Exclusive Interview with Prof. Dirk Linke on the Structural Biology of Membrane Proteins
CHI's Mary Ruberry recently spoke with Prof. Dirk Linke, a Professor of Genetics and Evolutionary Biology at the University of Oslo, regarding the structural biology of membrane proteins:
Structural Biology of Membrane Proteins: Expression Tricks, and to Solubilize or Not to Solubilize
Dirk Linke, PhD, Professor, Genetics and Evolutionary Biology, Biosciences, University of Oslo
In recent work, we have designed expression systems for bacterial outer membrane and surface proteins. These can be used to express and purify, e.g., important vaccine candidates for bacterial diseases, but also for studying membrane protein structure directly in the membrane with solid-state NMR methods.
Q: How do the expression systems function for studying membrane protein structure?
A: We work on membrane protein expression on different levels of the process. We have expression strains lacking major outer membrane proteins that leave more space in the membrane for heterologous proteins. In these same strains, the Sec machinery is less loaded with native proteins, giving us a higher export capacity. We also modify signal peptides and make fusion constructs for better export, folding, and detection.
Q: Are you studying membrane protein structures in situ?
A: We either purify them or study them in membranes - we can isolate membranes with simple centrifugation methods. Intact cells give too much background in our measurements, but with NMR technology advancing further, we might be able to overcome this.
Q: How are you employing solid-state NMR methods?
A: We use them on membrane preparations mostly, but also on purified proteins (sometimes even in crystallized form) or on artificial vesicles that include our target proteins.
Q: What are you most looking forward to at the PEGS Europe Summit?
A: I enjoy coming to the PEGS event to network with industry - and the feedback has always been amazing there.
Dr. Linke will be speaking about this topic in more detail on 16 November during Protein Purification Technologies at PEGS Europe:
Structural Biology of Membrane Proteins: Expression Tricks, and to Solubilize or Not to Solubilize
Dirk Linke, PhD, Professor, Genetics and Evolutionary Biology, Biosciences, University of Oslo
In recent work, we have designed expression systems for bacterial outer membrane and surface proteins. These can be used to express and purify, e.g., important vaccine candidates for bacterial diseases, but also for studying membrane protein structure directly in the membrane with solid-state NMR methods.
Dirk Linke graduated at the Technical University Berlin and was a PostDoc and Group Leader in the Max Planck Society in Tübingen, Germany before moving to Oslo, Norway where he now is a Full Professor in Molecular Microbiology.