Hemopressin forms self-assembled fibrillar nanostructures under physiologically relevant conditions.
The nonapeptide hemopressin, which is derived from the α chain of hemoglobin, has been reported to exhibit inverse agonist activity against the CB1 receptor. Administration of this peptide in animal models led to decreased food intake and elicited hypotensive and antinociceptive effects. On the basis of hemopressin's potential in therapeutic applications and the lack of a structure-activity relationship study in literature, we aimed to determine the conformational features of hemopressin under physiological conditions. We conducted transmission electron microscopy experiments of hemopressin, revealing that it self-assembles into fibrils under aqueous conditions at pH 7.4. Circular dichroism and nuclear magnetic resonance experiments indicate that the peptide adopts a mostly extended β-like structure, which may contribute to its self-assembly and fibril formation.
Center for Advanced Drug Research (CADRE),  SRI International , 140 Research Drive, Harrisonburg, Virginia 22802, United States.
Martha G
MG
Bomar
Steven J
SJ
Samuelsson
Patrick
P
Kibler
Krishna
K
Kodukula
Amit K
AK
Galande
D000818:Animals; D002942:Circular Dichroism; D006454:Hemoglobins / Q000737:chemistry* / Q000378:metabolism*; D006863:Hydrogen-Ion Concentration; D046529:Microscopy, Electron, Transmission; D008958:Models, Molecular; D049329:Nanostructures; D010446:Peptide Fragments / Q000737:chemistry* / Q000378:metabolism*; D051381:Rats; D043884:Receptor, Cannabinoid, CB1 / Q000819:agonists; D013329:Structure-Activity Relationship
D006454:Hemoglobins; D010446:Peptide Fragments; D043884:Receptor, Cannabinoid, CB1; C473218:hemopressin