|Statement||by Diane Tessarolo.|
|The Physical Object|
|Pagination||iv, 28 l. :|
|Number of Pages||28|
Carboxypeptidase activity was determined by a high‐performance liquid chromatography (HPLC)‐assisted assay using the substrate hippuryl‐ l ‐arginine as described elsewhere [17, 18]. The samples were analyzed in the presence and absence of mg mL −1 PTCI The carboxypeptidase activities were measured with an HPLC-assisted assay using the substrate Hip-Arg as described elsewhere (12, 31). The procedure was as follows. For the chromatographic assay, 10 [micro]L of enzyme solution was added to 40 [micro]L of substrate solution (30 mmol/L Hip-Arg, 50 mmol/L HEPES, pH ).+of. To date, several assays for procarboxypeptidase U (proCPU) determination exist, all having their own inherent disadvantages and advantages. A drawback Carboxypeptidase U (CPU, TAFIa, EC ) 1 belongs to the group of basic metallocarboxypeptidases, that is, enzymes that use Zn 2+ at their catalytic site to cleave the basic amino acids lysine and arginine from the C terminus of a variety of peptides and was first described by Hendriks and co-workers in ,.During the following years, CPU was identified as a
The CPU activities measured using this kinetic assay were in the range of % of those determined with our HPLC-assisted reference assay, and the obtained K(m) and k(cat) values for hippuryl-l-arginine and bradykinin were in good accordance with those described in the :// The CPU activities measured using this kinetic assay were in the range of 97–% of those determined with our HPLC-assisted reference assay, and the obtained K m and k cat values for hippuryl-l-arginine and bradykinin were in good accordance with those described in the literature. As expected, no arginine cleaving was seen using dipeptides By Ian Fleming - the book also incorporates updated discussions of many of the fundamental components of hplc systems and practical issues associated with the use of this analytical method this edition includes new or expanded treatments of sample preparation computer assisted method A carboxypeptidase in human serum different from carboxypeptidase N J. Clin. Chera. Clin. Biochem. Vol. 27, , pp. assisted assay s described elsewhere (26), with the following sing the HPLC-assisted assay (26). Preincubations were performed s follows:?sequence=1.
To show the reliability and repeatability of this assay, within-run (n = 20) and between-run (n = 15) variation was determined using a serum sample with a high CPN activity ( U/L) and a low CPN activity ( U/L). The kinetic assay was correlated with the HPLC-assisted assay using serum samples from healthy volunteers. HPLC measurement of angiotensin-converting enzyme plastic tubes containing 50 pL serum and 50 pL sodium chloride buffer solution (1 mol/L chloride in mol/L Tris phosphate buffer pH ). The final concentrations in the assay were 10 mmol/L FAPGG and mmoVL chloride. The tubes were vortexed, incubated for 15 min at 37 "C Due to the marked instability of this novel enzyme, they named it carboxypeptidase U (CPU, where ‘U’ indicates unstable) (Hendriks et al., a, b, ). CPU was characterized as a carboxypeptidase B-like entity able to cleave off basic C-terminal amino acids arginine and :// The CPU activities measured using this kinetic assay were in the range of % of those determined with our HPLC-assisted reference assay, and the obtained K(m) and k(cat) values for hippuryl-l