Figure 5.

Schematic representation of the observed knotting mechanisms for MJ0366. The largely dominant mechanism is direct threading, when a straight, helically-arranged C-terminus threads an already formed native loop, locked by the non-local β-sheet. Occasionally, the knot can form via slipknotting. This happens when the loop is threaded by a backward-bent C-terminus. A further, though rare, knotting mechanism is mousetrapping, which arises when the loop region concertedly rotates and entraps the C-terminus. Adapted with permission from [38].