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Shouyi Chen - One of the best experts on this subject based on the ideXlab platform.
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osglu1 a putative membrane bound Endo 1 4 s d glucanase from rice affects plant internode elongation
Plant Molecular Biology, 2006Co-Authors: Hualin Zhou, Yangrong Cao, Tao Chen, Chengcai Chu, Jinsong Zhang, Shouyi ChenAbstract:A dwarf mutant glu was identified from screening of T-DNA tagged rice population. Genetic analysis of the T1 generation of glu revealed that a segregation ratio of wild-type:dwarf phenotype was 3:1, suggesting that the mutated phenotype was controlled by a single recessive nuclear locus. The mutated gene OsGLU1, identified by Tail-PCR, encodes a putative membrane-bound Endo-1,4-β-D-glucanase, which is highly conserved between mono- and dicotyledonous plants. Mutation of OsGLU1 resulted in a reduction in cell elongation, and a decrease in cellulose content but an increase in pectin content, suggesting that OsGLU1 affects the internode elongation and cell wall components of rice plants. Transgenic glu mutants harboring the OsGLU1 gene complemented the mutation and displayed the wild-type phenotype. In addition, OsGLU1 RNAi plants showed similar phenotype as the glu mutant has. These results indicate that OsGLU1 plays important roles in plant cell growth. Gibberellins and brassinosteroids induced OsGLU1 expression. In rice genome, Endo-1,4-β-D-glucanases form a multiple gene family with 15 members, and each may have a distinct expression pattern in different organs. These results indicate that Endo-1, 4-β-D-glucanases may play diverse roles in growth and developmental process of rice plants.
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osglu1 a putative membrane bound Endo 1 4 beta d glucanase from rice affects plant internode elongation
Plant Molecular Biology, 2006Co-Authors: Hualin Zhou, Yangrong Cao, Tao Chen, Chengcai Chu, Jinsong Zhang, Shouyi ChenAbstract:A dwarf mutant glu was identified from screening of T-DNA tagged rice population. Genetic analysis of the T1 generation of glu revealed that a segregation ratio of wild-type:dwarf phenotype was 3:1, suggesting that the mutated phenotype was controlled by a single recessive nuclear locus. The mutated gene OsGLU1, identified by Tail-PCR, encodes a putative membrane-bound Endo-1,4-β-D-glucanase, which is highly conserved between mono- and dicotyledonous plants. Mutation of OsGLU1 resulted in a reduction in cell elongation, and a decrease in cellulose content but an increase in pectin content, suggesting that OsGLU1 affects the internode elongation and cell wall components of rice plants. Transgenic glu mutants harboring the OsGLU1 gene complemented the mutation and displayed the wild-type phenotype. In addition, OsGLU1 RNAi plants showed similar phenotype as the glu mutant has. These results indicate that OsGLU1 plays important roles in plant cell growth. Gibberellins and brassinosteroids induced OsGLU1 expression. In rice genome, Endo-1,4-β-D-glucanases form a multiple gene family with 15 members, and each may have a distinct expression pattern in different organs. These results indicate that Endo-1, 4-β-D-glucanases may play diverse roles in growth and developmental process of rice plants.
Juha Rouvinen - One of the best experts on this subject based on the ideXlab platform.
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structural and functional properties of low molecular weight Endo 1 4 β xylanases
Journal of Biotechnology, 1997Co-Authors: Anneli Torronen, Juha RouvinenAbstract:Abstract There are currently four crystal structures of low molecular weight Endo-1,4-β-xylanases (E.C.3.2.1.8), i.e. family G/11 xylanases, available at the Brookhaven Data Bank: 2 xylanases from Trichoderma reesei (Torronen et al., (1994); Torronen and Rouvinen, (1995)) and one from Bacillus circulans and another from Trichoderma harzianum (Campbell et al., (1993)). They consist of two β-sheets and one α-helix and have been described to resemble a partly-closed right hand. The catalytic residues are two conserved glutamate residues, which are located opposite to each other in an open active site cleft. The catalytic mechanism is thought to resemble that of the widely-studied enzyme lysozyme. The role of one glutamate is to act as an acid/base catalyst whereas the other is a nucleophile and stabilizes the reaction intermediate. Complex structures of partly-bound xylotetraose in mutated XYN from Bacillus circulans (Wakarchuck et al., (1994)a) and three recently-obtained structures of XYNII from Trichoderma reesei with epoxyalkyl-xylose derivatives (Havukainen et al., 1996) have provided important information on substrate binding. Family G/11 xylanases show clear amino acid homology and thus have a common fold. However, variations in their functional properties, such as catalytic activity, substrate cleaving patterns, pH optima and thermostabilities, exist.
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structural and functional properties of low molecular weight Endo 1 4 β xylanases
Journal of Biotechnology, 1997Co-Authors: Anneli Torronen, Juha RouvinenAbstract:There are currently four crystal structures of low molecular weight Endo-1,4-beta-xylanases (E.C.3.2.1.8), i.e. family G/11 xylanases, available at the Brookhaven Data Bank: 2 xylanases from Trichoderma reesei (Torronen et al., 1994; Torronen and Rouvinen, 1995) and one from Bacillus circulans and another from Trichoderma harzianum (Campbell et al., 1993). They consist of two beta-sheets and one alpha-helix and have been described to resemble a partly-closed right hand. The catalytic residues are two conserved glutamate residues, which are located opposite to each other in an open active site cleft. The catalytic mechanism is thought to resemble that of the widely-studied enzyme lysozyme. The role of one glutamate is to act as an acid/base catalyst whereas the other is a nucleophile and stabilizes the reaction intermediate. Complex structures of partly-bound xylotetraose in mutated XYN from Bacillus circulans (Wakarchuck et al., 1994a) and three recently-obtained structures of XYNII from Trichoderma reesei with epoxyalkyl-xylose derivatives (Havukainen et al., 1996) have provided important information on substrate binding. Family G/11 xylanases show clear amino acid homology and thus have a common fold. However, variations in their functional properties, such as catalytic activity, substrate cleaving patterns, pH optima and thermostabilities, exist.
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structural comparison of two major Endo 1 4 xylanases from trichoderma reesei
Biochemistry, 1995Co-Authors: Anneli Torronen, Juha RouvinenAbstract:Three-dimensional structures of two major Endo-1,4-xylanases, XYNI and XYNII from Trichoderma reesei, have been determined by X-ray crystallography. The amino acid sequences of both enzymes are highly homologous (identity approximately 50%), and both XYNI and XYNII exist as a single domain that contains two mostly antiparallel beta-sheets which are packed against each other. The beta-sheet structure is twisted, forming a cleft where the active site is situated. Two glutamic acids in the cleft, Glu75 and Glu164 in XYNI as well as Glu86 and Glu177 in XYNII, are most likely involved in catalysis. Inspection of the structures reveals that the width of the active site cleft and the number of subsites are different in XYNI and XYNII. The active site is narrower in XYNI and probably contains only three subsites, whereas the number of subsites in XYNII is most likely five. Variations in the surroundings of catalytic residue Glu164XYNI/Glu177XYNII are thought to explain the pH optimum differences observed in XYNI and XYNII.
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three dimensional structure of Endo 1 4 beta xylanase ii from trichoderma reesei two conformational states in the active site
The EMBO Journal, 1994Co-Authors: Anneli Torronen, Anu Marjukka Harkki, Juha RouvinenAbstract:Abstract The three-dimensional structure of Endo-1,4-beta-xylanase II (XYNII) from Trichoderma reesei has been determined by X-ray diffraction techniques and refined to a conventional R-factor of 18.3% at 1.8 A resolution. The 190 amino acid length protein was found to exist as a single domain where the main chain folds to form two mostly antiparallel beta-sheets, which are packed against each other in parallel. The beta-sheet structure is twisted, forming a large cleft on one side of the molecule. The structure of XYNII resembles that of Bacillus 1,3-1,4-beta-glucanase. The cleft is an obvious suggestion for an active site, which has putative binding sites for at least four xylose residues. The catalytic residues are apparently the two glutamic acid residues (Glu86 and Glu177) in the middle of the cleft. One structure was determined at pH 5.0, corresponding to the pH optimum of XYNII. The second structure was determined at pH 6.5, where enzyme activity is reduced considerably. A clear structural change was observed, especially in the position of the side chain of Glu177. The observed conformational change is probably important for the mechanism of catalysis in XYNII.
Hualin Zhou - One of the best experts on this subject based on the ideXlab platform.
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osglu1 a putative membrane bound Endo 1 4 s d glucanase from rice affects plant internode elongation
Plant Molecular Biology, 2006Co-Authors: Hualin Zhou, Yangrong Cao, Tao Chen, Chengcai Chu, Jinsong Zhang, Shouyi ChenAbstract:A dwarf mutant glu was identified from screening of T-DNA tagged rice population. Genetic analysis of the T1 generation of glu revealed that a segregation ratio of wild-type:dwarf phenotype was 3:1, suggesting that the mutated phenotype was controlled by a single recessive nuclear locus. The mutated gene OsGLU1, identified by Tail-PCR, encodes a putative membrane-bound Endo-1,4-β-D-glucanase, which is highly conserved between mono- and dicotyledonous plants. Mutation of OsGLU1 resulted in a reduction in cell elongation, and a decrease in cellulose content but an increase in pectin content, suggesting that OsGLU1 affects the internode elongation and cell wall components of rice plants. Transgenic glu mutants harboring the OsGLU1 gene complemented the mutation and displayed the wild-type phenotype. In addition, OsGLU1 RNAi plants showed similar phenotype as the glu mutant has. These results indicate that OsGLU1 plays important roles in plant cell growth. Gibberellins and brassinosteroids induced OsGLU1 expression. In rice genome, Endo-1,4-β-D-glucanases form a multiple gene family with 15 members, and each may have a distinct expression pattern in different organs. These results indicate that Endo-1, 4-β-D-glucanases may play diverse roles in growth and developmental process of rice plants.
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osglu1 a putative membrane bound Endo 1 4 beta d glucanase from rice affects plant internode elongation
Plant Molecular Biology, 2006Co-Authors: Hualin Zhou, Yangrong Cao, Tao Chen, Chengcai Chu, Jinsong Zhang, Shouyi ChenAbstract:A dwarf mutant glu was identified from screening of T-DNA tagged rice population. Genetic analysis of the T1 generation of glu revealed that a segregation ratio of wild-type:dwarf phenotype was 3:1, suggesting that the mutated phenotype was controlled by a single recessive nuclear locus. The mutated gene OsGLU1, identified by Tail-PCR, encodes a putative membrane-bound Endo-1,4-β-D-glucanase, which is highly conserved between mono- and dicotyledonous plants. Mutation of OsGLU1 resulted in a reduction in cell elongation, and a decrease in cellulose content but an increase in pectin content, suggesting that OsGLU1 affects the internode elongation and cell wall components of rice plants. Transgenic glu mutants harboring the OsGLU1 gene complemented the mutation and displayed the wild-type phenotype. In addition, OsGLU1 RNAi plants showed similar phenotype as the glu mutant has. These results indicate that OsGLU1 plays important roles in plant cell growth. Gibberellins and brassinosteroids induced OsGLU1 expression. In rice genome, Endo-1,4-β-D-glucanases form a multiple gene family with 15 members, and each may have a distinct expression pattern in different organs. These results indicate that Endo-1, 4-β-D-glucanases may play diverse roles in growth and developmental process of rice plants.
Anneli Torronen - One of the best experts on this subject based on the ideXlab platform.
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structural and functional properties of low molecular weight Endo 1 4 β xylanases
Journal of Biotechnology, 1997Co-Authors: Anneli Torronen, Juha RouvinenAbstract:Abstract There are currently four crystal structures of low molecular weight Endo-1,4-β-xylanases (E.C.3.2.1.8), i.e. family G/11 xylanases, available at the Brookhaven Data Bank: 2 xylanases from Trichoderma reesei (Torronen et al., (1994); Torronen and Rouvinen, (1995)) and one from Bacillus circulans and another from Trichoderma harzianum (Campbell et al., (1993)). They consist of two β-sheets and one α-helix and have been described to resemble a partly-closed right hand. The catalytic residues are two conserved glutamate residues, which are located opposite to each other in an open active site cleft. The catalytic mechanism is thought to resemble that of the widely-studied enzyme lysozyme. The role of one glutamate is to act as an acid/base catalyst whereas the other is a nucleophile and stabilizes the reaction intermediate. Complex structures of partly-bound xylotetraose in mutated XYN from Bacillus circulans (Wakarchuck et al., (1994)a) and three recently-obtained structures of XYNII from Trichoderma reesei with epoxyalkyl-xylose derivatives (Havukainen et al., 1996) have provided important information on substrate binding. Family G/11 xylanases show clear amino acid homology and thus have a common fold. However, variations in their functional properties, such as catalytic activity, substrate cleaving patterns, pH optima and thermostabilities, exist.
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structural and functional properties of low molecular weight Endo 1 4 β xylanases
Journal of Biotechnology, 1997Co-Authors: Anneli Torronen, Juha RouvinenAbstract:There are currently four crystal structures of low molecular weight Endo-1,4-beta-xylanases (E.C.3.2.1.8), i.e. family G/11 xylanases, available at the Brookhaven Data Bank: 2 xylanases from Trichoderma reesei (Torronen et al., 1994; Torronen and Rouvinen, 1995) and one from Bacillus circulans and another from Trichoderma harzianum (Campbell et al., 1993). They consist of two beta-sheets and one alpha-helix and have been described to resemble a partly-closed right hand. The catalytic residues are two conserved glutamate residues, which are located opposite to each other in an open active site cleft. The catalytic mechanism is thought to resemble that of the widely-studied enzyme lysozyme. The role of one glutamate is to act as an acid/base catalyst whereas the other is a nucleophile and stabilizes the reaction intermediate. Complex structures of partly-bound xylotetraose in mutated XYN from Bacillus circulans (Wakarchuck et al., 1994a) and three recently-obtained structures of XYNII from Trichoderma reesei with epoxyalkyl-xylose derivatives (Havukainen et al., 1996) have provided important information on substrate binding. Family G/11 xylanases show clear amino acid homology and thus have a common fold. However, variations in their functional properties, such as catalytic activity, substrate cleaving patterns, pH optima and thermostabilities, exist.
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structural comparison of two major Endo 1 4 xylanases from trichoderma reesei
Biochemistry, 1995Co-Authors: Anneli Torronen, Juha RouvinenAbstract:Three-dimensional structures of two major Endo-1,4-xylanases, XYNI and XYNII from Trichoderma reesei, have been determined by X-ray crystallography. The amino acid sequences of both enzymes are highly homologous (identity approximately 50%), and both XYNI and XYNII exist as a single domain that contains two mostly antiparallel beta-sheets which are packed against each other. The beta-sheet structure is twisted, forming a cleft where the active site is situated. Two glutamic acids in the cleft, Glu75 and Glu164 in XYNI as well as Glu86 and Glu177 in XYNII, are most likely involved in catalysis. Inspection of the structures reveals that the width of the active site cleft and the number of subsites are different in XYNI and XYNII. The active site is narrower in XYNI and probably contains only three subsites, whereas the number of subsites in XYNII is most likely five. Variations in the surroundings of catalytic residue Glu164XYNI/Glu177XYNII are thought to explain the pH optimum differences observed in XYNI and XYNII.
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three dimensional structure of Endo 1 4 beta xylanase ii from trichoderma reesei two conformational states in the active site
The EMBO Journal, 1994Co-Authors: Anneli Torronen, Anu Marjukka Harkki, Juha RouvinenAbstract:Abstract The three-dimensional structure of Endo-1,4-beta-xylanase II (XYNII) from Trichoderma reesei has been determined by X-ray diffraction techniques and refined to a conventional R-factor of 18.3% at 1.8 A resolution. The 190 amino acid length protein was found to exist as a single domain where the main chain folds to form two mostly antiparallel beta-sheets, which are packed against each other in parallel. The beta-sheet structure is twisted, forming a large cleft on one side of the molecule. The structure of XYNII resembles that of Bacillus 1,3-1,4-beta-glucanase. The cleft is an obvious suggestion for an active site, which has putative binding sites for at least four xylose residues. The catalytic residues are apparently the two glutamic acid residues (Glu86 and Glu177) in the middle of the cleft. One structure was determined at pH 5.0, corresponding to the pH optimum of XYNII. The second structure was determined at pH 6.5, where enzyme activity is reduced considerably. A clear structural change was observed, especially in the position of the side chain of Glu177. The observed conformational change is probably important for the mechanism of catalysis in XYNII.
T. N. Zvyagintseva - One of the best experts on this subject based on the ideXlab platform.
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Endo 1 4 fucoidanase from vietnamese marine mollusk lambis sp which producing sulphated fucooligosaccharides
Journal of Molecular Catalysis B-enzymatic, 2014Co-Authors: A. M. Zakharenko, M. I. Kusaykin, A. S. Silchenko, Pavel S. Dmitrenok, Roza V Menshova, Huynh Hoang Nhu Khanh, V V Isakov, T. N. ZvyagintsevaAbstract:Abstract The fucoidanase was isolated and purified from the digestive glands of the marine mollusk Lambis sp. The molecular mass of homogeneous enzyme as estimated by SDS electrophoresis was about 50 kDa. Optima of pH and temperature were at 4.9 and 37 °C, respectively. Its half-inactivation time was 20 min at 54 °C. The fucoidanase had a Km value of 1.3 mg ml−1 for the hydrolysis of fucoidan from Fucus evanescens. The fucoidanase catalysed the hydrolysis of 1→3;1→4-α- l -fucans from Fucus evanescens and Fucus vesiculosus, but not 1→3-α- l -fucan from Saccharina cichorioides. Native fucoidan from F. evanescens was hydrolysed weakly in contrast to desulphated fucoidan. Based on the analysis of substrate specificity and the structure of the reaction products the fucoidanase from Lambis sp. catalyzed hydrolysis of 1→4-bonds in a fucoidan molecule as Endo-enzyme.
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glycosidases of marine organisms
Biochemistry, 2013Co-Authors: V V Sova, A. M. Zakharenko, Svetlana N. Kovalchuk, Maria S. Pesentseva, T. N. ZvyagintsevaAbstract:This review discusses the catalytic properties, activity regulation, structure, and functions of O-glycoside hydrolases from marine organisms exemplified by Endo-1→3-β-D-glucanases of marine invertebrates.
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catalytic properties and amino acid sequence of Endo 1 3 β d glucanase from the marine mollusk tapes literata
Biochemistry, 2012Co-Authors: A. M. Zakharenko, V. V. Sova, M. I. Kusaykin, A. S. Silchenko, A. A. Belik, S. D. Anastyuk, V. A. Rasskazov, Svetlana N. Kovalchuk, T. N. ZvyagintsevaAbstract:A specific 1→3-β-D-glucanase with molecular mass 37 kDa was isolated in homogeneous state from crystalline style of the commercial marine mollusk Tapes literata. It exhibits maximal activity within the pH range from 4.5 to 7.5 at 45dgC. The 1→3-β-D-glucanase catalyzes hydrolysis of β-1→3 bonds in glucans as an Endoenzyme with retention of bond configuration, and it has transglycosylating activity. The K m for hydrolysis of laminaran is 0.25 mg/ml. The enzyme is classified as a glucan Endo-(1→3)-β-D-glucosidase (EC 3.2.1.39). The cDNA encoding this 1→3-β-D-glucanase from T. literata was sequenced, and the amino acid sequence of the enzyme was determined. The Endo-1→3-β-D-glucanase from T. literata was assigned to the 16th structural family (GHF 16) of O-glycoside hydrolases.
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Endo 1 3 β d glucanase gi from marine mollusk littorina sitkana amino acid sequence and esims ms estimated features of transglycosylation and hydrolysis reactions in comparison to analogous enzyme liv from pseudocardium sachalinensis
Journal of Molecular Catalysis B-enzymatic, 2012Co-Authors: Maria S. Pesentseva, V. V. Sova, M. I. Kusaykin, S. D. Anastyuk, V. A. Rasskazov, Svetlana N. Kovalchuk, T. N. ZvyagintsevaAbstract:Abstract The cDNA encoding the glucanase GI from Littorina sitkana (formerly named Littorina kurila ) was cloned and sequenced, and the enzyme was assigned to glycoside hydrolases family 16 (GHF16) on the basis of amino acid sequence similarity. Structural features of the products of transglycosylation reaction using 6-O-methyl-β- d -glucuronic acid as an acceptor were established. Using colisionally induced dissociation (CID) tandem electrospray ionization mass spectrometry (ESIMS/MS) it was shown that GI transfers the residues of glyconic parts of the substrate mainly at C3 and C4 positions of 6-O-methyl-β- d -glucuronic acid and strictly at C3 position of glucose residue. The semi-quantitative characteristics of simultaneously passing hydrolysis and transglycosylation reactions catalyzed by retaining Endo-(1→3)-β- d -glucanases GI from L. sitkana and LIV from Pseudocardium sachalinensis (formerly named Spisula sachalinensis ) have been obtained by ESIMS. Laminaran was used as a donor, while glycerol was employed as an acceptor. The significant distinctions of catalytic properties of LIV and GI were revealed.
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catalytic properties and mode of action of Endo 1 3 β d glucanase and β d glucosidase from the marine mollusk littorina kurila
Carbohydrate Research, 2008Co-Authors: Maria S. Pesentseva, V. V. Sova, M. I. Kusaykin, S. D. Anastyuk, T. N. ZvyagintsevaAbstract:Abstract A complex of the enzymes from the liver of the marine mollusk Littorina kurila that hydrolyzes laminaran was investigated. Two (1→3)-β- d -glucanases (G-I and G-II) were isolated. The molecular mass of G-I as estimated by gel-permeation chromatography and SDS–PAGE analysis was 32 and 40 kDa, respectively. The G-II molecular mass according to SDS–PAGE analysis was about 200 kDa. The pH optimum for both G-I and G-II was pH 5.4. The G-I had narrow substrate specificity and hydrolyzed only the (1→3)-β- d -glucosidic bonds in the mixed (1→3),(1→6)- and (1→3),(1→4)-β- d -glucans down to glucose and glucooligosaccharides. This enzyme acted with retention of the anomeric configuration and catalyzed a transglycosylation reaction. G-I was classified as the glucan Endo -(1→3)-β- d -glucosidase (EC 3.2.1.39). G-II exhibited both exo -glucanase and β- d -glucoside activities. This enzyme released from the laminaran glucose as a single product, but retained the anomeric center configuration and possessed transglycosylation activity. The hydrolysis rate of glucooligosaccharides by G-I decreased with an increase of the substrate’s degree of polymerization. In addition to (1→3)-β- d -glucanase activity, the enzyme had the ability to hydrolyze p -nitrophenyl β- d -glucoside and β- d -glucobioses: laminaribiose, gentiobiose, and cellobiose, with the rate ratio of 50:12:1. G-II may correspond to β- d -glucoside glucohydrolase (EC 3.2.1.21).