Fig. 4

We constructed the above CPS1 models using the 6w2j.1.A human homology template in Swiss-Model software, respectively. The red marker in Figure A and the green marker in Figure C represent the 382 Pro position, the red marker in Figure B and the green marker in Figure D represent the 382 Leu position, the purple area in Figure D represents the amino acids and their functional residues near the missense mutation site, and the yellow areas in Figure C and Figure D represent the hydrogen bonding of amino acids to other sites. The mutation at the Pro position disrupts the primary and secondary structure of the original protein, and the amino acid loop at this position is ruptured, while the hydrogen bonding of the amino acid at this position to other amino acids is not significantly altered