How the O2-dependent Mg-protoporphyrin monomethyl ester cyclase forms the fifth ring of chlorophylls

Data-files acquired by reverse phase liquid chromatography coupled online to electrospray-ionisation mass spectrometry (Q Exactive HF, Thermo Scientific).(1) 20200213_PJ_GC_MS1: full-scan MS, 500-700 m/z(2) 20200213_PJ_GC_PRM: product ion scans by parallel reaction monitoring for cyclase substrate MgPME, product DV PChlide a, and catalytic intermediates 131-hydroxy-MgPME and 131-keto-MgPME at m/z 598, 611, 614 and 612 respectively.Thermo RAW files are included in mzML format which is readable by open source applications such as SeeMS (http://proteowizard.sourceforge.net/download.html).通过反相液相色谱与电喷雾电离质谱联用（Q Exactive HF，赛默飞世尔科技）获取的数据文件。（1）20200213_PJ_GC_MS1：全扫描质谱，m/z 500-700；（2）20200213_PJ_GC_PRM：通过并行反应监测对环化酶底物MgPME、产物PChlide a以及催化中间体131-羟基-MgPME和131-酮基-MgPME分别在m/z 598、611、614和612处进行产物离子扫描。包含在mzML格式中的赛默飞世尔科技原始文件，可由开源应用程序如SeeMS（http://proteowizard.sourceforge.net/download.html）读取。