FIGURE 2.
Effect of a CTRC inhibitor on the re-synthesis of the Leu81–Glu82 peptide bond by human CTRC. The re-synthesis experiment was performed with S200A-trypsin (Tr) as described in “Materials and Methods,” in the absence or presence of 500 nm CTRC inhibitor C4. This is a phage-display selected variant of the Schistocerca gregaria proteinase inhibitor-2 (SGPI-2), which inhibits human CTRC with a Ki of 20 pm. See Ref. (16) for details. A, representative gels of two experiments are shown. B, densitometric quantitation of the intact trypsin band. Error bars were omitted for clarity; the error was within 5% of the mean.