title: Analysis of Domain Architecture and Phylogenetics of Family 2 Glycoside Hydrolases (GH2).
abstract: In this work we report a detailed analysis of the topology and phylogenetics of family 2 glycoside hydrolases (GH2). We distinguish five topologies or domain architectures based on the presence and distribution of protein domains defined in Pfam and Interpro databases. All of them share a central TIM barrel (catalytic module) with two β-sandwich domains (non-catalytic) at the N-terminal end, but differ in the occurrence and nature of additional non-catalytic modules at the C-terminal region. Phylogenetic analysis was based on the sequence of the Pfam Glyco_hydro_2_C catalytic module present in most GH2 proteins. Our results led us to propose a model in which evolutionary diversity of GH2 enzymes is driven by the addition of different non-catalytic domains at the C-terminal region. This model accounts for the divergence of β-galactosidases from β-glucuronidases, the diversification of β-galactosidases with different transglycosylation specificities, and the emergence of bicistronic β-galactosidases. This study also allows the identification of groups of functionally uncharacterized protein sequences with potential biotechnological interest.
authors.affiliation: Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain.
authors.forename: David
authors.initials: D
authors.lastname: Talens-Perales
authors.affiliation: Center for Bioinformatics, University of Tübingen, Tübingen, Germany.
authors.forename: Anna
authors.initials: A
authors.lastname: Górska
authors.affiliation: Center for Bioinformatics, University of Tübingen, Tübingen, Germany.
authors.forename: Daniel H
authors.initials: DH
authors.lastname: Huson
authors.affiliation: Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain.
authors.forename: Julio
authors.initials: J
authors.lastname: Polaina
authors.affiliation: Instituto de Agroquímica y Tecnología de Alimentos, CSIC, Paterna, Valencia, Spain.
authors.forename: Julia
authors.identifier: http://orcid.org/0000-0001-7893-3423
authors.initials: J
authors.lastname: Marín-Navarro
mesh_terms: D000595:Amino Acid Sequence; D001419:Bacteria / Q000201:enzymology / Q000235:genetics; D020134:Catalytic Domain / Q000235:genetics; D005966:Glucuronidase / Q000737:chemistry / Q000235:genetics; D006026:Glycoside Hydrolases / Q000737:chemistry / Q000235:genetics*; D006031:Glycosylation; D062105:Molecular Docking Simulation; D010802:Phylogeny; D013379:Substrate Specificity; D001616:beta-Galactosidase / Q000737:chemistry / Q000235:genetics
chemical_list: D006026:Glycoside Hydrolases; D001616:beta-Galactosidase; D005966:Glucuronidase