Structure of the complex of leech-derived tryptase inhibitor (LDTI) with trypsin and modeling of the LDTI-tryptase system.
Di Marco, S., Priestle, J.P.(1997) Structure 5: 1465-1474
- PubMed: 9384562 
- DOI: https://doi.org/10.1016/s0969-2126(97)00296-7
- Primary Citation of Related Structures:  
1AN1 - PubMed Abstract: 
Tryptase is a trypsin-like serine proteinase stored in the cytoplasmic granules of mast cells, which has been implicated in a number of mast cell related disorders such as asthma and rheumatoid arthritis. Unlike almost all other serine proteinases, tryptase is fully active in plasma and in the extracellular space, as there are no known natural inhibitors of tryptase in humans. Leech-derived tryptase inhibitor (LDTI), a protein of 46 amino acids, is the first molecule found to bind tightly to and specifically inhibit human tryptase in the nanomolar range. LDTI also inhibits trypsin and chymotrypsin with similar affinities. The structure of LDTI in complex with an inhibited proteinase could be used as a template for the development of low molecular weight tryptase inhibitors.
Organizational Affiliation: 
Istituto di Ricerche di Biologia Molecolare "P. Angeletti" (IRBM), Via Pontina Km 30,600, 00040 Pomezia, Rome, Italy.