title: LodB is required for the recombinant synthesis of the quinoprotein L-lysine-ε-oxidase from Marinomonas mediterranea.
abstract: Marinomonas mediterranea is a marine gamma-proteobacterium that synthesizes LodA, a novel L-lysine-ε-oxidase (E.C. 1.4.3.20). This enzyme oxidizes L-lysine generating 2-aminoadipate 6-semialdehyde, ammonium, and hydrogen peroxide. Unlike other L-amino acid oxidases, LodA is not a flavoprotein but contains a quinone cofactor. LodA is encoded by an operon with two genes, lodA and lodB. In the native system, LodB is required for the synthesis of a functional LodA. In this study, we report the recombinant expression of LodA in Escherichia coli using vectors that allow its expression and accumulation in the cytoplasm. To reveal the L-lysine-ε-oxidase activity using the Amplex Red method for hydrogen peroxide detection, it is necessary to first remove the E. coli cytoplasmic catalases. The flavoprotein LodB is the only M. mediterranea protein required in the recombinant system for the generation of the cofactor of LodA. In the absence of LodB, LodA does not contain the quinone cofactor and remains in an inactive form. The results presented indicate that LodB participates in the posttranslational modification of LodA that generates the quinone cofactor.
authors: Department of Genetics and Microbiology, University of Murcia, Murcia, 30100, Spain.
authors: María Dolores
authors: MD
authors: Chacón-Verdú
authors: Daniel
authors: D
authors: Gómez
authors: Francisco
authors: F
authors: Solano
authors: Patricia
authors: P
authors: Lucas-Elío
authors: Antonio
authors: A
authors: Sánchez-Amat
mesh_terms: D000594:Amino Acid Oxidoreductases / Q000096:biosynthesis* / Q000235:genetics; D001426:Bacterial Proteins / Q000235:genetics / Q000378:metabolism*; D003067:Coenzymes / Q000378:metabolism; D004926:Escherichia coli / Q000235:genetics / Q000378:metabolism; D053544:Marinomonas / Q000201:enzymology* / Q000378:metabolism*; D011809:Quinones / Q000378:metabolism; D011994:Recombinant Proteins / Q000096:biosynthesis / Q000235:genetics
chemical_list: D001426:Bacterial Proteins; D003067:Coenzymes; D011809:Quinones; D011994:Recombinant Proteins; D000594:Amino Acid Oxidoreductases; C041123:L-lysine oxidase