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Pesquisa : D08.811.520.241.700.350.500 [Categoria DeCS]
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[PMID]:27193154
[Au] Autor:Penttinen R; Kinnula H; Lipponen A; Bamford JK; Sundberg LR
[Ad] Endereço:Department of Biological and Environmental Science and Nanoscience Center, University of Jyvaskyla, Center of Excellence in Biological Interactions, P.O. Box 35, FI-40014, University of Jyvaskyla, Jyvaskyla, Finland. reetta.k.penttinen@jyu.fi.
[Ti] Título:High Nutrient Concentration Can Induce Virulence Factor Expression and Cause Higher Virulence in an Environmentally Transmitted Pathogen.
[So] Source:Microb Ecol;72(4):955-964, 2016 11.
[Is] ISSN:1432-184X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Environmentally transmitted opportunistic pathogens shuttle between two substantially different environments: outside-host and within-host habitats. These environments differ from each other especially with respect to nutrient availability. Consequently, the pathogens are required to regulate their behavior in response to environmental cues in order to survive, but how nutrients control the virulence in opportunistic pathogens is still poorly understood. In this study, we examined how nutrient level in the outside-host environment affects the gene expression of putative virulence factors of the opportunistic fish pathogen Flavobacterium columnare. The impact of environmental nutrient concentration on bacterial virulence was explored by cultivating the bacteria in various nutrient conditions, measuring the gene expression of putative virulence factors with RT-qPCR and, finally, experimentally challenging rainbow trout (Oncorhynchus mykiss) fry with these bacteria. Our results show that increased environmental nutrient concentration can increase the expression of putative virulence genes, chondroitinase (cslA) and collagenase, in the outside-host environment and may lead to more rapid fish mortality. These findings address that the environmental nutrients may act as significant triggers of virulence gene expression and therefore contribute to the interaction between an environmentally transmitted opportunistic pathogen and its host.
[Mh] Termos MeSH primário: Condroitina Liases/metabolismo
Colagenases/metabolismo
Doenças dos Peixes/microbiologia
Flavobacterium/patogenicidade
Oncorhynchus mykiss/microbiologia
Fatores de Virulência/metabolismo
[Mh] Termos MeSH secundário: Animais
Condroitina Liases/genética
Colagenases/genética
Exposição Ambiental
Alimentos
Reação em Cadeia da Polimerase em Tempo Real
Microbiologia da Água
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Virulence Factors); EC 3.4.24.- (Collagenases); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:171107
[Lr] Data última revisão:
171107
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160520
[St] Status:MEDLINE


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[PMID]:27083825
[Au] Autor:Wu J; Ji Y; Su N; Li Y; Liu X; Mei X; Zhou Q; Zhang C; Xing XH
[Ad] Endereço:Key Laboratory for Industrial Biocatalysis, Ministry of Education, Institute of Biochemical Engineering, Department of Chemical Engineering, Tsinghua University, Beijing 100084, People's Republic of China; Product Research and Development Center, Yichang Humanwell Pharmaceutical Co., Ltd., No.19, Da
[Ti] Título:Establishment of chondroitin B lyase-based analytical methods for sensitive and quantitative detection of dermatan sulfate in heparin.
[So] Source:Carbohydr Polym;144:338-45, 2016 Jun 25.
[Is] ISSN:1879-1344
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Dermatan sulfate (DS) is one of the hardest impurities to remove from heparin products due to their high structural similarity. The development of a sensitive and feasible method for quantitative detection of DS in heparin is essential to ensure the clinical safety of heparin pharmaceuticals. In the current study, based on the substrate specificity of chondroitin B lyase, ultraviolet spectrophotometric and strong anion-exchange high-performance liquid chromatographic methods were established for detection of DS in heparin. The former method facilitated analysis in heparin with DS concentrations greater than 0.1mgmL(-1) at 232nm, with good linearity, precision and recovery. The latter method allowed sensitive and accurate detection of DS at concentrations lower than 0.1mgmL(-1), exhibiting good linearity, precision and recovery. The linear range of DS detection using the latter method was between 0.01 and 0.5mgmL(-1).
[Mh] Termos MeSH primário: Condroitina Liases/metabolismo
Cromatografia Líquida de Alta Pressão/métodos
Dermatan Sulfato/análise
Heparina/química
Espectrofotometria Ultravioleta/métodos
[Mh] Termos MeSH secundário: Dissacarídeos/análise
Troca Iônica
Limite de Detecção
Modelos Lineares
Polimerização
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Disaccharides); 24967-94-0 (Dermatan Sulfate); 9005-49-6 (Heparin); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1701
[Cu] Atualização por classe:170104
[Lr] Data última revisão:
170104
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160417
[St] Status:MEDLINE


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[PMID]:26986023
[Au] Autor:Takeda N; Horai S; Tamura J
[Ad] Endereço:Organization for Regional Industrial Academic Cooperation, Tottori University, 4-101 Koyamacho-Minami, Tottori 680-8550, Japan. Electronic address: ntakeda@rs.tottori-u.ac.jp.
[Ti] Título:Facile analysis of contents and compositions of the chondroitin sulfate/dermatan sulfate hybrid chain in shark and ray tissues.
[So] Source:Carbohydr Res;424:54-8, 2016 Apr 07.
[Is] ISSN:1873-426X
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:The chondroitin sulfate (CS)/dermatan sulfate (DS) hybrid chain was extracted from specific tissues of several kinds of sharks and rays. The contents and sulfation patterns of the CS/DS hybrid chain were precisely analyzed by digestion with chondroitinases ABC and AC. All samples predominantly contained the A- and C-units. Furthermore, all samples characteristically contained the D-unit. Species-specific differences were observed in the contents of the CS/DS hybrid chain, which were the highest in Mako and Blue sharks and Sharpspine skates, but were lower in Hammerhead sharks. Marked differences were observed in the ratio of the C-unit/A-unit between sharks and rays. The contents of the CS/DS hybrid chain and the ratio of the C-unit/A-unit may be related to an oxidative stress-decreasing ability.
[Mh] Termos MeSH primário: Sulfatos de Condroitina/química
Dermatan Sulfato/química
Estresse Oxidativo
[Mh] Termos MeSH secundário: Animais
Condroitina ABC Liase/química
Condroitina Liases/química
Tubarões
Raias
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
24967-94-0 (Dermatan Sulfate); 9007-28-7 (Chondroitin Sulfates); EC 4.2.2.- (Chondroitin Lyases); EC 4.2.2.20 (Chondroitin ABC Lyase)
[Em] Mês de entrada:1612
[Cu] Atualização por classe:161230
[Lr] Data última revisão:
161230
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160318
[St] Status:MEDLINE


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[PMID]:26742844
[Au] Autor:Yin FX; Wang FS; Sheng JZ
[Ad] Endereço:From the Key Laboratory of Chemical Biology of Natural Products (Ministry of Education), Institute of Biochemical and Biotechnological Drug, School of Pharmaceutical Sciences, Shandong University, Jinan 250012, China and.
[Ti] Título:Uncovering the Catalytic Direction of Chondroitin AC Exolyase: FROM THE REDUCING END TOWARDS THE NON-REDUCING END.
[So] Source:J Biol Chem;291(9):4399-406, 2016 Feb 26.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Glycosaminoglycans (GAGs) are polysaccharides that play vital functional roles in numerous biological processes, and compounds belonging to this class have been implicated in a wide variety of diseases. Chondroitin AC lyase (ChnAC) (EC 4.2.2.5) catalyzes the degradation of various GAGs, including chondroitin sulfate and hyaluronic acid, to give the corresponding disaccharides containing an Δ(4)-unsaturated uronic acid at their non-reducing terminus. ChnAC has been isolated from various bacteria and utilized as an enzymatic tool for study and evaluating the sequencing of GAGs. Despite its substrate specificity and the fact that its crystal structure has been determined to a high resolution, the direction in which ChnAC catalyzes the cleavage of oligosaccharides remain unclear. Herein, we have determined the structural cues of substrate depolymerization and the cleavage direction of ChnAC using model substrates and recombinant ChnAC protein. Several structurally defined oligosaccharides were synthesized using a chemoenzymatic approach and subsequently cleaved using ChnAC. The degradation products resulting from this process were determined by mass spectrometry. The results revealed that ChnAC cleaved the ß1,4-glycosidic linkages between glucuronic acid and glucosamine units when these bonds were located on the reducing end of the oligosaccharide. In contrast, the presence of a GlcNAc-α-1,4-GlcA unit at the reducing end of the oligosaccharide prevented ChnAC from cleaving the GalNAc-ß1,4-GlcA moiety located in the middle or at the non-reducing end of the chain. These interesting results therefore provide direct proof that ChnAC cleaves oligosaccharide substrates from their reducing end toward their non-reducing end. This conclusion will therefore enhance our collective understanding of the mode of action of ChnAC.
[Mh] Termos MeSH primário: Arthrobacter/enzimologia
Proteínas de Bactérias/metabolismo
Condroitina Liases/metabolismo
Oligossacarídeos/metabolismo
[Mh] Termos MeSH secundário: Resinas de Troca de Ânions
Proteínas de Bactérias/genética
Biocatálise
Sequência de Carboidratos
Condroitina Liases/genética
Cromatografia Líquida de Alta Pressão
Hidrólise
Oligossacarídeos/química
Proteínas Recombinantes/metabolismo
Espectrometria de Massas por Ionização por Electrospray
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anion Exchange Resins); 0 (Bacterial Proteins); 0 (Oligosaccharides); 0 (Recombinant Proteins); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1608
[Cu] Atualização por classe:170226
[Lr] Data última revisão:
170226
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:160109
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.C115.708396


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[PMID]:26253667
[Au] Autor:Li N; Qin T; Zhang XL; Huang B; Liu ZX; Xie HX; Zhang J; McBride MJ; Nie P
[Ad] Endereço:State Key Laboratory of Freshwater Ecology and Biotechnology, Institute of Hydrobiology, Chinese Academy of Sciences, Wuhan, Hubei Province, China.
[Ti] Título:Gene deletion strategy to examine the involvement of the two chondroitin lyases in Flavobacterium columnare virulence.
[So] Source:Appl Environ Microbiol;81(21):7394-402, 2015 Nov.
[Is] ISSN:1098-5336
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Flavobacterium columnare is an important bacterial pathogen of freshwater fish that causes high mortality of infected fish and heavy economic losses in aquaculture. The pathogenesis of this bacterium is poorly understood, in part due to the lack of efficient methods for genetic manipulation. In this study, a gene deletion strategy was developed and used to determine the relationship between the production of chondroitin lyases and virulence. The F. johnsoniae ompA promoter (PompA) was fused to sacB to construct a counterselectable marker for F. columnare. F. columnare carrying PompA-sacB failed to grow on media containing 10% sucrose. A suicide vector carrying PompA-sacB was constructed, and a gene deletion strategy was developed. Using this approach, the chondroitin lyase-encoding genes, cslA and cslB, were deleted. The ΔcslA and ΔcslB mutants were both partially deficient in digestion of chondroitin sulfate A, whereas a double mutant (ΔcslA ΔcslB) was completely deficient in chondroitin lyase activity. Cells of F. columnare wild-type strain G4 and of the chondroitin lyase-deficient ΔcslA ΔcslB mutant exhibited similar levels of virulence toward grass carp in single-strain infections. Coinfections, however, revealed a competitive advantage for the wild type over the chondroitin lyase mutant. The results indicate that chondroitin lyases are not essential virulence factors of F. columnare but may contribute to the ability of the pathogen to compete and cause disease in natural infections. The gene deletion method developed in this study may be employed to investigate the virulence factors of this bacterium and may have wide application in many other members of the phylum Bacteroidetes.
[Mh] Termos MeSH primário: Condroitina Liases/metabolismo
Infecções por Flavobacteriaceae/veterinária
Flavobacterium/enzimologia
Flavobacterium/fisiologia
Deleção de Genes
Fatores de Virulência/metabolismo
[Mh] Termos MeSH secundário: Animais
Carpas
Condroitina Liases/deficiência
Condroitina Liases/genética
Sulfatos de Condroitina/metabolismo
DNA Bacteriano/química
DNA Bacteriano/genética
Infecções por Flavobacteriaceae/microbiologia
Infecções por Flavobacteriaceae/patologia
Flavobacterium/genética
Dados de Sequência Molecular
Análise de Sequência de DNA
Virulência
Fatores de Virulência/deficiência
Fatores de Virulência/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (DNA, Bacterial); 0 (Virulence Factors); 9007-28-7 (Chondroitin Sulfates); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1607
[Cu] Atualização por classe:160501
[Lr] Data última revisão:
160501
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150809
[St] Status:MEDLINE
[do] DOI:10.1128/AEM.01586-15


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[PMID]:25912370
[Au] Autor:Kale V; Friðjónsson Ó; Jónsson JÓ; Kristinsson HG; Ómarsdóttir S; Hreggviðsson GÓ
[Ad] Endereço:Matís, Vínlandsleið 12, 113, Reykjavík, Iceland.
[Ti] Título:Chondroitin Lyase from a Marine Arthrobacter sp. MAT3885 for the Production of Chondroitin Sulfate Disaccharides.
[So] Source:Mar Biotechnol (NY);17(4):479-92, 2015 Aug.
[Is] ISSN:1436-2236
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Chondroitin sulfate (CS) saccharides from cartilage tissues have potential application in medicine or as dietary supplements due to their therapeutic bioactivities. Studies have shown that depolymerized CS saccharides may display enhanced bioactivity. The objective of this study was to isolate a CS-degrading enzyme for an efficient production of CS oligo- or disaccharides. CS-degrading bacteria from marine environments were enriched using in situ artificial support colonization containing CS from shark cartilage as substrate. Subsequently, an Arthrobacter species (strain MAT3885) efficiently degrading CS was isolated from a CS enrichment culture. The genomic DNA from strain MAT3885 was pyro-sequenced by using the 454 FLX sequencing technology. Following assembly and annotation, an orf, annotated as family 8 polysaccharide lyase genes, was identified, encoding an amino acid sequence with a similarity to CS lyases according to NCBI blastX. The gene, designated choA1, was cloned in Escherichia coli and expressed downstream of and in frame with the E. coli malE gene for obtaining a high yield of soluble recombinant protein. Applying a dual-tag system (MalE-Smt3-ChoA1), the MalE domain was separated from ChoA1 with proteolytic cleavage using Ulp1 protease. ChoA1 was defined as an AC-type enzyme as it degraded chondroitin sulfate A, C, and hyaluronic acid. The optimum activity of the enzyme was at pH 5.5-7.5 and 40 °C, running a 10-min reaction. The native enzyme was estimated to be a monomer. As the recombinant chondroitin sulfate lyase (designated as ChoA1R) degraded chondroitin sulfate efficiently compared to a benchmark enzyme, it may be used for the production of chondroitin sulfate disaccharides for the food industry or health-promoting products.
[Mh] Termos MeSH primário: Arthrobacter/enzimologia
Condroitina Liases/genética
Condroitina Liases/metabolismo
Sulfatos de Condroitina/biossíntese
Dissacarídeos/biossíntese
Microbiologia Industrial/métodos
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Arthrobacter/genética
Sequência de Bases
Cartilagem/metabolismo
Biologia Computacional
Cisteína Endopeptidases
Concentração de Íons de Hidrogênio
Anotação de Sequência Molecular
Dados de Sequência Molecular
Estrutura Terciária de Proteína
Proteólise
Análise de Sequência de DNA
Tubarões
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Disaccharides); 9007-28-7 (Chondroitin Sulfates); EC 3.4.22.- (Cysteine Endopeptidases); EC 3.4.22.- (Ulp1 protease); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1604
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:150428
[St] Status:MEDLINE
[do] DOI:10.1007/s10126-015-9629-9


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[PMID]:25122756
[Au] Autor:Han W; Wang W; Zhao M; Sugahara K; Li F
[Ad] Endereço:From the National Glycoengineering Research Center, and State Key Laboratory of Microbial Technology, Shandong University, Jinan 250100, China and.
[Ti] Título:A novel eliminase from a marine bacterium that degrades hyaluronan and chondroitin sulfate.
[So] Source:J Biol Chem;289(40):27886-98, 2014 Oct 03.
[Is] ISSN:1083-351X
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Lyases cleave glycosaminoglycans (GAGs) in an eliminative mechanism and are important tools for the structural analysis and oligosaccharide preparation of GAGs. Various GAG lyases have been identified from terrestrial but not marine organisms even though marine animals are rich in GAGs with unique structures and functions. Herein we isolated a novel GAG lyase for the first time from the marine bacterium Vibrio sp. FC509 and then recombinantly expressed and characterized it. It showed strong lyase activity toward hyaluronan (HA) and chondroitin sulfate (CS) and was designated as HA and CS lyase (HCLase). It exhibited the highest activities to both substrates at pH 8.0 and 0.5 m NaCl at 30 °C. Its activity toward HA was less sensitive to pH than its CS lyase activity. As with most other marine enzymes, HCLase is a halophilic enzyme and very stable at temperatures from 0 to 40 °C for up to 24 h, but its activity is independent of divalent metal ions. The specific activity of HCLase against HA and CS reached a markedly high level of hundreds of thousands units/mg of protein under optimum conditions. The HCLase-resistant tetrasaccharide Δ(4,5)HexUAα1-3GalNAc(6-O-sulfate)ß1-4GlcUA(2-O-sulfate)ß1-3GalNAc(6-O-sulfate) was isolated from CS-D, the structure of which indicated that HCLase could not cleave the galactosaminidic linkage bound to 2-O-sulfated d-glucuronic acid (GlcUA) in CS chains. Site-directed mutagenesis indicated that HCLase may work via a catalytic mechanism in which Tyr-His acts as the Brønsted base and acid. Thus, the identification of HCLase provides a useful tool for HA- and CS-related research and applications.
[Mh] Termos MeSH primário: Proteínas de Bactérias/metabolismo
Condroitina Liases/metabolismo
Condroitina/metabolismo
Ácido Hialurônico/metabolismo
Água do Mar/microbiologia
Vibrio/enzimologia
Vibrio/isolamento & purificação
[Mh] Termos MeSH secundário: Proteínas de Bactérias/química
Proteínas de Bactérias/genética
Condroitina/química
Condroitina Liases/química
Condroitina Liases/genética
Estabilidade Enzimática
Ácido Hialurônico/química
Dados de Sequência Molecular
Filogenia
Especificidade por Substrato
Vibrio/química
Vibrio/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Bacterial Proteins); 9004-61-9 (Hyaluronic Acid); 9007-27-6 (Chondroitin); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1412
[Cu] Atualização por classe:151003
[Lr] Data última revisão:
151003
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140815
[St] Status:MEDLINE
[do] DOI:10.1074/jbc.M114.590752


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[PMID]:24446551
[Au] Autor:Kawaguchi Y; Sugiura N; Kimata K; Kimura M; Kakuta Y
[Ti] Título:The crystal structure of novel chondroitin lyase ODV-E66, a baculovirus envelope protein.
[So] Source:FEBS Lett;587(24):3943-8, 2013 Dec 11.
[Is] ISSN:1873-3468
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Chondroitin lyases have been known as pathogenic bacterial enzymes that degrade chondroitin. Recently, baculovirus envelope protein ODV-E66 was identified as the first reported viral chondroitin lyase. ODV-E66 has low sequence identity with bacterial lyases at <12%, and unique characteristics reflecting the life cycle of baculovirus. To understand ODV-E66's structural basis, the crystal structure was determined and it was found that the structural fold resembled that of polysaccharide lyase 8 proteins and that the catalytic residues were also conserved. This structure enabled discussion of the unique substrate specificity and the stability of ODV-E66 as well as the host specificity of baculovirus.
[Mh] Termos MeSH primário: Baculoviridae/enzimologia
Condroitina Liases/química
Proteínas do Envelope Viral/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Baculoviridae/genética
Condroitina Liases/genética
Condroitina Liases/metabolismo
Cristalografia por Raios X
Análise Mutacional de DNA
Estabilidade Enzimática
Modelos Moleculares
Dados de Sequência Molecular
Conformação Proteica
Dobramento de Proteína
Homologia de Sequência de Aminoácidos
Proteínas do Envelope Viral/genética
Proteínas do Envelope Viral/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Viral Envelope Proteins); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1402
[Cu] Atualização por classe:140117
[Lr] Data última revisão:
140117
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:140122
[St] Status:MEDLINE


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[PMID]:23270863
[Au] Autor:Lee HY; Han L; Roughley PJ; Grodzinsky AJ; Ortiz C
[Ad] Endereço:Department of Electrical Engineering and Computer Science, Massachusetts Institute of Technology, 77 Massachusetts Avenue, Cambridge, MA 02139, USA.
[Ti] Título:Age-related nanostructural and nanomechanical changes of individual human cartilage aggrecan monomers and their glycosaminoglycan side chains.
[So] Source:J Struct Biol;181(3):264-73, 2013 Mar.
[Is] ISSN:1095-8657
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The nanostructure and nanomechanical properties of aggrecan monomers extracted and purified from human articular cartilage from donors of different ages (newborn, 29 and 38 year old) were directly visualized and quantified via atomic force microscopy (AFM)-based imaging and force spectroscopy. AFM imaging enabled direct comparison of full length monomers at different ages. The higher proportion of aggrecan fragments observed in adult versus newborn populations is consistent with the cumulative proteolysis of aggrecan known to occur in vivo. The decreased dimensions of adult full length aggrecan (including core protein and glycosaminoglycan (GAG) chain trace length, end-to-end distance and extension ratio) reflect altered aggrecan biosynthesis. The demonstrably shorter GAG chains observed in adult full length aggrecan monomers, compared to newborn monomers, also reflects markedly altered biosynthesis with age. Direct visualization of aggrecan subjected to chondroitinase and/or keratanase treatment revealed conformational properties of aggrecan monomers associated with chondroitin sulfate (CS) and keratan sulfate (KS) GAG chains. Furthermore, compressive stiffness of chemically end-attached layers of adult and newborn aggrecan was measured in various ionic strength aqueous solutions. Adult aggrecan was significantly weaker in compression than newborn aggrecan even at the same total GAG density and bath ionic strength, suggesting the importance of both electrostatic and non-electrostatic interactions in nanomechanical stiffness. These results provide molecular-level evidence of the effects of age on the conformational and nanomechanical properties of aggrecan, with direct implications for the effects of aggrecan nanostructure on the age-dependence of cartilage tissue biomechanical and osmotic properties.
[Mh] Termos MeSH primário: Agrecanas/metabolismo
Envelhecimento/fisiologia
Cartilagem/metabolismo
Glicosaminoglicanos/metabolismo
[Mh] Termos MeSH secundário: Adulto
Agrecanas/ultraestrutura
Condroitina Liases/metabolismo
Glicosaminoglicanos/ultraestrutura
Glicosídeo Hidrolases/metabolismo
Seres Humanos
Técnicas In Vitro
Recém-Nascido
Microscopia de Força Atômica
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T; RESEARCH SUPPORT, U.S. GOV'T, NON-P.H.S.
[Nm] Nome de substância:
0 (Aggrecans); 0 (Glycosaminoglycans); EC 3.2.1.- (Glycoside Hydrolases); EC 3.2.1.103 (keratan-sulfate endo-1,4-beta-galactosidase); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1308
[Cu] Atualização por classe:170220
[Lr] Data última revisão:
170220
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:121229
[St] Status:MEDLINE


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[PMID]:22345629
[Au] Autor:Pomin VH; Park Y; Huang R; Heiss C; Sharp JS; Azadi P; Prestegard JH
[Ad] Endereço:Complex Carbohydrate Research Center, University of Georgia, Athens, GA 30602, USA.
[Ti] Título:Exploiting enzyme specificities in digestions of chondroitin sulfates A and C: production of well-defined hexasaccharides.
[So] Source:Glycobiology;22(6):826-38, 2012 Jun.
[Is] ISSN:1460-2423
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:Interactions between proteins and glycosaminoglycans (GAGs) of the extracellular matrix are important to the regulation of cellular processes including growth, differentiation and migration. Understanding these processes can benefit greatly from the study of protein-GAG interactions using GAG oligosaccharides of well-defined structure. Materials for such studies have, however, been difficult to obtain because of challenges in synthetic approaches and the extreme structural heterogeneity in GAG polymers. Here, it is demonstrated that diversity in structures of oligosaccharides derived by limited enzymatic digestion of materials from natural sources can be greatly curtailed by a proper selection of combinations of source materials and digestive enzymes, a process aided by an improved understanding of the specificities of certain commercial preparations of hydrolases and lyases. Separation of well-defined oligosaccharides can then be accomplished by size-exclusion chromatography followed by strong anion-exchange chromatography. We focus here on two types of chondroitin sulfate (CS) as starting material (CS-A, and CS-C) and the use of three digestive enzymes with varying specificities (testicular hyaluronidase and bacterial chondroitinases ABC and C). Analysis using nuclear magnetic resonance and mass spectrometry focuses on isolated CS disaccharides and hexasaccharides. In all, 15 CS hexasaccharides have been isolated and characterized. These serve as useful contributions to growing libraries of well-defined GAG oligosaccharides that can be used in further biophysical assays.
[Mh] Termos MeSH primário: Condroitina Liases/metabolismo
Sulfatos de Condroitina/metabolismo
Hialuronoglucosaminidase/metabolismo
Oligossacarídeos/biossíntese
[Mh] Termos MeSH secundário: Animais
Condroitina Liases/isolamento & purificação
Hialuronoglucosaminidase/isolamento & purificação
Masculino
Oligossacarídeos/metabolismo
Psoríase/enzimologia
Ovinos
Especificidade por Substrato
Testículo/química
[Pt] Tipo de publicação:JOURNAL ARTICLE; RESEARCH SUPPORT, N.I.H., EXTRAMURAL; RESEARCH SUPPORT, NON-U.S. GOV'T
[Nm] Nome de substância:
0 (Oligosaccharides); 9007-28-7 (Chondroitin Sulfates); EC 3.2.1.35 (Hyaluronoglucosaminidase); EC 4.2.2.- (Chondroitin Lyases)
[Em] Mês de entrada:1301
[Cu] Atualização por classe:161019
[Lr] Data última revisão:
161019
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:120221
[St] Status:MEDLINE
[do] DOI:10.1093/glycob/cws055



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