HPLC-ESI-Q-TOF-MS鉴定重组人白细胞介素-11的一级结构

Identification of rhIL-11 by HPLC-ESI-Q-TOF-MS Spectrometry

用液质联用技术分析鉴定重组人白细胞介素-11(rhIL-11)的一级结构。利用电喷雾四极杆飞行时间质谱(ESI-Q-TOF-MS)测定rhIL-11的精确分子质量,采用高效液相-电喷雾四极杆飞行时间串联质谱技术(HPLC-ESI-Q-TOF-MS/MS)测定其胰蛋白酶酶切后肽段的部分氨基酸序列并结合数据库检索进行结构鉴定。rhIL-11的实测分子质量为19 047.38 u,与理论分子质量19 047.29 u相比非常接近。HPLC-ESI-Q-TOF-MS/MS测定m/z664.45、m/z609.40的肽段的部分氨基酸序列分别为Glu-Pro-Glu-Leu-Gly-Thr-Leu和Leu-Asp-Ser-Thr-Val-Leu。将这两段序列在MASCOT数据库检索,结果表明rhIL-11的结构正确。

Recombinant human interleukin- 11 （rhIL- 11 ） was identified by high-performance liquid chromatography and electrospray ionization quadrupole time-of-flight mass spectrometry （HPLC-ESI-Q-TOF-MS）. The molecular mass of rhIL-11 was measured by ESI-Q- TOF-MS. The trypsin digested peptides of rhIL-11 at 37℃ over night were measured and then two double charged peptides （m/z 664.45, 609.40） were selected to measure its amino acid sequence by HPLC-ESI-Q-TOF-MS/MS. Search database with the measured amino acid sequence to identify rhIL-11. The measured molecular mass ofrhIL-11 was 19 047.38 u and as well as the theoretical value is 19 047.29 u. The two peptides＇ sequences measured by HPLC-ESI-Q-TOF-MS/MS were Glu-Pro-Glu-Leu-Gly-Thr-Leu and Leu-Asp-Ser-Thr- Val-Leu, which was hIL-11 as a result searched in MASCOT database.