title: Nitrile hydrolysing activities of deep-sea and terrestrial mycolate actinomycetes.
abstract: Nitrile metabolising actinomycetes previously recovered from deep-sea sediments and terrestrial soils were investigated for their nitrile transforming properties. Metabolic profiling and activity assays confirmed that all strains catalysed the hydrolysis of nitriles by a nitrile hydratase/amidase system. Acetonitrile and benzonitrile, when used as growth substrates for enzyme induction experiments, had a significant influence on the biotransformation activities towards various nitriles and amides. The specific activities of selected deep-sea and terrestrial acetonitrile-grown bacteria against a suite of nitriles and amides were higher than those of the only other reported marine nitrile-hydrolysing R. erythropolis, isolated from a shallow sediment. The increase of nitrile chain length appeared to have negative influence on the nitrile hydratase activity of acetonitrile-grown bacteria, but the same was not true for benzonitrile-grown bacteria. The nitrile hydratases and amidases were constitutive in 10 of the 16 deep-sea and terrestrial actinomycetes studied, and one strain showed an inducible hydratase and a constitutive amidase. Most of the deep-sea strains had constitutive activities and showed some of the highest activities and broadest substrate specificities of organisms included in this study.
authors.affiliation: Research School of Biosciences, University of Kent, Canterbury, Kent CT2 7NJ, UK.
authors.forename: Pedro F B
authors.initials: PF
authors.lastname: Brandão
authors.forename: Alan T
authors.initials: AT
authors.lastname: Bull
mesh_terms: D000081:Acetamides / Q000378:metabolism; D000097:Acetonitriles / Q000378:metabolism; D039903:Actinobacteria / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism*; D000581:Amidohydrolases / Q000378:metabolism; D001711:Biotransformation; D019015:Geologic Sediments / Q000382:microbiology; D006836:Hydro-Lyases / Q000378:metabolism; D006868:Hydrolysis; D007700:Kinetics; D009570:Nitriles / Q000378:metabolism*; D012240:Rhodococcus / Q000254:growth & development / Q000302:isolation & purification / Q000378:metabolism; D012623:Seawater / Q000382:microbiology; D012988:Soil Microbiology; D013379:Substrate Specificity
chemical_list: D000081:Acetamides; D000097:Acetonitriles; D009570:Nitriles; C030686:acetamide; D000581:Amidohydrolases; D006836:Hydro-Lyases; C048831:nitrile hydratase; C032159:acetonitrile