Target Enzymes for Cystatins

All human cystatins are assumed to have major biological roles as inhibitors of one or more target proteases of human and/or nonhuman origin. Identification of target proteases of biomedical relevance is, however, difficult. Only few examples of clear-cut identifications of target proteases for inhibitors are known, and these identifications usually rely on experiments by Nature and not by Man. Two examples are the identifications of granulocyte elastase as a target enzyme 

Synonyms cystatin A (R7) Acid cysteine proteinase inhibitor, epidermal SH-proteinase inhibitor, Stefin A cystatin B (R6) neutral cysteine proteinase inhibitor, Stefin B cystatin C See Section 8 in main text cystatin E cystatin M (S10) cystatin F leukocystatin (H2) cystatins S, SA, and SN (12) salivary cysteine proteinase inhibitor cystatin SN cystatin SU (Al) (Grubb, A., unpublished results) LMW- and HMW-kininogens (M9) a-cysteine proteinase inhibitor, a-thiol proteinase inhibitor. 

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