Reaction Mechanism of Heme Oxygenase

详细研究了血红素加氧酶对血红素的脱脂作用，特别是其限速开环步骤。光谱分析揭示了铁基物种作为开环中间体的形成。通过对中间酶复合体的结晶学研究，结合理论计算，最终解释了限速反应。我们还研究了一种新的血红素裂解反应，以阐明其机制，并成功地从培养的哺乳动物细胞中检测到新的血红素分解代谢产物。

Enzymatic heme degaradation by heme oxygenase, especially its rate-limiting ring opening step, have been studied in detail. Spectroscopic analysis reveals the formation of a ferryl species as a ring opening intermediate. Crystallographic study on an intermediate-enzyme complex combined with theoritical calculations finally elucidate the rate-limiting reaction. We also examined a novel heme cleavage reaction to clarify its mechanism and the new heme catabolites were succesufully detected from cultured mammalian cells.