Fig. 1: B38-CAP, a bacteria-derived carboxypeptidase, is Angiotensin-converting enzyme 2 (ACE2)-like enzyme.
From: B38-CAP is a bacteria-derived ACE2-like enzyme that suppresses hypertension and cardiac dysfunction
a Crystal structures of BS-CAP and human ACE2 proteins. Inset: metal-coordinating residues (red) and substrate-binding residues (black) are shown. b Phylogenetic tree of ACE2 and bacterial ACE2-like carboxypeptidases. c SDS-PAGE analysis of recombinant proteins of BS-CAP, BA-CAP, and B38-CAP. d Dependence of ACE2-like proteolytic activity of BS-CAP, BA-CAP, and B38-CAP on anion concentration. ACE2 activity was measured with hydrolysis rate of the fluorogenic ACE2 substrate Nma-His-Pro-Lys(Dnp). e–h HPLC analysis of B38-CAP-treated angiotensin peptides. Ang II (e), Ang 1–9 (f), Ang 1–7 (g), or Ang I (h) (5 nmol each) was incubated with vehicle, recombinant B38-CAP protein, or recombinant ACE2 protein (5 μg each) for 90 min, then subjected to HPLC analysis. i, j Kinetic analysis for hydrolysis of Ang I with B38-CAP. HPLC analysis of angiotensin peptides generated after incubating Ang I with B38-CAP (i, j, upper panel). Amino acids in the same samples were quantified with LC-MS system (j, lower panel). Experiments were repeated more than three times and representative chromatography charts are shown. j Values are means ± SEM. n = 3 independent experiments.
