PDBsum entry 1k66

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Signaling protein PDB id
Protein chains
149 a.a. *
Waters ×393
* Residue conservation analysis
PDB id:
Name: Signaling protein
Title: Crystal structure of the cyanobacterial phytochrome response regulator, rcpb
Structure: Phytochrome response regulator rcpb. Chain: a, b. Engineered: yes
Source: Tolypothrix sp. Pcc 7601. Organism_taxid: 1188. Gene: af309560. Expressed in: escherichia coli. Expression_system_taxid: 562.
Biol. unit: Dimer (from PQS)
1.75Å     R-factor:   0.216     R-free:   0.250
Authors: C.Benda,C.Scheufler,N.Tandeau De Marsac,W.Gaertner
Key ref: C.Benda et al. (2004). Crystal structures of two cyanobacterial response regulators in apo- and phosphorylated form reveal a novel dimerization motif of phytochrome-associated response regulators. Biophys J, 87, 476-487. PubMed id: 15240481
15-Oct-01     Release date:   16-Dec-03    
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Protein chains
Pfam   ArchSchema ?
Q8RTM8  (Q8RTM8_9CYAN) -  Response regulator
149 a.a.
149 a.a.*
Key:    PfamA domain  Secondary structure  CATH domain
* PDB and UniProt seqs differ at 1 residue position (black cross)

 Gene Ontology (GO) functional annotation 
  GO annot!
  Biological process     intracellular signal transduction   2 terms 
  Biochemical function     two-component response regulator activity     1 term  


Biophys J 87:476-487 (2004)
PubMed id: 15240481  
Crystal structures of two cyanobacterial response regulators in apo- and phosphorylated form reveal a novel dimerization motif of phytochrome-associated response regulators.
C.Benda, C.Scheufler, N.Tandeau de Marsac, W.Gärtner.
The structures of two response regulators (RRs) from the cyanobacterium Calothrix PCC7601, RcpA and RcpB, were solved to 1.9- and 1.75-A resolution, respectively. RcpA was found in phosphorylated and RcpB in nonphosphorylated form. Both RRs are members of phytochrome-associated, light-sensing two-component signal transduction pathways, based on histidine kinase-mediated receptor autophosphorylation and phosphorelay to a RR. Despite the overall folding similarity to CheY-type RRs ((beta/alpha)(5)-motif), RcpA and RcpB form homodimers, irrespective of their phosphorylation state, giving insight into a signal transduction putatively different from that of other known RRs. Dimerization is accomplished by a C-terminal extension of the RR polypeptide chain, and the surface formed by H4, beta 5, and H5, which constitute a hydrophobic contact area with distinct interactions between residues of either subunit. Sequence alignments reveal that the identified dimerization motif is archetypal for phytochrome-associated RRs, making them a novel subgroup of CheY-type RRs. The protein structures of RcpA and RcpB are compared to the recently presented protein structure of Rcp1 from Synechocystis.

Literature references that cite this PDB file's key reference

  PubMed id Reference
20080056 R.Gao, and A.M.Stock (2010).
Molecular strategies for phosphorylation-mediated regulation of response regulator activity.
  Curr Opin Microbiol, 13, 160-167.  
19808667 S.Sharda, M.S.Koay, Y.J.Kim, M.Engelhard, and W.Gärtner (2009).
A non-hydrolyzable ATP derivative generates a stable complex in a light-inducible two-component system.
  J Biol Chem, 284, 33999-34004.  
17388813 B.Quest, T.Hübschmann, S.Sharda, N.Tandeau de Marsac, and W.Gärtner (2007).
Homologous expression of a bacterial phytochrome. The cyanobacterium Fremyella diplosiphon incorporates biliverdin as a genuine, functional chromophore.
  FEBS J, 274, 2088-2098.  
17067849 J.Purschwitz, S.Müller, C.Kastner, and R.Fischer (2006).
Seeing the rainbow: light sensing in fungi.
  Curr Opin Microbiol, 9, 566-571.  
16788205 K.I.Varughese, I.Tsigelny, and H.Zhao (2006).
The crystal structure of beryllofluoride Spo0F in complex with the phosphotransferase Spo0B represents a phosphotransfer pretransition state.
  J Bacteriol, 188, 4970-4977.
PDB code: 2ftk
16816192 R.Gao, A.Mukhopadhyay, F.Fang, and D.G.Lynn (2006).
Constitutive activation of two-component response regulators: characterization of VirG activation in Agrobacterium tumefaciens.
  J Bacteriol, 188, 5204-5211.  
16321923 K.I.Varughese (2005).
Conformational changes of Spo0F along the phosphotransfer pathway.
  J Bacteriol, 187, 8221-8227.  
15817384 K.J.Hellingwerf (2005).
Bacterial observations: a rudimentary form of intelligence?
  Trends Microbiol, 13, 152-158.  
The most recent references are shown first. Citation data come partly from CiteXplore and partly from an automated harvesting procedure. Note that this is likely to be only a partial list as not all journals are covered by either method. However, we are continually building up the citation data so more and more references will be included with time. Where a reference describes a PDB structure, the PDB code is shown on the right.