title: Temperature-induced selective death of the C-domain within angiotensin-converting enzyme molecule.
abstract: Somatic angiotensin-converting enzyme (ACE) consists of two homologous domains, each domain bearing a catalytic site. Differential scanning calorimetry of the enzyme revealed two distinct thermal transitions with melting points at 55.3 and 70.5 degrees C. which corresponded to denaturation of C- and N-domains, respectively. Different heat stability of the domains underlies the methods of acquiring either single active N-domain or active N-domain with inactive C-domain within parent somatic ACE. Selective denaturation of C-domain supports the hypothesis of independent folding of the two domains within the ACE molecule. Modeling of ACE secondary structure revealed the difference in predicted structures of the two domains, which, in turn, allowed suggestion of the region 29-133 in amino acid sequence of the N-part of the molecule as responsible for thermostability of the N-domain.
authors.affiliation: Chemistry Department, M.V. Lomonosov Moscow State University, Russia.
authors.forename: Sergei
authors.initials: S
authors.lastname: Voronov
authors.forename: Natalia
authors.initials: N
authors.lastname: Zueva
authors.forename: Victor
authors.initials: V
authors.lastname: Orlov
authors.forename: Alexander
authors.initials: A
authors.lastname: Arutyunyan
authors.forename: Olga
authors.initials: O
authors.lastname: Kost
mesh_terms: D000595:Amino Acid Sequence; D000818:Animals; D002152:Calorimetry, Differential Scanning; D020134:Catalytic Domain; D002417:Cattle; D002942:Circular Dichroism; D004789:Enzyme Activation; D004795:Enzyme Stability; D006361:Heating; D008958:Models, Molecular; D008969:Molecular Sequence Data; D007703:Peptidyl-Dipeptidase A / Q000737:chemistry / Q000378:metabolism*; D011489:Protein Denaturation; D017433:Protein Structure, Secondary; D017386:Sequence Homology, Amino Acid; D013696:Temperature
chemical_list: D007703:Peptidyl-Dipeptidase A