SERPINB1 (NM_030666) Human Recombinant Protein

Snippet: in duplicate. Specificity of the ELISA was examined by substituting samples with 10 ng/mL of recombinant human serpinB1 with an N‐terminal polyhistidine tag (OriGene, Rockville, MD). Metabolic testing. Each participant underwent ... All 4 versions Cite SaveSaving

Snippet: Second, peptidase assays demonstrated that insect cell-derived untagged SerpinB1 from two independent preparations dose-dependently decreased activity of these proteases (shown for NE);however, the commercial proteins that are tagged at the N terminus (GeneCopoeia or OriGene) or C terminus (OriGene) only minimally inhibited peptidase activity of NE (Figure 5B). GeneCopoeia N-tagged SerpinB1 and OriGene C-tagged serpinB1 formed small amounts of complex, which was maximal with <0.1 or 0.3 molar equivalents NE, respectively, consistent with low inhibition in the peptidase assay;the OriGene C-tagged serpinB1 was also partially degraded (Figure 5C). For OriGene N-tagged serpinB1, no complex was detected on incubation with 0.3 molar equivalents of NE, and the recombinant serpin was completely degraded by NE;proteolytic degradation of the serpin by NE was confirmed by inactivating NE with DFP (diisopropyl fluorophosphate) (Amrein and Stossel, 1980) before use (Figure 5C)