Lonsdale-Eccles J D, Lynley A M, Dale B A
Biochem J. 1981 Sep 1;197(3):591-7. doi: 10.1042/bj1970591.
A two-dimensional electrophoretic procedure employing CNBr has been devised for the analysis of proteins in sodium dodecyl sulphate/polyacrylamide gels. The technique allows the detection of an unusual class of epidermal proteins that lack methionine. The proteins have been identified by this method in newborn mouse, rat, and rabbit, because they are stable in the presence of CNBr and consequently lie on a diagonal. Adult human epidermis also contains CNBr-stable proteins, but in lesser amounts than in the newborn rabbit or newborn rodents. The methionine-containing proteins (i.e., the keratins) are degraded by CNBr into a series of unique and characteristics peptides which lie below the diagonal. Inter- and intra-species similarities and differences exist between the individual keratins, depending on the number and distribution of their methionine residues. The peptide-map patterns for the rodent and lagomorph proteins are more similar to each other than to that for the human proteins. The maps for rat and rabbit skin proteins are the most similar. We conclude that the epidermal keratins are a closely related, yet individually distinct, group of proteins that are found in conjunction with a class of proteins that lack methionine. The latter proteins are related to the histidine-rich basic protein, an epidermal structural protein that aggregates with keratin filaments.
已设计出一种采用溴化氰的二维电泳方法，用于分析十二烷基硫酸钠/聚丙烯酰胺凝胶中的蛋白质。该技术可检测出一类不含蛋氨酸的特殊表皮蛋白质。通过这种方法已在新生小鼠、大鼠和兔子中鉴定出这些蛋白质，因为它们在溴化氰存在下稳定，因此位于对角线上。成人表皮也含有溴化氰稳定的蛋白质，但含量低于新生兔子或新生啮齿动物。含蛋氨酸的蛋白质（即角蛋白）被溴化氰降解为一系列独特的特征性肽段，这些肽段位于对角线下方。不同物种间以及同一物种内的角蛋白存在相似性和差异，这取决于它们蛋氨酸残基的数量和分布。啮齿动物和兔形目动物蛋白质的肽图模式彼此之间比与人类蛋白质的更相似。大鼠和兔子皮肤蛋白质的图谱最为相似。我们得出结论，表皮角蛋白是一组密切相关但又各自不同的蛋白质，它们与一类不含蛋氨酸的蛋白质共同存在。后一类蛋白质与富含组氨酸的碱性蛋白质有关，后者是一种与角蛋白丝聚集的表皮结构蛋白。
