Extended Data Figure 7. Conformation space of type I ABC exporters.

a-c, Conformation space of the EM structures from this study and previously published ABC tranporter structures is shown based on three parameters: the intracellular gate angle (IC angle), the extracellular gate angle (EC angle), and the distance between two nucleotide-binding domains (NBD distance). The EM structures, obtained in this study, are shown as blue circles, and previously published structures as orange triangles. The clustering of structures in three major conformations (IF, OF^open, and OF^occluded) is highlighted by dashed rectangles in a and b. The EM structures, obtained in this study, cover all main conformations. The new UR^asym conformations have closest resemblance to OF^occluded. The IC angle is defined as the angle between two vectors: vector 1 between the center of mass of the whole extracellular part of the TMD region and the center of mass of the intracellular parts of TM1^TmrA, TM2^TmrA, TM3^TmrA, TM6^TmrA, TM4^TmrB, and TM5^TmrB; and vector 2 between the center of mass of the whole extracellular part of the TMD region and the center of mass of the intracellular parts of TM1^TmrB, TM2^TmrB, TM3^TmrB, TM6^TmrB, TM4^TmrA, and TM5^TmrA. The EC angle is defined as the angle between two vectors: vector 3 between the centers of mass of the NBDs and the extracellular parts TM1^TrmA, TM2^TrmA, TM3^TrmB, TM4^TrmB, TM5^TrmB, and TM6^TrmB; and vector 4 between the center of mass of the NBDs and of the extracellular parts TM1^TmrB, TM2^TmrB, TM3^TmrA, TM4^TmrA, TM5^TmrA, and TM6^TmrA. The NBD distance is defined by the centers of mass of two NBDs (N-terminal loops and C-terminal helices were excluded). IF: IF conformation; O: OF^open conformation; C: OF^occluded conformation; Vi: TmrAB_ATP-Vi; EQ: TmrA^EQB. PDB IDs: PCAT: 4RY2 and 4S0F for the IF and OF^occluded conformation, respectively⁵¹; McjD: 4PL0¹⁶; Pgp: 6C0V⁵²; MsbA: 5TTP⁵³; PglK: 5C73⁵⁴; MRP: 6BHU⁵⁵; Sav: 2ONJ¹⁸; TmrAB: 5MKK¹²; TM287 (TM287/288): 4Q4A⁵⁶. d, Time-dependent IC angle in independent MD simulations of IF^wide and IF^narrow with ATP/ATP, ADP/ATP, and ADP/ADP in the canonical/non-canonical site, respectively.