Difference between revisions of "Part:BBa K3332069"
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'''Enzyme activity'''
 
'''Enzyme activity'''
  
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        We use Negative Control, experiment groups phnEE and Mut21_phnJ-phnEE to verify that Mut21_phnJ can enhance the degradation of glyphosate by the chassis bacteria by our detection system. The Mut21_phnJ-phnEE gene cluster enhances the degration of glyphosate by the chassis bacteria compared to the blank control, but it has no difference with the phnE1E2 group, indicating that exogenous phnJ can’t bind to the endogenous PhnHIK well.  
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        We use Negative Control, experiment groups phnEE and Mut21_phnJ-phnEE to analyze if Mut21_phnJ enhances the degradation of glyphosate by the chassis bacteria by our detection system. Mut21_phnJ gene lowers the degradation rate of ''E.coli'' BL21(DE3) about 16.4%, indicate the mutant has higher binding ability to PhnHIK but lower degradation ability compare to endogenous PhnJ.  
  
 
        The result is shown in Fig.2(Experiment groups in Fig.2  
 
        The result is shown in Fig.2(Experiment groups in Fig.2  

Revision as of 22:21, 27 October 2020


J23100-RBS-phnJ_mut21-terminator

Use BBa_K823004-BBa_B0034 to express the mutant of C-P lyase, which can degrade the glyphosate, from Enterobacterales. This subunit is essential to the activity of the whole enzyme.Improve the capability of chassis bacteria to degrade glyphosate.

Biology

        Phn system is a gene cluster for organophosphorus transport and degradation in many microorganisms. Enterobacterales use phnHIJK genes to encode C-P lyase. PhnJ protein is an essential subunit that can crack C-P bond. The 21th arginine was mutated to methionine.

Usage

        We ligased the J23100-B0034-phnJ_mut21-B0015 (BBa_K3332025) and the part J23100-B0034-phnE1-B0034-phnE2(BBa_K3332067) on the expression vector pSB1C3 by standard assembly. Then the ligation mixture was transformed into E. coli DH5α & E. coli BL21(DE3), which enables the E. coli to degrade glyphosate at higher efficiency and improved the binding ability with the endogenous PhnHIK.

Characterization

Enzyme activity

        We use Negative Control, experiment groups phnEE and Mut21_phnJ-phnEE to analyze if Mut21_phnJ enhances the degradation of glyphosate by the chassis bacteria by our detection system. Mut21_phnJ gene lowers the degradation rate of E.coli BL21(DE3) about 16.4%, indicate the mutant has higher binding ability to PhnHIK but lower degradation ability compare to endogenous PhnJ.

        The result is shown in Fig.2(Experiment groups in Fig.2

       Negative Control: J23100-B0034_pSB1C3

       phnE1E2: J23100-B0034-phnE1-B0034-phnE2_pSB1C3,

       phnJ-phnE1E2: J23100-B0034-phnJ-B0015-J23100-B0034-phnE1-B0034-phnE2_pSB1C3,

       Mut21-phnJ-phnE1E2: J23100-B0034-phnJ_mutR21M-B0015- J23100-B0034-phnE1-B0034-phnE2_pSB1C3

       Mut1640-phnJ-phnE1E2: J23100-B0034-phnJ_mutT16S&R40Y-B0015-J23100-B0034-phnE1-B0034-phnE2_pSB1C3

       RNAi system-phnJ-phnO-phnE1E2: J23101-OmpA 5'UTR-phnF 0.97-Hfq binding sequence-J23101- OmpA 5'UTR-phnJ 0.69-Hfq binding sequence- BBa_J61048-J23100-B0034-phnJ-B0015-J23100-phnO-B0015-J23100-B0034-phnE1-B0034-phnE2_pSB1C3).

Fig.2 Relationship between concentration of glyphosate and culture time.