title: Beta-helical catalytic domains in glycoside hydrolase families 49, 55 and 87: domain architecture, modelling and assignment of catalytic residues.
abstract: X-ray crystallography and bioinformatics studies reveal a tendency for the right-handed beta-helix domain architecture to be associated with carbohydrate binding proteins. Here we demonstrate the presence of catalytic beta-helix domains in glycoside hydrolase (GH) families 49, 55 and 87 and provide evidence for their sharing a common evolutionary ancestor with two structurally characterized GH families, numbers 28 and 82. This domain assignment helps assign catalytic residues to each family. Further analysis of domain architecture reveals the association of carbohydrate binding modules with catalytic GH beta-helices, as well as an unexpected pair of beta-helix domains in GH family 55.
authors.affiliation: Embrapa Genetic Resources and Biotechnology, Cenargen/Embrapa, S.A.I.N. Parque Rural, Final W5, Asa Norte, 70770-900 Brasília DF, Brazil. daniel@cenargen.embrapa.br
authors.forename: Daniel J
authors.initials: DJ
authors.lastname: Rigden
authors.forename: Octávio L
authors.initials: OL
authors.lastname: Franco
mesh_terms: D000595:Amino Acid Sequence; D020134:Catalytic Domain; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000378:metabolism*; D008958:Models, Molecular; D008969:Molecular Sequence Data; D011487:Protein Conformation; D017386:Sequence Homology, Amino Acid
chemical_list: D006026:Glycoside Hydrolases