title: Applying functional metagenomics to search for novel lignocellulosic enzymes in a microbial consortium derived from a thermophilic composting phase of sugarcane bagasse and cow manure.
abstract: Environments where lignocellulosic biomass is naturally decomposed are sources for discovery of new hydrolytic enzymes that can reduce the high cost of enzymatic cocktails for second-generation ethanol production. Metagenomic analysis was applied to discover genes coding carbohydrate-depleting enzymes from a microbial laboratory subculture using a mix of sugarcane bagasse and cow manure in the thermophilic composting phase. From a fosmid library, 182 clones had the ability to hydrolyse carbohydrate. Sequencing of 30 fosmids resulted in 12 contigs encoding 34 putative carbohydrate-active enzymes belonging to 17 glycosyl hydrolase (GH) families. One third of the putative proteins belong to the GH3 family, which includes β-glucosidase enzymes known to be important in the cellulose-deconstruction process but present with low activity in commercial enzyme preparations. Phylogenetic analysis of the amino acid sequences of seven selected proteins, including three β-glucosidases, showed low relatedness with protein sequences deposited in databases. These findings highlight microbial consortia obtained from a mixture of decomposing biomass residues, such as sugar cane bagasse and cow manure, as a rich resource of novel enzymes potentially useful in biotechnology for saccharification of lignocellulosic substrate.
authors.affiliation: Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Lívia Tavares
authors.initials: LT
authors.lastname: Colombo
authors.affiliation: Department of Basic Life Sciences, Universidade Federal de Juiz de Fora, Governador Valadares, MG, 35020-220, Brazil.
authors.forename: Marcelo Nagem Valério
authors.initials: MN
authors.lastname: de Oliveira
authors.affiliation: Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Deisy Guimarães
authors.initials: DG
authors.lastname: Carneiro
authors.affiliation: Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Robson Assis
authors.initials: RA
authors.lastname: de Souza
authors.affiliation: Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Mariana Caroline Tocantins
authors.initials: MC
authors.lastname: Alvim
authors.affiliation: Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Josenilda Carlos
authors.initials: JC
authors.lastname: Dos Santos
authors.affiliation: Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Cynthia Canêdo
authors.initials: CC
authors.lastname: da Silva
authors.affiliation: Biomolecules Analysis Center, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Pedro Marcus Pereira
authors.initials: PM
authors.lastname: Vidigal
authors.affiliation: Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil.
authors.forename: Wendel Batista
authors.initials: WB
authors.lastname: da Silveira
authors.affiliation: Department of Microbiology, Universidade Federal de Viçosa, Viçosa, MG, 36570-000, Brazil. flpassos@ufv.br.
authors.forename: Flávia Maria Lopes
authors.initials: FM
authors.lastname: Passos
mesh_terms: D000818:Animals; D001419:Bacteria / Q000201:enzymology / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism; D018533:Biomass; D002417:Cattle; D044602:Cellulases / Q000235:genetics / Q000378:metabolism*; D002482:Cellulose / Q000378:metabolism*; D004789:Enzyme Activation; D000431:Ethanol / Q000378:metabolism; D008031:Lignin / Q000378:metabolism*; D008372:Manure / Q000382:microbiology*; D056186:Metagenomics; D059013:Microbial Consortia / Q000235:genetics*; D010802:Phylogeny; D031786:Saccharum / Q000378:metabolism / Q000382:microbiology*; D017422:Sequence Analysis, DNA; D001617:beta-Glucosidase / Q000235:genetics / Q000378:metabolism
chemical_list: D001426:Bacterial Proteins; D008372:Manure; C036909:lignocellulose; D000431:Ethanol; D002482:Cellulose; D008031:Lignin; C027433:bagasse; D044602:Cellulases; D001617:beta-Glucosidase
keywords: Cellulases genes; Cellulose degradation; Fosmid library sequencing; Metagenomic library