6ABV

Crystal structure of citrate synthase (Msed_0281) from Metallosphaera sedula

6ABV の概要

• エントリーDOI: 10.2210/pdb6abv/pdb
• 分子名称: Citrate synthase, GLYCEROL (3 entities in total)
• 機能のキーワード: citrate synthase, metallosphaera sedula, transferase
• 由来する生物種: Metallosphaera sedula (strain ATCC 51363 / DSM 5348 / JCM 9185 / NBRC 15509 / TH2)
• タンパク質・核酸の鎖数: 1
• 化学式量合計: 43813.92

構造登録者

Lee, S.-H.,Kim, K.-J. (登録日: 2018-07-24, 公開日: 2019-01-16, 最終更新日: 2023-11-22)

主引用文献

Lee, S.H.,Kim, K.J.
Crystal structure and biochemical properties of msed_0281, the citrate synthase from Metallosphaera sedula.
Biochem. Biophys. Res. Commun., 509:722-727, 2019

PubMed Abstract: Metallosphaera sedula is a thermoacidophilic archaeon that has carbon fixation ability using the 3-hydroxypropionate/4-hydroxybutyrate(3-HP/4-HB) cycle, and has an incomplete TCA cycle to produce necessary biosynthetic precursors. The citrate synthase from M. sedula (MsCS) is an enzyme involved in the first step of the incomplete TCA cycle, catalyzing the conversion of oxaloacetate and acetyl-CoA into citrate and coenzyme A. To investigate the molecular mechanism of MsCS, we determined its crystal structure at 1.8 Å resolution. As other known CSs, MsCS functions as a dimer, and each monomer consists of two domains, a large domain and a small domain. We also determined the structure of the complex with acetyl-CoA and revealed the acetyl-CoA binding mode of MsCS. Structural comparison of MsCS with another CS in complex with oxaloacetate enabled us to predict the oxaloacetate binding site. Moreover, we performed inhibitory kinetic analyses of MsCS, and showed that the protein is inhibited by citrate and ATP by competitive and non-competitive inhibition modes, respectively, but not by NADH. Based on these results, we suggest that MsCS belongs to the type-I CS with structural and biochemical properties similar to those of CSs involved in the conventional TCA cycle.

PubMed: 30611567
DOI: 10.1016/j.bbrc.2018.12.172

実験手法

X-RAY DIFFRACTION (1.8 Å)