Tanaka S, Mohri N, Kihara H, Ohno M
J Biochem. 1985 May;97(5):1377-84. doi: 10.1093/oxfordjournals.jbchem.a135191.
Selective separation of tryptophan-containing peptides has been attempted using 2-nitro-4-carboxyphenylsulfenyl chloride (NCps)-C1 as a reagent for hydrophobic modification of tryptophan. S-Carboxymethylated proteins were modified with NCps-C1 in 70% acetic acid and digested with TPCK-trypsin, and the digests were fractionated, directly or after partial fractionation on a Sephadex G-25 column, by high performance liquid chromatography using a reverse phase column. The tryptophan-containing peptides from the tryptic digests of S-carboxymethylated hen-egg white lysozyme and Trimeresurus flavoviridis phospholipase A2 were thus selectively separated and the amino acid sequences were determined, showing the validity of the method. The phenylthiohydantoin derivative of 2-(2'-nitro-4'-carboxyphenylthio)-L-tryptophan was synthesized and its spectroscopic and chromatographic properties determined, enabling us to identify the derivative on Edman sequencing.
已尝试使用2-硝基-4-羧基苯硫酰氯（NCps）-C1作为色氨酸疏水修饰试剂来选择性分离含色氨酸的肽段。将S-羧甲基化蛋白在70%乙酸中用NCps-C1进行修饰，然后用TPCK-胰蛋白酶消化，消化产物直接或在Sephadex G-25柱上进行部分分级分离后，通过使用反相柱的高效液相色谱进行分级分离。通过这种方式，选择性地分离了S-羧甲基化鸡蛋清溶菌酶和竹叶青磷脂酶A2的胰蛋白酶消化产物中的含色氨酸肽段，并测定了其氨基酸序列，证明了该方法的有效性。合成了2-(2'-硝基-4'-羧基苯硫基)-L-色氨酸的苯硫代乙内酰脲衍生物，并测定了其光谱和色谱性质，这使我们能够在埃德曼测序中鉴定该衍生物。
