Top-down MS picking up speed

摘要

Although some prefer to focus on the forest,others like to start with the trees.The two MS-based approaches to proteomics-bottom-up,in which the proteins of interest are first digested into peptides and then separated before MS analysis,and top-down,which first detects the intact proteins and then forms protein pieces via gas-phase fragmentation-are no different.Usually,the two approaches provide complementary information.