Figure 6. Pore assembly process.

(a) The dominating assembly process of maculatin 1.1 is a C-terminal-first surface insertion (surface scavenging) catalysed by existing TM helices, which facilitates translocation of the polar side chains. (b) In addition, dimers can also form by direct TM–TM oligomerization. (c) Similarly, tetramers usually form from a TM trimer via surface recruitment. (d) Alternatively, assembly via TM oligomerization requires the joining TM peptide to first rotate to point its polar interface towards the existing trimer. (e) In rare cases, an association of two antiparallel dimers can occur. The final tetramer is the same in all three cases. (f) Hexamer and (g) octamer. Higher-order oligomers assemble solely via surface peptide scavenging (recruited peptide shown in red).