Fig. 4.

Storage properties of coiled-coil domains. COMPcc has been shown to store vitamin A (A) and vitamin D₃ (B). In both cases the elongated cargo is oriented such that its hyroxyl group can form an electrostatic interaction with the Gln⁵⁴ ring system. In contrast to vitamin A where only molecule is bound, COMPcc can store two vitamin D₃ molecules, one in each cavity. (C) The larger cavities in RHCC can store one molecule of cisplatin each. Whereas aliphatic, elongated cargos in COMPcc are diffusing via both N- and C-terminus into the hydrophobic channel, the ionic network in RHCC allows for a diffusion of cisplatin via the inter-helical interface.