Time-resolved neutron scattering provides new insight into protein substrate processing by a AAA+ unfoldase

• DOI: 10.1038/srep40948
• Publication Date: 2017-01-19T14:19:51Z
• Authors: Ziad Ibrahim; Anne Martel; Martine Moulin; Henry S. Kim; Michael Härtlein; Bruno Franzetti; Frank Gabel
• Keywords: 0301 basic medicine; 570; Protein Folding; [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry, Molecular Biology/Structural Biology [q-bio.BM]; Molecular Biology/Structural Biology [q-bio.BM]; Protein Conformation; Green Fluorescent Proteins; 540; Archaea; [SDV.BBM.BS]Life Sciences [q-bio]/Biochemistry; Article; 03 medical and health sciences; Scattering, Small Angle; ATPases Associated with Diverse Cellular Activities

We present a combination of small-angle neutron scattering, deuterium labelling and contrast variation, temperature activation fluorescence spectroscopy as novel approach to obtain time-resolved, structural data individually from macromolecular complexes their substrates during active biochemical reactions. The allowed us monitor the mechanical unfolding green fluorescent protein model substrate by archaeal AAA+ PAN unfoldase on sub-minute time scale. Concomitant with its substrate, complex underwent an energy-dependent transition relaxed contracted conformation, followed slower expansion initial state at end reaction. results support in which AAA ATPases unfold reversible power stroke mechanism involving several subunits demonstrate general utility this time-resolved for studying molecular kinetics multiple remodelling