MODRES 2C5V ABA F  503  GLU  ALPHA-AMINOBUTYRIC ACID                            
MODRES 2C5V ABA H  503  GLU  ALPHA-AMINOBUTYRIC ACID                            
MODRES 2C5V PFF F  508  PHE  4-FLUORO-L-PHENYLANANINE                           
MODRES 2C5V PFF H  508  PHE  4-FLUORO-L-PHENYLANANINE