RESIDUE B3A 16 CONECT CG 4 CA HG1 HG2 HG3 CONECT CA 4 CG N CB HA CONECT N 3 CA H H2 CONECT CB 4 CA C HB1 HB2 CONECT C 3 CB O OXT CONECT O 1 C CONECT OXT 2 C HXT CONECT HG1 1 CG CONECT HG2 1 CG CONECT HG3 1 CG CONECT HA 1 CA CONECT H 1 N CONECT H2 1 N CONECT HB1 1 CB CONECT HB2 1 CB CONECT HXT 1 OXT END HET B3A 16 HETNAM B3A (3S)-3-AMINOBUTANOIC ACID FORMUL B3A C4 H9 N O2