3RL6

Crystal structure of the archaeal asparagine synthetase A complexed with L-Asparagine and Adenosine monophosphate

3RL6 の概要

• エントリーDOI: 10.2210/pdb3rl6/pdb
• 分子名称: Archaeal asparagine synthetase A, ASPARAGINE, ADENOSINE MONOPHOSPHATE, ... (5 entities in total)
• 機能のキーワード: amp and asn binding, seven stranded antiparallel beta-sheet, ligase
• 由来する生物種: Pyrococcus abyssi
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 69245.71

構造登録者

Blaise, M.,Frechin, M.,Charron, C.,Roy, H.,Sauter, C.,Lorber, B.,Olieric, V.,Kern, D. (登録日: 2011-04-19, 公開日: 2011-08-17, 最終更新日: 2024-02-28)

主引用文献

Blaise, M.,Frechin, M.,Olieric, V.,Charron, C.,Sauter, C.,Lorber, B.,Roy, H.,Kern, D.
Crystal Structure of the Archaeal Asparagine Synthetase: Interrelation with Aspartyl-tRNA and Asparaginyl-tRNA Synthetases.
J.Mol.Biol., 412:437-452, 2011

PubMed Abstract: Asparagine synthetase A (AsnA) catalyzes asparagine synthesis using aspartate, ATP, and ammonia as substrates. Asparagine is formed in two steps: the β-carboxylate group of aspartate is first activated by ATP to form an aminoacyl-AMP before its amidation by a nucleophilic attack with an ammonium ion. Interestingly, this mechanism of amino acid activation resembles that used by aminoacyl-tRNA synthetases, which first activate the α-carboxylate group of the amino acid to form also an aminoacyl-AMP before they transfer the activated amino acid onto the cognate tRNA. In a previous investigation, we have shown that the open reading frame of Pyrococcus abyssi annotated as asparaginyl-tRNA synthetase (AsnRS) 2 is, in fact, an archaeal asparagine synthetase A (AS-AR) that evolved from an ancestral aspartyl-tRNA synthetase (AspRS). We present here the crystal structure of this AS-AR. The fold of this protein is similar to that of bacterial AsnA and resembles the catalytic cores of AspRS and AsnRS. The high-resolution structures of AS-AR associated with its substrates and end-products help to understand the reaction mechanism of asparagine formation and release. A comparison of the catalytic core of AS-AR with those of archaeal AspRS and AsnRS and with that of bacterial AsnA reveals a strong conservation. This study uncovers how the active site of the ancestral AspRS rearranged throughout evolution to transform an enzyme activating the α-carboxylate group into an enzyme that is able to activate the β-carboxylate group of aspartate, which can react with ammonia instead of tRNA.

PubMed: 21820443
DOI: 10.1016/j.jmb.2011.07.050

実験手法

X-RAY DIFFRACTION (2 Å)