1.B.8.1.17
Non-selective channel of the thylakoid membrane of 275 aas and one TMSs, CpTPOR (Kojima et al. 2018). The channels are large enough for permeation of small organic compounds (e.g. carbohydrates and amino acids with M_r < 1500). The pore has an estimated radius of ∼1.3 nm and exhibits a typical single-channel conductance of 1.8 nS in 1 m KCl with infrequent closing transitions. CpTPOR exhibits no obvious selectivity for anions and no voltage-dependent gating. It presumably enables rapid transfer of various metabolites between the lumen and stroma (Kojima et al. 2018).