title: Glycine residues provide flexibility for enzyme active sites.
abstract: The high resolution refined structures of 23 enzymes were analyzed to determine the properties of amino acids involved in active site regions. These regions were found to be rich in G-X-Y or Y-X-G oligopeptides, where X and Y are polar and non-polar residues, respectively, that are small and with low polarity. Other regions of the enzyme molecules have significantly fewer of these sequences. These features suggest that glycine residues may provide flexibility necessary for enzyme active sites to change conformation, and the G-X-Y or Y-X-G oligopeptides may be a motif for the formation of enzyme active sites.
authors.affiliation: Institute of Microbiology, National Laboratory of Microbial Technology, Shandong University, Jinan 250100, China.
authors.forename: B X
authors.initials: BX
authors.lastname: Yan
authors.forename: Y Q
authors.initials: YQ
authors.lastname: Sun
mesh_terms: D000595:Amino Acid Sequence; D001665:Binding Sites; D018360:Crystallography, X-Ray; D004798:Enzymes / Q000737:chemistry*; D005998:Glycine; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D013329:Structure-Activity Relationship; D013482:Superoxide Dismutase / Q000737:chemistry
chemical_list: D004798:Enzymes; D013482:Superoxide Dismutase; D005998:Glycine