3-mercaptolactate

3-mer·cap·to·lac·tate

(mer-kap'tō-lak'tāt),
A product of cysteine catabolism; formed by the action of lactate dehydrogenase on 3-mercaptopyruvate that was, in turn, formed by transamination of cysteine; present in normal human urine as a mixed disulfide with cysteine; elevated in the urine in people with mercaptolactate-cysteine disulfiduria.