Biomimetic Membranes for Multi-Redox Center Proteins

Area of Science:

• Biophysics
• Biosensor Technology
• Protein Engineering

Background:

• His-tag technology facilitates controlled protein immobilization.
• Multi-redox center proteins (MRPs) are crucial for electron and proton transfer.
• Protein-tethered bilayer lipid membranes (ptBLMs) offer a platform for studying membrane proteins.

Purpose of the Study:

• To apply His-tag technology for orienting MRPs on various surfaces.
• To construct and investigate protein-tethered bilayer lipid membranes (ptBLMs) and proteo-lipobeads (PLBs).
• To demonstrate the functionality of immobilized MRPs for biosensing.

Main Methods:

• Utilized His-tag/NTA chemistry for oriented protein binding.
• Formed ptBLMs via in situ dialysis with lipid micelles.
• Employed electrochemical and surface-sensitive optical techniques (SPR, SEIRAS, SERRS) on flat surfaces.
• Investigated proteo-lipobeads (PLBs) using microscopy (LSM) and spectroscopy (UV/Vis).

Main Results:

• Successfully immobilized MRPs, including cytochrome c oxidase and photosynthetic reaction centers, in a defined orientation.
• Demonstrated electron and proton transfer through the immobilized MRPs within ptBLMs.
• Showed that membrane potential significantly affects protein function.
• Validated PLBs as a platform for studying protein function.

Conclusions:

• His-tag mediated ptBLM formation is effective for studying MRPs.
• MRPs within ptBLMs function under quasi-physiological conditions, suitable for biosensing.
• The developed methods allow for detailed investigation of electron and proton transfer processes in membrane proteins.