title: Binding Site Recognition and Docking Dynamics of a Single Electron Transport Protein: Cytochrome c2.
abstract: Small diffusible redox proteins facilitate electron transfer in respiration and photosynthesis by alternately binding to their redox partners and integral membrane proteins and exchanging electrons. Diffusive search, recognition, binding, and unbinding of these proteins often amount to kinetic bottlenecks in cellular energy conversion, but despite the availability of structures and intense study, the physical mechanisms controlling redox partner interactions remain largely unknown. The present molecular dynamics study provides an all-atom description of the cytochrome c2-docked bc1 complex in Rhodobacter sphaeroides in terms of an ensemble of favorable docking conformations and reveals an intricate series of conformational changes that allow cytochrome c2 to recognize the bc1 complex and bind or unbind in a redox state-dependent manner. In particular, the role of electron transfer in triggering a molecular switch and in altering water-mediated interface mobility, thereby strengthening and weakening complex formation, is described. The results resolve long-standing discrepancies between structural and functional data.
authors: Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , 405 North Mathews Avenue, Urbana, Illinois 61801, United States.
authors: Abhishek
authors: A
authors: Singharoy
authors: Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , 405 North Mathews Avenue, Urbana, Illinois 61801, United States.|Department of Physics, University of Illinois at Urbana-Champaign , 1110 West Green Street, Urbana, Illinois 61801, United States.
authors: Angela M
authors: AM
authors: Barragan
authors: Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , 405 North Mathews Avenue, Urbana, Illinois 61801, United States.|Department of Biochemistry, University of Illinois Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
authors: Sundarapandian
authors: S
authors: Thangapandian
authors: Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , 405 North Mathews Avenue, Urbana, Illinois 61801, United States.|Department of Biochemistry, University of Illinois Urbana-Champaign , 600 South Mathews Avenue, Urbana, Illinois 61801, United States.
authors: Emad
authors: E
authors: Tajkhorshid
authors: Beckman Institute for Advanced Science and Technology, University of Illinois at Urbana-Champaign , 405 North Mathews Avenue, Urbana, Illinois 61801, United States.|Department of Physics, University of Illinois at Urbana-Champaign , 1110 West Green Street, Urbana, Illinois 61801, United States.
authors: Klaus
authors: K
authors: Schulten
mesh_terms: D001665:Binding Sites; D003198:Computer Simulation; D045362:Cytochromes c2 / Q000737:chemistry*; D004579:Electron Transport / Q000502:physiology; D008956:Models, Chemical; D008958:Models, Molecular; D011485:Protein Binding; D011487:Protein Conformation; D012242:Rhodobacter sphaeroides / Q000201:enzymology*; D055672:Static Electricity
chemical_list: D045362:Cytochromes c2