title: A survey of genes encoding H2O2-producing GMC oxidoreductases in 10 Polyporales genomes.
abstract: The genomes of three representative Polyporales (Bjerkandera adusta, Phlebia brevispora and a member of the Ganoderma lucidum complex) recently were sequenced to expand our knowledge on the diversity and distribution of genes involved in degradation of plant polymers in this Basidiomycota order, which includes most wood-rotting fungi. Oxidases, including members of the glucose-methanol-choline (GMC) oxidoreductase superfamily, play a central role in the above degradative process because they generate extracellular H2O2 acting as the ultimate oxidizer in both white-rot and brown-rot decay. The survey was completed by analyzing the GMC genes in the available genomes of seven more species to cover the four Polyporales clades. First, an in silico search for sequences encoding members of the aryl-alcohol oxidase, glucose oxidase, methanol oxidase, pyranose oxidase, cellobiose dehydrogenase and pyranose dehydrogenase families was performed. The curated sequences were subjected to an analysis of their evolutionary relationships, followed by estimation of gene duplication/reduction history during fungal evolution. Second, the molecular structures of the near one hundred GMC oxidoreductases identified were modeled to gain insight into their structural variation and expected catalytic properties. In contrast to ligninolytic peroxidases, whose genes are present in all white-rot Polyporales genomes and absent from those of brown-rot species, the H2O2-generating oxidases are widely distributed in both fungal types. This indicates that the GMC oxidases provide H2O2 for both ligninolytic peroxidase activity (in white-rot decay) and Fenton attack on cellulose (in brown-rot decay), after the transition between both decay patterns in Polyporales occurred.
authors: Departamento de Bioquímica y Biología Molecular y Celular and BIFI, Universidad de Zaragoza, E-50009 Zaragoza, Spain.
authors: Patricia
authors: P
authors: Ferreira
authors: Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain.
authors: Juan
authors: J
authors: Carro
authors: Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain.
authors: Ana
authors: A
authors: Serrano
authors: Centro de Investigaciones Biológicas, CSIC, Ramiro de Maeztu 9, E-28040 Madrid, Spain atmartinez@cib.csic.es.
authors: Angel T
authors: AT
authors: Martínez
mesh_terms: D002794:Choline / Q000378:metabolism*; D005656:Fungal Proteins / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D016681:Genome, Fungal; D005947:Glucose / Q000378:metabolism*; D006861:Hydrogen Peroxide / Q000378:metabolism*; D000432:Methanol / Q000378:metabolism*; D008958:Models, Molecular; D010088:Oxidoreductases / Q000737:chemistry / Q000235:genetics* / Q000378:metabolism; D010802:Phylogeny; D020072:Polyporales / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism
chemical_list: D005656:Fungal Proteins; D006861:Hydrogen Peroxide; D010088:Oxidoreductases; D005947:Glucose; D002794:Choline; D000432:Methanol
keywords: GMC oxidoreductases; brown-rot fungi; evolutionary relationships; sequenced genome analysis; white-rot fungi