U.S.-Japan Cooperative Science: Structure-Function Relationship in Hyperthermostable, Archaeal Rieske- Type Proteins

University Of Illinois At Urbana-Champaign, Urbana IL

Investigators

Abstract

9910113 Dikanov This award supports a three year collaborative research project between Professor Sergei Dikanov of the University of Illinois, Urbana-Champaign and Professor Toshio Iwasaki of the Nippon Medical School in Tokyo, Japan. The researchers will be undertaking a study of the structure-function relationship in hyperthermostable archael Rieske type protein. Iron-sulfur (Fe-S) proteins, widely represented in nature, exhibit reversible oxidation-reduction between different oxidation states of the iron-sulfur cluster. Because iron-sulfur proteins are engaged in electron transport, the redox potentials of the clusters are among the principal characteristics of their biological function. The project is devoted to the study structure-function relationships in two hyperthermostable, archael Rieske-type proteins: a) sulredoxin (SDX) of Sulfolobus sp. Strain 7; and b) archaeal Rieske-type ferredoxin (ARF) from a closely related organism, Sulfolobus solfataricus by advanced magnetic resonance techniques. It is proposed to investigate samples of reduced SDX and ARF as well as their mutants, to compare with the Rieske center in cytochrome bc1 complex, whose X-ray structure is available, and to characterize the cluster environment in detail including coordination of histidine and cysteine ligands, presence of hydrogen bonds and noncoordinated nitrogens, and accessibility of the solvent. The project brings together the efforts of two laboratories that have complementary expertise and research capabilities. Results of the research will provide fundamental information about the structural factors controlling the redox potentials in hyperthermostable, iron-sulfur proteins, and will have far reaching consequences in both basic and applied energy conversion systems involving more complex metallo-enzymes. The research would also have an impact across a wide spectrum of disciplines. This research advances international human resources through the participation of postdocs and graduate students. Through the exchange of ideas and technology, this project will broaden our base of basic knowledge and promote international understanding and cooperation. The researchers plan to publish results of the research in scientific journals and report on the findings at scientific meetings. The results will also be available on the www home page of the Illinois EPR center: http://ierc.scs.uiuc.edu and at the Center for Biophysics at the University of Illinois at: http://www.life.uiuc.edu/crofts/bc_complex_site 9910113 Dikanov This award supports a three year collaborative research project between Professor Sergei Dikanov of the University of Illinois, Urbana-Champaign and Professor Toshio Iwasaki of the Nippon Medical School in Tokyo, Japan. The researchers will be undertaking a study of the structure-function relationship in hyperthermostable archael Rieske type protein. Iron-sulfur (Fe-S) proteins, widely represented in nature, exhibit reversible oxidation-reduction between different oxidation states of the iron-sulfur cluster. Because iron-sulfur proteins are engaged in electron transport, the redox potentials of the clusters are among the principal characteristics of their biological function. The project is devoted to the study structure-function relationships in two hyperthermostable, archael Rieske-type proteins: a) sulredoxin (SDX) of Sulfolobus sp. Strain 7; and b) archaeal Rieske-type ferredoxin (ARF) from a closely related organism, Sulfolobus solfataricus by advanced magnetic resonance techniques. It is proposed to investigate samples of reduced SDX and ARF as well as their mutants, to compare with the Rieske center in cytochrome bc1 complex, whose X-ray structure is available, and to characterize the cluster environment in detail including coordination of histidine and cysteine ligands, presence of hydrogen bonds and noncoordinated nitrogens, and accessibility of the solvent. The project brings together the efforts of two laboratories that have complementary expertise and research capabilities. Results of the research will provide fundamental information about the structural factors controlling the redox potentials in hyperthermostable, iron-sulfur proteins, and will have far reaching consequences in both basic and applied energy conversion systems involving more complex metallo-enzymes. The research would also have an impact across a wide spectrum of disciplines. This research advances international human resources through the participation of postdocs and graduate students. Through the exchange of ideas and technology, this project will broaden our base of basic knowledge and promote international understanding and cooperation. The researchers plan to publish results of the research in scientific journals and report on the findings at scientific meetings. The results will also be available on the www home page of the Illinois EPR center: http://ierc.scs.uiuc.edu and at the Center for Biophysics at the University of Illinois at: http://www.life.uiuc.edu/crofts/bc_complex_site