Summary information and primary citation
- PDB-id
-
4l62;
DSSR-derived features in text and
JSON formats; DNAproDB
- Class
- transcription-DNA
- Method
- X-ray (2.9 Å)
- Summary
- Crystal structure of pseudomonas aeruginosa
transcriptional regulator pa2196 bound to its operator
DNA
- Reference
-
Kim Y, Kang Y, Choe J (2013): "Crystal
structure of Pseudomonas aeruginosa transcriptional
regulator PA2196 bound to its operator DNA."
Biochem.Biophys.Res.Commun.,
440, 317-321. doi: 10.1016/j.bbrc.2013.09.074.
- Abstract
- Pseudomonas aeruginosa is a major opportunistic human
pathogen. PA2196 from P. aeruginosa is a member of TetR
family of transcriptional repressors, which is involved in
adaptation to environmental changes as well as bacterial
antibiotic resistance. PA2196 consists of nine α-helical
bundles divided into two separate domains. The N-terminal
domain, called the DNA-binding domain, is composed of
helices α1-α3 and has a helix-turn-helix motif. The
C-terminal domain, called the ligand-binding domain, has a
hydrophobic pocket for ligand binding. Here, PA2196 was
shown to bind to a 25 bp semi-palindromic dsDNA located in
the upstream region of its own gene. The crystal structure
of the PA2196-25mer dsDNA complex determined at a
resolution of 2.9 Å revealed that two dimers of PA2196
bound to one dsDNA, with each monomer interacting with the
major groove of DNA. Especially, residues in helix α3,
including Lys41, Gly42, Ser43, and Tyr45, interacted mainly
with the base and phosphate backbone of dsDNA. PA2196
underwent large conformational changes upon DNA binding, as
the distances between DNA-binding domains measured between
two G42s in subunits A and B decreased from 41.7 Å to 36.8
Å. Our crystal structure of PA2196-25mer dsDNA complex
revealed that PA2196 is similar to QacR in that two dimers
bound to one dsDNA through specific interactions.
