Publications

• Beta-1,3-galactosyl-N-acetylhexosamine phosphorylase from Bifidobacterium bifidum DSM 20082: characterization, partial purification and relation to mucin degradation.

  Derensy-Dron D., Krzewinski F., Brassart C., Bouquelet S.

  A new enzyme has been characterized in a cell-free extract of Bifidobacterium bifidum that catalysed the reversible phosphorolytic cleavage of beta-1,3-galacto-oligosaccharides. In the presence of Pi, the phosphorolysis reaction was favoured and was accompanied by a Walden reaction. Cleavage of th ... >> More

  A new enzyme has been characterized in a cell-free extract of Bifidobacterium bifidum that catalysed the reversible phosphorolytic cleavage of beta-1,3-galacto-oligosaccharides. In the presence of Pi, the phosphorolysis reaction was favoured and was accompanied by a Walden reaction. Cleavage of the beta-glycosidic linkage gave an alpha-galactoside derivative (alpha-D-galactose 1-phosphate). The enzyme possesses a high specificity for beta-D-galactosido-(1, 3)-N-acetylglucosamine and beta-D-galactosido-(1, 3)-N-acetylgalactosamine. This purified intracellular enzyme had an estimated molecular mass of 140 kDa. The galactophosphorolytic activity on disaccharides was optimal at pH 6-6.5 and the reverse reaction was optimal at pH 5.5-6. The temperature optimum for phosphorolysis and the reverse reaction was approx. 50-55 degrees C. This enzyme is of particular interest in degrading some beta-D-Gal(1, 3) linkages and should be classified as EC 2.4.1.-. << Less

  Biotechnol Appl Biochem 29:3-10(1999) [PubMed] [EuropePMC]

• The crystal structure of galacto-N-biose/lacto-N-biose I phosphorylase: a large deformation of a TIM barrel scaffold.

  Hidaka M., Nishimoto M., Kitaoka M., Wakagi T., Shoun H., Fushinobu S.

  Galacto-N-biose/lacto-N-biose I phosphorylase (GLNBP) from Bifidobacterium longum, a key enzyme for intestinal growth, phosphorolyses galacto-N-biose and lacto-N-biose I with anomeric inversion. GLNBP homologues are often found in human pathogenic and commensal bacteria, and their substrate specif ... >> More

  Galacto-N-biose/lacto-N-biose I phosphorylase (GLNBP) from Bifidobacterium longum, a key enzyme for intestinal growth, phosphorolyses galacto-N-biose and lacto-N-biose I with anomeric inversion. GLNBP homologues are often found in human pathogenic and commensal bacteria, and their substrate specificities potentially define the nutritional acquisition ability of these microbes in their habitat. We report the crystal structures of GLNBP in five different ligand-binding forms. This is the first three-dimensional structure of glycoside hydrolase (GH) family 112. The GlcNAc- and GalNAc-bound forms provide structural insights into distinct substrate preferences of GLNBP and its homologues from pathogens. The catalytic domain consists of a partially broken TIM barrel fold that is structurally similar to a thermophilic beta-galactosidase, strongly supporting the current classification of GLNBP homologues as one of the GH families. Anion binding induces a large conformational change by rotating a half-unit of the barrel. This is an unusual example of molecular adaptation of a TIM barrel scaffold to substrates. << Less

  J. Biol. Chem. 284:7273-7283(2009) [PubMed] [EuropePMC]

• Novel putative galactose operon involving lacto-N-biose phosphorylase in Bifidobacterium longum.

  Kitaoka M., Tian J., Nishimoto M.

  A lacto-N-biose phosphorylase (LNBP) was purified from the cell extract of Bifidobacterium bifidum. Its N-terminal and internal amino acid sequences were homologous with those of the hypothetical protein of Bifidobacterium longum NCC2705 encoded by the BL1641 gene. The homologous gene of the type ... >> More

  A lacto-N-biose phosphorylase (LNBP) was purified from the cell extract of Bifidobacterium bifidum. Its N-terminal and internal amino acid sequences were homologous with those of the hypothetical protein of Bifidobacterium longum NCC2705 encoded by the BL1641 gene. The homologous gene of the type strain B. longum JCM1217, lnpA, was expressed in Escherichia coli to confirm that it encoded LNBP. No significant identity was found with any proteins with known function, indicating that LNBP should be classified in a new family. The lnpA gene is located in a novel putative operon for galactose metabolism that does not contain a galactokinase gene. The operon seems to be involved in intestinal colonization by bifidobacteria mediated by metabolism of mucin sugars. In addition, it may also resolve the question of the nature of the bifidus factor in human milk as the lacto-N-biose structure found in milk oligosaccharides. << Less

  Appl. Environ. Microbiol. 71:3158-3162(2005) [PubMed] [EuropePMC]

• Characterization of three beta-galactoside phosphorylases from Clostridium phytofermentans: discovery of d-galactosyl-beta1->4-l-rhamnose phosphorylase.

  Nakajima M., Nishimoto M., Kitaoka M.

  We characterized three d-galactosyl-beta1-->3-N-acetyl-d-hexosamine phosphorylase (EC 2.4.1.211) homologs from Clostridium phytofermentans (Cphy0577, Cphy1920, and Cphy3030 proteins). Cphy0577 and Cphy3030 proteins exhibited similar activity on galacto-N-biose (GNB; d-Gal-beta1-->3-d-GalNAc) and l ... >> More

  We characterized three d-galactosyl-beta1-->3-N-acetyl-d-hexosamine phosphorylase (EC 2.4.1.211) homologs from Clostridium phytofermentans (Cphy0577, Cphy1920, and Cphy3030 proteins). Cphy0577 and Cphy3030 proteins exhibited similar activity on galacto-N-biose (GNB; d-Gal-beta1-->3-d-GalNAc) and lacto-N-biose I (LNB; d-Gal-beta1-->3-d-GlcNAc), thus indicating that they are d-galactosyl-beta1-->3-N-acetyl-d-hexosamine phosphorylases, subclassified as GNB/LNB phosphorylase. In contrast, Cphy1920 protein phosphorolyzed neither GNB nor LNB. It showed the highest activity with l-rhamnose as the acceptor in the reverse reaction using alpha-d-galactose 1-phosphate as the donor. The reaction product was d-galactosyl-beta1-->4-l-rhamnose. The enzyme also showed activity on l-mannose, l-lyxose, d-glucose, 2-deoxy-d-glucose, and d-galactose in this order. When d-glucose derivatives were used as acceptors, reaction products were beta-1,3-galactosides. Kinetic parameters of phosphorolytic activity on d-galactosyl-beta1-->4-l-rhamnose were k(cat) = 45 s(-1) and K(m) = 7.9 mm, thus indicating that these values are common among other phosphorylases. We propose d-galactosyl-beta1-->4-l-rhamnose phosphorylase as the name for Cphy1920 protein. << Less

  J. Biol. Chem. 284:19220-19227(2009) [PubMed] [EuropePMC]

  This publication is cited by 1 other entry.