THTPA, also known as THTP or THTPASE, is a member of the THTPase family. This protein is localized to the cytoplasm and expressed at low levels in a variety of tissues, including testis, uterus, prostate, bladder, lung and kidney. THTPA is a hydrolase that catalyzes the H2O-dependent hydrolysis of thiamine triphosphate (THTP) to thiamine diphosphate (THDP), the major form of thiamine within the cell. THTPA exists as a monomer and functions at an optimal pH of 8.5. Recombinant human THTPA protein, fused to His-tag at N-terminus, was expressed in E.coli and purified by using conventional chromatography techniques.