Converts angiotensin I to angiotensin II by release of the terminal His-Leu, this results in an increase of the vasoconstrictor activity of angiotensin. Also able to inactivate bradykinin, a potent vasodilator. Has also a glycosidase activity which releases GPI-anchored proteins from the membrane by cleaving the mannose linkage in the GPI moiety.
The phosphorylation of the short C-terminal cytoplasmic domain of the somatic angiotensin-converting enzyme (ACE) is involved in the regulation of enzyme shedding. We determined whether the phosphorylation of the cytoplasmic domain of ACE (ACEct) on Ser1270 regulates the cleavage/secretion of the enzyme by affecting its association with other proteins. ACE was associated with beta-actin and the nonmuscle myosin heavy chain IIA (MYH9) in endothelial cells, as determined by coimmunoprecipitation experiments as well as an ACEct affinity column. The ACE-associated MYH9 immunoprecipitated from (32)P-labeled endothelial cells was basally phosphorylated and cell stimulation with ACE inhibitors, or with bradykinin, increased the phosphorylation of MYH9. Casein kinase 2 (CK2) but not protein kinase C phosphorylated MYH9 in vitro, CK2 coprecipitated with MYH9 from endothelial cells and the phosphorylation of MYH9 in intact cells paralleled the phosphorylation of ACE on Ser1270 by CK2. The CK2 inhibitor 5,6-dichloro-1-beta-d-ribofuranosylbenzimidazole attenuated the phosphorylation of ACE and MYH9, disrupted their association, and enhanced the cleavage/secretion of ACE from the plasma membrane. Cytochalasin D decreased the interaction between ACE and MYH9 and stimulated ACE shedding. Although MYH9 was still able to associate with residual amounts of a nonphosphorylatable S1270A ACE mutant, no ACE inhibitor-induced increase in MYH9 phosphorylation could be detected in S1270A-expressing cells. These data indicate that the interaction of ACE with MYH9 determines ACE shedding and is modulated by phosphorylation processes. Furthermore, because ACE inhibitors affect the phosphorylation of MYH9, the phosphorylation of this class II myosin might contribute to the phenomenon of ACE signaling in endothelial cells.
To investigate how angiotensin I-converting enzyme (ACE) inhibitors enhance the actions of bradykinin (BK) on B2 receptors independent of blocking BK inactivation, we expressed human somatic ACE and B2 receptors in CHO cells. Bradykinin and its ACE-resistant analog were the receptor agonists. B2 fused with green fluorescent protein (GFP) and ACE were coprecipitated with antisera to GFP or ACE shown in Western blots. Immunohistochemistry of fixed cells localized ACE by red color and B2-GFP by green. Yellow on plasma membranes of coexpressing cells also indicated enzyme-receptor complex formation. Using ACE-fused cyan fluorescent protein donor and B2-fused yellow fluorescent protein (YFP) acceptor, we registered fluorescence resonance energy transfer (FRET) by the enhanced fluorescence of donor on acceptor photobleaching, establishing close (within 10 nm) positions of B2 receptors and ACE. Bradykinin stimulation cointernalized ACE and B2 receptors. We expressed ACE fused to N terminus of B2 receptors, anchoring only receptors to plasma membranes. Here, in contrast to cells, where both ACE and B2 receptors are separately anchored, ACE inhibitors neither enhance activation of chimeric B2 nor resensitize desensitized B2 receptors. Heterodimer formation between ACE and B2 receptors can be a mechanism for ACE inhibitors to augment kinin activity at cellular level.
Angiotensin-converting enzyme (ACE) has a critical role in cardiovascular function by cleaving the carboxy terminal His-Leu dipeptide from angiotensin I to produce a potent vasopressor octapeptide, angiotensin II. Inhibitors of ACE are a first line of therapy for hypertension, heart failure, myocardial infarction and diabetic nephropathy. Notably, these inhibitors were developed without knowledge of the structure of human ACE, but were instead designed on the basis of an assumed mechanistic homology with carboxypeptidase A. Here we present the X-ray structure of human testicular ACE and its complex with one of the most widely used inhibitors, lisinopril (N2-[(S)-1-carboxy-3-phenylpropyl]-L-lysyl-L-proline; also known as Prinivil or Zestril), at 2.0 A resolution. Analysis of the three-dimensional structure of ACE shows that it bears little similarity to that of carboxypeptidase A, but instead resembles neurolysin and Pyrococcus furiosus carboxypeptidase--zinc metallopeptidases with no detectable sequence similarity to ACE. The structure provides an opportunity to design domain-selective ACE inhibitors that may exhibit new pharmacological profiles.
Interacting selectively and non-covalently with a drug, any naturally occurring or synthetic substance, other than a nutrient, that, when administered or applied to an organism, affects the structure or functioning of the organism; in particular, any such substance used in the diagnosis, prevention, or treatment of disease.
J. Biol. Chem. 267, 13398-13405 (1992)[PubMed:1320019]
The endothelial angiotensin I-converting enzyme (ACE; EC 3.4.15.1) has recently been shown to contain two large homologous domains (called here the N and C domains), each being a zinc-dependent dipeptidyl carboxypeptidase. To further characterize the two active sites of ACE, we have investigated their interaction with four competitive ACE inhibitors, which are all potent antihypertensive drugs. The binding of [3H] trandolaprilat to the two active sites was examined using the wild-type ACE and four ACE mutants each containing only one intact domain, the other domain being either deleted or inactivated by point mutation of the zinc-coordinating histidines. In contrast with all the previous studies, which suggested the presence of a single high affinity inhibitor binding site in ACE, the present study shows that both the N and C domains of ACE contain a high affinity inhibitor binding site (KD = 3 and 1 X 10(-10) M, respectively, at pH 7.5, 4 degrees C, and 100 mM NaCl). Chloride stabilizes the enzyme-inhibitor complex for each domain primarily by slowing its dissociation rate, as the k-1 values of the N and C domains are markedly decreased (about 30- and 1100-fold, respectively) by 300 mM NaCl. At high chloride concentrations, the chloride effect is much greater for the C domain than for the N domain resulting in a higher affinity of this inhibitor for the C domain. In addition, the inhibitory potency of captopril (C), enalaprilat (E), and lisinopril (L) for each domain was assayed by hydrolysis of Hip-His-Leu. Their Ki values for the two domains are all within the nanomolar range, indicating that they are all highly potent inhibitors for both domains. However, their relative potencies are different for the C domain (L greater than E greater than C) and the N domain (C greater than E greater than L). The different inhibitor binding properties of the two domains observed in the present study provide strong evidence for the presence of structural differences between the two active sites of ACE.
In the RAS (renin-angiotensin system), Ang I (angiotensin I) is cleaved by ACE (angiotensin-converting enzyme) to form Ang II (angiotensin II), which has effects on blood pressure, fluid and electrolyte homoeostasis. We have examined the kinetics of angiotensin peptide cleavage by full-length human ACE, the separate N- and C-domains of ACE, the homologue of ACE, ACE2, and NEP (neprilysin). The activity of the enzyme preparations was determined by active-site titrations using competitive tight-binding inhibitors and fluorogenic substrates. Ang I was effectively cleaved by NEP to Ang (1-7) (kcat/K(m) of 6.2x10(5) M(-1) x s(-1)), but was a poor substrate for ACE2 (kcat/K(m) of 3.3x10(4) M(-1) x s(-1)). Ang (1-9) was a better substrate for NEP than ACE (kcat/K(m) of 3.7x10(5) M(-1) x s(-1) compared with kcat/K(m) of 6.8x10(4) M(-1) x s(-1)). Ang II was cleaved efficiently by ACE2 to Ang (1-7) (kcat/K(m) of 2.2x10(6) M(-1) x s(-1)) and was cleaved by NEP (kcat/K(m) of 2.2x10(5) M(-1) x s(-1)) to several degradation products. In contrast with a previous report, Ang (1-7), like Ang I and Ang (1-9), was cleaved with a similar efficiency by both the N- and C-domains of ACE (kcat/K(m) of 3.6x10(5) M(-1) x s(-1) compared with kcat/K(m) of 3.3x10(5) M(-1) x s(-1)). The two active sites of ACE exhibited negative co-operativity when either Ang I or Ang (1-7) was the substrate. In addition, a range of ACE inhibitors failed to inhibit ACE2. These kinetic data highlight that the flux of peptides through the RAS is complex, with the levels of ACE, ACE2 and NEP dictating whether vasoconstriction or vasodilation will predominate.
Catalysis of the hydrolysis of peptide bonds by a mechanism in which water acts as a nucleophile, one or two metal ions hold the water molecule in place, and charged amino acid side chains are ligands for the metal ions.
J. Biol. Chem. 267, 13398-13405 (1992)[PubMed:1320019]
The endothelial angiotensin I-converting enzyme (ACE; EC 3.4.15.1) has recently been shown to contain two large homologous domains (called here the N and C domains), each being a zinc-dependent dipeptidyl carboxypeptidase. To further characterize the two active sites of ACE, we have investigated their interaction with four competitive ACE inhibitors, which are all potent antihypertensive drugs. The binding of [3H] trandolaprilat to the two active sites was examined using the wild-type ACE and four ACE mutants each containing only one intact domain, the other domain being either deleted or inactivated by point mutation of the zinc-coordinating histidines. In contrast with all the previous studies, which suggested the presence of a single high affinity inhibitor binding site in ACE, the present study shows that both the N and C domains of ACE contain a high affinity inhibitor binding site (KD = 3 and 1 X 10(-10) M, respectively, at pH 7.5, 4 degrees C, and 100 mM NaCl). Chloride stabilizes the enzyme-inhibitor complex for each domain primarily by slowing its dissociation rate, as the k-1 values of the N and C domains are markedly decreased (about 30- and 1100-fold, respectively) by 300 mM NaCl. At high chloride concentrations, the chloride effect is much greater for the C domain than for the N domain resulting in a higher affinity of this inhibitor for the C domain. In addition, the inhibitory potency of captopril (C), enalaprilat (E), and lisinopril (L) for each domain was assayed by hydrolysis of Hip-His-Leu. Their Ki values for the two domains are all within the nanomolar range, indicating that they are all highly potent inhibitors for both domains. However, their relative potencies are different for the C domain (L greater than E greater than C) and the N domain (C greater than E greater than L). The different inhibitor binding properties of the two domains observed in the present study provide strong evidence for the presence of structural differences between the two active sites of ACE.
To investigate how angiotensin I-converting enzyme (ACE) inhibitors enhance the actions of bradykinin (BK) on B2 receptors independent of blocking BK inactivation, we expressed human somatic ACE and B2 receptors in CHO cells. Bradykinin and its ACE-resistant analog were the receptor agonists. B2 fused with green fluorescent protein (GFP) and ACE were coprecipitated with antisera to GFP or ACE shown in Western blots. Immunohistochemistry of fixed cells localized ACE by red color and B2-GFP by green. Yellow on plasma membranes of coexpressing cells also indicated enzyme-receptor complex formation. Using ACE-fused cyan fluorescent protein donor and B2-fused yellow fluorescent protein (YFP) acceptor, we registered fluorescence resonance energy transfer (FRET) by the enhanced fluorescence of donor on acceptor photobleaching, establishing close (within 10 nm) positions of B2 receptors and ACE. Bradykinin stimulation cointernalized ACE and B2 receptors. We expressed ACE fused to N terminus of B2 receptors, anchoring only receptors to plasma membranes. Here, in contrast to cells, where both ACE and B2 receptors are separately anchored, ACE inhibitors neither enhance activation of chimeric B2 nor resensitize desensitized B2 receptors. Heterodimer formation between ACE and B2 receptors can be a mechanism for ACE inhibitors to augment kinin activity at cellular level.
Proc. Natl. Acad. Sci. U.S.A. 85, 9386-9390 (1988)[PubMed:2849100]
The amino-terminal amino acid sequence and several internal peptide sequences of angiotensin I-converting enzyme (ACE; peptidyl-dipeptidase A, kininase II; EC 3.4.15.1) purified from human kidney were used to design oligonucleotide probes. The nucleotide sequence of ACE mRNA was determined by molecular cloning of the DNA complementary to the human vascular endothelial cell ACE mRNA. The complete amino acid sequence deduced from the cDNA contains 1306 residues, beginning with a signal peptide of 29 amino acids. A highly hydrophobic sequence located near the carboxyl-terminal extremity of the molecule most likely constitutes the anchor to the plasma membrane. The sequence of ACE reveals a high degree of internal homology between two large domains, suggesting that the molecule resulted from a gene duplication. Each of these two domains contains short amino acid sequences identical to those located around critical residues of the active site of other metallopeptidases (thermolysin, neutral endopeptidase, and collagenase) and therefore bears a putative active site. Since earlier experiments suggested that a single Zn atom was bound per molecule of ACE, only one of the two domains should be catalytically active. The results of genomic DNA analysis with the cDNA probe are consistent with the presence of a single gene for ACE in the haploid human genome. Whereas the ACE gene is transcribed as a 4.3-kilobase mRNA in vascular endothelial cells, a 3.0-kilobase transcript was detected in the testis, where a shorter form of ACE is synthesized.
Protein Expr. Purif. 2, 1-9 (1991)[PubMed:1668266]
Enzymatically active human testis angiotensin-converting enzyme (ACE) was expressed in Chinese hamster ovary (CHO) cells stably transfected with each of three vectors: p omega-ACE contains a full-length testis ACE cDNA under the control of a retroviral promoter; and pLEN-ACEVII and pLEN-ACE6/5, in which full-length and membrane anchor-minus testis ACE cDNAs, respectively, are under the control of the human metallothionein IIA promoter and SV40 enhancer. In every case, active recombinant human testis ACE (hTACE) was secreted in a soluble form into the culture media, up to 2.4 mg/liter in the media of metal-induced, high-producing clones transfected with one of the pLEN vectors. In addition, membrane-bound recombinant enzyme was recovered from detergent extracts of cell pellets of CHO cells transfected with either p omega-ACE or pLEN-ACE-VII. Recombinant converting enzyme was purified to homogeneity by single-step affinity chromatography of conditioned media and detergent-extracted cell pellets in 85 and 70% overall yield, respectively. Purified hTACE from all sources comigrated with the native testis isozyme on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with M(r) approximately 100 kDa. The native and recombinant proteins cross-reacted equally with anti-human kidney ACE antiserum on Western blotting. The catalytic activity of recombinant angiotensin-converting enzyme, in terms of angiotensin I and 2-furanacryloyl-Phe-Gly-Gly hydrolysis, chloride activation, and lisinopril inhibition, was essentially identical to that of the native enzyme. The facile recovery in high yield of fully active hTACE from the media of stably transfected CHO cells provides a suitable system for investigating structure-function relationships in this enzyme.
J. Pharmacol. Exp. Ther. 297, 606-611 (2001)[PubMed:11303049]
The phosphinic peptide RXP 407 has recently been identified as the first potent selective inhibitor of the N-active site (domain) of angiotensin-converting enzyme (ACE) in vitro. The aim of this study was to probe the in vivo efficacy of this new ACE inhibitor and to assess its effect on the metabolism of AcSDKP and angiotensin I. In mice infused with increasing doses of RXP 407 (0.1--30 mg/kg/30 min), plasma concentrations of AcSDKP, a physiological substrate of the N-domain, increased significantly and dose dependently toward a plateau 4 to 6 times the basal levels. RXP 407 significantly and dose dependently inhibited ex vivo plasma ACE N-domain activity, whereas it had no inhibitory activity toward the ACE C-domain. RXP 407 (10 mg/kg) did not inhibit the pressor response to an i.v. angiotensin I bolus injection in mice. In contrast, lisinopril infusion (5 and 10 mg/kg/30 min) affected the metabolism of both AcSDKP and angiotensin I. Thus, RXP 407 is the first ACE inhibitor that might be used to control selectively AcSDKP metabolism with no effect on blood pressure regulation.
J. Biol. Chem. 267, 13398-13405 (1992)[PubMed:1320019]
The endothelial angiotensin I-converting enzyme (ACE; EC 3.4.15.1) has recently been shown to contain two large homologous domains (called here the N and C domains), each being a zinc-dependent dipeptidyl carboxypeptidase. To further characterize the two active sites of ACE, we have investigated their interaction with four competitive ACE inhibitors, which are all potent antihypertensive drugs. The binding of [3H] trandolaprilat to the two active sites was examined using the wild-type ACE and four ACE mutants each containing only one intact domain, the other domain being either deleted or inactivated by point mutation of the zinc-coordinating histidines. In contrast with all the previous studies, which suggested the presence of a single high affinity inhibitor binding site in ACE, the present study shows that both the N and C domains of ACE contain a high affinity inhibitor binding site (KD = 3 and 1 X 10(-10) M, respectively, at pH 7.5, 4 degrees C, and 100 mM NaCl). Chloride stabilizes the enzyme-inhibitor complex for each domain primarily by slowing its dissociation rate, as the k-1 values of the N and C domains are markedly decreased (about 30- and 1100-fold, respectively) by 300 mM NaCl. At high chloride concentrations, the chloride effect is much greater for the C domain than for the N domain resulting in a higher affinity of this inhibitor for the C domain. In addition, the inhibitory potency of captopril (C), enalaprilat (E), and lisinopril (L) for each domain was assayed by hydrolysis of Hip-His-Leu. Their Ki values for the two domains are all within the nanomolar range, indicating that they are all highly potent inhibitors for both domains. However, their relative potencies are different for the C domain (L greater than E greater than C) and the N domain (C greater than E greater than L). The different inhibitor binding properties of the two domains observed in the present study provide strong evidence for the presence of structural differences between the two active sites of ACE.
Protein Expr. Purif. 2, 1-9 (1991)[PubMed:1668266]
Enzymatically active human testis angiotensin-converting enzyme (ACE) was expressed in Chinese hamster ovary (CHO) cells stably transfected with each of three vectors: p omega-ACE contains a full-length testis ACE cDNA under the control of a retroviral promoter; and pLEN-ACEVII and pLEN-ACE6/5, in which full-length and membrane anchor-minus testis ACE cDNAs, respectively, are under the control of the human metallothionein IIA promoter and SV40 enhancer. In every case, active recombinant human testis ACE (hTACE) was secreted in a soluble form into the culture media, up to 2.4 mg/liter in the media of metal-induced, high-producing clones transfected with one of the pLEN vectors. In addition, membrane-bound recombinant enzyme was recovered from detergent extracts of cell pellets of CHO cells transfected with either p omega-ACE or pLEN-ACE-VII. Recombinant converting enzyme was purified to homogeneity by single-step affinity chromatography of conditioned media and detergent-extracted cell pellets in 85 and 70% overall yield, respectively. Purified hTACE from all sources comigrated with the native testis isozyme on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with M(r) approximately 100 kDa. The native and recombinant proteins cross-reacted equally with anti-human kidney ACE antiserum on Western blotting. The catalytic activity of recombinant angiotensin-converting enzyme, in terms of angiotensin I and 2-furanacryloyl-Phe-Gly-Gly hydrolysis, chloride activation, and lisinopril inhibition, was essentially identical to that of the native enzyme. The facile recovery in high yield of fully active hTACE from the media of stably transfected CHO cells provides a suitable system for investigating structure-function relationships in this enzyme.
Proc. Natl. Acad. Sci. U.S.A. 85, 9386-9390 (1988)[PubMed:2849100]
The amino-terminal amino acid sequence and several internal peptide sequences of angiotensin I-converting enzyme (ACE; peptidyl-dipeptidase A, kininase II; EC 3.4.15.1) purified from human kidney were used to design oligonucleotide probes. The nucleotide sequence of ACE mRNA was determined by molecular cloning of the DNA complementary to the human vascular endothelial cell ACE mRNA. The complete amino acid sequence deduced from the cDNA contains 1306 residues, beginning with a signal peptide of 29 amino acids. A highly hydrophobic sequence located near the carboxyl-terminal extremity of the molecule most likely constitutes the anchor to the plasma membrane. The sequence of ACE reveals a high degree of internal homology between two large domains, suggesting that the molecule resulted from a gene duplication. Each of these two domains contains short amino acid sequences identical to those located around critical residues of the active site of other metallopeptidases (thermolysin, neutral endopeptidase, and collagenase) and therefore bears a putative active site. Since earlier experiments suggested that a single Zn atom was bound per molecule of ACE, only one of the two domains should be catalytically active. The results of genomic DNA analysis with the cDNA probe are consistent with the presence of a single gene for ACE in the haploid human genome. Whereas the ACE gene is transcribed as a 4.3-kilobase mRNA in vascular endothelial cells, a 3.0-kilobase transcript was detected in the testis, where a shorter form of ACE is synthesized.
To investigate how angiotensin I-converting enzyme (ACE) inhibitors enhance the actions of bradykinin (BK) on B2 receptors independent of blocking BK inactivation, we expressed human somatic ACE and B2 receptors in CHO cells. Bradykinin and its ACE-resistant analog were the receptor agonists. B2 fused with green fluorescent protein (GFP) and ACE were coprecipitated with antisera to GFP or ACE shown in Western blots. Immunohistochemistry of fixed cells localized ACE by red color and B2-GFP by green. Yellow on plasma membranes of coexpressing cells also indicated enzyme-receptor complex formation. Using ACE-fused cyan fluorescent protein donor and B2-fused yellow fluorescent protein (YFP) acceptor, we registered fluorescence resonance energy transfer (FRET) by the enhanced fluorescence of donor on acceptor photobleaching, establishing close (within 10 nm) positions of B2 receptors and ACE. Bradykinin stimulation cointernalized ACE and B2 receptors. We expressed ACE fused to N terminus of B2 receptors, anchoring only receptors to plasma membranes. Here, in contrast to cells, where both ACE and B2 receptors are separately anchored, ACE inhibitors neither enhance activation of chimeric B2 nor resensitize desensitized B2 receptors. Heterodimer formation between ACE and B2 receptors can be a mechanism for ACE inhibitors to augment kinin activity at cellular level.
Interacting selectively and non-covalently with any protein or protein complex (a complex of two or more proteins that may include other nonprotein molecules).
Evidence
1:
Inferred from Physical InteractionUniProtKB
The phosphorylation of the short C-terminal cytoplasmic domain of the somatic angiotensin-converting enzyme (ACE) is involved in the regulation of enzyme shedding. We determined whether the phosphorylation of the cytoplasmic domain of ACE (ACEct) on Ser1270 regulates the cleavage/secretion of the enzyme by affecting its association with other proteins. ACE was associated with beta-actin and the nonmuscle myosin heavy chain IIA (MYH9) in endothelial cells, as determined by coimmunoprecipitation experiments as well as an ACEct affinity column. The ACE-associated MYH9 immunoprecipitated from (32)P-labeled endothelial cells was basally phosphorylated and cell stimulation with ACE inhibitors, or with bradykinin, increased the phosphorylation of MYH9. Casein kinase 2 (CK2) but not protein kinase C phosphorylated MYH9 in vitro, CK2 coprecipitated with MYH9 from endothelial cells and the phosphorylation of MYH9 in intact cells paralleled the phosphorylation of ACE on Ser1270 by CK2. The CK2 inhibitor 5,6-dichloro-1-beta-d-ribofuranosylbenzimidazole attenuated the phosphorylation of ACE and MYH9, disrupted their association, and enhanced the cleavage/secretion of ACE from the plasma membrane. Cytochalasin D decreased the interaction between ACE and MYH9 and stimulated ACE shedding. Although MYH9 was still able to associate with residual amounts of a nonphosphorylatable S1270A ACE mutant, no ACE inhibitor-induced increase in MYH9 phosphorylation could be detected in S1270A-expressing cells. These data indicate that the interaction of ACE with MYH9 determines ACE shedding and is modulated by phosphorylation processes. Furthermore, because ACE inhibitors affect the phosphorylation of MYH9, the phosphorylation of this class II myosin might contribute to the phenomenon of ACE signaling in endothelial cells.
Angiotensin-converting enzyme (ACE) has a critical role in cardiovascular function by cleaving the carboxy terminal His-Leu dipeptide from angiotensin I to produce a potent vasopressor octapeptide, angiotensin II. Inhibitors of ACE are a first line of therapy for hypertension, heart failure, myocardial infarction and diabetic nephropathy. Notably, these inhibitors were developed without knowledge of the structure of human ACE, but were instead designed on the basis of an assumed mechanistic homology with carboxypeptidase A. Here we present the X-ray structure of human testicular ACE and its complex with one of the most widely used inhibitors, lisinopril (N2-[(S)-1-carboxy-3-phenylpropyl]-L-lysyl-L-proline; also known as Prinivil or Zestril), at 2.0 A resolution. Analysis of the three-dimensional structure of ACE shows that it bears little similarity to that of carboxypeptidase A, but instead resembles neurolysin and Pyrococcus furiosus carboxypeptidase--zinc metallopeptidases with no detectable sequence similarity to ACE. The structure provides an opportunity to design domain-selective ACE inhibitors that may exhibit new pharmacological profiles.
Protein Expr. Purif. 2, 1-9 (1991)[PubMed:1668266]
Enzymatically active human testis angiotensin-converting enzyme (ACE) was expressed in Chinese hamster ovary (CHO) cells stably transfected with each of three vectors: p omega-ACE contains a full-length testis ACE cDNA under the control of a retroviral promoter; and pLEN-ACEVII and pLEN-ACE6/5, in which full-length and membrane anchor-minus testis ACE cDNAs, respectively, are under the control of the human metallothionein IIA promoter and SV40 enhancer. In every case, active recombinant human testis ACE (hTACE) was secreted in a soluble form into the culture media, up to 2.4 mg/liter in the media of metal-induced, high-producing clones transfected with one of the pLEN vectors. In addition, membrane-bound recombinant enzyme was recovered from detergent extracts of cell pellets of CHO cells transfected with either p omega-ACE or pLEN-ACE-VII. Recombinant converting enzyme was purified to homogeneity by single-step affinity chromatography of conditioned media and detergent-extracted cell pellets in 85 and 70% overall yield, respectively. Purified hTACE from all sources comigrated with the native testis isozyme on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with M(r) approximately 100 kDa. The native and recombinant proteins cross-reacted equally with anti-human kidney ACE antiserum on Western blotting. The catalytic activity of recombinant angiotensin-converting enzyme, in terms of angiotensin I and 2-furanacryloyl-Phe-Gly-Gly hydrolysis, chloride activation, and lisinopril inhibition, was essentially identical to that of the native enzyme. The facile recovery in high yield of fully active hTACE from the media of stably transfected CHO cells provides a suitable system for investigating structure-function relationships in this enzyme.
To investigate how angiotensin I-converting enzyme (ACE) inhibitors enhance the actions of bradykinin (BK) on B2 receptors independent of blocking BK inactivation, we expressed human somatic ACE and B2 receptors in CHO cells. Bradykinin and its ACE-resistant analog were the receptor agonists. B2 fused with green fluorescent protein (GFP) and ACE were coprecipitated with antisera to GFP or ACE shown in Western blots. Immunohistochemistry of fixed cells localized ACE by red color and B2-GFP by green. Yellow on plasma membranes of coexpressing cells also indicated enzyme-receptor complex formation. Using ACE-fused cyan fluorescent protein donor and B2-fused yellow fluorescent protein (YFP) acceptor, we registered fluorescence resonance energy transfer (FRET) by the enhanced fluorescence of donor on acceptor photobleaching, establishing close (within 10 nm) positions of B2 receptors and ACE. Bradykinin stimulation cointernalized ACE and B2 receptors. We expressed ACE fused to N terminus of B2 receptors, anchoring only receptors to plasma membranes. Here, in contrast to cells, where both ACE and B2 receptors are separately anchored, ACE inhibitors neither enhance activation of chimeric B2 nor resensitize desensitized B2 receptors. Heterodimer formation between ACE and B2 receptors can be a mechanism for ACE inhibitors to augment kinin activity at cellular level.
Protein Expr. Purif. 2, 1-9 (1991)[PubMed:1668266]
Enzymatically active human testis angiotensin-converting enzyme (ACE) was expressed in Chinese hamster ovary (CHO) cells stably transfected with each of three vectors: p omega-ACE contains a full-length testis ACE cDNA under the control of a retroviral promoter; and pLEN-ACEVII and pLEN-ACE6/5, in which full-length and membrane anchor-minus testis ACE cDNAs, respectively, are under the control of the human metallothionein IIA promoter and SV40 enhancer. In every case, active recombinant human testis ACE (hTACE) was secreted in a soluble form into the culture media, up to 2.4 mg/liter in the media of metal-induced, high-producing clones transfected with one of the pLEN vectors. In addition, membrane-bound recombinant enzyme was recovered from detergent extracts of cell pellets of CHO cells transfected with either p omega-ACE or pLEN-ACE-VII. Recombinant converting enzyme was purified to homogeneity by single-step affinity chromatography of conditioned media and detergent-extracted cell pellets in 85 and 70% overall yield, respectively. Purified hTACE from all sources comigrated with the native testis isozyme on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with M(r) approximately 100 kDa. The native and recombinant proteins cross-reacted equally with anti-human kidney ACE antiserum on Western blotting. The catalytic activity of recombinant angiotensin-converting enzyme, in terms of angiotensin I and 2-furanacryloyl-Phe-Gly-Gly hydrolysis, chloride activation, and lisinopril inhibition, was essentially identical to that of the native enzyme. The facile recovery in high yield of fully active hTACE from the media of stably transfected CHO cells provides a suitable system for investigating structure-function relationships in this enzyme.
The process in which a relatively unspecialized cell acquires specialized features of a hematopoietic stem cell. A stem cell is a cell that retains the ability to divide and proliferate throughout life to provide progenitor cells that can differentiate into specialized cells.
J. Biol. Chem. 270, 3656-3661 (1995)[PubMed:7876104]
Angiotensin I-converting enzyme (ACE) is a zinc-dipeptidyl carboxypeptidase, which contains two similar domains, each possessing a functional active site. Respective involvement of each active site in the degradation of the circulating peptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), a negative regulator of hematopoietic stem cell proliferation, was studied by using wild-type recombinant ACE and two full-length mutants containing a single functional site. Both the N- and C-active sites of ACE exhibit dipeptidyl activity toward AcSDKP, with Km values of 31 and 39 microM, respectively. However, the N-active site hydrolyzes the peptide 50 times faster compared with the C-active site, with kcat/Km values of 0.5 and 0.01 microM-1.s-1, respectively. The predominant role of the N-active site in AcSDKP hydrolysis was confirmed by the inhibition of hydrolysis using a monoclonal antibody specifically directed against the N-active site. The N-domain specificity for AcSDKP will aid the identification of specific inhibitors for this domain. This is the first report of a highly specific substrate for the N-active site of ACE, with kinetic constants in the range of physiological substrates, suggesting that ACE might be involved via its N-terminal active site in the in vivo regulation of the local concentration of this hemoregulatory peptide.
The chemical reactions and pathways resulting in the breakdown of any hormone, naturally occurring substances secreted by specialized cells that affects the metabolism or behavior of other cells possessing functional receptors for the hormone.
Evidence
1:
Inferred from Sequence or Structural SimilarityBHF-UCL
J. Pharmacol. Exp. Ther. 297, 606-611 (2001)[PubMed:11303049]
The phosphinic peptide RXP 407 has recently been identified as the first potent selective inhibitor of the N-active site (domain) of angiotensin-converting enzyme (ACE) in vitro. The aim of this study was to probe the in vivo efficacy of this new ACE inhibitor and to assess its effect on the metabolism of AcSDKP and angiotensin I. In mice infused with increasing doses of RXP 407 (0.1--30 mg/kg/30 min), plasma concentrations of AcSDKP, a physiological substrate of the N-domain, increased significantly and dose dependently toward a plateau 4 to 6 times the basal levels. RXP 407 significantly and dose dependently inhibited ex vivo plasma ACE N-domain activity, whereas it had no inhibitory activity toward the ACE C-domain. RXP 407 (10 mg/kg) did not inhibit the pressor response to an i.v. angiotensin I bolus injection in mice. In contrast, lisinopril infusion (5 and 10 mg/kg/30 min) affected the metabolism of both AcSDKP and angiotensin I. Thus, RXP 407 is the first ACE inhibitor that might be used to control selectively AcSDKP metabolism with no effect on blood pressure regulation.
J. Biol. Chem. 270, 3656-3661 (1995)[PubMed:7876104]
Angiotensin I-converting enzyme (ACE) is a zinc-dipeptidyl carboxypeptidase, which contains two similar domains, each possessing a functional active site. Respective involvement of each active site in the degradation of the circulating peptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), a negative regulator of hematopoietic stem cell proliferation, was studied by using wild-type recombinant ACE and two full-length mutants containing a single functional site. Both the N- and C-active sites of ACE exhibit dipeptidyl activity toward AcSDKP, with Km values of 31 and 39 microM, respectively. However, the N-active site hydrolyzes the peptide 50 times faster compared with the C-active site, with kcat/Km values of 0.5 and 0.01 microM-1.s-1, respectively. The predominant role of the N-active site in AcSDKP hydrolysis was confirmed by the inhibition of hydrolysis using a monoclonal antibody specifically directed against the N-active site. The N-domain specificity for AcSDKP will aid the identification of specific inhibitors for this domain. This is the first report of a highly specific substrate for the N-active site of ACE, with kinetic constants in the range of physiological substrates, suggesting that ACE might be involved via its N-terminal active site in the in vivo regulation of the local concentration of this hemoregulatory peptide.
The process whose specific outcome is the progression of the kidney over time, from its formation to the mature structure. The kidney is an organ that filters the blood and/or excretes the end products of body metabolism in the form of urine.
Autosomal recessive renal tubular dysgenesis is a severe disorder of renal tubular development characterized by persistent fetal anuria and perinatal death, probably due to pulmonary hypoplasia from early-onset oligohydramnios (Potter phenotype). Absence or paucity of differentiated proximal tubules is the histopathological hallmark of the disease and may be associated with skull ossification defects. We studied 11 individuals with renal tubular dysgenesis, belonging to nine families, and found that they had homozygous or compound heterozygous mutations in the genes encoding renin, angiotensinogen, angiotensin converting enzyme or angiotensin II receptor type 1. We propose that renal lesions and early anuria result from chronic low perfusion pressure of the fetal kidney, a consequence of renin-angiotensin system inactivity. This is the first identification to our knowledge of a renal mendelian disorder linked to genetic defects in the renin-angiotensin system, highlighting the crucial role of the renin-angiotensin system in human kidney development.
The expansion of a mononuclear cell population by cell division. A mononuclear cell is a leukocyte with a single non-segmented nucleus in the mature form.
J. Biol. Chem. 270, 3656-3661 (1995)[PubMed:7876104]
Angiotensin I-converting enzyme (ACE) is a zinc-dipeptidyl carboxypeptidase, which contains two similar domains, each possessing a functional active site. Respective involvement of each active site in the degradation of the circulating peptide N-acetyl-seryl-aspartyl-lysyl-proline (AcSDKP), a negative regulator of hematopoietic stem cell proliferation, was studied by using wild-type recombinant ACE and two full-length mutants containing a single functional site. Both the N- and C-active sites of ACE exhibit dipeptidyl activity toward AcSDKP, with Km values of 31 and 39 microM, respectively. However, the N-active site hydrolyzes the peptide 50 times faster compared with the C-active site, with kcat/Km values of 0.5 and 0.01 microM-1.s-1, respectively. The predominant role of the N-active site in AcSDKP hydrolysis was confirmed by the inhibition of hydrolysis using a monoclonal antibody specifically directed against the N-active site. The N-domain specificity for AcSDKP will aid the identification of specific inhibitors for this domain. This is the first report of a highly specific substrate for the N-active site of ACE, with kinetic constants in the range of physiological substrates, suggesting that ACE might be involved via its N-terminal active site in the in vivo regulation of the local concentration of this hemoregulatory peptide.
The chemical reactions and pathways resulting in the breakdown of peptides, compounds of 2 or more (but usually less than 100) amino acids where the alpha carboxyl group of one is bound to the alpha amino group of another.
Any process that modulates the force with which blood travels through the circulatory system. The process is controlled by a balance of processes that increase pressure and decrease pressure.
Evidence
2:
Inferred from Sequence or Structural SimilarityBHF-UCL
J. Pharmacol. Exp. Ther. 297, 606-611 (2001)[PubMed:11303049]
The phosphinic peptide RXP 407 has recently been identified as the first potent selective inhibitor of the N-active site (domain) of angiotensin-converting enzyme (ACE) in vitro. The aim of this study was to probe the in vivo efficacy of this new ACE inhibitor and to assess its effect on the metabolism of AcSDKP and angiotensin I. In mice infused with increasing doses of RXP 407 (0.1--30 mg/kg/30 min), plasma concentrations of AcSDKP, a physiological substrate of the N-domain, increased significantly and dose dependently toward a plateau 4 to 6 times the basal levels. RXP 407 significantly and dose dependently inhibited ex vivo plasma ACE N-domain activity, whereas it had no inhibitory activity toward the ACE C-domain. RXP 407 (10 mg/kg) did not inhibit the pressor response to an i.v. angiotensin I bolus injection in mice. In contrast, lisinopril infusion (5 and 10 mg/kg/30 min) affected the metabolism of both AcSDKP and angiotensin I. Thus, RXP 407 is the first ACE inhibitor that might be used to control selectively AcSDKP metabolism with no effect on blood pressure regulation.
Protein Expr. Purif. 2, 1-9 (1991)[PubMed:1668266]
Enzymatically active human testis angiotensin-converting enzyme (ACE) was expressed in Chinese hamster ovary (CHO) cells stably transfected with each of three vectors: p omega-ACE contains a full-length testis ACE cDNA under the control of a retroviral promoter; and pLEN-ACEVII and pLEN-ACE6/5, in which full-length and membrane anchor-minus testis ACE cDNAs, respectively, are under the control of the human metallothionein IIA promoter and SV40 enhancer. In every case, active recombinant human testis ACE (hTACE) was secreted in a soluble form into the culture media, up to 2.4 mg/liter in the media of metal-induced, high-producing clones transfected with one of the pLEN vectors. In addition, membrane-bound recombinant enzyme was recovered from detergent extracts of cell pellets of CHO cells transfected with either p omega-ACE or pLEN-ACE-VII. Recombinant converting enzyme was purified to homogeneity by single-step affinity chromatography of conditioned media and detergent-extracted cell pellets in 85 and 70% overall yield, respectively. Purified hTACE from all sources comigrated with the native testis isozyme on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with M(r) approximately 100 kDa. The native and recombinant proteins cross-reacted equally with anti-human kidney ACE antiserum on Western blotting. The catalytic activity of recombinant angiotensin-converting enzyme, in terms of angiotensin I and 2-furanacryloyl-Phe-Gly-Gly hydrolysis, chloride activation, and lisinopril inhibition, was essentially identical to that of the native enzyme. The facile recovery in high yield of fully active hTACE from the media of stably transfected CHO cells provides a suitable system for investigating structure-function relationships in this enzyme.
Protein Expr. Purif. 2, 1-9 (1991)[PubMed:1668266]
Enzymatically active human testis angiotensin-converting enzyme (ACE) was expressed in Chinese hamster ovary (CHO) cells stably transfected with each of three vectors: p omega-ACE contains a full-length testis ACE cDNA under the control of a retroviral promoter; and pLEN-ACEVII and pLEN-ACE6/5, in which full-length and membrane anchor-minus testis ACE cDNAs, respectively, are under the control of the human metallothionein IIA promoter and SV40 enhancer. In every case, active recombinant human testis ACE (hTACE) was secreted in a soluble form into the culture media, up to 2.4 mg/liter in the media of metal-induced, high-producing clones transfected with one of the pLEN vectors. In addition, membrane-bound recombinant enzyme was recovered from detergent extracts of cell pellets of CHO cells transfected with either p omega-ACE or pLEN-ACE-VII. Recombinant converting enzyme was purified to homogeneity by single-step affinity chromatography of conditioned media and detergent-extracted cell pellets in 85 and 70% overall yield, respectively. Purified hTACE from all sources comigrated with the native testis isozyme on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with M(r) approximately 100 kDa. The native and recombinant proteins cross-reacted equally with anti-human kidney ACE antiserum on Western blotting. The catalytic activity of recombinant angiotensin-converting enzyme, in terms of angiotensin I and 2-furanacryloyl-Phe-Gly-Gly hydrolysis, chloride activation, and lisinopril inhibition, was essentially identical to that of the native enzyme. The facile recovery in high yield of fully active hTACE from the media of stably transfected CHO cells provides a suitable system for investigating structure-function relationships in this enzyme.
Protein Expr. Purif. 2, 1-9 (1991)[PubMed:1668266]
Enzymatically active human testis angiotensin-converting enzyme (ACE) was expressed in Chinese hamster ovary (CHO) cells stably transfected with each of three vectors: p omega-ACE contains a full-length testis ACE cDNA under the control of a retroviral promoter; and pLEN-ACEVII and pLEN-ACE6/5, in which full-length and membrane anchor-minus testis ACE cDNAs, respectively, are under the control of the human metallothionein IIA promoter and SV40 enhancer. In every case, active recombinant human testis ACE (hTACE) was secreted in a soluble form into the culture media, up to 2.4 mg/liter in the media of metal-induced, high-producing clones transfected with one of the pLEN vectors. In addition, membrane-bound recombinant enzyme was recovered from detergent extracts of cell pellets of CHO cells transfected with either p omega-ACE or pLEN-ACE-VII. Recombinant converting enzyme was purified to homogeneity by single-step affinity chromatography of conditioned media and detergent-extracted cell pellets in 85 and 70% overall yield, respectively. Purified hTACE from all sources comigrated with the native testis isozyme on sodium dodecyl sulfate-polyacrylamide gel electrophoresis with M(r) approximately 100 kDa. The native and recombinant proteins cross-reacted equally with anti-human kidney ACE antiserum on Western blotting. The catalytic activity of recombinant angiotensin-converting enzyme, in terms of angiotensin I and 2-furanacryloyl-Phe-Gly-Gly hydrolysis, chloride activation, and lisinopril inhibition, was essentially identical to that of the native enzyme. The facile recovery in high yield of fully active hTACE from the media of stably transfected CHO cells provides a suitable system for investigating structure-function relationships in this enzyme.
This protein acts as an enzyme. It is known to catalyze the following reaction
EC 3.4.15.1: Release of a C-terminal dipeptide, oligopeptide-|-Xaa-Yaa, when Xaa is not Pro, and Yaa is neither Asp nor Glu. Thus, conversion of angiotensin I to angiotensin II, with increase in vasoconstrictor activity, but no action on angiotensin II.
Enzyme which catalyzes hydrolysis reaction, i.e. the addition of the hydrogen and hydroxyl ions of water to a molecule with its consequent splitting into two or more simpler molecules.
A reference proteome is a set of protein sequences derived from a complete proteome which constitutes a defined standard for a particular user community. Reference proteomes are manually defined according to a number of criteria. They cover the proteomes of well- studied model organisms and other proteomes of interest for biomedical and biotechnological research. Reference proteomes have been selected to provide broad coverage of the tree of life, and constitute a representative cross-section of the taxonomic diversity to be found within UniProtKB.