Digestion of recombinant O-GlcNAcylated human tau with different enzymes - RAW data files - nLC-Q Exactive HF acquisition

O-GlcNAcylated recombinant human tau was digested with different enzymes, rendering 5 digestion conditions: trypsin only (1), asp-N only (2), glu-C only (3), trypsin followed by asp-N (4) and trypsin followed by glu-C (5). nLC-HRMS analysis was performed for the identification of tau O-GlcNAc sites. Data were acquired in data dependent MS2 (ddMS2) mode and for low abundant O-GlcNAc peptides also in parallel reaction monitoring (PRM) mode.

将经O-连接N-乙酰葡糖胺（O-GlcNAc）修饰的重组人tau蛋白采用不同酶进行酶解，共得到5种酶解条件：仅胰蛋白酶酶解（条件1）、仅天冬氨酸蛋白酶asp-N酶解（条件2）、仅谷氨酸蛋白酶Glu-C酶解（条件3）、先经胰蛋白酶酶解再经asp-N酶解（条件4）以及先经胰蛋白酶酶解再经Glu-C酶解（条件5）。采用纳流液相色谱-高分辨质谱（nLC-HRMS）开展分析，以鉴定tau蛋白的O-GlcNAc修饰位点。数据采集采用数据依赖性二级质谱（ddMS2）模式；针对低丰度O-GlcNAc修饰肽段，额外采用平行反应监测（PRM）模式完成数据采集。