title: Multifaceted effects of ATP on cardiolipin-bound cytochrome c.
abstract: Using a collection of dye-labeled cytochrome c (cyt c) variants, we identify transformations of the heterogeneous cardiolipin (CL)-bound cyt c ensemble with added ATP. Distributions of dye-to-heme distances P(r) from time-resolved fluorescence resonance energy transfer show that ATP decreases the population of largely unfolded cyt c conformers, but its effects are distinct from those of a simple salt. The high peroxidase activity of CL-bound cyt c with added ATP suggests binding interactions that favor protein structures with the open heme pocket. Although ATP weakens cyt c-CL binding interactions, it also boosts the apoptosis-relevant peroxidase activity of CL-bound cyt c.
authors: Department of Chemistry, Dartmouth College, Hanover, NH 03755, USA.
authors: Erik J
authors: EJ
authors: Snider
authors: Julia
authors: J
authors: Muenzner
authors: Jason R
authors: JR
authors: Toffey
authors: Yuning
authors: Y
authors: Hong
authors: Ekaterina V
authors: EV
authors: Pletneva
mesh_terms: D000255:Adenosine Triphosphate / Q000378:metabolism*; D000818:Animals; D017209:Apoptosis; D002308:Cardiolipins / Q000378:metabolism*; D045304:Cytochromes c / Q000737:chemistry* / Q000378:metabolism; D006418:Heme / Q000378:metabolism*; D006736:Horses; D008081:Liposomes; D008958:Models, Molecular; D010084:Oxidation-Reduction; D009195:Peroxidase / Q000378:metabolism; D011485:Protein Binding; D011487:Protein Conformation; D013050:Spectrometry, Fluorescence
chemical_list: D002308:Cardiolipins; D008081:Liposomes; D006418:Heme; D000255:Adenosine Triphosphate; D045304:Cytochromes c; D009195:Peroxidase