Cytochrome oxidase and proton translocation

1. 为了为建立激光闪光光解技术测量组织氧浓度系统收集基础数据，构建了快速扫描分光光度计、双闪分光光度计和时间分辨吸收分光光度计。快速扫描和双闪设备都是世界上性能最高的设备；前者可记录200 nm范围内512个连续的吸收和反射光谱，最大时间分辨率为1ms，后者的时间分辨率为1mus。这些仪器已广泛应用于相关领域的各个领域。酵母黄血红蛋白作为氧传感器的功能作用的发现是一个显著的成就。利用快速扫描装置结合光纤制成的光学探针，对肉中肌红蛋白的氧化过程进行了光谱跟踪。通过解剖肉块，将其内部暴露在空气中的氧气中，切割表面的颜色从深棕色变为鲜红色。光谱变化清楚地表明氧肌红蛋白的形成，其特征是在582和540 nm处有一个生长峰，在591 nm处有一个等吸点。在582 nm处和591 nm处的吸光度变化总是双相的。利用所构建的所有装置研究了含氧血红蛋白在不同氧浓度下的光解和重组过程，并收集了相关的动力学数据。这些动力学参数与氧浓度相关，并建立了测定溶液中氧浓度的方法。根据这些数据，揭示了组织氧浓度测定中涉及的各种问题。

1. In order to collect fundamental data for establishing the system to measure the concentration of tissue oxygen by utilizing a laser flash photolysis technique, a rapid-scan spectrophotometer, double-flash spectrophotometer and a time-resolved absorption spectrophotometer were constructed. Both rapid-scan and double-flash apparatuses are of the highest performance ever built in the world; the former allows to record 512 consecutive absorption and reflectance spectra of a 200-nm span at the maximum time resolution of 1 ms, and the latter has a time resolution of 1mus. These apparatuses have been used extensively in wide areas of related fields. One of remarkable achievements is the finding of the functional role of yeast flavohemoglobin as an oxygen sensor.2. Oxygenation process of myoglobin contained in meat was followed spectrally by using the rapid-scan apparatus in combination with an optical probe made of optical fibers. Upon exposure of the interior to air oxygen by dissecting a meat lump, a color of the cut surface changes from dark brown to bright red. The spectral changes clearly indicate the formation of oxymyoglobin which is characterized by a growth of peaks at 582 and 540 nm with an isosbestic point at 591 nm. The absorbance changes followed at 582 nm against 591 nm as reference are invariably biphasic.3. The photodissociation of oxyhemoglobin and its recombination process have been studied by utilizing all of the apparatuses constructed and relevant kinetic data were collected at varying oxygen concentrations. These kinetic parameters are correlated with the oxygen concentration and the procedure to measure the oxygen concentration in solution has been established. Based on these data a variety of problems involved in the determination of tissue oxygen concentrations are revealed.