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Safety Training in our team
[NO CONTENT?!!!!!]
Kill Switch in E.coli
This year our safety work is based on E.coli, since some of our work is on light sensing and imaging system in E.coli. To make a wider application in the future, the biosafety of E.coli containing these parts should be concerned.
Anti-LPS factor(LALF) regulated by lacI
We designed the part based on K541545. We found that R0010 might keep expressing genes below without regulation.Reason may be that Lacl expressed by E.coil is limited. So we inserted parts that express Lacl and constitutive promoter before the old one to inhibit pLac. [Fig]
Anti-LPS factor(LALF) regulated by IPTG
This part is a cell-kill system. Firstly,constitutive promoter could express enough Lacl that is useful for downstream. Secondly, the reporter in the middle of our part wouldn't show signal nor the cell be killed by the part behind unless IPTG or lactose added into the culture medium. No IPTG or lactose: LALF won't express ,G- won't be killed. IPTG or lactose existing: LALF will express ,G- will be dead.
G-: Gram negative bacteria
Fig[]
Principle:
Limulus anti-LPS factor (LALF) binds LPS on anti-gram negative bacterial surface tightly, forming a biofilm. This can prevent nutrient from entering the cell, causing the growth inhibition.
Also, the biofilm can prevent Plasmid spreading to the environment and gene pollution.
Besides, to make LALF across the cell membrane and bind to LPS, we still need an efficient protein export signal sequence of E. coli. leading LALF into extra-cellular environment.
