– Low Molecular Weight Phosphotyrosine Protein Phosphatase (LMW-PTP) is a member of the low molecular weight phosphotyrosine protein phosphatase family. LMW-PTP serves as an acid phosphatase and a protein tyrosine phosphatase (PTPase) by hydrolyzing protein tyrosine phosphate to protein tyrosine and orthophosphate. LMW-PTP can be detected in all human tissues, including adipocytes. LMW-PTP is a cytosolic enzyme that regulate cell proliferation and growth of leiomyomas during dephosphorylation of the PDGF receptor. In addition, LMW-PTP plays an important role in the regulation of physiological functions, such as stress resistance and synthesis of the polysaccharide capsule.