title: Structural basis of the substrate specificity of the FPOD/FAOD family revealed by fructosyl peptide oxidase from Eupenicillium terrenum.
abstract: The FAOD/FPOD family of proteins has the potential to be useful for the longterm detection of blood glucose levels in diabetes patients. A bottleneck for this application is to find or engineer a FAOD/FPOD family enzyme that is specifically active towards α-fructosyl peptides but is inactive towards other types of glycated peptides. Here, the crystal structure of fructosyl peptide oxidase from Eupenicillium terrenum (EtFPOX) is reported at 1.9 Å resolution. In contrast to the previously reported structure of amadoriase II, EtFPOX has an open substrate entrance to accommodate the large peptide substrate. The functions of residues critical for substrate selection are discussed based on structure comparison and sequence alignment. This study reveals the first structural details of group I FPODs that prefer α-fructosyl substrates and could provide significant useful information for uncovering the mechanism of substrate specificity of FAOD/FPODs and guidance towards future enzyme engineering for diagnostic purposes.
authors: Key Laboratory of RNA, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, People's Republic of China.
authors: Weiqiong
authors: W
authors: Gan
authors: Key Laboratory of RNA, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, People's Republic of China.
authors: Feng
authors: F
authors: Gao
authors: Center for Chemical Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300457, People's Republic of China.
authors: Keke
authors: K
authors: Xing
authors: Key Laboratory of RNA, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, People's Republic of China.
authors: Minze
authors: M
authors: Jia
authors: Center for Chemical Biology, Tianjin Institute of Industrial Biotechnology, Chinese Academy of Sciences, Tianjin 300457, People's Republic of China.
authors: Haiping
authors: H
authors: Liu
authors: Key Laboratory of RNA, Institute of Biophysics, Chinese Academy of Sciences, 15 Datun Road, Beijing 100101, People's Republic of China.
authors: Weimin
authors: W
authors: Gong
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000737:chemistry* / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D055324:Eupenicillium / Q000201:enzymology*; D006801:Humans; D008969:Molecular Sequence Data; D017433:Protein Structure, Secondary; D017434:Protein Structure, Tertiary; D013379:Substrate Specificity / Q000502:physiology
chemical_list: D000594:Amino Acid Oxidoreductases; C103012:amadoriase; C520096:fructosyl-peptide oxidase
keywords: Eupenicillium terrenum; FAOD/FPOD family; fructosyl peptide oxidase