Human Lung Tryptase. Purification and Characterization
Document Type
Article
Publication Date
1-1-1984
Description
Human lung tryptase, a mast cell-derived trypsin-like serine protease, has been isolated from whole human lung tissue obtained at autopsy. Increased yields from this purification process have allowed extensive characterization of the enzyme. One of the critical steps in the purification scheme is the use of a linear heparin gradient to elute active material from cellulose phosphate. Gel filtration studies in 1.0 M NaCl yielded an apparent M(r) = 135,000, and subsequent electrophoresis on sodium dodecyl sulfate-polyacrylamide gels demonstrated the presence of two active species with apparent M(r) = 30,900 and 31,600. Enzymatic activity was sensitive to NaCl concentrations above 0.05 M and was only 50% in 0.15 M NaCl, decreasing to 18% in 0.6 M NaCl. The effects of synthetic and natural inhibitors have also been studied, confirming the enzyme's trypsin-like characteristics and demonstrating that naturally occurring serum inhibitors are incapable of diminishing its activity. A complete amino acid analysis showed a high tryptophan content. Lastly, antisera to human lung tryptase have been generated, and the immunological identity of active fractions has been investigated as well as the localization of the enzyme to the mast cell granule by immunohistochemical staining.
Citation Information
Smith, T. J.; Hougland, Margaret W.; and Johnson, D. A.. 1984. Human Lung Tryptase. Purification and Characterization. Journal of Biological Chemistry. Vol.259(17). 11046-11051. https://doi.org/10.1016/S0021-9258(18)90620-4 PMID: 6432791 ISSN: 0021-9258