Functional characterization of a novel violacein biosynthesis operon from Janthinobacterium sp. B9-8.
Appl Microbiol Biotechnol
; 106(8): 2903-2916, 2022 Apr.
Article
em En
| MEDLINE
| ID: mdl-35445857
ABSTRACT
Violacein is a secondary metabolite mainly produced by Gram-negative bacteria that is formed from tryptophan by five enzymes encoded by a single operon. It is a broad-spectrum antibacterial pigment with various important biological activities such as anti-tumor, antiviral, and antioxidative effects. The newly discovered violacein operon vioABCDE was identified in the genome of the extremophile Janthinobacterium sp. B9-8. The key enzyme-encoding genes were cloned to construct the multigene coexpression plasmids pET-vioAB and pRSF-vioCDE. The violacein biosynthesis pathway was heterologously introduced into engineered Escherichia coli VioABCDE and VioABCDE-SD. The factors affecting violacein production, including temperature, pH, inoculum size, carbon and nitrogen source, precursor, and inducers were investigated. The violacein titer of VioABCDE-SD reached 107 mg/L in a two-stage fermentation process, representing a 454.4% increase over the original strain. The violacein operon from B9-8 provides a new microbial gene source for the analysis of the violacein synthesis mechanism, and the constructed engineering E. coli strains lay a foundation for the efficient and rapid synthesis of other natural products.Key points⢠The newly discovered violacein operon vioABCDE was identified in the genome of the extremophile Janthinobacterium sp. B9-8.⢠The violacein synthesis pathway was reconstructed in E. coli using two compatible plasmids.⢠A two-stage fermentation process was optimized for improved violacein accumulation.
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Texto completo:
1
Coleções:
01-internacional
Base de dados:
MEDLINE
Assunto principal:
Oxalobacteraceae
/
Escherichia coli
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Appl Microbiol Biotechnol
Ano de publicação:
2022
Tipo de documento:
Article
País de afiliação:
China