The protein in this puzzle is from Cucurbita maxima, a species which includes many types of pumpkins and squashes. The protein is a trypsin inhibitor, which blocks the enzyme trypsin. Trypsin breaks down proteins. Trypsin inhibitors in general can interfere with digestion of proteins, but the puzzle protein has a specific inhibitory effect on human blood coagulation factor beta-factor XIIa.
The puzzle protein has 44 segments with the sequence:
This sequence is found in this Protein Data Bank entries:
This puzzle does not have any ligands.
This puzzle has a single chain.
See players' solutions from previous visits this puzzle: