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T. N. Zvyagintseva - One of the best experts on this subject based on the ideXlab platform.

  • endo 1 4 fucoidanase from vietnamese Marine Mollusk lambis sp which producing sulphated fucooligosaccharides
    Journal of Molecular Catalysis B-enzymatic, 2014
    Co-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. Zvyagintseva
    Abstract:

    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.

  • a new arylsulfatase from the Marine Mollusk turbo chrysostomus
    Chemistry of Natural Compounds, 2012
    Co-Authors: M. S. Pesentseva, V. V. Sova, A. A. Kicha, Thomas Haertlé, Al Sil S Chenko, T. N. Zvyagintseva
    Abstract:

    A new arylsulfatase (EC 3.1.6.1) was isolated from the liver of the Marine Mollusk Turbo chrysostomus. The enzyme catalyzed hydrolysis of potassium p-nitrophenylsulfate, did not affect natural fucoidan, and catalyzed cleavage of sulphate in the C4 position of xylose included in carbohydrate chains of holothurian triterpene glycosides. Halistanol sulphate and glycosides from starfish that contained sulfates in the aglycon part of the molecule inhibited the activity of the arylsulfatase. Several holothurian glycosides in small concentrations (3.5–8 × 10–10 M) increased the enzyme activity. The arylsulfatase activity was maximal at pH 7. Its molecular weight was 35 kDa according to gel-filtration. The Michaelis constant (KM) for hydrolysis of p-nitrophenylsulfate was 10 mM. The inactivation half-life of the enzyme was 15 min at 55°C.

  • catalytic properties and amino acid sequence of endo 1 3 β d glucanase from the Marine Mollusk tapes literata
    Biochemistry, 2012
    Co-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. Zvyagintseva
    Abstract:

    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.

  • Catalytic properties and amino acid sequence of endo-1→3-β-D-glucanase from the Marine Mollusk Tapes literata
    Biochemistry (Moscow), 2012
    Co-Authors: A. M. Zakharenko, V. V. Sova, M. I. Kusaykin, S. N. Kovalchuk, A. S. Silchenko, A. A. Belik, S. D. Anastyuk, V. A. Rasskazov, T. N. Zvyagintseva
    Abstract:

    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.

  • A new arylsulfatase from the Marine Mollusk Turbo chrysostomus
    Chemistry of Natural Compounds, 2012
    Co-Authors: M. S. Pesentseva, V. V. Sova, Al S. Sil'chenko, A. A. Kicha, Thomas Haertlé, T. N. Zvyagintseva
    Abstract:

    A new arylsulfatase (EC 3.1.6.1) was isolated from the liver of the Marine Mollusk Turbo chrysostomus. The enzyme catalyzed hydrolysis of potassium p-nitrophenylsulfate, did not affect natural fucoidan, and catalyzed cleavage of sulphate in the C4 position of xylose included in carbohydrate chains of holothurian triterpene glycosides. Halistanol sulphate and glycosides from starfish that contained sulfates in the aglycon part of the molecule inhibited the activity of the arylsulfatase. Several holothurian glycosides in small concentrations (3.5-8 x 10(-10) M) increased the enzyme activity. The arylsulfatase activity was maximal at pH 7. Its molecular weight was 35 kDa according to gel-filtration. The Michaelis constant (K-M) for hydrolysis of p-nitrophenylsulfate was 10 mM. The inactivation half-life of the enzyme was 15 min at 55A degrees C.

V. V. Sova - One of the best experts on this subject based on the ideXlab platform.

  • a new arylsulfatase from the Marine Mollusk turbo chrysostomus
    Chemistry of Natural Compounds, 2012
    Co-Authors: M. S. Pesentseva, V. V. Sova, A. A. Kicha, Thomas Haertlé, Al Sil S Chenko, T. N. Zvyagintseva
    Abstract:

    A new arylsulfatase (EC 3.1.6.1) was isolated from the liver of the Marine Mollusk Turbo chrysostomus. The enzyme catalyzed hydrolysis of potassium p-nitrophenylsulfate, did not affect natural fucoidan, and catalyzed cleavage of sulphate in the C4 position of xylose included in carbohydrate chains of holothurian triterpene glycosides. Halistanol sulphate and glycosides from starfish that contained sulfates in the aglycon part of the molecule inhibited the activity of the arylsulfatase. Several holothurian glycosides in small concentrations (3.5–8 × 10–10 M) increased the enzyme activity. The arylsulfatase activity was maximal at pH 7. Its molecular weight was 35 kDa according to gel-filtration. The Michaelis constant (KM) for hydrolysis of p-nitrophenylsulfate was 10 mM. The inactivation half-life of the enzyme was 15 min at 55°C.

  • catalytic properties and amino acid sequence of endo 1 3 β d glucanase from the Marine Mollusk tapes literata
    Biochemistry, 2012
    Co-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. Zvyagintseva
    Abstract:

    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.

  • Catalytic properties and amino acid sequence of endo-1→3-β-D-glucanase from the Marine Mollusk Tapes literata
    Biochemistry (Moscow), 2012
    Co-Authors: A. M. Zakharenko, V. V. Sova, M. I. Kusaykin, S. N. Kovalchuk, A. S. Silchenko, A. A. Belik, S. D. Anastyuk, V. A. Rasskazov, T. N. Zvyagintseva
    Abstract:

    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.

  • A new arylsulfatase from the Marine Mollusk Turbo chrysostomus
    Chemistry of Natural Compounds, 2012
    Co-Authors: M. S. Pesentseva, V. V. Sova, Al S. Sil'chenko, A. A. Kicha, Thomas Haertlé, T. N. Zvyagintseva
    Abstract:

    A new arylsulfatase (EC 3.1.6.1) was isolated from the liver of the Marine Mollusk Turbo chrysostomus. The enzyme catalyzed hydrolysis of potassium p-nitrophenylsulfate, did not affect natural fucoidan, and catalyzed cleavage of sulphate in the C4 position of xylose included in carbohydrate chains of holothurian triterpene glycosides. Halistanol sulphate and glycosides from starfish that contained sulfates in the aglycon part of the molecule inhibited the activity of the arylsulfatase. Several holothurian glycosides in small concentrations (3.5-8 x 10(-10) M) increased the enzyme activity. The arylsulfatase activity was maximal at pH 7. Its molecular weight was 35 kDa according to gel-filtration. The Michaelis constant (K-M) for hydrolysis of p-nitrophenylsulfate was 10 mM. The inactivation half-life of the enzyme was 15 min at 55A degrees C.

  • 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, 2008
    Co-Authors: Maria S. Pesentseva, V. V. Sova, M. I. Kusaykin, S. D. Anastyuk, T. N. Zvyagintseva
    Abstract:

    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).

A. M. Zakharenko - One of the best experts on this subject based on the ideXlab platform.

  • endo 1 4 fucoidanase from vietnamese Marine Mollusk lambis sp which producing sulphated fucooligosaccharides
    Journal of Molecular Catalysis B-enzymatic, 2014
    Co-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. Zvyagintseva
    Abstract:

    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.

  • catalytic properties and amino acid sequence of endo 1 3 β d glucanase from the Marine Mollusk tapes literata
    Biochemistry, 2012
    Co-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. Zvyagintseva
    Abstract:

    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.

  • Catalytic properties and amino acid sequence of endo-1→3-β-D-glucanase from the Marine Mollusk Tapes literata
    Biochemistry (Moscow), 2012
    Co-Authors: A. M. Zakharenko, V. V. Sova, M. I. Kusaykin, S. N. Kovalchuk, A. S. Silchenko, A. A. Belik, S. D. Anastyuk, V. A. Rasskazov, T. N. Zvyagintseva
    Abstract:

    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.

Guido Cimino - One of the best experts on this subject based on the ideXlab platform.

  • structure and synthesis of a unique isonitrile lipid isolated from the Marine Mollusk actinocyclus papillatus
    Organic Letters, 2011
    Co-Authors: Emiliano Manzo, Marianna Carbone, Ernesto Mollo, Yue-wei Guo, Guido Cimino, Maria Letizia Ciavatta, Carlo Irace, Antonio Di Pascale, Margherita Gavagnin
    Abstract:

    The first chemical study of an Actinocyclidae nudibranch, Actinocyclus papillatus, resulted in the isolation of (-)-actisonitrile (1), a lipid based on a 1,3-propanediol ether skeleton. The structure was established by spectroscopic methods, whereas the absolute configuration of the chiral center was determined by comparing the optical properties of natural actisonitrile with those of (+)- and (-)-synthetic enantiomers, opportunely prepared. Both (-)- and (+)-actisonitrile were tested in preliminary in vitro cytotoxicity bioassays on tumor and nontumor mammalian cells.

  • Synthesis and absolute stereochemistry of Marine nor-sesquiterpene austrodoric acid
    Tetrahedron: Asymmetry, 2004
    Co-Authors: Veaceslav Kulcitki, Marianna Carbone, Margherita Gavagnin, Nicon Ungur, Guido Cimino
    Abstract:

    An enantiospecific synthesis of the nor-sesquiterpene austrodoric acid 1, recently isolated from an Antarctic Marine Mollusk, has been achieved. The synthetic strategy was based on the ring contraction of a suitable homo-drimanic epoxide 3, easily obtained from commercial (+)-sclareolide 4. The absolute configuration of natural austrodoric acid, not determined previously, has been now established by analyzing the CD profile of synthetic 1, which was the same as the natural compound.

M. I. Kusaykin - One of the best experts on this subject based on the ideXlab platform.

  • endo 1 4 fucoidanase from vietnamese Marine Mollusk lambis sp which producing sulphated fucooligosaccharides
    Journal of Molecular Catalysis B-enzymatic, 2014
    Co-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. Zvyagintseva
    Abstract:

    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.

  • catalytic properties and amino acid sequence of endo 1 3 β d glucanase from the Marine Mollusk tapes literata
    Biochemistry, 2012
    Co-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. Zvyagintseva
    Abstract:

    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.

  • Catalytic properties and amino acid sequence of endo-1→3-β-D-glucanase from the Marine Mollusk Tapes literata
    Biochemistry (Moscow), 2012
    Co-Authors: A. M. Zakharenko, V. V. Sova, M. I. Kusaykin, S. N. Kovalchuk, A. S. Silchenko, A. A. Belik, S. D. Anastyuk, V. A. Rasskazov, T. N. Zvyagintseva
    Abstract:

    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.

  • Inhibition of adherence of Corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases from Marine hydrobiontes
    Biomeditsinskaya Khimiya, 2010
    Co-Authors: I. D. Makarenkova, M. I. Kusaykin, Tatyana N. Zvyagintseva, Irina Y. Bakunina, Yuliya V. Burtseva, Larissa A. Balabanova, N. N. Besednova, V. A. Rasskazov
    Abstract:

    A possibility of adhesion inhibition of Corynebacterium diphtheriae to human buccal epithelium by glycoside hydrolases of Marine hydrobiontes was investigated using α-galactosidase from Marine bacterium Pseudoalteromonas sp. КММ 701, total enzyme preparation and β-1,3-glucanase from Marine fungi Chaetomium, total enzyme preparation and β-1,3-glucanase from Marine Mollusk Littorina kurila, and total enzyme preparation from crystalline style of Marine Mollusk Spisula sachalinensis were used. The enzymes were added to test-tubes containing buccal epithelial cells and/or the toxigenic bacterial strain C. diphtheriae №1129, v. gravis. All the investigated enzymes were able to abort C. diphtheriae adherence to human buccal epithelocytes. Inhibition of adhesion was more pronounced in the case of treatment of epithelocytes with highly purified enzymes of Marine hydrobiontes in comparison with total enzyme preparations. The significant inhibition of C. diphtheriae adhesion was observed when the enzymes were added to the epithelocytes with the attached microorganisms.The results obtained show that glycoside hydrolases of Marine hydrobiontes degrade any carbohydrates expressed on cell surface of bacterium or human buccal epithelocytes, impair unique lectin-carbohydrate interaction and prevent the adhesion.

  • 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, 2008
    Co-Authors: Maria S. Pesentseva, V. V. Sova, M. I. Kusaykin, S. D. Anastyuk, T. N. Zvyagintseva
    Abstract:

    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).