3K0E

Crystal structure of the phosphorylation-site mutant T426N of the KaiC circadian clock protein

Summary for 3K0E

• Entry DOI: 10.2210/pdb3k0e/pdb
• Related: 3DVL 3JZM 3K09 3K0A 3K0C 3K0F
• Descriptor: Circadian clock protein kinase KaiC, MAGNESIUM ION, ADENOSINE-5'-TRIPHOSPHATE, ... (4 entities in total)
• Functional Keywords: kaic, circadian clock protein, kinase, hexamer, atp-binding, biological rhythms, dna-binding, magnesium, metal-binding, nucleotide-binding, phosphoprotein, repressor, serine/threonine-protein kinase, transcription, transcription regulation, transferase
• Biological source: Synechococcus elongatus PCC 7942 (Anacystis nidulans R2)
• Total number of polymer chains: 6
• Total formula weight: 356046.63

Authors

Pattanayek, R.,Egli, M.,Pattanayek, S. (deposition date: 2009-09-24, release date: 2010-03-31, Last modification date: 2024-11-06)

Primary citation

Pattanayek, R.,Mori, T.,Xu, Y.,Pattanayek, S.,Johnson, C.H.,Egli, M.
Structures of KaiC Circadian Clock Mutant Proteins: A New Phosphorylation Site at T426 and Mechanisms of Kinase, ATPase and Phosphatase.
Plos One, 4:e7529-e7529, 2009

PubMed Abstract: The circadian clock of the cyanobacterium Synechococcus elongatus can be reconstituted in vitro by three proteins, KaiA, KaiB and KaiC. Homo-hexameric KaiC displays kinase, phosphatase and ATPase activities; KaiA enhances KaiC phosphorylation and KaiB antagonizes KaiA. Phosphorylation and dephosphorylation of the two known sites in the C-terminal half of KaiC subunits, T432 and S431, follow a strict order (TS-->pTS-->pTpS-->TpS-->TS) over the daily cycle, the origin of which is not understood. To address this void and to analyze the roles of KaiC active site residues, in particular T426, we determined structures of single and double P-site mutants of S. elongatus KaiC.

PubMed: 19956664
DOI: 10.1371/journal.pone.0007529

Experimental method

X-RAY DIFFRACTION (3.2 Å)