title: Novel hydrolase diversity retrieved from a metagenome library of bovine rumen microflora.
abstract: A metagenome expression library of bulk DNA extracted from the rumen content of a dairy cow was established in a phage lambda vector and activity-based screening employed to explore the functional diversity of the microbial flora. Twenty-two clones specifying distinct hydrolytic activities (12 esterases, nine endo-beta-1,4-glucanases and one cyclodextrinase) were identified in the library and characterized. Sequence analysis of the retrieved enzymes revealed that eight (36%) were entirely new and formed deep-branched phylogenetic lineages with no close relatives among known ester- and glycosyl-hydrolases. Bioinformatic analyses of the hydrolase gene sequences, and the sequences and contexts of neighbouring genes, suggested tentative phylogenetic assignments of the rumen organisms producing the retrieved enzymes. The phylogenetic novelty of the hydrolases suggests that some of them may have potential for new applications in biocatalysis.
authors.affiliation: Department of Microbiology, GBF- German Research Centre for Biotechnology, Mascheroder Weg 1, 38124 Braunschweig, Germany. m.ferrer@icp.csic.es
authors.forename: Manuel
authors.initials: M
authors.lastname: Ferrer
authors.forename: Olga V
authors.initials: OV
authors.lastname: Golyshina
authors.forename: Tatyana N
authors.initials: TN
authors.lastname: Chernikova
authors.forename: Amit N
authors.initials: AN
authors.lastname: Khachane
authors.forename: Dolores
authors.initials: D
authors.lastname: Reyes-Duarte
authors.forename: Vitor A P Martins Dos
authors.initials: VA
authors.lastname: Santos
authors.forename: Carsten
authors.initials: C
authors.lastname: Strompl
authors.forename: Kieran
authors.initials: K
authors.lastname: Elborough
authors.forename: Graeme
authors.initials: G
authors.lastname: Jarvis
authors.forename: Alexander
authors.initials: A
authors.lastname: Neef
authors.forename: Michail M
authors.initials: MM
authors.lastname: Yakimov
authors.forename: Kenneth N
authors.initials: KN
authors.lastname: Timmis
authors.forename: Peter N
authors.initials: PN
authors.lastname: Golyshin
mesh_terms: D000818:Animals; D001426:Bacterial Proteins / Q000235:genetics*; D044822:Biodiversity; D002417:Cattle; D005260:Female; D005656:Fungal Proteins / Q000235:genetics*; D005798:Genes, Bacterial; D005800:Genes, Fungal; D017238:Genes, Helminth; D015801:Helminth Proteins / Q000235:genetics; D006867:Hydrolases / Q000235:genetics*; D008969:Molecular Sequence Data; D009520:New Zealand; D012417:Rumen / Q000382:microbiology* / Q000469:parasitology
chemical_list: D001426:Bacterial Proteins; D005656:Fungal Proteins; D015801:Helminth Proteins; D006867:Hydrolases