Engineering Bacteria to Control Electron Transport Altering the Synthesis of Non-native Biopolymer

Question

1. What is the role of C-Cyt in the synthesis of polymers?

2. What is the role of tPMETs in the synthesis of synthetic monomers?

3. What was the first derivative function applied to the voltammograms?

4. What is the role of cytochromes in bacterial EET?

Accepted Answer

Metal ion reduction takes place viamicrobial external electron transfer (EET) involving membrane bound C typeCytochrome (C-Cyt) proteins, possibly in combination with synergistic

Accepted Answer

1 Transplasma membrane electron transport systems [tPMETs] are essential from a biological energetic perspective and for mediation of cell redox and signaling.2, 3 It has recently been shown that electron transfer via tPMETs can be used to synthesise biopolymers (defined aspolymers syntesised by cells) and may have a role in radical polymerisations of synthetic monomers.

Accepted Answer

LSV was used to analyse the supernatant of incubated samples (N=2, n=6) and the firstderivative function was applied to resulting voltammograms.

Accepted Answer

C-Cyt was chosen as a target to mediate cell instructedATRP as cytochromes are known to play a substantial role in bacterial EET thatis required for energy production, particularly involving the reduction of metal ions.

Accepted Answer

NapC expression in bacteria containing pBADNAP (E.coli(BADNAP)) was induced by the addition of arabinose, which binds to AraC, activating the PBAD promoter and initiates transcription of the protein.

Accepted Answer

On the modification of NapC levels, there appear to be alterations inextracellular electron transfer which coincides with variations in differences in polymerisation kinetics.

Accepted Answer

An iron catalysed ATRP of the water-soluble monomer poly(ethylene glycol) methyl ether methacrylate (PEGMA, Mn = 300 gmol@1) was carried out at 37°C with tris(2-dimethylaminoethyl)amine (Me6TREN) for Fe3+ reduction.

Accepted Answer

School of Bioscience, Universityof Nottingham, Sutton Bonington Campus, Nottingham LE15 5RD[d] Division of Molecular Therapeutics and Formulation, Boots Science Building, Schoolof Pharmacy, University of Nottingham, University Park, Nottingham, NG7 2RDThe use of bacteria as catalysts for radical polymerisations of syntheticmonomers has recently been established.

Accepted Answer

PBAD would also allow us to control any potential toxicity and NapC expression by optimising the concentration ofinducer (arabinose).

Accepted Answer

(a) First derivative function applied to Linear sweepvoltammogram of ferricyanide/ferrocyanide redox couple (Fig S6) to determine d(Iss)/dt values.

Accepted Answer

These might include electron transfer (ET) across the periplasm via other cascade proteins in the electron transport chain, or EET between shuttle molecules and the Fe catalyst (Figure 2b).

Accepted Answer

This is of note because higher ferricyanide reduction was expected from E. coli clones thatwere induced with arabinose as indicated by the western blot which indicated increased NapC expression when compared to the cells modified with the control plasmid (Figure S3).

Accepted Answer

To study the resulting change in EET the authors used an electrochemical method that the authors have recently reported.2, 27 Herein the authors find that overexpression of theNapC protein in E. coli alters EET and this changes the kinetics of the reported cellinstructed bio-mediated polymerisations.

Accepted Answer

all cell polymerisation studies were performed when cells had reached an OD of 500 and therefore observed effects were not due to differing growth rates.

Accepted Answer

The authors attribute this to a shift in the bioenergetics ofthe bacteria, that could have been triggered in E. coli(IP_0.0018%) and E. coli(IP_0.18%) cultures, whereby EET reduction pathways were stunted due to the use ofexcess energy required for the over-production of the NapC protein.

Accepted Answer

V.; Boyer, H. W.; Yanofsky, C.; Lovett, M. A.; Helinski, D. R., Plasmid ColE1 as a molecular vehicle for cloning and amplification of DNA.

Engineering Bacteria to Control Electron Transport Altering the Synthesis of Non-native Biopolymer

Chat with Paper

AI Agents for this Paper

Most frequently asked questions

1. What is the role of C-Cyt in the synthesis of polymers?

2. What is the role of tPMETs in the synthesis of synthetic monomers?

3. What was the first derivative function applied to the voltammograms?

4. What is the role of cytochromes in bacterial EET?

5. What is the effect of arabinose on NapC expression in E. coli?

6. What is the effect of the PBAD promoter on the alterations in the Nap?

7. What is the effect of the iron catalysed ATRP on Fe3+?

8. What is the role of tPMET in the polymerisation of synthetic monomers?

9. What is the effect of PBAD on EET?

10. What is the function used to determine d(Iss)/dt?

11. What could be contributing to the EET from the bacteria to the Fe catalyst?

12. What is the effect of arabinose on the tPMET?

13. What is the kinetics of the EET change?

14. Why did all cell polymerisation studies occur when cells reached an OD of 500?

15. What is the reason why the EET reduction pathways were stunted?

16. what is the cloning of a plasmid?

Figures

Citations

Extracellular Electron Transfer Enables Cellular Control of Cu(I)-Catalyzed Alkyne–Azide Cycloaddition

Extracellular Electron Transfer Enables Cellular Control of Cu(I)-catalyzed Alkyne-Azide Cycloaddition

References

Plasmid ColE1 as a Molecular Vehicle for Cloning and Amplification of DNA

A modular system for Clostridium shuttle plasmids.

Recent Advances in the Theory and Molecular Simulation of Biological Electron Transfer Reactions.

Bioenergetic challenges of microbial iron metabolisms

Mechanisms of gold biomineralization in the bacterium Cupriavidus metallidurans

Related Papers (5)

Shewanella oneidensis as a living electrode for controlled radical polymerization.

Two Routes for Extracellular Electron Transfer in Enterococcus faecalis.

Geobacter cytochrome OmcZs binds riboflavin: implications for extracellular electron transfer

Bacterial Redox Potential Powers Controlled Radical Polymerization

Construction of an Electron Transfer Mediator Pathway for Bioelectrosynthesis by Escherichia coli.