6JNI

Crystal structure of the transcriptional regulator CadR from P. putida in complex with Zinc(II) and DNA

Summary for 6JNI

• Entry DOI: 10.2210/pdb6jni/pdb
• Descriptor: CadR, DNA (25-MER), ZINC ION, ... (4 entities in total)
• Functional Keywords: cadr, merr family, cadmium regulator, transcription, transcription-dna complex, transcription/dna
• Biological source: Pseudomonas putida (Arthrobacter siderocapsulatus); More
• Total number of polymer chains: 16
• Total formula weight: 195851.88

Authors

Liu, X.C.,Gan, J.H.,Chen, H. (deposition date: 2019-03-16, release date: 2019-09-25, Last modification date: 2023-11-22)

Primary citation

Liu, X.,Hu, Q.,Yang, J.,Huang, S.,Wei, T.,Chen, W.,He, Y.,Wang, D.,Liu, Z.,Wang, K.,Gan, J.,Chen, H.
Selective cadmium regulation mediated by a cooperative binding mechanism in CadR.
Proc.Natl.Acad.Sci.USA, 116:20398-20403, 2019

PubMed Abstract: Detoxification of the highly toxic cadmium element is essential for the survival of living organisms. CadR, a MerR family transcriptional regulator, has been reported to exhibit an ultraspecific response to the cadmium ion. Our crystallographic and spectroscopic studies reveal that the extra cadmium selectivity of CadR is mediated by the unexpected cooperation of thiolate-rich site I and histidine-rich site II. Cadmium binding in site I mediates the reorientation of protein domains and facilitates the assembly of site II. Subsequently, site II bridge-links 2 DNA binding domains through ligands His140/His145 in the C-terminal histidine-rich tail. With dynamic transit between 2 conformational states, this bridge could stabilize the regulator into an optimal conformation that is critical for enhancing the transcriptional activity of the cadmium detoxification system. Our results provide dynamic insight into how nature utilizes the unique cooperative binding mechanism in multisite proteins to recognize cadmium ions specifically.

PubMed: 31548408
DOI: 10.1073/pnas.1908610116

Experimental method

X-RAY DIFFRACTION (2.9 Å)