6F72

Crystal structure of VAO-type flavoprotein MtVAO615 at pH 7.5 from Myceliophthora thermophila C1

Summary for 6F72

• Entry DOI: 10.2210/pdb6f72/pdb
• Related: 6F73 6F74
• Descriptor: MtVAO615, 2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, beta-D-mannopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose-(1-4)-2-acetamido-2-deoxy-beta-D-glucopyranose, ... (6 entities in total)
• Functional Keywords: flavoprotein, vao-type, fad, oxidoreductase
• Biological source: Myceliophthora thermophila (strain ATCC 42464 / BCRC 31852 / DSM 1799) (Sporotrichum thermophile)
• Total number of polymer chains: 1
• Total formula weight: 64908.84

Authors

Rozeboom, H.J.,Fraaije, M.W. (deposition date: 2017-12-07, release date: 2018-01-10, Last modification date: 2024-11-06)

Primary citation

Ferrari, A.R.,Rozeboom, H.J.,Vugts, A.S.C.,Koetsier, M.J.,Floor, R.,Fraaije, M.W.
Characterization of Two VAO-Type Flavoprotein Oxidases from Myceliophthora thermophila.
Molecules, 23:-, 2018

PubMed Abstract: The VAO flavoprotein family consists mostly of oxidoreductases harboring a covalently linked flavin cofactor. The linkage can be either monocovalent at position 8 with a histidine or tyrosine or bicovalent at position 8 with a histidine and at position 6 with a cysteine. Bicovalently bound flavoproteins show a preference for bulkier substrates such as oligosaccharides or secondary metabolites. The genome of the thermophilic fungus C1 was found to be rich in genes encoding putative covalent VAO-type flavoproteins. Enzymes from this fungus have the advantage of being rather thermostable and homologous overexpression in C1 is feasible. Recently we discovered a new and VAO-type carbohydrate oxidase from this fungus: xylooligosaccharide oxidase. In this study, two other putative VAO-type oxidases, protein sequence XP_003663615 (MtVAO615) and XP_003665713 (MtVAO713), were expressed in C1, purified and characterized. Enzyme MtVAO615 was found to contain a bicovalently bound FAD, while enzyme MtVAO713 contained a monocovalent histidyl-bound FAD. The crystal structures of both proteins were obtained which revealed atypical active site architectures. It could be experimentally verified that both proteins, when reduced, rapidly react with molecular oxygen, a hallmark of flavoprotein oxidases. A large panel of alcohols, including carbohydrates, steroids and secondary alcohols were tested as potential substrates. For enzyme MtVAO713 low oxidase activity was discovered towards ricinoleic acid.

PubMed: 29303991
DOI: 10.3390/molecules23010111

Experimental method

X-RAY DIFFRACTION (2 Å)