Salivary gland tissue kallikrein family and processing of growth factor precursors and proenzymes.

Four major enzymes of the tissue kallikrein family were purified from the mouse submandibular gland and characterized. The sequences indicated that they were mK1, mK9, mK13, and mK22. All four enzymes showed kinin-releasing activity, with mK1 exhibiting the highest activity. Like mK13, mK9 and mK22 also processed prorenin to give renin and/or arginyl renin, although their activities were less than that of mK13. The results suggest that tissue kallikrein family enzymes bearing higher kinin-releasing activity have lower prorenin-converting activity and vice versa. These enzymes may possibly have a physiological role in the tissue renin-angiotensin system.