Identification and characterization of a novel plasmid-encoded laccase-like multicopper oxidase from Ochrobactrum sp. BF15 isolated from an on-farm bio-purification system

Research background. In recent decades, laccases (p-diphenol-dioxygen oxidoreductases; EC 1.10.3.2) have attracted the attention of researchers due to their wide range of biotechnological and industrial applications. Laccases can oxidize a variety of organic and inorganic compounds, making them suit...

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Detalles Bibliográficos
Autores: Martini, María Carla, Berini, Francesca, Ausec, Luka, Casciello, Carmine, Vacca, Carolina, Pistorio, Mariano, Lagares, Antonio, Mandic Mulec, Ines, Marinelli, Flavia, del Papa, Maria Florencia
Tipo de recurso: artículo
Estado:Versión publicada
Fecha de publicación:2021
País:Argentina
Institución:Consejo Nacional de Investigaciones Científicas y Técnicas
Repositorio:CONICET Digital (CONICET)
Idioma:inglés
OAI Identifier:oai:ri.conicet.gov.ar:11336/181562
Acceso en línea:http://hdl.handle.net/11336/181562
Access Level:acceso abierto
Palabra clave:BIODEGRADATION
BIOPURIFICATION SYSTEM
HETEROLOGOUS EXPRESSION
LACCASE-LIKE MULTICOPPER OXIDASES
OCHROBACTRUM
PLASMID
https://purl.org/becyt/ford/1.6
https://purl.org/becyt/ford/1
Descripción
Sumario:Research background. In recent decades, laccases (p-diphenol-dioxygen oxidoreductases; EC 1.10.3.2) have attracted the attention of researchers due to their wide range of biotechnological and industrial applications. Laccases can oxidize a variety of organic and inorganic compounds, making them suitable as biocatalysts in biotechnological processes. Even though the most traditionally used laccases in the industry are of fungal origin, bacterial laccases have shown an enormous potential given their ability to act on several substrates and in multiple conditions. The present study aims to characterize a plasmid-encoded laccase-like multicopper oxidase (LMCO) from Ochrobactrum sp. BF15, a bacterial strain previously isolated from polluted soil. Experimental approach. We used in silico profile hidden Markov models to identify novel laccase-like genes in Ochrobactrum sp. BF15. For laccase characterization, we performed heterologous expression in Escherichia coli, purification and activity measurement on typical laccase substrates. Results and conclusions. Profile hidden Markov models allowed us to identify a novel LMCO, named Lac80. In silico analysis of Lac80 revealed the presence of three conserved copper oxidase domains characteristic of three-domain laccases. We successfully expressed Lac80 heterologously in E. coli, allowing us to purify the protein for further activity evaluation. Of thirteen typical laccase substrates tested, Lac80 showed lower activity on 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid) (ABTS), pyrocatechol, pyrogallol and vanillic acid, and higher activity on 2,6-dimethoxyphenol. Novelty and scientific contribution. Our results show Lac80 as a promising laccase for use in industrial applications. The present work shows the relevance of bacterial laccases and highlights the importance of environmental plasmids as valuable sources of new genes encoding enzymes with potential use in biotechnological processes.