Figure 1

Characterization of BmCatD gene and protein product. (A) Genomic structure of BmCatD gene revealed by PCR amplification from BmCatD cDNA. Numbers indicate the position in the genomic sequences. GenBank accession numbers are AY297160 (BmCatD cDNA) and DQ417605 (BmCatD genomic DNA). (B) N-linked glycosylation of recombinant BmCatD expressed in baculovirus-infected insect Sf9 cells. The recombinant AcNPV-infected Sf9 cells were treated with (+) or without (-) tunicamycin and the cell lysates were analyzed by Western blot analysis. (C) Optimum pH of recombinant BmCatD. The N-linked glycosylated (solid circle) and nonglycosylated (open circle) BmCatD polypeptides were purified from culture supernatants. The pH dependency of recombinant BmCatD activity on 2% hemoglobin was assayed directly at different pHs.