Fig. 6: Characterization of the exterior KDL binding site.
From: Structural basis for lipid and copper regulation of the ABC transporter MsbA
a Deconvoluted mass spectrum of 0.3 μM MsbAR188A,K243A in the presence of 0.4 μM KDL. b Deconvoluted mass spectrum of 0.4 μM vanadate-trapped MsbAR188A,K243A with same concentration of KDL as in panel a. c KD values for KDL binding to the wild-type and mutant MsbA. d ATPase activity of MsbA, MsbAR188A,K243A, and MsbAR78A,K299A in the presence and absence of 5 μM lipid A (LA) (*p = 0.047; 0.011), KDL (**p = 0.008; 0.005, *p = 0.019), or Ra-LPS (LRa) (**p = 0.004; 0.009). A two-sided student’s t-test was used to test for statistical significance. e Alignment of different structures to a region of TM5, residue range from 230 to 250. The first four panels shown (from left to right) correspond to apo (this report), G907 bound (PDB 6BPL), and vanadate-trapped in an occluded (PDB 7BCW) or open (this report) MsbA structures. The rightmost panel is an overlay of all four structures. Reported are the mean and standard deviation (n=3, biological replicates). Source data are provided as a Source Data file.
