Difference between revisions of "Part:BBa K4621151"

Revision as of 17:45, 5 October 2023

It consists of the chi18B hypothetical promoter and EctOperon.

Usage, Biology and Characterization

EctOperon contains ectA, ectB, ectC and ectD and can produce 5-Hydroxyectoine from lysine.

chi18B hypothetical promoter is a functional fragment in chitinase Chi18B 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 chitinase Chi18B was up-regulated when SCUT-3 was in chitin medium, and we speculated that its promoter chi18B hypothetical promoter may have properties that can be induced by chitin.

Testing and validation

We ligated the chi18B hypothetical promoter with EctOperon and overexpressed it in Streptomyces SCUT-3 using an integrated plasmid. The modified strain was inoculated in 40 mL LB medium and fermented at 40℃ and 220 rpm for 120h. The production of Ectoine and 5-Hydroxyectoin in the presence or without chitin (the first day of fermentation) was detected to evaluate the chitin inducability of the promoter. The results are shown in FIG. 1.

Fig.1 Fermentation of products with or without the addition of an inducer（chitin) (a).Ectoine (b).5-Hydroxyectoin(72h)

Sequence and Features