Membranes and the proteins embedded within them compartmentalize specialized machinery that provides the means by which cells and organelles communicate, generate energy, take up nutrients, excrete wastes, transduce signals by transporting metabolites between internal compartments, and build gradients of ions (and other small molecules) which are used to fuel all normal cellular activities in healthy organisms. Structural information for membrane proteins is exceedingly scarce - it is notoriously difficult to purify quantities of native material that are sufficient for crystallization attempts. Today's methods for the overproduction of protein cannot deal with membrane proteins, thus this important class is virtually ignored. In order for significant advances to be made, innovative strategies are needed rather than incremental advances in existing technology. We have exploited the unique physiology of the Rhodobacter species of photosynthetic bacteria to overexpress heterologous proteins, and have recently shown that a human outer membrane protein is expressed and incorporated into induced membranes of this organism. We now propose to develop this system to be a general one for the expression of functional membrane proteins - from any organism - in quantities that are sufficient for biochemical studies and crystallization trials for structure determination.

Agency
National Institute of Health (NIH)
Institute
National Institute of General Medical Sciences (NIGMS)
Type
Research Project (R01)
Project #
5R01GM061887-05
Application #
6786562
Study Section
Special Emphasis Panel (ZRG1-SSS-A (01))
Program Officer
Edmonds, Charles G
Project Start
2000-08-01
Project End
2006-07-31
Budget Start
2004-08-01
Budget End
2006-07-31
Support Year
5
Fiscal Year
2004
Total Cost
$256,526
Indirect Cost
Name
University of Chicago
Department
Type
Organized Research Units
DUNS #
005421136
City
Chicago
State
IL
Country
United States
Zip Code
60637
Laible, Philip D; Hata, Aaron N; Crawford, Adam E et al. (2005) Incorporation of selenomethionine into induced intracytoplasmic membrane proteins of Rhodobacter species. J Struct Funct Genomics 6:95-102
Laible, Philip D; Scott, Heather N; Henry, Lynda et al. (2004) Towards higher-throughput membrane protein production for structural genomics initiatives. J Struct Funct Genomics 5:167-72
Pokkuluri, P Raj; Laible, Philip D; Crawford, Adam E et al. (2004) Temperature and cryoprotectant influence secondary quinone binding position in bacterial reaction centers. FEBS Lett 570:171-4
Scott, Heather N; Laible, Philip D; Hanson, Deborah K (2003) Sequences of versatile broad-host-range vectors of the RK2 family. Plasmid 50:74-9