title: A nitrile hydratase in the eukaryote Monosiga brevicollis.
abstract: Bacterial nitrile hydratase (NHases) are important industrial catalysts and waste water remediation tools. In a global computational screening of conventional and metagenomic sequence data for NHases, we detected the two usually separated NHase subunits fused in one protein of the choanoflagellate Monosiga brevicollis, a recently sequenced unicellular model organism from the closest sister group of Metazoa. This is the first time that an NHase is found in eukaryotes and the first time it is observed as a fusion protein. The presence of an intron, subunit fusion and expressed sequence tags covering parts of the gene exclude contamination and suggest a functional gene. Phylogenetic analyses and genomic context imply a probable ancient horizontal gene transfer (HGT) from proteobacteria. The newly discovered NHase might open biotechnological routes due to its unconventional structure, its new type of host and its apparent integration into eukaryotic protein networks.
authors.affiliation: European Molecular Biology Laboratory, Heidelberg, Germany.
authors.forename: Konrad U
authors.initials: KU
authors.lastname: Foerstner
authors.forename: Tobias
authors.initials: T
authors.lastname: Doerks
authors.forename: Jean
authors.initials: J
authors.lastname: Muller
authors.forename: Jeroen
authors.initials: J
authors.lastname: Raes
authors.forename: Peer
authors.initials: P
authors.lastname: Bork
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D056890:Eukaryota / Q000201:enzymology* / Q000235:genetics; D005057:Eukaryotic Cells / Q000201:enzymology; D006836:Hydro-Lyases / Q000737:chemistry / Q000235:genetics / Q000302:isolation & purification* / Q000378:metabolism; D008954:Models, Biological; D010802:Phylogeny; D021122:Protein Subunits / Q000737:chemistry
chemical_list: D021122:Protein Subunits; D006836:Hydro-Lyases; C048831:nitrile hydratase