This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. Primary support for the subproject and the subproject's principal investigator may have been provided by other sources, including other NIH sources. The Total Cost listed for the subproject likely represents the estimated amount of Center infrastructure utilized by the subproject, not direct funding provided by the NCRR grant to the subproject or subproject staff. Thioredoxin proteins are important for maintaining the proper thiol redox state in cells. We are studying thioredoxinsw, and their interactions with thioredoxin reductases, from bacteria that are considered drug targets. To this end, we are determining the 3-dimensional structures of these thioredoxin proteins, and exploring their interactions (binding surfaces) with thioredoxin reductase partners.This, and other protects, are also focused on drug design, and studies of protein-ligand interactions to guide drug design. This involves NMR analysis of protein ligand complexes, including ligands that are designed using "fragment-assembly" techniques that my lab specializes in. Besides characterizing binding interfaces, we are also interested in changes to dynamic state of the protein and ligand, upon binding.