Fig. 6. An evaluation of the potential of stretches of amino acids in the VDAC sequences from human (HVDAC1), S. cerevisiae (YVDAC1), and N. crassa to form b strands lining the walls of a water-filled pore. The hydropathy values (Kyte and Doolittle) of each group of 10 amino acids was summed in such a way that every other value was multiplied by -1. The absolute values of these sums is plotted versus the number, of the first amino-acid in the group, from the N terminus. Large values (peaks) indicate a good alternating polar/non-polar pattern expected for a transmembrane b strand separating a polar from a non-polar environment.