Fig. 3: Lipids modulate MsbA nucleotide interactions and populate distinct stoichiometries.

a Deconvoluted mass spectra of 0.5 µM MsbA mixed with 10 µM Mg²⁺ and 50 µM ATP. Data were acquired after mixing (top) and incubation for 30 min (bottom). The peaks corresponding to MsbA binding ATP and ADP are labeled in zoomed inset. b Deconvoluted mass spectra of 0.5 µM MsbA mixed with 10 µM Mg²⁺, 50 µM ATP and 3 µM TOCDL after mixing (top) and 30-min incubation (bottom). c Deconvoluted mass spectra of 0.5 µM MsbA mixed with 10 µM Mg²⁺, 50 µM ATP and 1 µM KDL after mixing (top) and 30-min incubation (bottom). The number of lipids and ATPs bound are labeled.