[{"from": "human", "value": "Could you give me a brief overview of this molecule? [C][Branch1][#Branch2][C@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1][S][S][C][C@H1][Branch1][=Branch1][C][=Branch1][C][=O][O-1][NH3+1]"}, {"from": "gpt", "value": "The molecule is a cysteine zwitterion derived from D-cysteine by transfer of a proton from each of the carboxy groups to the amino groups. It is an enantiomer of a L-cystine zwitterion. It is a tautomer of a D-cystine."}]