7CV2

Crystal structure of B. halodurans NiaR in niacin-bound form

Summary for 7CV2

• Entry DOI: 10.2210/pdb7cv2/pdb
• Descriptor: Transcriptional regulator NiaR, NICOTINIC ACID, ZINC ION, ... (4 entities in total)
• Functional Keywords: niar, transcription factor, transction, structural protein
• Biological source: Bacillus halodurans (strain ATCC BAA-125 / DSM 18197 / FERM 7344 / JCM 9153 / C-125)
• Total number of polymer chains: 1
• Total formula weight: 20109.50

Authors

Lee, J.Y.,Lee, D.W.,Park, Y.W.,Lee, M.Y.,Jeong, K.H. (deposition date: 2020-08-25, release date: 2020-12-16, Last modification date: 2023-11-29)

Primary citation

Lee, D.W.,Park, Y.W.,Lee, M.Y.,Jeong, K.H.,Lee, J.Y.
Structural analysis and insight into effector binding of the niacin-responsive repressor NiaR from Bacillus halodurans.
Sci Rep, 10:21039-21039, 2020

PubMed Abstract: The niacin-responsive repressor, NiaR, is transcriptional repressor of certain nicotinamide adenine dinucleotide (NAD) biosynthetic genes in response to an increase in niacin levels. NAD is a vital molecule involved in various cellular redox reactions as an electron donor or electron acceptor. The NiaR family is conserved broadly in the Bacillus/Clostridium group, as well as in the Fusobacteria and Thermotogales lineages. The NiaR structure consists of two domains: an N-terminal DNA-binding domain, and a C-terminal regulation domain containing a metal-binding site. In this paper, we report the crystal structures of apo and niacin-bound forms of NiaR from Bacillus halodurans (BhNiaR). The analysis of metal-binding and niacin-binding sites through the apo and niacin-bound structures is described. Each N- and C-terminal domain structure of BhNiaR is almost identical with NiaR from Thermotoga maritima, but the overall domain arrangement is quite different. A zinc ion is fully occupied in each subunit with well-conserved residues in the C-terminal domain. Niacin is also located at a hydrophobic pocket near the zinc ion in the C-terminal domain.

PubMed: 33273654
DOI: 10.1038/s41598-020-78148-x

Experimental method

X-RAY DIFFRACTION (1.802 Å)