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Figure 1 ProBNP Processing

ProBNP is a 108-amino acid (aa) precursor protein which is cleaved by the endoprotease corin to form the bioactive 32 aa BNP peptide (referred to as BNP_1-32 or as proBNP_77-108) and the inert 76 aa N-terminal-proBNP peptide (proBNP_1-76). Each fragment undergoes further N-terminal dipeptidase digestion, as might proBNP itself. BNP = B-type natriuretic peptide.