Meagher R B
Biochim Biophys Acta. 1977 Sep 27;494(1):33-47. doi: 10.1016/0005-2795(77)90132-5.
Muconolactone isomerase is shown to be resistant to proteolytic cleavage by trypsin. Cyanogen bromide cleavage at the methionine residues of the polypeptide is at least 95% complete. Six cyanogen bromide fragments are separated on DEAE-cellulose. One fragment is shown by amino acid analysis and carboxyl-terminal analysis to be an incomplete cleavage product. The five remaining fragments represent the entire polypeptide and have been ordered with respect to the entire muconolactone isomerase sequence. Approximately 50% of the polypeptide sequence could be determined from these fragments by the dansyl-Edman technique. The possible evolutionarily homologous origins of muconolactone isomerase and two analogous isomerases, carboxymuconolactone decarboxylase and sigma5-3-ketosteroid isomerase, are discussed.
已证明粘康酸内酯异构酶对胰蛋白酶的蛋白水解切割具有抗性。在多肽的甲硫氨酸残基处进行溴化氰切割至少95%完成。六个溴化氰片段在二乙氨基乙基纤维素上分离。通过氨基酸分析和羧基末端分析表明，其中一个片段是不完全切割产物。其余五个片段代表整个多肽，并且已根据整个粘康酸内酯异构酶序列进行了排序。通过丹磺酰-埃德曼技术可以从这些片段中确定约50%的多肽序列。本文还讨论了粘康酸内酯异构酶与另外两种类似异构酶，即羧基粘康酸内酯脱羧酶和sigma5-3-酮类固醇异构酶可能的进化同源起源。
