Role of active site conformational changes in photocycle activation of the AppA BLUF photoreceptor

Abstract

Photoreceptor proteins play a critical role in the light regulation of physiologically essential processes, including color vision, circadian rhythms, and photomovement. Photoexcitation of a chromophore bound to the photoreceptor protein leads to local conformational changes that propagate to distal regions of the protein and thereby drive vital chemical and physical changes. Understanding the fundamental mechanisms of these proteins is important for engineering systems that use light to control biological processes with high spatiotemporal resolution. In this study, computer simulations of a photoreceptor protein provide valuable insights into the active site conformations prior to and following photoexcitation. The position of a certain tryptophan residue, as well as the hydrogen-bonding pattern, is shown to impact the activation and efficiency of this photoreceptor.

Document Details

Document Type
Pub Defense Publication
Publication Date
Jan 30, 2017
Source ID
10.1073/pnas.1621393114

Entities

People

  • Puja Goyal
  • Sharon Hammes-Schiffer

Organizations

  • Air Force Office of Scientific Research
  • University of Illinois Urbana–Champaign

Tags

Readers

  • Circadian Sleep-Wake Regulation and Chronobiology
  • Molecular and Cellular Biochemistry
  • Vision Science/Vision Psychology/Cognitive Neuroscience.