Bunyatyan Institute of Biochemistry, National Academy of Sciences of the Republic of Armenia, Yerevan, Republic of Armenia.
Biochemistry (Mosc). 2012 Jan;77(1):92-7. doi: 10.1134/S0006297912010117.
In this study we have investigated the effect of reactive oxygen species produced by some chemicals in aqueous solutions on activity of adenosine deaminase 2 (ADA2) purified from human blood plasma. An activating effect on ADA2 was observed in vitro with sodium nitroprusside (SNP), the source of NO (nitrosonium ions NO(-) in aqueous solutions). Not SH-groups of cysteine but other amino acid residues sensitive to NO were responsible for ADA2 activation. The SNP-derived activation was more pronounced when purified ADA2 was preincubated with heparin and different proteins as an experimental model of the protein environment in vivo. The most effective was heparin, which is known for its ability to regulate enzyme and protein functions in extracellular matrix. We conclude that ADA2 is a protein with flexible conformation that is affected by the protein environment, and it changes its activity under oxidative (nitrosative) stress.
在这项研究中，我们研究了一些在水溶液中产生的活性氧物质对从人血浆中纯化的腺苷脱氨酶 2（ADA2）活性的影响。我们在体外观察到硝普酸钠（SNP）对 ADA2 的激活作用，SNP 是 NO（硝酰阳离子 NO(-)在水溶液中的来源）的来源。对 ADA2 起激活作用的不是半胱氨酸的 SH 基团，而是对 NO 敏感的其他氨基酸残基。当用肝素和不同的蛋白质作为体内蛋白质环境的实验模型预先孵育纯化的 ADA2 时，SNP 衍生的激活作用更为明显。最有效的是肝素，肝素以其调节细胞外基质中酶和蛋白质功能的能力而闻名。我们得出结论，ADA2 是一种构象灵活的蛋白质，受蛋白质环境的影响，并在氧化（硝化）应激下改变其活性。
