title: Baculovirus envelope protein ODV-E66 is a novel chondroitinase with distinct substrate specificity.
abstract: Chondroitin sulfate is a linear polysaccharide of alternating D-glucuronic acid and N-acetyl-D-galactosamine residues with sulfate groups at various positions of the sugars. It interacts with and regulates cytokine and growth factor signal transduction, thus influencing development, organ morphogenesis, inflammation, and infection. We found chondroitinase activity in medium conditioned by baculovirus-infected insect cells and identified a novel chondroitinase. Sequence analysis revealed that the enzyme was a truncated form of occlusion-derived virus envelope protein 66 (ODV-E66) of Autographa californica nucleopolyhedrovirus. The enzyme was a novel chondroitin lyase with distinct substrate specificity. The enzyme was active over a wide range of pH (pH 4-9) and temperature (30-60 °C) and was unaffected by divalent metal ions. The ODV-E66 truncated protein digested chondroitin most efficiently followed by chondroitin 6-sulfate. It degraded hyaluronan to a minimal extent but did not degrade dermatan sulfate, heparin, and N-acetylheparosan. Further analysis using chemo-enzymatically synthesized substrates revealed that the enzyme specifically acted on glucuronate residues in non-sulfated and chondroitin 6-sulfate structures but not in chondroitin 4-sulfate structures. These results suggest that this chondroitinase is useful for detailed structural and compositional analysis of chondroitin sulfate, preparation of specific chondroitin oligosaccharides, and study of baculovirus infection mechanism.
authors.affiliation: Institute for Molecular Science of Medicine, Aichi Medical University, Yazako, Nagakute, Aichi 480-1195, Japan. Electronic address: nsugiura@aichi-med-u.ac.jp.
authors.forename: Nobuo
authors.initials: N
authors.lastname: Sugiura
authors.affiliation: Institute for Molecular Science of Medicine, Aichi Medical University, Yazako, Nagakute, Aichi 480-1195, Japan.
authors.forename: Yuka
authors.initials: Y
authors.lastname: Setoyama
authors.affiliation: Institute for Molecular Science of Medicine, Aichi Medical University, Yazako, Nagakute, Aichi 480-1195, Japan.
authors.forename: Mie
authors.initials: M
authors.lastname: Chiba
authors.affiliation: Research Complex for the Medicine Frontiers, Aichi Medical University, Yazako, Nagakute, Aichi 480-1195, Japan.
authors.forename: Koji
authors.initials: K
authors.lastname: Kimata
authors.affiliation: Institute for Molecular Science of Medicine, Aichi Medical University, Yazako, Nagakute, Aichi 480-1195, Japan.
authors.forename: Hideto
authors.initials: H
authors.lastname: Watanabe
mesh_terms: D000818:Animals; D036022:Capsid Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D002413:Cations, Divalent / Q000737:chemistry / Q000378:metabolism; D002810:Chondroitinases and Chondroitin Lyases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D006820:Hyaluronic Acid / Q000737:chemistry / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D017924:Nucleopolyhedroviruses / Q000201:enzymology* / Q000235:genetics; D018411:Spodoptera; D013379:Substrate Specificity / Q000502:physiology
chemical_list: D036022:Capsid Proteins; D002413:Cations, Divalent; D006820:Hyaluronic Acid; D002810:Chondroitinases and Chondroitin Lyases