Conformational Differences between Active Angiotensins and Their Inactive Precursors.
The peptide conformation in the context of a protein polypeptide chain is influenced by proximal amino acid residues. However, the mechanisms of this interference remain poorly understood. We studied the conformation of angiotensins 1, 2 and 3, which are produced naturally in a sequential fashion from a precursor protein angiotensinogen and contain an identical peptide core structure. Using the example of angiotensins 1, 2 and 3, it was shown that similar amino acid sequences may have significant conformational differences in various molecules. In order to assess the conformational changes, we developed a panel of high-affinity mouse monoclonal antibodies against angiotensins 1, 2 and 3 and studied their cross-reactivity in indirect and competitive ELISAs. It was found that the conformations of inactive angiotensin1 and the corresponding fragment of angiotensinogen are similar; the same is true for the conformations of active angiotensins 2 and 3, whereas the conformations of homologous fragments in the active and inactive angiotensins differ significantly.
Russian Research Center for Molecular Diagnostics and Therapy.
O N
ON
Solopova
L P
LP
Pozdnyakova
N E
NE
Varlamov
M N
MN
Bokov
E V
EV
Morozkina
Capital Te Cyrillic А
CT
Yagudin
P G
PG
Sveshnikov