title: Nicotianamine is a novel angiotensin-converting enzyme 2 inhibitor in soybean.
abstract: Angiotensin-converting enzyme 2 (ACE2) is a carboxypeptidase which is highly homologous to angiotensin-converting enzyme (ACE). ACE2 produces vasodilator peptides angiotensin 1-7 from angiotensin II. In the present study, we synthesized various internally quenched fluorogenic (IQF) substrates (fluorophore-Xaa-Pro-quencher) based on the cleavage site of angiotensin II introducing N-terminal fluorophore N-methylanthranilic acid (Nma) and C-terminal quencher N(ε)-2,4- dinitrophenyl-lysine [Lys(Dnp)]. The synthesized mixed substrates "Nma-Xaa-Pro-Lys(Dnp)" were hydrolyzed by recombinant human (rh) ACE2. The amount of each product was determined by liquid chromatography mass spectrometry (LC-MS) with fluorescence detection and it was found that Nma-His-Pro-Lys(Dnp) is the most suitable substrate for rhACE2. The K(m), k(cat), and k(cat)/K(m) values of Nma-His-Pro-Lys(Dnp) on rhACE2 were determined to be 23.3 μM, 167 s(-1), and 7.17 μM(-1) s(-1), respectively. Using the rhACE2 and the newly developed IQF substrate, we found rhACE2 inhibitory activity in soybean and isolated the active compound soybean ACE2 inhibitor (ACE2iSB). The physicochemical data on the isolated ACE2iSB were identical to those of nicotianamine. ACE2iSB strongly inhibited rhACE2 activity with an IC50 value of 84 nM. This is the first demonstration of an ACE2 inhibitor from foodstuffs.
authors.affiliation: Akita Research Institute of Food and Brewing.
authors.forename: Saori
authors.initials: S
authors.lastname: Takahashi
authors.forename: Taku
authors.initials: T
authors.lastname: Yoshiya
authors.forename: Kumiko
authors.initials: K
authors.lastname: Yoshizawa-Kumagaye
authors.forename: Toshihiro
authors.initials: T
authors.lastname: Sugiyama
mesh_terms: D000085962:Angiotensin-Converting Enzyme 2; D000806:Angiotensin-Converting Enzyme Inhibitors / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D001383:Azetidinecarboxylic Acid / Q000031:analogs & derivatives* / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D006801:Humans; D020128:Inhibitory Concentration 50; D015394:Molecular Structure; D007703:Peptidyl-Dipeptidase A / Q000378:metabolism*; D010936:Plant Extracts / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D011994:Recombinant Proteins / Q000378:metabolism; D013025:Glycine max / Q000737:chemistry*
chemical_list: D000806:Angiotensin-Converting Enzyme Inhibitors; D010936:Plant Extracts; D011994:Recombinant Proteins; C082893:nicotianamine; D001383:Azetidinecarboxylic Acid; D007703:Peptidyl-Dipeptidase A; C000705307:ACE2 protein, human; D000085962:Angiotensin-Converting Enzyme 2