title: Phylogenetic analysis and substrate specificity of GH2 β-mannosidases from Aspergillus species.
abstract: Phylogenetic analysis of glycoside hydrolase family 2 including Aspergillus sequences and characterised β-mannosidases from other organisms, clusters putative Aspergillus β-mannosidases in two distinct clades (A and B). Aspergillus species have at least one paralog in each of the two clades. It appears that clade A members are extracellular and clade B members intracellular. Substrate specificity analysis of MndA of Aspergillus niger (clade A) and MndB of Aspergillus nidulans (clade B) show that MndB, in contrast to MndA, does not hydrolyse polymeric mannan and has probably evolved to hydrolyse small unbranched β-mannosides like mannobiose. A 3D-model of MndB provides further insight.
authors.affiliation: Department of Biochemistry and Structural Biology, Lund University, Lund S-22100, Sweden.
authors.forename: Sumitha K
authors.initials: SK
authors.lastname: Reddy
authors.forename: Anna
authors.initials: A
authors.lastname: Rosengren
authors.forename: Sylvia
authors.initials: S
authors.lastname: Klaubauf
authors.forename: Tejas
authors.initials: T
authors.lastname: Kulkarni
authors.forename: Eva Nordberg
authors.initials: EN
authors.lastname: Karlsson
authors.forename: Ronald P
authors.initials: RP
authors.lastname: de Vries
authors.forename: Henrik
authors.initials: H
authors.lastname: Stålbrand
mesh_terms: D001233:Aspergillus nidulans / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D001234:Aspergillus niger / Q000201:enzymology* / Q000378:metabolism; D005656:Fungal Proteins / Q000235:genetics* / Q000378:metabolism*; D006868:Hydrolysis; D008351:Mannans / Q000378:metabolism; D010802:Phylogeny; D013379:Substrate Specificity; D044902:beta-Mannosidase / Q000235:genetics* / Q000378:metabolism*
chemical_list: D005656:Fungal Proteins; D008351:Mannans; C014647:mannobiose; D044902:beta-Mannosidase
keywords: Aspergillus β-mannosidase homolog; Fine-tuned substrate specificity; Glycoside hydrolase family 2; Intracellular and extracellular β-mannosidase; Phylogenetic analysis