title: Crystal Structure of Amylomaltase from Corynebacterium glutamicum.
abstract: Amylomaltase is an essential enzyme in maltose utilization and maltodextrin metabolism, and it has been industrially used for the production of cyclodextrin and modification of starch. We determined the crystal structure of amylomaltase from Corynebacterium glutamicum (CgAM) at a resolution of 1.7 Å. Although CgAM forms a dimer without NaCl, it exists as a monomer in physiological concentration of NaCl. CgAM is composed of N- and C-terminal domains, which can be further divided into two and four subdomains, respectively. It exhibits a unique structural feature at the functionally unknown N-domain and also shows two striking differences at the C-domain compared to other amylomaltases. These differences at extended edge of the substrate-binding site might affect substrate specificity for large cyclodextrin formation. The bis-tris methane and sulfate molecules bound at the substrate-binding site of our current structure mimic the binding of the hydroxyl groups of glucose bound at subsites -1 and -2, respectively.
authors.affiliation: Structural and Molecular Biology Laboratory, School of Life Sciences and Biotechnology, Kyungpook National University , Daehak-ro 80, Buk-ku, Daegu 702-701, Republic of Korea.
authors.forename: Seongjoon
authors.initials: S
authors.lastname: Joo
authors.affiliation: Structural and Molecular Biology Laboratory, School of Life Sciences and Biotechnology, Kyungpook National University , Daehak-ro 80, Buk-ku, Daegu 702-701, Republic of Korea.|School of Nano-Bioscience and Chemical Engineering, Ulsan National Institute of Science and Technology (UNIST) , Ulsan, 689-798, Republic of Korea.
authors.forename: Sangwoo
authors.initials: S
authors.lastname: Kim
authors.affiliation: Structural and Molecular Biology Laboratory, School of Life Sciences and Biotechnology, Kyungpook National University , Daehak-ro 80, Buk-ku, Daegu 702-701, Republic of Korea.
authors.forename: Hogyun
authors.initials: H
authors.lastname: Seo
authors.affiliation: Structural and Molecular Biology Laboratory, School of Life Sciences and Biotechnology, Kyungpook National University , Daehak-ro 80, Buk-ku, Daegu 702-701, Republic of Korea.
authors.forename: Kyung-Jin
authors.initials: KJ
authors.lastname: Kim
mesh_terms: D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D048230:Corynebacterium glutamicum / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics; D018360:Crystallography, X-Ray; D006004:Glycogen Debranching Enzyme System / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism; D008958:Models, Molecular; D008969:Molecular Sequence Data; D000072417:Protein Domains; D016415:Sequence Alignment; D013379:Substrate Specificity
chemical_list: D001426:Bacterial Proteins; D006004:Glycogen Debranching Enzyme System; C020569:4 alpha-glucanotransferase
keywords: Corynebacterium glutamicum; amylomaltase; maltodextrin; maltose