Difference between revisions of "Part:BBa K4621131"

Revision as of 18:25, 10 October 2023

Complex functional parts of SCUT-3-EctPi4 that induce high Hydroxyectoine production.

Usage, Biology and Characterization

LPMO hypothetical promoter is a whole functional sequence in front of the Lytic polysaccharide monooxygenase LPMO gene, which was cloned from SCUT-3 gene. In our project, through transcriptome analysis, qPCR and other means, we found that the gene expression of monooxygenase LPMO was up-regulated when SCUT-3 was in chitin medium, and we speculated that its promoter Pro lpmo may have properties that can be induced by chitin.

This CRISPRi fragment contains four parts : BBa _ K4621070, BBa _ K3875019, BBa _ K4621030, and BBa _ K3081104, covering the dCas9 and sgRNA necessary for the CRISPRi system. The CRISPRi system is suitable for a variety of Streptomyces.[1] In this study, it was used to inhibit the expression of GQS52 _ 08040 gene in SCUT-3 to produce more ectoine and hydroxyectoine.

Fig.1Mechanism of CRISPRi

Testing and validation

Due to the limited types of plasmids available for SCUT-3, we inserted the CRISPRi fragment into the previously constructed plasmid PZ-ProP-Ect-i4 by homologous recombination to achieve simultaneous stable expression of multiple target genes. Subsequently, we verified the effectiveness of the CRISPRi system in the fermentation of ordinary LB, high-salt LB and shrimp shells.

Fig.2 Fermentation under the high salt environment

Fig.3 Fermentation using shrimp shells

Reference

[1] Zhao Y, Li L, Zheng G, Jiang W, Deng Z, Wang Z, Lu Y. CRISPR/dCas9-Mediated Multiplex Gene Repression in Streptomyces. Biotechnol J. 2018 Sep;13(9):e1800121. doi: 10.1002/biot.201800121. Epub 2018 Jul 4. PMID: 29862648.

Sequence and Features