It has been reported that chemically synthesized peptides produced by the Tang Yu research group of Lanzhou University could bind to heavy metals. These peptides possess affinity for binding heavy metals. Thus, we attempted to use bacteria to synthesize such peptides anchored on the cell membrane. Importantly, the surface display strategy for heavy metal adsorption has an advantage over traditional bio-adsorption methods due to the burden of intracellular accumulation of toxics metal ions. Herein, we present a series of parts that we constructed for our purpose.
We would like to point out several of our parts as they were crucial and fundamental for our work. Below this section, a list of all registered parts can be found.
BBa_K1995005: IC (INP-N-GFP-C) – Favorite Part
IC (Cys- lys- Cys- lys- Cys- lys- Cys), has a high affinity and selectivity toward mercury. The subsequent IC and GFP (Green Fluorescent Protein) were fused and displayed on Escherichia coli cell surface by using an N-terminal region ice nucleation protein anchor. Whole-cell sorbents of construction facilitated selective adsorption of mercury ions from a solution containing different heavy metal ions and detection for mercury and cooper. The transformant strains were then fed to Cyprinus carpio and colonized in the microbiota. C. carpio with transformants showed significantly lower accumulation of heavy metals compared to the control group.For more data and figure about IC pleaseClick Here
Figure 4: (A) Selectivity of the IC sensing system. (B) Fluorescence response of IC (OD600 = 1.3) in the presence of Cu2+ and various additional metal ions. The black bars represent the addition of an excess of the appropriate metal ion (50 µM) to a bacterial solution. The red bars represent the subsequent addition of 100 µM CuSO4 to the solution. Excitation wavelength: 488 nm.
Figure 5: (A) Fluorescence spectra of IC (OD600 = 1.3) in the presence of Cu2+ with varying concentrations. (B) Fluorescence responses of IC to Cu2+ with varying concentrations.
Figure 9: Reduced bioaccumulated heavy metals in Cyprinus carpio by gut remediation.
BBa_K1960450: CFP and lacI – A part we improved
LacI is the regulator gene of lac operon in E. coli, which will inhibit the lac operon when expressed. LacI can bind to lactose and it cannot inhibit lac operon under excess lactose, then the gene in lac operon like lacZ、lacY、lacA can be expressed.The expression level of lacI can be easily detected after connecting CFP with lacI. So we can figure out whether lacI is related to the expressing of other gene conveniently by this improved part.
|BBa_K1995024||IHG||INP-N (N-terminal of Ice Nucleation Protein) + GFP + HG (His-Pro-Gly-His-Trp-Gly)||More information|
|BBa_K1995002||PHG||INP-N (N-terminal of Ice Nucleation Protein) + HG (His-Pro-Gly-His-Trp-Gly)||More information|
|BBa_K1995003||HG||GFP + HG (His-Pro-Gly-His-Trp-Gly)||More information|
|BBa_K1995005||IC||INP-N (N-terminal of Ice Nucleation Protein) + GFP + C ((Cys-Lys-Cys)2)||More information|
|BBa_K1995006||2C||GFP + C((Cys-Lys-Cys)2)||More information|
|BBa_K1995007||PC||INP-N (N-terminal of Ice Nucleation Protein) + C ((Cys-Lys-Cys)2)||More information|
|BBa_K1995009||2H||GFP + H ((His-Lys-His)2)||More information|
|BBa_K19950010||PH||INP-N (N-terminal of Ice Nucleation Protein) + H ((His-Lys-His)2)||More information|
|BBa_K19950011||IH||INP-N (N-terminal of Ice Nucleation Protein) + GFP + H ((His-Lys-His)2)||More information|
|BBa_K19950013||GA||GFP + merA (Mercuric reductase)||More information|
|BBa_K19950014||IA||INP-N (N-terminal of Ice Nucleation Protein) + merA (Mercuric reductase)||More information|
|BBa_K19950016||IR||INP-N (N-terminal of Ice Nucleation Protein) + merR (Mercuric resistance operon regulatory protein)||More information|
|BBa_K19950017||RG||merR (Mercuric resistance operon regulatory protein) + GFP||More information|
|BBa_K19950019||CC||INP-N (N-terminal of Ice Nucleation Protein) + GFP + CC (C-K-C-K-C-K-C-K-C-K-C)||More information|
|BBa_K19950020||CCW||GFP + CC (C-K-C-K-C-K-C-K-C-K-C) + secretion expression vector||More information|