4RKC

Psychrophilic aromatic amino acids aminotransferase from Psychrobacter sp. B6

4RKC の概要

• エントリーDOI: 10.2210/pdb4rkc/pdb
• 関連するPDBエントリー: 3FSL 3TAT 4F4E 4RKD
• 分子名称: Aromatic amino acid aminotransferase, MAGNESIUM ION, NITRATE ION, ... (5 entities in total)
• 機能のキーワード: aminotransferase, aromatic substrates, plp dependent enzyme, plp, transferase
• 由来する生物種: Psychrobacter sp. B6
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 89563.41

構造登録者

Bujacz, A.,Rutkiewicz-Krotewicz, M.,Bujacz, G.,Nowakowska-Sapota, K.,Turkiewicz, M. (登録日: 2014-10-12, 公開日: 2015-03-11, 最終更新日: 2023-09-20)

主引用文献

Bujacz, A.,Rutkiewicz-Krotewicz, M.,Nowakowska-Sapota, K.,Turkiewicz, M.
Crystal structure and enzymatic properties of a broad substrate-specificity psychrophilic aminotransferase from the Antarctic soil bacterium Psychrobacter sp. B6.
Acta Crystallogr. D Biol. Crystallogr., 71:632-645, 2015

PubMed Abstract: Aminotransferases (ATs) are enzymes that are commonly used in the chemical and pharmaceutical industries for the synthesis of natural and non-natural amino acids by transamination reactions. Currently, the easily accessible enzymes from mesophilic organisms are most commonly used; however, for economical and ecological reasons the utilization of aminotransferases from psychrophiles would be more advantageous, as their optimum reaction temperature is usually significantly lower than for the mesophilic ATs. Here, gene isolation, protein expression, purification, enzymatic properties and structural studies are reported for the cold-active aromatic amino-acid aminotransferase (PsyArAT) from Psychrobacter sp. B6, a psychrotrophic, Gram-negative strain from Antarctic soil. Preliminary computational analysis indicated dual functionality of the enzyme through the ability to utilize both aromatic amino acids and aspartate as substrates. This postulation was confirmed by enzymatic activity tests, which showed that it belonged to the class EC 2.6.1.57. The first crystal structures of a psychrophilic aromatic amino-acid aminotransferase have been determined at resolutions of 2.19 Å for the native enzyme (PsyArAT) and 2.76 Å for its complex with aspartic acid (PsyArAT/D). Both types of crystals grew in the monoclinic space group P21 under slightly different crystallization conditions. The PsyArAT crystals contained a dimer (90 kDa) in the asymmetric unit, which corresponds to the active form of this enzyme, whereas the crystals of the PsyArAT/D complex included four dimers showing different stages of the transamination reaction.

PubMed: 25760611
DOI: 10.1107/S1399004714028016

実験手法

X-RAY DIFFRACTION (2.19 Å)