Baden H P, Lee L D
J Invest Dermatol. 1978 Aug;71(2):148-51. doi: 10.1111/1523-1747.ep12546905.
The fibrous proteins of the malpighian layer of human epidermis (prekeratin) have been isolated with citrate buffer, pH 2.65, and shown to consist of 7 polypeptide chains varying in molecular weight from 45,000 daltons to 67,000. Some variation in the number and amount of the components was observed in prekeratin prepared from the epidermis of different individuals. The fibrous proteins of the stratum corneum were isolated with Tris buffer, pH 9.0, containing 6 M urea and 0.1 M mercapto-ethanol and were found to have a pattern similar to prekeratin but not identical to it. However, fibrous protein isolated from the superficial layers of the stratum showed a considerably different pattern indicating that there was post-translational modification of the protein in the late stages of keratinization. These data show that human keratin has the same heterogeneity which was observed previously in cow epidermis. This was further confirmed by studying the polypeptide chain content of prekeratin from a large number of lesions showing benign epidermal hyperplasia, where considerable variation in composition was observed.
人表皮马尔皮基层的纤维蛋白（前角蛋白）已用pH 2.65的柠檬酸盐缓冲液分离出来，结果显示其由7条多肽链组成，分子量在45,000道尔顿至67,000道尔顿之间。在从不同个体表皮制备的前角蛋白中，观察到了成分数量和含量的一些差异。角质层的纤维蛋白是用pH 9.0的Tris缓冲液分离出来的，该缓冲液含有6M尿素和0.1M巯基乙醇，结果发现其模式与前角蛋白相似但不完全相同。然而，从角质层表层分离出的纤维蛋白显示出明显不同的模式，这表明在角质化后期蛋白质发生了翻译后修饰。这些数据表明，人角蛋白具有与先前在牛表皮中观察到的相同的异质性。通过研究大量显示良性表皮增生的病变组织中前角蛋白的多肽链含量，进一步证实了这一点，在这些病变组织中观察到了组成上的显著差异。
