1 research outputs found
Probing the Lysine Proximal Microenvironments within Membrane Protein Complexes by Active Dimethyl Labeling and Mass Spectrometry
Positively charged
lysines are crucial to maintaining the native
structures of proteins and protein complexes by forming hydrogen bonds
and electrostatic interactions with their proximal amino acid residues.
However, it is still a challenge to develop an efficient method for
probing the active proximal microenvironments of lysines without changing
their biochemical/physical properties. Herein, we developed an active
covalent labeling strategy combined with mass spectrometry to systematically
probe the lysine proximal microenvironments within membrane protein
complexes (∼700 kDa) with high throughput. Our labeling strategy
has the advantages of high labeling efficiency and stability, preservation
of the active charge states, as well as biological activity of the
labeled proteins. In total, 121 lysines with different labeling levels
were obtained for the photosystem II complexes from cyanobacteria,
red algae, and spinach and provided important insights for understanding
the conserved and nonconserved local structures of PSII complexes
among evolutionarily divergent species that perform photosynthesis