Multicopy Chromosomal Integration Using CRISPR-Associated Transposases.
ACS Synth Biol
; 9(8): 1998-2008, 2020 08 21.
Article
em En
| MEDLINE
| ID: mdl-32551502
ABSTRACT
Controlling the copy number of gene expression cassettes is an important strategy to engineer bacterial cells into high-efficiency biocatalysts. Current strategies mostly use plasmid vectors, but multicopy plasmids are often genetically unstable, and their copy numbers cannot be precisely controlled. The integration of expression cassettes into a bacterial chromosome has advantages, but iterative integration is laborious, and it is challenging to obtain a library with varied gene doses for phenotype characterization. Here, we demonstrated that multicopy chromosomal integration using CRISPR-associated transposases (MUCICAT) can be achieved by designing a crRNA to target multicopy loci or a crRNA array to target multiple loci in the Escherichia coli genome. Within 5 days without selection pressure, E. coli strains carrying cargos with successively increasing copy numbers (up to 10) were obtained. Recombinant MUCICAT E. coli containing genomic multicopy glucose dehydrogenase expression cassettes showed 2.6-fold increased expression of this important industrial enzyme compared to E. coli harboring the conventional protein-expressing plasmid pET24a. Successful extension of MUCICAT to Tatumella citrea further demonstrated that MUCICAT may be generally applied to many bacterial species.
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Texto completo:
1
Base de dados:
MEDLINE
Assunto principal:
Cromossomos Bacterianos
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Transposases
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Escherichia coli
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Repetições Palindrômicas Curtas Agrupadas e Regularmente Espaçadas
Tipo de estudo:
Risk_factors_studies
Idioma:
En
Ano de publicação:
2020
Tipo de documento:
Article