required for invasive Shigella flexneri to mediate inflammatory rupture and destruction of the intestinal epithelium. JOURNAL OF IMMUNOLOGY (BALTIMORE, MD. : 1950) 2002; 168:5240-51. [PMID: 11994481 DOI: 10.4049/jimmunol.168.10.5240] [Citation(s) in RCA: 105] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
Shigella flexneri is a Gram-negative pathogen that invades and causes inflammatory destruction of the human colonic epithelium, thus leading to bloody diarrhea and dysentery. A type III secretion system that delivers effector proteins into target eukaryotic cells is largely responsible for cell and tissue invasion. However, the respective role of this invasive phenotype and of lipid A, the endotoxin of the Shigella LPS, in eliciting the inflammatory cascade that leads to rupture and destruction of the epithelial barrier, was unknown. We investigated whether genetic detoxification of lipid A would cause significant alteration in pathogenicity. We showed that S. flexneri has two functional msbB genes, one carried by the chromosome (msbB1) and the other by the virulence plasmid (msbB2), the products of which act in complement to produce full acyl-oxy-acylation of the myristate at the 3' position of the lipid A glucosamine disaccharide. A mutant in which both the msbB1 and msbB2 genes have been inactivated was impaired in its capacity to cause TNF-alpha production by human monocytes and to cause rupture and inflammatory destruction of the epithelial barrier in the rabbit ligated intestinal loop model of shigellosis, indicating that lipid A plays a significant role in aggravating inflammation that eventually destroys the intestinal barrier. In addition, neutralization of TNF-alpha during invasion by the wild-type strain strongly impaired its ability to cause rupture and inflammatory destruction of the epithelial lining, thus indicating that TNF-alpha is a major effector of epithelial destruction by Shigella.
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Meister PD, Peterson DH, Eppstein SH, Murray HC, Reineke LM, Weintraub A, Osborn HML. Microbiological Transformations of Steroids. XI. The Transformation of 3-Ketobisnor-4-cholen-22-al to 11α,22-Dihydroxybisnor-4-cholen-3-one and 6β,11α,22-Trihydroxybisnor-4-cholen-3-one by Rhizopus1. J Am Chem Soc 2002. [DOI: 10.1021/ja01651a022] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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103
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Meister PD, Reineke LM, Meeks RC, Murray HC, Eppstein SH, Osborn HML, Weintraub A, Peterson DH. MICROBIOLOGICAL TRANSFORMATIONS OF STEROIDS. XII.1 17α-HYDROXYLATION. J Am Chem Soc 2002. [DOI: 10.1021/ja01644a073] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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104
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Peterson DH, Nathan AH, Meister PD, Eppstein SH, Murray HC, Weintraub A, Reineke LM, Leigh HM. Microbiological Transformations of Steroids. VI. Preparation of 11α-Hydroxy-6-dehydroprogesterone. J Am Chem Soc 2002. [DOI: 10.1021/ja01098a047] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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105
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Eppstein SH, Meister PD, Peterson DH, Murray HC, Osborn HML, Weintraub A, Reineke LM, Meeks RC. Microbiological Transformations of Steroids. XV. Tertiary Hydroxylation of Steroids by Fungi of the Order Mucorales1,2. J Am Chem Soc 2002. [DOI: 10.1021/ja01546a047] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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106
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Eppstein SH, Meister PD, Leigh HM, Peterson DH, Murray HC, Reineke LM, Weintraub A. Microbiological Transformations of Steroids.1 X. The Oxygenation of Androgens by Rhizopus2. J Am Chem Soc 2002. [DOI: 10.1021/ja01641a019] [Citation(s) in RCA: 37] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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107
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Peterson DH, Murray HC, Eppstein SH, Reineke LM, Weintraub A, Meister PD, Leigh HM. Microbiological Transformations of Steroids.1 I. Introduction of Oxygen at Carbon-11 of Progesterone. J Am Chem Soc 2002. [DOI: 10.1021/ja01143a033] [Citation(s) in RCA: 170] [Impact Index Per Article: 7.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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108
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Pederson RL, Campbell JA, Babcock JC, Eppstein SH, Murray HC, Weintraub A, Meeks RC, Meister PD, Reineke LM, Peterson DH. MICROBIOLOGICAL TRANSFORMATIONS OF STEROIDS. XIV.1 THE PREPARATION OF A TERTIARY HYDROXY-STEROID, 10ξ-HYDROXY-19-NORTESTOSTERONE. J Am Chem Soc 2002. [DOI: 10.1021/ja01588a068] [Citation(s) in RCA: 34] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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109
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Peterson DH, Meister PD, Weintraub A, Reineke LM, Eppstein SH, Murray HC, Osborn HML. Microbiological Transformation of Steroids. XIII. Oxygenation of 16α, 17α-Oxidoprogesterone to 11α-Hydroxy-16α, 17α-oxidoprogesterone by Rhizopus Nigricans Ehrb. (A.T.C.C. 6227b)1. J Am Chem Soc 2002. [DOI: 10.1021/ja01621a083] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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110
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Peterson DH, Eppstein SH, Meister PD, Magerlein BJ, Murray HC, Leigh HM, Weintraub A, Reineke LM. Microbiological Transformations of Steroids. IV. The 11-Epimer of Compound F and Other New Oxygenated Derivatives of Reichstein's Compound S. A New Route to Cortisone1. J Am Chem Soc 2002. [DOI: 10.1021/ja01098a045] [Citation(s) in RCA: 39] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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111
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Meister PD, Peterson DH, Murray HC, Eppstein SH, Reineke LM, Weintraub A, Leigh HM. Microbiological Transformations of Steroids. II. The Preparation of 11 α-Hydroxy- 17 α-progesterone. J Am Chem Soc 2002. [DOI: 10.1021/ja01097a015] [Citation(s) in RCA: 26] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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112
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Eppstein SH, Peterson DH, Leigh HM, Murray HC, Weintraub A, Reineke LM, Meister PD. Microbiological Transformations of Steroids. VII. Preparation of 11α-Hydroxypregnane-3,20-dione and 11α-Hydroxyallopregnane-3,20-dione1. J Am Chem Soc 2002. [DOI: 10.1021/ja01098a048] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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113
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Peterson DH, Eppstein SH, Meister PD, Murray HC, Leigh HM, Weintraub A, Reineke LM. MICROBIOLOGICAL TRANSFORMATIONS OF STEROIDS. IX. DEGRADATION OF C21 STEROIDS TO C19 KETONES AND TO TESTOLOLACTONE. J Am Chem Soc 2002. [DOI: 10.1021/ja01118a534] [Citation(s) in RCA: 70] [Impact Index Per Article: 3.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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114
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Meister PD, Peterson DH, Murray HC, Spero GB, Eppstein SH, Weintraub A, Reineke LM, Leigh HM. Microbiological Transformations of Steroids. V. The Oxygenation of 17α-Hydroxyprogesterone to 6β,17α-Dihydroxyprogesterone and 11α,17α-Dihydroxyprogesterone1. J Am Chem Soc 2002. [DOI: 10.1021/ja01098a046] [Citation(s) in RCA: 19] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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115
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Eppstein SH, Meister PD, Peterson DH, Murray HC, Leigh HM, Lyttle DA, Reineke LM, Weintraub A. Microbiological Transformations of Steroids. III.1 Preparation of 11-Epi-corticosterone and of 6β-Hydroxy-11-desoxycorticosterone. J Am Chem Soc 2002. [DOI: 10.1021/ja01098a044] [Citation(s) in RCA: 32] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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116
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Bergström N, Nair GB, Weintraub A, Jansson PE. Structure of the O-polysaccharide from the lipopolysaccharide from Vibrio cholerae O6. Carbohydr Res 2002; 337:813-7. [PMID: 11996834 DOI: 10.1016/s0008-6215(02)00056-3] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
The O-polysaccharide from Vibrio cholerae O6 was isolated from the LPS by mild-acid hydrolysis and has been investigated by sugar and methylation analysis and NMR spectroscopy. The polysaccharide was also depolymerized with aqueous hydrofluoric acid to give the repeating unit and multiples thereof. The O-polysaccharide had the following tetrasaccharide repeating unit. Two O-acetyl groups are present, one of them making the GlcNAc residue fully substituted and the steric crowding considerable at the branching residue.
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Petropoulos VC, Weintraub A, Weintraub GS. The dental student as a technician: preclinical and clinical laboratory programs in fixed prosthodontics. J Prosthodont 2001; 10:164-9. [PMID: 11641845 DOI: 10.1111/j.1532-849x.2001.00164.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
PURPOSE A 2-part survey of United States dental schools was conducted. The first part of the survey was published in 1998 and determined the curricular structure, techniques taught, and materials used in predoctoral fixed prosthodontics courses. The purpose of the second part of the survey was to ascertain the delegation of laboratory procedures in preclinical and clinical fixed prosthodontic programs. MATERIALS AND METHODS The survey was mailed to the course directors of predoctoral fixed prosthodontic programs at 53 US dental schools. Of these, 42 schools returned the completed survey, resulting in a response rate of 79%. RESULTS Results from this survey show that certain laboratory procedures in preclinical and clinical fixed prosthodontics are completed by dental laboratories (either in-house or commercially available laboratories). CONCLUSIONS For the preclinical programs of fixed prosthodontics, there is more student involvement in the completion of laboratory procedures in the dental schools surveyed. In clinical fixed prosthodontic programs, there is a high emphasis on patient care and less on laboratory techniques that can be delegated to laboratory technicians.
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118
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Linnerborg M, Weintraub A, Albert MJ, Widmalm G. Depolymerization of the capsular polysaccharide from Vibrio cholerae O139 by a lyase associated with the bacteriophage JA1. Carbohydr Res 2001; 333:263-9. [PMID: 11454333 DOI: 10.1016/s0008-6215(01)00159-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
We have studied the interaction between the Vibrio cholerae O139 specific phage JA1, belonging to the Podoviridae family, and the capsular polysaccharide (CPS) of the parent strain from which the phage was isolated. Upon incubation of the JA1 phage with the CPS, oligosaccharides were isolated and purified. The oligosaccharides derived from one (shown below) and two repeating units of the CPS were characterized using NMR spectroscopy, mass spectrometry and sugar analysis (structure: see text). The cleavage was found to occur by beta-elimination at the 4-substituted alpha-linked galacturonic acid, which results in a 4-deoxy-beta-L-threo-hex-4-enopyranosyl uronic acid group (Sug). The enzyme associated with the JA1 phage responsible for the depolymerization of the V. cholerae O139 CPS is thus a lyase.
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119
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Yildirim H, Weintraub A, Widmalm G. Structural studies of the O-polysaccharide from the Escherichia coli O77 lipopolysaccharide. Carbohydr Res 2001; 333:179-83. [PMID: 11448680 DOI: 10.1016/s0008-6215(01)00123-9] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The structure of the O-antigen polysaccharide (PS) from Escherichia coli O77 has been determined. Sugar and methylation analysis together with 1H and 13C NMR spectroscopy were the main methods used. The PS is composed of tetrasaccharide repeating units with the following structure:-->2)-alpha-D-Manp-(1-->2)-beta-D-Manp-(1-->3)-alpha-D-GlcpNAc-(1-->6)-alpha-D-Manp-(1-->
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120
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Kocharova NA, Knirel YA, Jansson P, Weintraub A. Structure of the O-specific polysaccharide of Vibrio cholerae O9 containing 2-acetamido-2-deoxy-d-galacturonic acid. Carbohydr Res 2001; 332:279-84. [PMID: 11376607 DOI: 10.1016/s0008-6215(01)00069-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Abstract
The O-specific polysaccharide (OPS) was isolated by mild-acid degradation of the lipopolysaccharide of Vibrio cholerae O9 and studied by carboxyl reduction, sugar and methylation analyses, Smith degradation, and two-dimensional NMR spectroscopy, including COSY, TOCSY, NOESY, and H-detected 1H,(13)C HMQC experiments. The following structure of the pentasaccharide-repeating unit of the OPS was established:
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121
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Baxa U, Cooper A, Weintraub A, Pfeil W, Seckler R. Enthalpic barriers to the hydrophobic binding of oligosaccharides to phage P22 tailspike protein. Biochemistry 2001; 40:5144-50. [PMID: 11318636 DOI: 10.1021/bi0020426] [Citation(s) in RCA: 24] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The structural thermodynamics of the recognition of complex carbohydrates by proteins are not well understood. The recognition of O-antigen polysaccharide by phage P22 tailspike protein is a highly suitable model for advancing knowledge in this field. The binding to octa- and dodecasaccharides derived from Salmonella enteritidis O-antigen was studied by isothermal titration calorimetry and stopped-flow spectrofluorimetry. At room temperature, the binding reaction is enthalpically driven with an unfavorable change in entropy. A large change of -1.8 +/- 0.2 kJ mol(-1) K(-1) in heat capacity suggests that the hydrophobic effect and water reorganization contribute substantially to complex formation. As expected from the large heat-capacity change, we found enthalpy-entropy compensation. The calorimetrically measured binding enthalpies were identical within error to van't Hoff enthalpies determined from fluorescence titrations. Binding kinetics were determined at temperatures ranging from 10 to 30 degrees C. The second-order association rate constant varied from 1 x 10(5) M(-1) s(-1) for dodecasaccharide at 10 degrees C to 7 x 10(5) M(-1) s(-1) for octasaccharide at 30 degrees C. The first-order dissociation rate constants ranged from 0.2 to 3.8 s(-1). The Arrhenius activation energies were close to 50 and 100 kJ mol(-1) for the association and dissociation reactions, respectively, indicating mainly enthalpic barriers. Despite the fact that this system is quite complex due to the flexibility of the saccharide, both the thermodynamic and kinetic data are compatible with a simple one-step binding model.
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122
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Coniglio SJ, Lewis JD, Lang C, Burns TG, Subhani-Siddique R, Weintraub A, Schub H, Holden EW. A randomized, double-blind, placebo-controlled trial of single-dose intravenous secretin as treatment for children with autism. J Pediatr 2001; 138:649-55. [PMID: 11343038 DOI: 10.1067/mpd.2001.112474] [Citation(s) in RCA: 44] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
Abstract
OBJECTIVE To determine whether a single injection of intravenous secretin results in measurable improvements in socialization and/or communication skills in children with autism. STUDY DESIGN Sixty subjects with autism were randomly selected and assigned to either treatment or placebo group. Subjects in the treatment group received 2.0 clinical units of secretin per kilogram of body weight as a single intravenous dose. Subjects in the placebo group received normal saline solution. Neurodevelopmental and behavioral assessments were performed for all subjects before injection and at 3 and 6 weeks after injection. RESULTS Assessment of language skills and parents' behavioral assessments revealed no significant differences between the treatment and placebo groups. Raters' assessments of severity of autistic symptoms did not differ for the 2 groups at 6 weeks after injection. A marginally statistically significant improvement in autistic behaviors was seen in the treatment group at 3 weeks after injection (P =.051). CONCLUSIONS A single dose of intravenous secretin does not appear to have significant effects on either parents' perception of autistic behaviors or language skills at 6 weeks after injection. Transient, marginally significant improvements in autistic behaviors may occur in some children.
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123
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Landersjö C, Weintraub A, Widmalm G. Structural analysis of the O-antigen polysaccharide from the Shiga toxin-producing Escherichia coli O172. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:2239-45. [PMID: 11298740 DOI: 10.1046/j.1432-1327.2001.02095.x] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
The structure of the O-antigen polysaccharide from Escherichia coli O172 has been determined. In combination with sugar analysis, NMR spectroscopy shows that the polysaccharide is composed of pentasaccharide repeating units. Sequential information was obtained by mass spectrometry and two-dimensional NMR techniques. An O-acetyl group was present as 0.7 equivalent per repeating unit. Treatment of the O-deacetylated polysaccharide with aqueous 48% hydrofluoric acid rendered cleavage of the phosphodiester in the backbone of the polymer and the pentasaccharide isolated after gel permeation chromatography was structurally characterized. Subsequent NMR experiments on polymeric materials revealed the structure of the repeating unit of the O-polysaccharide from E. coli O172 as:-->P-4)-alpha-D-Glcp-(1-->3)-alpha-L-FucpNAc-(1-->3)-alpha-D- GlcpNAc-(1-->3)-alpha-L-FucpNAc-(1-->4)-alpha-D-Glcp6Ac-(1-->
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Kaca W, Literacka E, Sjöholm AG, Weintraub A. Complement activation by Proteus mirabilis negatively charged lipopolysaccharides. JOURNAL OF ENDOTOXIN RESEARCH 2001; 6:223-34. [PMID: 11052177] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Proteus mirabilis strains are human pathogens responsible for urinary tract infections and bacteremias and may be involved in rheumatoid arthritis. Lipopolysaccharide (LPS, bacterial endotoxin), the major component of the cell wall, is one of the virulence factors of Proteus. In the presented studies, we have investigated complement activation by LPSs isolated from P. mirabilis O10, O23, O30, and O43 strains, which differ in the number of negative COO- groups on their polysaccharide components. Four P. mirabilis strains studied were sensitive to complement-mediated killing, despite complement binding by their LPSs. The optimal complement binding by LPSs was detected in serum with functional assays for both the classical and alternative pathways. Complement activation in 80% serum by the smooth, uronic acid, and hexosamine containing P. mirabilis LPSs was not critically determined by the structure of their O-chain polysaccharides. One of four LPSs used as a model, P. mirabilis O10 LPS, fragmented C3 in an LPS dose- and time-dependent manner. It was detected by crossed-immunoelectrophoresis and capture ELISA with anti-C3c antibodies. The lower complement activation by 023 LPS correlates with its reduced C3 fragmentation, compared with three other Proteus LPSs studied. Rabbit anti-O antibodies enhanced the complement binding and factor C3 fragmentation by O10, O23, O30, and O43 P. mirabilis LPSs.
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125
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Kocharova NA, Perepelov AV, Zatonsky GV, Shashkov AS, Knirel YA, Jansson PE, Weintraub A. Structural studies of the O-specific polysaccharide of Vibrio cholerae O8 using solvolysis with triflic acid. Carbohydr Res 2001; 330:83-92. [PMID: 11217966 DOI: 10.1016/s0008-6215(00)00271-8] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/18/2022]
Abstract
The O-specific polysaccharide (OPS) of Vibrio cholerae 08 was isolated by mild acid degradation of the lipopolysaccharide and studied by two-dimensional NMR spectroscopy, including NOESY and heteronuclear multiple-bond correlation (HMBC) experiments. The OPS was found to have a tetrasaccharide repeating unit with the following structure: --> 4)-beta-D-Glcp NAc3NAcylAN-(1 --> 4)-beta-D-Manp NAc3NAcAN-(1 --> 4)-alpha-L-Gulp NAc3NAcA-(1 --> 3) -beta-D-QuipNAc4NAc-(1 --> where QuiNAc4NAc is 2,4-diacetamido-2,4,6-trideoxyglucose, GlcNAc3NAcylAN is 2-acetamido-3-(N-formyl-L-alanyl)amino-2,3-dideoxyglucuronamide, ManNAc3NAcAN is 2,3-diacetamido-2,3-dideoxymannuronamide, and GulNAc3NAcA is 2,3-diacetamido-2,3-dideoxyguluronic acid. The OPS was stable towards acid hydrolysis and solvolysis with anhydrous hydrogen fluoride, but could be cleaved selectively with trifluoromethanesulfonic (triflic) acid by the glycosidic linkages of beta-QuiNAc4NAc and alpha-GulNAc3NAcA. The structures of the oligosaccharides obtained that were elucidated by electrospray ionization (ESI) MS and NMR spectroscopy, confirmed the OPS structure.
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