4HDK

Crystal Structure of ArsAB in Complex with Phloroglucinol

4HDK の概要

• エントリーDOI: 10.2210/pdb4hdk/pdb
• 関連するPDBエントリー: 4HDM 4HDN 4HDR 4HDS
• 分子名称: ArsA, ArsB, CHLORIDE ION, ... (6 entities in total)
• 機能のキーワード: transferase, transferase-transferase inhibitor complex, transferase/transferase inhibitor
• 由来する生物種: Sporomusa ovata; 詳細
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 73015.73

構造登録者

Newmister, S.A.,Chan, C.H.,Escalante-Semerena, J.C.,Rayment, I. (登録日: 2012-10-02, 公開日: 2012-10-24, 最終更新日: 2024-02-28)

主引用文献

Newmister, S.A.,Chan, C.H.,Escalante-Semerena, J.C.,Rayment, I.
Structural Insights into the Function of the Nicotinate Mononucleotide:phenol/p-cresol Phosphoribosyltransferase (ArsAB) Enzyme from Sporomusa ovata.
Biochemistry, 51:8571-8582, 2012

PubMed Abstract: Cobamides (Cbas) are cobalt (Co) containing tetrapyrrole-derivatives involved in enzyme-catalyzed carbon skeleton rearrangements, methyl-group transfers, and reductive dehalogenation. The biosynthesis of cobamides is complex and is only performed by some bacteria and achaea. Cobamides have an upper (Coβ) ligand (5'-deoxyadenosyl or methyl) and a lower (Coα) ligand base that contribute to the axial Co coordinations. The identity of the lower Coα ligand varies depending on the organism synthesizing the Cbas. The homoacetogenic bacterium Sporomusa ovata synthesizes two unique phenolic cobamides (i.e., Coα-(phenolyl/p-cresolyl)cobamide), which are used in the catabolism of methanol and 3,4-dimethoxybenzoate by this bacterium. The S. ovata ArsAB enzyme activates a phenolic lower ligand prior to its incorporation into the cobamide. ArsAB consists of two subunits, both of which are homologous (∼35% identity) to the well-characterized Salmonella enterica CobT enzyme, which transfers nitrogenous bases such as 5,6-dimethylbenzimidazole (DMB) and adenine, but cannot utilize phenolics. Here we report the three-dimensional structure of ArsAB, which shows that the enzyme forms a pseudosymmetric heterodimer, provide evidence that only the ArsA subunit has base:phosphoribosyl-transferase activity, and propose a mechanism by which phenolic transfer is facilitated by an activated water molecule.

PubMed: 23039029
DOI: 10.1021/bi301142h

実験手法

X-RAY DIFFRACTION (1.5 Å)