1KG8

X-ray structure of an early-M intermediate of bacteriorhodopsin


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.217 
  • R-Value Work: 0.168 

wwPDB Validation 3D Report Full Report


This is version 1.2 of the entry. See complete history

Literature

Structure of an early intermediate in the M-state phase of the bacteriorhodopsin photocycle.

Facciotti, M.T.Rouhani, S.Burkard, F.T.Betancourt, F.M.Downing, K.H.Rose, R.B.McDermott, G.Glaeser, R.M.

(2001) Biophys.J. 81: 3442-3455

  • DOI: 10.1016/S0006-3495(01)75976-0
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • The structure of an early M-intermediate of the wild-type bacteriorhodopsin photocycle formed by actinic illumination at 230 K has been determined by x-ray crystallography to a resolution of 2.0 A. Three-dimensional crystals were trapped by illuminat ...

    The structure of an early M-intermediate of the wild-type bacteriorhodopsin photocycle formed by actinic illumination at 230 K has been determined by x-ray crystallography to a resolution of 2.0 A. Three-dimensional crystals were trapped by illuminating with actinic light at 230 K, followed by quenching in liquid nitrogen. Amide I, amide II, and other infrared absorption bands, recorded from single bacteriorhodopsin crystals, confirm that the M-substate formed represents a structure that occurs early after deprotonation of the Schiff base. Rotation about the retinal C13-C14 double bond appears to be complete, but a relatively large torsion angle of 26 degrees is still seen for the C14-C15 bond. The intramolecular stress associated with the isomerization of retinal and the subsequent deprotonation of the Schiff base generates numerous small but experimentally measurable structural changes within the protein. Many of the residues that are displaced during the formation of the late M (M(N)) substate formed by three-dimensional crystals of the D96N mutant (Luecke et al., 1999b) are positioned, in early M, between their resting-state locations and the ones which they will adopt at the end of the M phase. The relatively small magnitude of atomic displacements observed in this intermediate, and the well-defined positions adopted by nearly all of the atoms in the structure, may make the formation of this structure favorable to model (simulate) by molecular dynamics.


    Organizational Affiliation

    Graduate Group in Biophysics, Lawrence Berkeley National Laboratory, University of California, Berkeley, California 94720, USA.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
bacteriorhodopsin
A
231Halobacterium salinarum (strain ATCC 700922 / JCM 11081 / NRC-1)Gene Names: bop
Membrane protein
mpstruct
Group: 
TRANSMEMBRANE PROTEINS: ALPHA-HELICAL
Sub Group: 
Bacterial and Algal Rhodopsins
Protein: 
Bacteriorhodopsin (BR)
Find proteins for P02945 (Halobacterium salinarum (strain ATCC 700922 / JCM 11081 / NRC-1))
Go to UniProtKB:  P02945
Small Molecules
Ligands 2 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
LI1
Query on LI1

Download SDF File 
Download CCD File 
A
1-[2,6,10.14-TETRAMETHYL-HEXADECAN-16-YL]-2-[2,10,14-TRIMETHYLHEXADECAN-16-YL]GLYCEROL
LIPID FRAGMENT
C42 H86 O3
YERVUJAKCNBGCR-BIHSMRAKSA-N
 Ligand Interaction
RET
Query on RET

Download SDF File 
Download CCD File 
A
RETINAL
C20 H28 O
NCYCYZXNIZJOKI-OVSJKPMPSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2 Å
  • R-Value Free: 0.217 
  • R-Value Work: 0.168 
  • Space Group: P 63
Unit Cell:
Length (Å)Angle (°)
a = 60.745α = 90.00
b = 60.745β = 90.00
c = 108.240γ = 120.00
Software Package:
Software NamePurpose
SCALEPACKdata scaling
SHELXL-97refinement

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History 

Deposition Data

Revision History 

  • Version 1.0: 2001-12-05
    Type: Initial release
  • Version 1.1: 2008-04-27
    Type: Version format compliance
  • Version 1.2: 2011-07-13
    Type: Derived calculations, Version format compliance