• 作者： 陳敏男;沈森燦;王松茂
• 作者服務機構： 國立清華大學化學系
• 中文摘要： 鹵離子對臺灣蝸牛血青素與氧結合作用之影響，用UV吸收光譜、螢光光譜及NMR方法探討。含氧血青素在345 nm有電荷轉移吸收帶，而不受KCl及KBr存在之影響，但在溶液pH 5.0時KF之添加卻降低345 nm吸光度且增強螢光產率。此現象可用中性HF分子在血青素活性部位取代過氧離子來說明。在pH 5.0 KF濃度0.3 M時HF與血青素以初反應速率0.038作用形成HF與血青素錯合物，其解離係數為0.22 M。在pH 9.0時氟離子以結合係數0.52結合於含氧血青素，而不影響其345 nm吸收帶與螢光產率。
• 英文摘要： The effect of potassium fluoride, chloride, and bromide on the oxygen binding of Achatina hemo-cyanin from Taiwan snail has been studied by ultraviolet spectrophotometric, fluorescence, and NMRmethods. The presence of KCl and KBr up to 0.8 M does not affect the binding of oxygen in oxyhemocy-anin. Addition of KF at pH 5.3 causes a decrease in absorbance at 345 nm and an enhancement of thefluorescence yield of oxyhemocyanin, which are ascribed to the displacement of peroxide from the activesite of hemocyanin by the neutral HF molecule. The apparent dissociation constant for the HF-hemocy-anin complex was evaluated to be 0.22 M, and the primary reaction occurred with observed rate constantsof 0.038 for 0.3 M, at pH 5.3. At pH 9.0 fluoride ion binds to oxyhemocyanin with the binding con-stant of 0.52 and does not affect the absorbance at 345 nm and the fluorescence yield.
• 中文關鍵字： hemocyanin; interaction; absorption spectral; NMR; fluorescence
• 英文關鍵字： --