4J6V

Crystal Structure of Tyrosinase from Bacillus megaterium N205D mutant

4J6V の概要

• エントリーDOI: 10.2210/pdb4j6v/pdb
• 関連するPDBエントリー: 3NM8 4J6T 4J6U
• 分子名称: Tyrosinase, COPPER (II) ION (3 entities in total)
• 機能のキーワード: type 3 copper proteins, oxidoreductase
• 由来する生物種: Bacillus megaterium
• タンパク質・核酸の鎖数: 2
• 化学式量合計: 70638.01

構造登録者

Kanteev, M.,Goldfeder, M.,Adir, N.,Fishman, A. (登録日: 2013-02-12, 公開日: 2013-12-25, 最終更新日: 2024-02-28)

主引用文献

Kanteev, M.,Goldfeder, M.,Chojnacki, M.,Adir, N.,Fishman, A.
The mechanism of copper uptake by tyrosinase from Bacillus megaterium.
J.Biol.Inorg.Chem., 18:895-903, 2013

PubMed Abstract: Tyrosinase belongs to the type 3 copper enzyme family, containing a dinuclear copper center, CuA and CuB. It is mainly responsible for melanin production in a wide range of organisms. Although copper ions are essential for the activity of tyrosinase, the mechanism of copper uptake is still unclear. We have recently determined the crystal structure of tyrosinase from Bacillus megaterium (TyrBm) and revealed that this enzyme has tighter binding of CuA in comparison with CuB. Investigating copper accumulation in TyrBm, we found that the presence of copper has a more significant effect on the diphenolase activity. By decreasing the concentration of copper, we increased the diphenolase to monophenolase activity ratio twofold. Using a rational design approach, we identified five variants having an impact on copper uptake. We have found that a major role of the highly conserved Asn205 residue is to stabilize the orientation of the His204 imidazole ring in the binding site, thereby promoting the correct coordination of CuB. Further investigation of these variants revealed that Phe197, Met61, and Met184, which are located at the entrance to the binding site, not only play a role in copper uptake, but are also important for enhancing the diphenolase activity. We propose a mechanism of copper accumulation by the enzyme as well as an approach to changing the selectivity of TyrBm towards L-dopa production.

PubMed: 24061559
DOI: 10.1007/s00775-013-1034-0

実験手法

X-RAY DIFFRACTION (1.9 Å)