Base de dados : MEDLINE
Pesquisa : D09.408.320 [Categoria DeCS]
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[PMID]:28687490
[Au] Autor:Yoshida H; Nishi N; Wada K; Nakamura T; Hirashima M; Kuwabara N; Kato R; Kamitori S
[Ad] Endereço:Life Science Research Center and Faculty of Medicine, Kagawa University, 1750-1, Ikenobe, Miki-cho, Kita-gun, Kagawa 761-0793, Japan.
[Ti] Título:X-ray structure of a protease-resistant mutant form of human galectin-9 having two carbohydrate recognition domains with a metal-binding site.
[So] Source:Biochem Biophys Res Commun;490(4):1287-1293, 2017 Sep 02.
[Is] ISSN:1090-2104
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:Galectin-9 (G9) is a tandem-repeat type ß-galactoside-specific animal lectin having N-terminal and C-terminal carbohydrate recognition domains (N-CRD and C-CRD, respectively) joined by a linker peptide that is involved in the immune system. G9 is divalent in glycan binding, and structural information about the spatial arrangement of the two CRDs is very important for elucidating its biological functions. As G9 is protease sensitive due to the long linker, the protease-resistant mutant form of G9 (G9Null) was developed by modification of the linker peptide, while retaining its biological functions. The X-ray structure of a mutant form of G9Null with the replacement of Arg221 by Ser (G9Null_R221S) having two CRDs was determined. The structure of G9Null_R221S was compact to associate the two CRDs in the back-to-back orientation with a large interface area, including hydrogen bonds and hydrophobic interactions. A metal ion was newly found in the galectin structure, possibly contributing to the stable structure of protein. The presented X-ray structure was thought to be one of the stable structures of G9, which likely occurs in solution. This was supported by structural comparisons with other tandem-repeated galectins and the analyses of protein thermostability by CD spectra measurements.
[Mh] Termos MeSH primário: Galactosídeos/química
Galectinas/química
Metais/química
Mutação
[Mh] Termos MeSH secundário: Adenoviridae/química
Sequência de Aminoácidos
Animais
Sítios de Ligação
Clonagem Molecular
Cristalografia por Raios X
Escherichia coli/genética
Escherichia coli/metabolismo
Galectinas/genética
Galectinas/metabolismo
Expressão Gênica
Seres Humanos
Ligações de Hidrogênio
Interações Hidrofóbicas e Hidrofílicas
Modelos Moleculares
Ligação Proteica
Conformação Proteica em alfa-Hélice
Conformação Proteica em Folha beta
Domínios e Motivos de Interação entre Proteínas
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Alinhamento de Sequência
Homologia de Sequência de Aminoácidos
Toxascaris/química
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Galactosides); 0 (Galectins); 0 (LGALS9 protein, human); 0 (Metals); 0 (Recombinant Proteins); 0 (beta-galactoside)
[Em] Mês de entrada:1708
[Cu] Atualização por classe:170808
[Lr] Data última revisão:
170808
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170709
[St] Status:MEDLINE


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[PMID]:28359553
[Au] Autor:Schick D; Schwack W
[Ad] Endereço:Institute of Food Chemistry, University of Hohenheim, Garbenstraße 28, D-70599 Stuttgart, Germany.
[Ti] Título:Planar yeast estrogen screen with resorufin-ß-d-galactopyranoside as substrate.
[So] Source:J Chromatogr A;1497:155-163, 2017 May 12.
[Is] ISSN:1873-3778
[Cp] País de publicação:Netherlands
[La] Idioma:eng
[Ab] Resumo:For the planar yeast estrogen screen (pYES), 4-methylumbelliferyl-ß-d-galactopyranoside was generally employed as substrate, delivering blue fluorescing 4-methylumbelliferone after enzymatic cleavage by the YES reporter ß-d-galactosidase as the positive signal for the presence of estrogen active compounds (EAC). As environmental samples like waste water also contain blue fluorescent components, it is difficult to differentiate them from pYES signals. Therefore, resorufin-ß-d-galactopyranoside (RGP), providing the orange fluorescing resorufin after enzymatic cleavage, was introduced as pYES substrate to determine EAC. With 17ß-estradiol (E2) and 17α-ethinylestradiol (EE2), mean limits of detection and quantitation of 3.5 and 6.5pg/zone, respectively, were determined. Obtained recoveries for both E2 and EE2 from spiked water samples in a concentration range of 2-20ng/L were close to 100%. The application of the RGP-pYES on waste water influent and effluent samples showed the clear detection of EAC without interferences. Estrone (E1), Estriol, E2, and an unknown EAC were found in the influent sample (E2 with a mean of 16.9 ng/L and a precision of 11% RSD; n=4), while another unknown EAC was observed in the effluent sample. In addition, the presence of conjugated EAC in the influent was demonstrated by hydrolysis with ß-glucuronidase, when the signals of E1 and the unknown increased by about 25% and 100%, respectively.
[Mh] Termos MeSH primário: Cromatografia em Camada Delgada
Disruptores Endócrinos/análise
Galactosídeos/metabolismo
Oxazinas/metabolismo
Saccharomyces cerevisiae/metabolismo
Poluentes Químicos da Água/análise
[Mh] Termos MeSH secundário: Estradiol/análise
Etinilestradiol/análise
Concentração de Íons de Hidrogênio
Limite de Detecção
Saccharomyces cerevisiae/enzimologia
Especificidade por Substrato
Águas Residuais/análise
beta-Galactosidase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Endocrine Disruptors); 0 (Galactosides); 0 (Oxazines); 0 (Waste Water); 0 (Water Pollutants, Chemical); 423D2T571U (Ethinyl Estradiol); 4TI98Z838E (Estradiol); 95079-19-9 (resorufin galactopyranoside); EC 3.2.1.23 (beta-Galactosidase)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:170516
[Lr] Data última revisão:
170516
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170401
[St] Status:MEDLINE


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[PMID]:28317475
[Au] Autor:Matsunaga E; Higuchi Y; Mori K; Yairo N; Toyota S; Oka T; Tashiro K; Takegawa K
[Ad] Endereço:a Faculty of Agriculture, Department of Bioscience and Biotechnology , Kyushu University , Fukuoka , Japan.
[Ti] Título:Characterization of a PA14 domain-containing galactofuranose-specific ß-d-galactofuranosidase from Streptomyces sp.
[So] Source:Biosci Biotechnol Biochem;81(7):1314-1319, 2017 Jul.
[Is] ISSN:1347-6947
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:As a constituent of polysaccharides and glycoconjugates, ß-d-galactofuranose (Galf) exists in several pathogenic microorganisms. Although we recently identified a ß-d-galactofuranosidase (Galf-ase) gene, ORF1110, in the Streptomyces strain JHA19, very little is known about the Galf-ase gene. Here, we characterized a strain, named JHA26, in the culture supernatant of which exhibited Galf-ase activity for 4-nitrophenyl ß-d-galactofuranoside (pNP-ß-d-Galf) as a substrate. Draft genome sequencing of the JHA26 strain revealed a putative gene, termed ORF0643, that encodes Galf-ase containing a PA14 domain, which is thought to function in substrate recognition. The recombinant protein expressed in Escherichia coli showed the Galf-specific Galf-ase activity and also released galactose residue of the polysaccharide galactomannan prepared from Aspergillus fumigatus, suggesting that this enzyme is an exo-type Galf-ase. BLAST searches using the amino acid sequences of ORF0643 and ORF1110 Galf-ases revealed two types of Galf-ases in Actinobacteria, suggesting that Galf-specific Galf-ases may exhibit discrete substrate specificities.
[Mh] Termos MeSH primário: Proteínas de Bactérias/química
Galactose/análogos & derivados
Galactosídeos/química
Glicosídeo Hidrolases/química
Mananas/química
Streptomyces/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Clonagem Molecular
Escherichia coli/genética
Escherichia coli/metabolismo
Galactose/metabolismo
Galactosídeos/metabolismo
Expressão Gênica
Glicosídeo Hidrolases/genética
Glicosídeo Hidrolases/metabolismo
Cinética
Mananas/metabolismo
Filogenia
Domínios Proteicos
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/metabolismo
Alinhamento de Sequência
Homologia de Sequência de Aminoácidos
Streptomyces/classificação
Streptomyces/enzimologia
Especificidade por Substrato
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Galactosides); 0 (Mannans); 0 (Recombinant Proteins); 100645-45-2 (4-nitrophenylgalactofuranoside); 11078-30-1 (galactomannan); EC 3.2.1.- (Glycoside Hydrolases); EC 3.2.1.146 (exo-beta-D-galactofuranosidase); X2RN3Q8DNE (Galactose)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170707
[Lr] Data última revisão:
170707
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170321
[St] Status:MEDLINE
[do] DOI:10.1080/09168451.2017.1300518


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[PMID]:28259967
[Au] Autor:Shen L; Luo Z; Wu J; Qiu L; Luo M; Ke Q; Dong X
[Ad] Endereço:Department of Clinical Oncology, Taihe Hospital, Hubei University of Medicine, Shiyan, Hubei 442000, P.R. China.
[Ti] Título:Enhanced expression of α2,3-linked sialic acids promotes gastric cancer cell metastasis and correlates with poor prognosis.
[So] Source:Int J Oncol;50(4):1201-1210, 2017 Apr.
[Is] ISSN:1791-2423
[Cp] País de publicação:Greece
[La] Idioma:eng
[Ab] Resumo:Gastric cancer (GC) is a highly metastatic disease and one of the leading causes of cancer death in the world. Aberrant glycosylation is one of many molecular changes that accompany malignant transformation. This study was aimed at identification of glycan profiling changes in GC progression and its potential mechanisms. We employed a microarray with 91 lectins to compare the differential glycans in the three human GC cell lines, SGC-7901, BGC-823 and MGC-803. According to glycan-binding specificities of lectins, all GC cell lines expressed common sugar structures, such as mannose, galactose and fucose. Importantly, we found that the binding of Maackia amurensis lectin-I (MAL-I) to GC cells was proportional to their metastatic capacity. Further analysis revealed that the level of α2,3-linked sialic acids (α2-3Sia), which can be recognized by MAL-I, was significantly overexpressed in MGC-803 cells, while low expression was detected in SGC-7901 cells. In addition, the mRNA and protein expression levels of ß-galactoside α2,3-sialyltransferase IV (ST3Gal-IV), which was related to the synthesis of α2-3Sia, were substantially increased in MGC-803 cells. Knockdown of ST3Gal-IV in MGC-803 cells led to a decreased level of α2-3Sia and decreased ability of invasion and migration. Exogenous expression of ST3Gal-IV in SGC-7901 cells enhanced cell migration, invasion and the content of α2-3Sia. Furthermore, the staining of MAL-I in GC tissues showed that high expression of α2-3Sia was closely correlated with lymph node metastasis, TNM stage and poor overall survival. These findings lead to better understanding of the function of α2-3Sia in the progression and metastasis of GC. This property may be important for developing new therapeutic approaches for GC.
[Mh] Termos MeSH primário: Hexoses/metabolismo
Lectinas/metabolismo
Ácidos Siálicos/biossíntese
Sialiltransferases/metabolismo
Neoplasias Gástricas/metabolismo
Neoplasias Gástricas/patologia
[Mh] Termos MeSH secundário: Biomarcadores Tumorais/biossíntese
Linhagem Celular Tumoral
Membrana Celular/metabolismo
Movimento Celular
Feminino
Galactosídeos/metabolismo
Glicosilação
Seres Humanos
Metástase Linfática
Maackia/química
Masculino
Análise em Microsséries
Meia-Idade
Terapia de Alvo Molecular
Estadiamento de Neoplasias
Polissacarídeos/metabolismo
Prognóstico
RNA Mensageiro/metabolismo
Neoplasias Gástricas/tratamento farmacológico
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Biomarkers, Tumor); 0 (Galactosides); 0 (Hexoses); 0 (Lectins); 0 (Polysaccharides); 0 (RNA, Messenger); 0 (Sialic Acids); 0 (beta-galactoside); EC 2.4.99.- (Sialyltransferases); EC 2.4.99.4 (beta-galactoside alpha-2,3-sialyltransferase)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:170717
[Lr] Data última revisão:
170717
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170306
[St] Status:MEDLINE
[do] DOI:10.3892/ijo.2017.3882


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[PMID]:28193904
[Au] Autor:Narang A; Oehler S
[Ad] Endereço:Department of Biochemical Engineering and Biotechnology, Indian Institute of Technology Delhi, Hauz Khas, New Delhi, India.
[Ti] Título:Effector Overlap between the and Operons of Escherichia coli: Induction of the Operon with ß-Galactosides.
[So] Source:J Bacteriol;199(9), 2017 May 01.
[Is] ISSN:1098-5530
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The (lactose) operon (which processes ß-galactosides) and the (melibiose) operon (which processes α-galactosides) of have a close historical connection. A number of shared substrates and effectors of the permeases and regulatory proteins have been reported over the years. Until now, ß-thiogalactosides like TMG (methyl-ß-d-thiogalactopyranoside) and IPTG (isopropyl-ß-d-thiogalactopyranoside) have not generally been considered to be inducers of the operon. The same is true for ß-galactosides such as lactose [ß-d-galactopyranosyl-(1→4)-d-glucose], which is a substrate but is not itself an inducer of the operon. This report shows that all three sugars can induce the operon significantly when they are accumulated in the cell by Lac permease. Strong induction by ß-thiogalactosides is observed in the presence of Lac permease, and strong induction by lactose (more than 200-fold) is observed in the absence of ß-galactosidase. This finding calls for reevaluation of TMG uptake experiments as assays for Lac permease that were performed with strains. The typical textbook picture of bacterial operons is that of stand-alone units of genetic information that perform, in a regulated manner, well-defined cellular functions. Less attention is given to the extensive interactions that can be found between operons. Well-described examples of such interactions are the effector molecules shared by the and operons. Here, we show that this set has to be extended to include ß-galactosides, which have been, until now, considered not to effect the expression of the operon. That they can be inducers of the operon as well as the operon has not been noted in decades of research because of the genetic background used in previous studies.
[Mh] Termos MeSH primário: Escherichia coli/genética
Óperon Lac
Melibiose/genética
Óperon
[Mh] Termos MeSH secundário: Galactosídeos/genética
Galactosídeos/farmacologia
Glucose/farmacologia
Lactose/farmacologia
Melibiose/metabolismo
Proteínas de Membrana Transportadoras
beta-Galactosidase/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Galactosides); 0 (Membrane Transport Proteins); 0 (beta-galactoside); 9068-45-5 (lactose permease); 9B1VBE526I (Melibiose); EC 3.2.1.23 (beta-Galactosidase); IY9XDZ35W2 (Glucose); J2B2A4N98G (Lactose)
[Em] Mês de entrada:1707
[Cu] Atualização por classe:171011
[Lr] Data última revisão:
171011
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170215
[St] Status:MEDLINE


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[PMID]:28191939
[Au] Autor:Bars-Cortina D; Macià A; Iglesias I; Romero MP; Motilva MJ
[Ad] Endereço:Food Technology Department, XaRTA-TPV, Agrotecnio Center, Escola Tècnica Superior d'Enginyeria Agrària, University of Lleida , Avinguda Alcalde Rovira Roure 191, 25198 Lleida, Catalonia, Spain.
[Ti] Título:Phytochemical Profiles of New Red-Fleshed Apple Varieties Compared with Traditional and New White-Fleshed Varieties.
[So] Source:J Agric Food Chem;65(8):1684-1696, 2017 Mar 01.
[Is] ISSN:1520-5118
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:This study is an exhaustive chemical characterization of the phenolic compounds, triterpenes, and organic and ascorbic acids in red-fleshed apple varieties obtained by different breeding programs and using five traditional and new white-fleshed apple cultivars as reference. To carry out these analyses, solid-liquid extraction (SLE) and ultraperformance liquid chromatography coupled to tandem mass spectrometry (UPLC-MS/MS) were used. The results showed that the red-fleshed apples contained, in either the flesh or peel, higher amounts of phenolic acids (chlorogenic acid), anthocyanins (cyanidin-3-O-galactoside), dihydrochalcones (phloretin xylosyl glucoside), and organic acids (malic acid) but a lower amount of flavan-3-ols than the white-fleshed apples. These quantitative differences could be related to an up-regulation of anthocyanins, dihydrochalcones, and malic acid and a down-regulation of flavan-3-ols (anthocyanin precursors) in both the flesh and peel of the red-fleshed apple varieties. The reported results should be considered preliminary because the complete phytochemical characterization of the red-fleshed apple cultivars will be extended to consecutive harvest seasons.
[Mh] Termos MeSH primário: Malus/química
Compostos Fitoquímicos/análise
Extratos Vegetais/análise
[Mh] Termos MeSH secundário: Antocianinas/análise
Frutas/química
Frutas/classificação
Galactosídeos/análise
Malus/classificação
Polifenóis/análise
Espectrometria de Massas em Tandem
[Pt] Tipo de publicação:COMPARATIVE STUDY; JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anthocyanins); 0 (Galactosides); 0 (Phytochemicals); 0 (Plant Extracts); 0 (Polyphenols); FC7L938Y12 (cyanidin 3-galactoside)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171116
[Lr] Data última revisão:
171116
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170214
[St] Status:MEDLINE
[do] DOI:10.1021/acs.jafc.6b02931


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[PMID]:28150103
[Au] Autor:Carneiro RF; Torres RC; Chaves RP; de Vasconcelos MA; de Sousa BL; Goveia AC; Arruda FV; Matos MN; Matthews-Cascon H; Freire VN; Teixeira EH; Nagano CS; Sampaio AH
[Ad] Endereço:Laboratório de Biotecnologia Marinha - BioMar-Lab, Departamento de Engenharia de Pesca, Universidade Federal do Ceará, Campus do Pici s/n, bloco 871, Av. Mister Hull, Box 6043, Fortaleza, Ceará, 60440-970, Brazil.
[Ti] Título:Purification, Biochemical Characterization, and Amino Acid Sequence of a Novel Type of Lectin from Aplysia dactylomela Eggs with Antibacterial/Antibiofilm Potential.
[So] Source:Mar Biotechnol (NY);19(1):49-64, 2017 Feb.
[Is] ISSN:1436-2236
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:A new lectin from Aplysia dactylomela eggs (ADEL) was isolated by affinity chromatography on HCl-activated Sepharose™ media. Hemagglutination caused by ADEL was inhibited by several galactosides, mainly galacturonic acid (Ka = 6.05 × 10 M ). The primary structure of ADEL consists of 217 residues, including 11 half-cystines involved in five intrachain and one interchain disulfide bond, resulting in a molecular mass of 57,228 ± 2 Da, as determined by matrix-assisted laser desorption/ionization time of flight mass spectrometry. ADEL showed high similarity with lectins isolated from Aplysia eggs, but not with other known lectins, indicating that these lectins could be grouped into a new family of animal lectins. Three glycosylation sites were found in its polypeptide backbone. Data from peptide-N-glycosidase F digestion and MS suggest that all oligosaccharides attached to ADEL are high in mannose. The secondary structure of ADEL is predominantly ß-sheet, and its tertiary structure is sensitive to the presence of ligands, as observed by CD. A 3D structure model of ADEL was created and shows two domains connected by a short loop. Domain A is composed of a flat three-stranded and a curved five-stranded ß-sheet, while domain B presents a flat three-stranded and a curved four-stranded ß-sheet. Molecular docking revealed favorable binding energies for interactions between lectin and galacturonic acid, lactose, galactosamine, and galactose. Moreover, ADEL was able to agglutinate and inhibit biofilm formation of Staphylococcus aureus, suggesting that this lectin may be a potential alternative to conventional use of antimicrobial agents in the treatment of infections caused by Staphylococcal biofilms.
[Mh] Termos MeSH primário: Antibacterianos/química
Aplysia/química
Biofilmes/efeitos dos fármacos
Lectinas/química
Staphylococcus aureus/efeitos dos fármacos
Zigoto/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos
Animais
Antibacterianos/isolamento & purificação
Antibacterianos/metabolismo
Antibacterianos/farmacologia
Aplysia/genética
Aplysia/metabolismo
Biofilmes/crescimento & desenvolvimento
Escherichia coli/genética
Escherichia coli/metabolismo
Galactosídeos/farmacologia
Expressão Gênica
Testes de Inibição da Hemaglutinação
Ácidos Hexurônicos/farmacologia
Lectinas/genética
Lectinas/isolamento & purificação
Lectinas/farmacologia
Simulação de Acoplamento Molecular
Domínios Proteicos
Estrutura Secundária de Proteína
Proteínas Recombinantes/química
Proteínas Recombinantes/genética
Proteínas Recombinantes/isolamento & purificação
Proteínas Recombinantes/farmacologia
Alinhamento de Sequência
Staphylococcus aureus/crescimento & desenvolvimento
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Anti-Bacterial Agents); 0 (Galactosides); 0 (Hexuronic Acids); 0 (Lectins); 0 (Recombinant Proteins); 4JK6RN80GF (galacturonic acid)
[Em] Mês de entrada:1705
[Cu] Atualização por classe:171013
[Lr] Data última revisão:
171013
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170203
[St] Status:MEDLINE
[do] DOI:10.1007/s10126-017-9728-x


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[PMID]:28146365
[Au] Autor:Merkwitz C; Blaschuk O; Winkler J; Schulz A; Prömel S; Ricken AM
[Ad] Endereço:Institute of Anatomy (CM, AMR), University of Leipzig, Leipzig, Germany.
[Ti] Título:Advantages and Limitations of Salmon-Gal/Tetrazolium Salt Histochemistry for the Detection of LacZ Reporter Gene Activity in Murine Epithelial Tissue.
[So] Source:J Histochem Cytochem;65(4):197-206, 2017 04.
[Is] ISSN:1551-5044
[Cp] País de publicação:United States
[La] Idioma:eng
[Ab] Resumo:The Escherichia coli LacZ gene is a widely used reporter for gene regulation studies in transgenic mice. It encodes bacterial ß-galactosidase (Bact ß-Gal), which causes insoluble precipitates when exposed to chromogenic homologues of galactose. We and others have recently reported that Bact ß-Gal detection with Salmon-Gal (S-Gal) in combination with nitro blue tetrazolium chloride (NBT) is very sensitive and not prone to interference by acidic endogenous ß-galactosidases. Unfortunately, as we show here, the method appears to be inadequate for evaluation of Bact ß-Gal expression in keratinized epithelial appendages but not in other keratinized epithelia. NBT in the reaction mixture, just as other tetrazolium salts, inevitably causes unwanted staining artifacts in lingual filiform papillae, penile spines, and hair fibers by interacting with keratin sulfhydryl-rich regions. The methodological limitation can be overcome in part by pretreating the tissues before the S-Gal/NBT staining with an iodine-potassium iodide solution. Alternatively, the use of iodonitrotetrazolium chloride instead of NBT in the S-Gal reaction mixture provides enough color resolution to distinguish the specific Bact ß-Gal staining in orange from the artifact staining in dark red. In summary, we provide evidence that S-Gal/NBT histochemistry has limitations, when staining keratinized epithelial appendages.
[Mh] Termos MeSH primário: Corantes/química
Células Epiteliais/metabolismo
Proteínas de Escherichia coli/metabolismo
Galactosídeos/química
Genes Reporter
Óperon Lac
Sais de Tetrazólio/química
Umbeliferonas/química
beta-Galactosidase/metabolismo
[Mh] Termos MeSH secundário: Animais
Proteínas de Escherichia coli/genética
Histocitoquímica/métodos
Camundongos
Camundongos Transgênicos
Especificidade de Órgãos
Coloração e Rotulagem
beta-Galactosidase/genética
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Coloring Agents); 0 (Escherichia coli Proteins); 0 (Galactosides); 0 (Tetrazolium Salts); 0 (Umbelliferones); 0 (cyclohexenoesculetin-beta-galactoside); EC 3.2.1.23 (beta-Galactosidase)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170824
[Lr] Data última revisão:
170824
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170202
[St] Status:MEDLINE
[do] DOI:10.1369/0022155417690336


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[PMID]:28103425
[Au] Autor:Okuyama M; Matsunaga K; Watanabe KI; Yamashita K; Tagami T; Kikuchi A; Ma M; Klahan P; Mori H; Yao M; Kimura A
[Ad] Endereço:Laboratory of Molecular Enzymology, Research Faculty of Agriculture, Hokkaido University, Sapporo, Japan.
[Ti] Título:Efficient synthesis of α-galactosyl oligosaccharides using a mutant Bacteroides thetaiotaomicron retaining α-galactosidase (BtGH97b).
[So] Source:FEBS J;284(5):766-783, 2017 Mar.
[Is] ISSN:1742-4658
[Cp] País de publicação:England
[La] Idioma:eng
[Ab] Resumo:The preparation of a glycosynthase, a catalytic nucleophile mutant of a glycosidase, is a well-established strategy for the effective synthesis of glycosidic linkages. However, glycosynthases derived from α-glycosidases can give poor yields of desired products because they require generally unstable ß-glycosyl fluoride donors. Here, we investigate a transglycosylation catalyzed by a catalytic nucleophile mutant derived from a glycoside hydrolase family (GH) 97 α-galactosidase, using more stable ß-galactosyl azide and α-galactosyl fluoride donors. The mutant enzyme catalyzes the glycosynthase reaction using ß-galactosyl azide and α-galactosyl transfer from α-galactosyl fluoride with assistance of external anions. Formate was more effective at restoring transfer activity than azide. Kinetic analysis suggests that poor transglycosylation in the presence of the azide is because of low activity of the ternary complex between enzyme, ß-galactosyl azide and acceptor. A three-dimensional structure of the mutant enzyme in complex with the transglycosylation product, ß-lactosyl α-d-galactoside, was solved to elucidate the ligand-binding aspects of the α-galactosidase. Subtle differences at the ß→α loops 1, 2 and 3 of the catalytic TIM barrel of the α-galactosidase from those of a homologous GH97 α-glucoside hydrolase seem to be involved in substrate recognitions. In particular, the Trp residues in ß→α loop 1 have separate roles. Trp312 of the α-galactosidase appears to exclude the equatorial hydroxy group at C4 of glucosides, whereas the corresponding Trp residue in the α-glucoside hydrolase makes a hydrogen bond with this hydroxy group. The mechanism of α-galactoside recognition is conserved among GH27, 31, 36 and 97 α-galactosidases. DATABASE: The atomic coordinates (code: 5E1Q) have been deposited in the Protein Data Bank.
[Mh] Termos MeSH primário: Galactosídeos/química
Proteínas Mutantes/química
Oligossacarídeos/biossíntese
alfa-Galactosidase/química
[Mh] Termos MeSH secundário: Sequência de Aminoácidos/genética
Bacteroides thetaiotaomicron/enzimologia
Biocatálise
Catálise
Galactosídeos/metabolismo
Cinética
Conformação Molecular
Proteínas Mutantes/genética
Proteínas Mutantes/metabolismo
Oligossacarídeos/química
Conformação Proteica
Especificidade por Substrato
alfa-Galactosidase/genética
alfa-Galactosidase/metabolismo
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Galactosides); 0 (Mutant Proteins); 0 (Oligosaccharides); EC 3.2.1.22 (alpha-Galactosidase)
[Em] Mês de entrada:1706
[Cu] Atualização por classe:170623
[Lr] Data última revisão:
170623
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170120
[St] Status:MEDLINE
[do] DOI:10.1111/febs.14018


  10 / 1788 MEDLINE  
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[PMID]:28044272
[Au] Autor:Zhang JF; Chen WQ; Chen H
[Ad] Endereço:College of Biology and Environmental Engineering, Zhejiang Shuren University, Hangzhou, 310015, China. grace_zjf@126.com.
[Ti] Título:Gene cloning and expression of a glucoside 3-dehydrogenase from Sphingobacterium faecium ZJF-D6, and used it to produce N-p-nitrophenyl-3-ketovalidamine.
[So] Source:World J Microbiol Biotechnol;33(2):21, 2017 Feb.
[Is] ISSN:1573-0972
[Cp] País de publicação:Germany
[La] Idioma:eng
[Ab] Resumo:In this study, we report the cloning and expression of a functional glucoside 3-dehydrogenase (G3DH) gene from Sphingobacterium faecium ZJF-D6. This gene is 1686 bp in length and encodes a peptide of 562 amino acids. The G3DH gene was successfully expressed in E. coli, and the recombinant enzyme could oxidize glucosides, galactosides and analogues at C-3 position. The sequence and multiple alignment analysis showed that the enzyme has highest identity with G3DHs from Paraglaciecola polaris LMG 21857, Aliiglaciecola lipolytica E3 and Halomonas sp. alpha-15. The recombinant G3DH was purified on Ni-NTA column and exhibited the highest activity at pH 7.6 and 30 °C. It was sensitive to acid and alkali, and showed well thermostability. The SfG3DH could oxidize a wild range of sugars. When recombinant E. coli BL21 cells were used as catalyst, a high rate of conversion to N-p-nitrophenyl-3-ketovalidamine was achieved, and no p-nitroaniline was detected. This process offers a promising approach to fulfill substrate of 3-ketovalidoxylamine A C-N lyase production.
[Mh] Termos MeSH primário: Clonagem Molecular/métodos
Glucose Desidrogenase/genética
Glucose Desidrogenase/metabolismo
Nitrofenóis/metabolismo
Sphingobacterium/enzimologia
[Mh] Termos MeSH secundário: Proteínas de Bactérias/genética
Proteínas de Bactérias/metabolismo
Escherichia coli/genética
Escherichia coli/metabolismo
Galactosídeos/metabolismo
Glucosídeos/metabolismo
Concentração de Íons de Hidrogênio
Proteínas Recombinantes/metabolismo
Homologia de Sequência de Aminoácidos
Sphingobacterium/genética
Especificidade por Substrato
Temperatura Ambiente
[Pt] Tipo de publicação:JOURNAL ARTICLE
[Nm] Nome de substância:
0 (Bacterial Proteins); 0 (Galactosides); 0 (Glucosides); 0 (N-p-nitrophenyl-3-ketovalidamine); 0 (Nitrophenols); 0 (Recombinant Proteins); EC 1.1.1.- (Glucose Dehydrogenases); EC 1.1.99.13 (glucoside 3-dehydrogenase)
[Em] Mês de entrada:1703
[Cu] Atualização por classe:171102
[Lr] Data última revisão:
171102
[Sb] Subgrupo de revista:IM
[Da] Data de entrada para processamento:170104
[St] Status:MEDLINE
[do] DOI:10.1007/s11274-016-2187-0



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