1.D.18 The Pore-forming Guanosine-Bile Acid Conjugate (GBC) Family
A ditopic guanosine-lithocholic acid conjugate forms discrete channels in planar phospholipid membranes. These pores are large, with nanoSiemen conductance levels, and stable, with 'open' times of seconds, distinguishing them from most synthetic channels, which typically conduct in the picosiemens range with millisecond lifetimes. Ma et al. (2008) propose that these large pores are due to the formation of G4-quartet superstructures within the membrane.
The reaction catalyzed by GBC is:
small molecules (in) → small molecules (out)