title: Gulosibacter molinativorax ON4T molinate hydrolase, a novel cobalt-dependent amidohydrolase.
abstract: A new pathway of molinate mineralization has recently been described. Among the five members of the mixed culture able to promote such a process, Gulosibacter molinativorax ON4(T) has been observed to promote the initial breakdown of the herbicide into ethanethiol and azepane-1-carboxylate. In the current study, the gene encoding the enzyme responsible for molinate hydrolysis was identified and heterologously expressed, and the resultant active protein was purified and characterized. Nucleotide sequence analysis revealed that the gene encodes a 465-amino-acid protein of the metal-dependent hydrolase A subfamily of the amidohydrolase superfamily with a predicted molecular mass of 50.9 kDa. Molinate hydrolase shares the highest amino acid sequence identity (48 to 50%) with phenylurea hydrolases of Arthrobacter globiformis and Mycobacterium brisbanense. However, in contrast to previously described members of the metal-dependent hydrolase A subfamily, molinate hydrolase contains cobalt as the only active-site metal.
authors.affiliation: LEPAE-Departamento de Engenharia Química, Faculdade de Engenharia, Universidade do Porto, Porto, Portugal.
authors.forename: Márcia
authors.initials: M
authors.lastname: Duarte
authors.forename: Frederico
authors.initials: F
authors.lastname: Ferreira-da-Silva
authors.forename: Heinrich
authors.initials: H
authors.lastname: Lünsdorf
authors.forename: Howard
authors.initials: H
authors.lastname: Junca
authors.forename: Luís
authors.initials: L
authors.lastname: Gales
authors.forename: Dietmar H
authors.initials: DH
authors.lastname: Pieper
authors.forename: Olga C
authors.initials: OC
authors.lastname: Nunes
mesh_terms: D000192:Actinomycetales / Q000145:classification / Q000201:enzymology* / Q000235:genetics / Q000378:metabolism; D000581:Amidohydrolases / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D000595:Amino Acid Sequence; D001381:Azepines / Q000378:metabolism*; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism*; D020134:Catalytic Domain; D003035:Cobalt / Q000378:metabolism*; D006540:Herbicides / Q000378:metabolism*; D008969:Molecular Sequence Data; D010802:Phylogeny; D016415:Sequence Alignment; D013859:Thiocarbamates / Q000378:metabolism*
chemical_list: D001381:Azepines; D001426:Bacterial Proteins; D006540:Herbicides; D013859:Thiocarbamates; D003035:Cobalt; C009821:molinate; D000581:Amidohydrolases