Figure 3.

Propofol binding site(s) on molecule leukocyte function–associated antigen-1 suggested by photolabeling experiment and docking calculation. Azi-propofol-m (azi-Pm) photolabeling experiments were performed twice as shown in Table 1. The sequence coverage was significantly better in experiment 1, and we used experiment 1 as a representative. Notably, the adducted residues by azi-Pm were located at the allosteric pocket underneath the C-terminal α 7 helix of the αL I domain. A and B, The docked propofol on the α I domain (protein data bank 1ZOO) is shown. Residues photolabeled by azi-Pm are shown in blue. The blowup of the docking site is shown in panel B. The metal ion–dependent adhesion site (MIDAS) is shown in the gold sphere. In propofol: red, oxygen; green, carbon. C, Amino acid residues of the α I domain. Sequenced residues by mass spectrometry in experiment 1 are underlined. Adducted residues by azi-Pm are shown in asterisk. Residues with 4 Å from docked propofol are in red.