Dopa oxidase activity in human hair bulbs measured by high-performance liquid chromatography.
Dopa oxidase activity in human hair bulbs measured by high-performance liquid chromatography.
复制标题
通过高效液相色谱法测量人毛球中的多巴氧化酶活性。
DOI：
10.1111/1523-1747.ep12355192
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发表时间：
1986
期刊：
影响因子：
--
通讯作者：
King,RA
中科院分区：
文献类型：
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作者：
Townsend,DW;Olds,DP;King,RA
本文建立了一种测定人毛囊酪氨酸酶多巴氧化酶（DO）活性的方法，并将该方法的结果与棕发、黑发、金发和红发受试者的毛囊酪氨酸酶酪氨酸羟化酶（TH）活性进行了比较。该方法利用了半胱氨酸对多巴醌的快速捕获，随后形成半胱氨酸基多巴，可通过高效液相色谱法测定。反应产物中检测到5- s -半胱氨酸多巴（5SCD）和2- s -半胱氨酸多巴（2SCD）。5SCD的形成与整个发色范围内TH活性和酶活性相关，而2SCD的形成似乎是非酶促的。2SCD的绝对数量对每个人来说都是恒定的，但与头发颜色或TH活性无关。5SCD的形成在60分钟内呈线性，而大部分2SCD在数秒内形成，不随时间变化。没有TH活性的白色毛球形成2SCD，而不是5SCD。我们得出结论，用这种方法可以定量测定人毛球中的酪氨酸酶活性，TH和DO是酪氨酸酶在广泛的发色和酶活性范围内的协调功能。
A method for measuring the dopa oxidase (DO) activity of human hairbulb tyrosinase has been developed and the results of this method have been compared with the tyrosine hydroxylase (TH) activity of hairbulb tyrosinase for brown-, black-, blond-, and red-haired subjects. The method takes advantage of the rapid trapping of dopaquinone by cysteine with the subsequent formation of cysteinyldopas which can be measured by high-performance liquid chromatography. 5-S-Cysteinyldopa (5SCD) and 2-S-cysteinyldopa (2SCD) were detected in the reaction products. Formation of 5SCD correlated with the TH activity over the full range of hair colors and enzyme activity, while 2SCD appeared to be formed nonenzymatically. The absolute amount of 2SCD was constant for each individual but did not correlate with hair color or TH activity. The formation of 5SCD was linear for 60 min while most of the 2SCD was formed within seconds and did not change with time. White hairbulbs which demonstrated no TH activity formed 2SCD, but not 5SCD. We conclude that tyrosinase activity can be quantitated in human hairbulbs by this method, and that TH and DO are coordinate functions of tyrosinase over a broad range of hair color and enzyme activity.