Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Moto-oka, Fukuoka 819-0395, Japan.
Biochem Biophys Res Commun. 2011 Jul 15;410(4):829-33. doi: 10.1016/j.bbrc.2011.06.073. Epub 2011 Jun 15.
Post-translational internal protein labeling was explored through the insertion of a 13-mer peptidyl loop specifically recognized by microbial transglutaminase (MTG). The peptidyl loop included one lysine residue (abbreviated as the K-loop), and was designed and inserted into two different regions of the protein bacterial alkaline phosphatase (BAP). MTG-mediated selective labeling of a lysine residue in the K-loop was achieved with a functional Gln-donor substrate. Internal protein labeling in the vicinity of the active site of BAP (residues 91-93) markedly decreased the activity of the enzyme. Conversely, insertion of the K-loop at a site distal from the active site (residues 219-221) afforded site-specific and covalent internal protein labeling without impairing the activity of the enzyme.
通过插入一段被微生物转谷氨酰胺酶（MTG）特异性识别的 13 肽环，探索了翻译后内部蛋白质标记。该肽环包含一个赖氨酸残基（简称 K 环），并被设计和插入到蛋白质细菌碱性磷酸酶（BAP）的两个不同区域。MTG 介导的 K 环中赖氨酸残基的选择性标记是通过功能性 Gln-供体底物实现的。BAP 活性位点附近的内部蛋白质标记（残基 91-93）显著降低了酶的活性。相反，将 K 环插入远离活性位点的位置（残基 219-221）可进行位点特异性和共价内部蛋白质标记，而不会损害酶的活性。
