6YSP

Arabidopsis aspartate transcarbamoylase complex with PALA and carbamoyl phosphate

6YSP の概要

• エントリーDOI: 10.2210/pdb6ysp/pdb
• 分子名称: PYRB, PHOSPHORIC ACID MONO(FORMAMIDE)ESTER, SULFATE ION, ... (6 entities in total)
• 機能のキーワード: transferase, chloroplast, pyrimidine de novo biosynthesis, plant protein
• 由来する生物種: Arabidopsis thaliana (thale cress)
• タンパク質・核酸の鎖数: 3
• 化学式量合計: 112847.31

構造登録者

Ramon Maiques, S.,Del Cano Ochoa, F.,Bellin, L.,Mohlmann, T. (登録日: 2020-04-23, 公開日: 2021-03-03, 最終更新日: 2024-01-24)

主引用文献

Bellin, L.,Del Cano-Ochoa, F.,Velazquez-Campoy, A.,Mohlmann, T.,Ramon-Maiques, S.
Mechanisms of feedback inhibition and sequential firing of active sites in plant aspartate transcarbamoylase.
Nat Commun, 12:947-947, 2021

PubMed Abstract: Aspartate transcarbamoylase (ATC), an essential enzyme for de novo pyrimidine biosynthesis, is uniquely regulated in plants by feedback inhibition of uridine 5-monophosphate (UMP). Despite its importance in plant growth, the structure of this UMP-controlled ATC and the regulatory mechanism remain unknown. Here, we report the crystal structures of Arabidopsis ATC trimer free and bound to UMP, complexed to a transition-state analog or bearing a mutation that turns the enzyme insensitive to UMP. We found that UMP binds and blocks the ATC active site, directly competing with the binding of the substrates. We also prove that UMP recognition relies on a loop exclusively conserved in plants that is also responsible for the sequential firing of the active sites. In this work, we describe unique regulatory and catalytic properties of plant ATCs that could be exploited to modulate de novo pyrimidine synthesis and plant growth.

PubMed: 33574254
DOI: 10.1038/s41467-021-21165-9

実験手法

X-RAY DIFFRACTION (1.38 Å)