Characterization and engineering of a carotenoid biosynthesis operon from Bacillus megaterium.
Metab Eng
; 49: 47-58, 2018 09.
Article
em En
| MEDLINE
| ID: mdl-30055324
ABSTRACT
Bacillus megaterium belongs to the group of pigmented bacilli producing carotenoids that ensure self-protection from UV radiation-induced and collateral oxidative damage. Metabolite profiling of strain MS941 revealed the presence of the C30 carotenoids 4,4'-diapophytofluene and 4,4'-diaponeurosporenic acid. A gene function analysis demonstrated the presence of a corresponding C30 carotenoid biosynthetic pathway with pharmaceutical importance. We identified a gene cluster comprising putative genes for a farnesyl diphosphate synthase (IspA), a diapophytoene synthase (CrtM) and three distinct diapophytoene desaturases (CrtN1-3). Intriguingly, crtM was organized in an operon together with two of the identified crtN genes. The individual activities of the encoded enzymes were determined by heterologous expression and product analysis in the non-carotenogenic model organism Escherichia coli. Our experimental data show that the first catalytic steps of C30 carotenoid biosynthesis in B. megaterium share significant similarity to the corresponding biosynthetic pathway of Staphylococcus aureus. The biosynthesis of farnesyl diphosphates and their subsequent condensation to form 4,4'-diapophytoene are catalyzed by the identified IspA and CrtM, respectively. The following desaturation reactions to form 4,4'-diaponeurosporene, however, require the activities of multiple diapophytoene desaturases. A biosynthetic operon was engineered and successfully expressed in an E. coli whole-cell system creating a cell factory for a high-yield production of the C30 carotenoid 4,4'-diaponeurosporene which has promising potential in the treatment of various inflammatory diseases.
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Texto completo:
1
Bases de dados:
MEDLINE
Assunto principal:
Óperon
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Bacillus megaterium
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Proteínas de Bactérias
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Carotenoides
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Escherichia coli
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Engenharia Metabólica
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Microrganismos Geneticamente Modificados
Tipo de estudo:
Prognostic_studies
Idioma:
En
Revista:
Metab Eng
Assunto da revista:
ENGENHARIA BIOMEDICA
/
METABOLISMO
Ano de publicação:
2018
Tipo de documento:
Article
País de afiliação:
Alemanha