4YIW

DIHYDROOROTASE FROM BACILLUS ANTHRACIS WITH SUBSTRATE BOUND

4YIW の概要

• エントリーDOI: 10.2210/pdb4yiw/pdb
• 関連するPDBエントリー: 3MPG
• 分子名称: Dihydroorotase, ZINC ION, N-CARBAMOYL-L-ASPARTATE, ... (4 entities in total)
• 機能のキーワード: hydrolase
• 由来する生物種: Bacillus anthracis
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 99138.13

構造登録者

Lei, H.,Santarsiero, B.D.,Rice, A.J.,Lee, H.,Johnson, M.E. (登録日: 2015-03-02, 公開日: 2016-08-10, 最終更新日: 2023-09-27)

主引用文献

Rice, A.J.,Lei, H.,Santarsiero, B.D.,Lee, H.,Johnson, M.E.
Ca-asp bound X-ray structure and inhibition of Bacillus anthracis dihydroorotase (DHOase).
Bioorg.Med.Chem., 24:4536-4543, 2016

PubMed Abstract: Dihydroorotase (DHOase) is the third enzyme in the de novo pyrimidine synthesis pathway and is responsible for the reversible cyclization of carbamyl-aspartate (Ca-asp) to dihydroorotate (DHO). DHOase is further divided into two classes based on several structural characteristics, one of which is the length of the flexible catalytic loop that interacts with the substrate, Ca-asp, regulating the enzyme activity. Here, we present the crystal structure of Class I Bacillus anthracis DHOase with Ca-asp in the active site, which shows the peptide backbone of glycine in the shorter loop forming the necessary hydrogen bonds with the substrate, in place of the two threonines found in Class II DHOases. Despite the differences in the catalytic loop, the structure confirms that the key interactions between the substrate and active site residues are similar between Class I and Class II DHOase enzymes, which we further validated by mutagenesis studies. B. anthracis DHOase is also a potential antibacterial drug target. In order to identify prospective inhibitors, we performed high-throughput screening against several libraries using a colorimetric enzymatic assay and an orthogonal fluorescence thermal binding assay. Surface plasmon resonance was used for determining binding affinity (KD) and competition analysis with Ca-asp. Our results highlight that the primary difference between Class I and Class II DHOase is the catalytic loop. We also identify several compounds that can potentially be further optimized as potential B. anthracis inhibitors.

PubMed: 27499369
DOI: 10.1016/j.bmc.2016.07.055

実験手法

X-RAY DIFFRACTION (2.45 Å)