抗酒石酸酸性磷酸酶5B在人血清中与α2-巨球蛋白和钙形成复合物循环。
Tartrate-resistant acid phosphatase 5B circulates in human serum in complex with alpha2-macroglobulin and calcium.
作者信息
Ylipahkala Hannele, Halleen Jussi M, Kaija Helena, Vihko Pirkko, Väänänen H Kalervo
机构信息
Department of Anatomy, Institute of Biomedicine, University of Turku, 20520 Turku, Finland.
出版信息
Biochem Biophys Res Commun. 2003 Aug 22;308(2):320-4. doi: 10.1016/s0006-291x(03)01390-1.
Tartrate-resistant acid phosphatase (TRACP) is an enzyme with unknown biological function. In addition to its acid phosphatase activity, TRACP is capable of generating reactive oxygen species (ROS) at neutral pH. Two forms of TRACP circulate in human serum, macrophage-derived TRACP 5a and osteoclast-derived TRACP 5b. Here we have studied the circulating forms of the osteoclast-derived TRACP 5b in rat and human serum. In human serum, TRACP 5b circulates in a large complex that contained alpha2M and calcium. On the contrary, rat serum TRACP 5b circulates as a free molecule. Formation of the TRACP 5b complex in vitro decreased significantly the ROS generating activity of TRACP 5b without affecting its phosphatase activity. These results suggest that the complex formation may be necessary to eliminate the formation of the harmful ROS in the neutral pH of serum.
抗酒石酸酸性磷酸酶（TRACP）是一种生物学功能未知的酶。除了具有酸性磷酸酶活性外，TRACP还能够在中性pH条件下产生活性氧（ROS）。两种形式的TRACP在人血清中循环，即巨噬细胞衍生的TRACP 5a和破骨细胞衍生的TRACP 5b。在此，我们研究了大鼠和人血清中破骨细胞衍生的TRACP 5b的循环形式。在人血清中，TRACP 5b以包含α2M和钙的大复合物形式循环。相反，大鼠血清中的TRACP 5b以游离分子形式循环。体外形成TRACP 5b复合物可显著降低TRACP 5b的ROS生成活性，而不影响其磷酸酶活性。这些结果表明，复合物的形成可能是消除血清中性pH条件下有害ROS形成所必需的。
Zotero 插件