Crystal packing.

<p><b>(A)</b> Orientation of P-gp molecules in the crystal lattice from which the 3G5U and 4M1M structural models were derived. The asymmetric unit contains two P-gp molecules (the NBDs highlighted in violet and magenta, respectively). <b>(B)</b> The crystal lattice representation of the 4KSB model, where the asymmetric unit contains a single P-gp molecule. Both crystal lattices belong to the P21 21 21 space group and the unit cell is represented with the blue wireframe.