6M09

The ligand-free structure of the chloroplast protein At3g03890

6M09 の概要

• エントリーDOI: 10.2210/pdb6m09/pdb
• 分子名称: AT3G03890 protein (2 entities in total)
• 機能のキーワード: heme binding protein, plant protein
• 由来する生物種: Arabidopsis thaliana (Mouse-ear cress)
• タンパク質・核酸の鎖数: 4
• 化学式量合計: 127857.49

構造登録者

Wang, J.,Liu, L. (登録日: 2020-02-20, 公開日: 2020-12-16, 最終更新日: 2023-11-29)

主引用文献

Wang, J.,Guo, Q.,Li, X.,Wang, X.,Liu, L.
The Arabidopsis locus AT3G03890 encodes a dimeric beta-barrel protein implicated in heme degradation.
Biochem.J., 2020

PubMed Abstract: Plant tetrapyrroles, including heme and bilins, are synthesized in plastids. Heme oxygenase (HO) catalyzes the oxidative cleavage of heme to the linear tetrapyrrole biliverdin as the initial step in bilin biosynthesis. Besides the canonical α-helical HO that is conserved from prokaryotes to human, a subfamily of non-canonical dimeric β-barrel HO has been found in bacteria. In this work, we discovered that the Arabidopsis locus AT3G03890 encodes a dimeric β-barrel protein that is structurally related to the putative non-canonical HO and is located in chloroplasts. The recombinant protein was able to bind and degrade heme in a manner different from known HO proteins. Crystal structure of the heme-protein complex reveals that the heme-binding site is in the interdimer interface and the heme iron is coordinated by a fixed water molecule. Our results identify a new protein that may function additionally in the tetrapyrrole biosynthetic pathway.

PubMed: 33284325
DOI: 10.1042/BCJ20200712

実験手法

X-RAY DIFFRACTION (2.101 Å)