5MBE

Structure of a bacterial light-regulated adenylyl cylcase


Experimental Data Snapshot

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.196 

wwPDB Validation 3D Report Full Report


This is version 1.1 of the entry. See complete history

Literature

Photoactivation Mechanism of a Bacterial Light-Regulated Adenylyl Cyclase.

Lindner, R.Hartmann, E.Tarnawski, M.Winkler, A.Frey, D.Reinstein, J.Meinhart, A.Schlichting, I.

(2017) J. Mol. Biol. 429: 1336-1351

  • DOI: 10.1016/j.jmb.2017.03.020
  • Primary Citation of Related Structures:  

  • PubMed Abstract: 
  • Light-regulated enzymes enable organisms to quickly respond to changing light conditions. We characterize a photoactivatable adenylyl cyclase (AC) from Beggiatoa sp. (bPAC) that translates a blue light signal into the production of the second messeng ...

    Light-regulated enzymes enable organisms to quickly respond to changing light conditions. We characterize a photoactivatable adenylyl cyclase (AC) from Beggiatoa sp. (bPAC) that translates a blue light signal into the production of the second messenger cyclic AMP. bPAC contains a BLUF photoreceptor domain that senses blue light using a flavin chromophore, linked to an AC domain. We present a dark state crystal structure of bPAC that closely resembles the recently published structure of the homologous OaPAC from Oscillatoria acuminata. To elucidate the structural mechanism of light-dependent AC activation by the BLUF domain, we determined the crystal structures of illuminated bPAC and of a pseudo-lit state variant. We use hydrogen-deuterium exchange measurements of secondary structure dynamics and hypothesis-driven point mutations to trace the activation pathway from the chromophore in the BLUF domain to the active site of the cyclase. The structural changes are relayed from the residues interacting with the excited chromophore through a conserved kink of the BLUF β-sheet to a tongue-like extrusion of the AC domain that regulates active site opening and repositions catalytic residues. Our findings not only show the specific molecular pathway of photoactivation in BLUF-regulated ACs but also have implications for the general understanding of signaling in BLUF domains and of the activation of ACs.


    Organizational Affiliation

    Max Planck Institute for Medical Research, Jahnstr, 29, 69120 Heidelberg, Germany. Electronic address: ilme.schlichting@mpimf-heidelberg.mpg.de.,Max Planck Institute for Medical Research, Jahnstr, 29, 69120 Heidelberg, Germany.




Macromolecules

Find similar proteins by: Sequence  |  Structure

Entity ID: 1
MoleculeChainsSequence LengthOrganismDetails
Beta subunit of photoactivated adenylyl cyclase
A, B
353Beggiatoa sp. PSMutation(s): 0 
Find proteins for A7BT71 (Beggiatoa sp. PS)
Go to UniProtKB:  A7BT71
Small Molecules
Ligands 1 Unique
IDChainsName / Formula / InChI Key2D Diagram3D Interactions
FMN
Query on FMN

Download SDF File 
Download CCD File 
A, B
FLAVIN MONONUCLEOTIDE
RIBOFLAVIN MONOPHOSPHATE
C17 H21 N4 O9 P
FVTCRASFADXXNN-SCRDCRAPSA-N
 Ligand Interaction
Experimental Data & Validation

Experimental Data

  • Method: X-RAY DIFFRACTION
  • Resolution: 2.4 Å
  • R-Value Free: 0.231 
  • R-Value Work: 0.196 
  • Space Group: P 1
Unit Cell:
Length (Å)Angle (°)
a = 47.480α = 105.79
b = 56.310β = 103.67
c = 77.450γ = 102.70
Software Package:
Software NamePurpose
XSCALEdata scaling
PHASERphasing
PDB_EXTRACTdata extraction
PHENIXrefinement
XDSdata reduction

Structure Validation

View Full Validation Report or Ramachandran Plots



Entry History & Funding Information

Deposition Data


Funding OrganizationLocationGrant Number
DFGGermanyFOR1279

Revision History 

  • Version 1.0: 2017-04-05
    Type: Initial release
  • Version 1.1: 2017-05-03
    Type: Database references