A structural pathway for signaling in the E46Q mutant of photoactive yellow protein.

Published

Journal Article

In the bacterial photoreceptor photoactive yellow protein (PYP), absorption of blue light by its chromophore leads to a conformational change in the protein associated with differential signaling activity, as it executes a reversible photocycle. Time-resolved Laue crystallography allows structural snapshots (as short as 150 ps) of high crystallographic resolution (approximately 1.6 A) to be taken of a protein as it functions. Here, we analyze by singular value decomposition a comprehensive time-resolved crystallographic data set of the E46Q mutant of PYP throughout the photocycle spanning 10 ns-100 ms. We identify and refine the structures of five distinct intermediates and provide a plausible chemical kinetic mechanism for their inter conversion. A clear structural progression is visible in these intermediates, in which a signal generated at the chromophore propagates through a distinct structural pathway of conserved residues and results in structural changes near the N terminus, over 20 A distant from the chromophore.

Full Text

Duke Authors

Cited Authors

  • Rajagopal, S; Anderson, S; Srajer, V; Schmidt, M; Pahl, R; Moffat, K

Published Date

  • January 2005

Published In

Volume / Issue

  • 13 / 1

Start / End Page

  • 55 - 63

PubMed ID

  • 15642261

Pubmed Central ID

  • 15642261

International Standard Serial Number (ISSN)

  • 0969-2126

Digital Object Identifier (DOI)

  • 10.1016/j.str.2004.10.016

Language

  • eng

Conference Location

  • United States