Development of Efficient Bacterial Hosts for Recombinant Membrane Protein Production

A majority of membrane proteins are very difficult to obtain in significant quantities, even at milligram scale, because their natural biosynthesis levels often are very low, and currently available protein expression systems are not effective for membrane proteins. With the completion of several genome sequencing projects, many large-scale efforts are under way to understand the protein products. However, the lack of effective methods for preparative-scale, membrane protein synthesis hampers progress toward a complete understanding of the proteome, and prevents taking full advantage of the available sequences ¿ especially those membrane proteins that constitute the majority of drug targets. The development of a system capable of synthesizing any desired protein on a preparative scale is one of the most important endeavors in biotechnology today. Although many in vivo protein expression systems are very powerful, capable of producing gram quantities of soluble proteins, their applications to membrane protein synthesis have yielded poor results. This project will develop an expression system that will provide recombinant membrane proteins at quantities comparable to soluble protein expression systems. The approach involves using genetically engineered expression strains with various membrane protein expression vectors that already have been constructed. The expression system will be designed for convenient use, large-scale protein synthesis, and high throughput. Commercial Applications and other Benefits as described by the awardee: The system should find use in the large-scale production of medicinally important membrane proteins that are very difficult to prepare. The recombinant membrane proteins would find use in high throughput screening, in the structural biology of membrane proteins crucial to structure-based drug design, and in the structural genomics of membrane proteins. Reagents associated with the system could be made available for research use.