title: The macromolecule with antimicrobial activity synthesized by Pseudoalteromonas luteoviolacea strains is an L-amino acid oxidase.
abstract: Two purple pigmented bacterial strains, CPMOR-1 and CPMOR-2, have been newly isolated from the Mediterranean Sea. 16S RNA sequencing and phenotypic characteristics indicate that they belong to the species Pseudoalteromonas luteoviolacea. The synthesis of macromolecules with antimicrobial activity is a capacity described in many strains of this species although the nature of those macromolecules has not been reported up to now. The search for antimicrobial compounds in the two new strains described in this work shows that they synthesize a macromolecule with antimicrobial activity that can be inhibited by catalase, as it had been described in the type strain P. luteoviolacea NCIMB 1893(T). This work elucidates the nature of such macromolecule as a novel L-amino acid oxidase (LAO) with broad substrate specificity. The enzyme is most active with Met, Gln, Leu, Phe, Glu, and Trp. In growth media containing those amino acids, the hydrogen peroxide generated by the reaction catalyzed by the LAO mediates its antimicrobial activity.
authors.affiliation: Department of Genetics and Microbiology, Faculty of Biology, University of Murcia, Murcia 30100, Spain.
authors.forename: Daniel
authors.initials: D
authors.lastname: Gómez
authors.forename: Elena
authors.initials: E
authors.lastname: Espinosa
authors.forename: Marcelo
authors.initials: M
authors.lastname: Bertazzo
authors.forename: Patricia
authors.initials: P
authors.lastname: Lucas-Elío
authors.forename: Francisco
authors.initials: F
authors.lastname: Solano
authors.forename: Antonio
authors.initials: A
authors.lastname: Sanchez-Amat
mesh_terms: D000596:Amino Acids / Q000378:metabolism; D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000378:metabolism* / Q000494:pharmacology; D001426:Bacterial Proteins / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D004269:DNA, Bacterial / Q000235:genetics; D004275:DNA, Ribosomal / Q000235:genetics; D004926:Escherichia coli / Q000187:drug effects; D050830:L-Amino Acid Oxidase / Q000737:chemistry / Q000235:genetics / Q000378:metabolism* / Q000494:pharmacology; D008969:Molecular Sequence Data; D031161:Pseudoalteromonas / Q000737:chemistry / Q000201:enzymology* / Q000235:genetics / Q000302:isolation & purification*; D012336:RNA, Ribosomal, 16S / Q000235:genetics; D012623:Seawater / Q000382:microbiology; D013379:Substrate Specificity
chemical_list: D000596:Amino Acids; D000900:Anti-Bacterial Agents; D001426:Bacterial Proteins; D004269:DNA, Bacterial; D004275:DNA, Ribosomal; D012336:RNA, Ribosomal, 16S; D050830:L-Amino Acid Oxidase