RESIDUE 52A 22 CONECT N 3 CA HN1 HN2 CONECT CA 4 N C CB1 CB2 CONECT C 3 CA O OXT CONECT O 1 C CONECT OXT 2 C HOXT CONECT CB1 4 CA CG1 HB11 HB12 CONECT CB2 4 CA NG2 HB21 HB22 CONECT CG1 4 CB1 NG2 CD HG1 CONECT NG2 3 CB2 CG1 HNG2 CONECT CD 3 CG1 OE1 OE2 CONECT OE1 1 CD CONECT OE2 2 CD HOE2 CONECT HN1 1 N CONECT HN2 1 N CONECT HOXT 1 OXT CONECT HB11 1 CB1 CONECT HB12 1 CB1 CONECT HB21 1 CB2 CONECT HB22 1 CB2 CONECT HG1 1 CG1 CONECT HNG2 1 NG2 CONECT HOE2 1 OE2 END HET 52A 22 HETSYN 52A 2R,4R-APDC HETNAM 52A (2R,4R)-4-aminopyrrolidine-2,4-dicarboxylic acid FORMUL 52A C6 H10 N2 O4