Figure shows this count starting from a formed fusion pore without SMACs (cyan line) and for the same system but with 36 SMACs (12 extra-organelle and 24 intra-organelle). The time instant when the pore closes is indicated for both simulations as a step down in the C4 count. Although the closure event marginally reduces C4:water contacts, it is observed that the presence of SMACs reduce the amount of waters inside the bilayer (orange line). Molecular dynamics snapshots in panel 6a show representative splaying lipids (red molecules) and intra-organelle SMACs ascending inside the pore through the water channel (blue molecules). Nevertheless, we have observed a special case where one extraorganelle SMAC connects both bilayers (in a bridge-like way) which has the opposed effect. Under this particular configuration, a single extra-organelle SMAC mechanically pulls from both bilayers toward the centre of the inter-membrane space, disordering membrane molecules at the lipid-water interface and facilitating the infiltration of water molecules.