A Membrane‐Associated Light‐Harvesting Model is Enabled by Functionalized Assemblies of Gene‐Doubled TMV Proteins

Abstract

Photosynthetic light harvesting requires efficient energy transfer within dynamic networks of light‐harvesting complexes embedded within phospholipid membranes. Artificial light‐harvesting models are valuable tools for understanding the structural features underpinning energy absorption and transfer within chromophore arrays. Here, a method for attaching a protein‐based light‐harvesting model to a planar, fluid supported lipid bilayer (SLB) is developed. The protein model consists of the tobacco mosaic viral capsid proteins that are gene‐doubled to create a tandem dimer (dTMV). Assemblies of dTMV break the facial symmetry of the double disk to allow for differentiation between the disk faces. A single reactive lysine residue is incorporated into the dTMV assemblies for the site‐selective attachment of chromophores for light absorption. On the opposing dTMV face, a cysteine residue is incorporated for the bioconjugation of a peptide containing a polyhistidine tag for association with SLBs. The dual‐modified dTMV complexes show significant association with SLBs and exhibit mobility on the bilayer. The techniques used herein offer a new method for protein‐surface attachment and provide a platform for evaluating excited state energy transfer events in a dynamic, fully synthetic artificial light‐harvesting system.

Protein-Based Model for Energy Transfer between Photosynthetic Light-Harvesting Complexes Is Constructed Using a Direct Protein–Protein Conjugation Strategy

“…In a recent report, we have demonstrated the ability to incorporate the TMV-based light-harvesting model into a supported lipid bilayer. 49 We have also recently used the TMV model to identify sources of disorder in biomimetic lightharvesting systems and their effect on long-range energy transfer. 29 The ability to couple two TMV assemblies asymmetrically adds another layer of utility to the TMV-based model system by allowing energy transfer between donor and acceptor complexes at controlled distances and orientations to be examined.…”

“…In a recent report, we have demonstrated the ability to incorporate the TMV-based light-harvesting model into a supported lipid bilayer . We have also recently used the TMV model to identify sources of disorder in biomimetic light-harvesting systems and their effect on long-range energy transfer .…”

Highly Efficient Photoelectrochemical Detection of Cystatin C Based on a Core–Shell MOF Nanocomposite with Biomimetic-Catalysis Amplification

“…H 2 O 2 , as the electron donor, played the role of electron transfer in the detection system. To confirm the best concentration of H 2 O 2 electrolyte solution, different concentrations of H 2 O 2 (4,8,12,16, and 20 mM) were prepared. As is shown in Figure S3C, the photocurrent reached the maximum at 12 mM; then, the photocurrent trend flattened out, which might be due to saturation of electron transfer.…”

“…Simultaneously, in this work, the l -cysteine ( l -Cys) bilayer/ l -Cys-hemin/G-quadruplex was applied for the first time in a PEC sensor as a self-catalytic enzyme with efficient autocatalysis. The traditional strategy of hemin/G-quadruplex achieves signal amplification by converting Fe­(III)/Fe­(II) of hemin in the H 2 O 2 solution; hemin/G-quadruplex can accept electrons from photosensitive materials to reduce the recombination rate of electron–hole pairs . However, the above strategy has fatal drawbacks.…”

“…The traditional strategy of hemin/G-quadruplex achieves signal amplification by converting Fe(III)/Fe(II) of hemin in the H 2 O 2 solution; hemin/G-quadruplex can accept electrons from photosensitive materials to reduce the recombination rate of electron–hole pairs. 16 However, the above strategy has fatal drawbacks. H 2 O 2 will suffer instability and decomposition when the traditional hemin/G-quadruplex reacts.…”