title: Determination of the structure of lipid vesicle-bound angiotensin II and angiotensin I.
abstract: A mass spectrometry (MS)-based strategy was developed to determine the structure of lipid vesicle-bound angiotensin II (AII) and angiotensin I (AI). It involves hydrogen-deuterium exchange (HDX), chemical modifications (e.g., nitration of tyrosine, acetylation of free amino group), and ladder sequencing. HDX is also combined with tandem mass spectrometry (MS/MS) to provide structural details at individual amino acid residues. It was observed that a major portion of both of these peptide hormones interacts with the phospholipid head groups on the surface of the vesicles and that Tyr residue is embedded in the vesicles. Both peptides have a U-shaped structure in the lipid environment.
authors.affiliation: Department of Chemistry, University of Memphis, Memphis, TN 38152, USA. cdass@memphis.edu
authors.forename: Pegah R
authors.initials: PR
authors.lastname: Jalili
authors.forename: Chhabil
authors.initials: C
authors.lastname: Dass
mesh_terms: D000595:Amino Acid Sequence; D000803:Angiotensin I / Q000737:chemistry*; D000804:Angiotensin II / Q000737:chemistry*; D041961:Deuterium Exchange Measurement; D008081:Liposomes; D010743:Phospholipids / Q000737:chemistry*; D011487:Protein Conformation; D021241:Spectrometry, Mass, Electrospray Ionization; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; D053719:Tandem Mass Spectrometry; D014443:Tyrosine
chemical_list: D008081:Liposomes; D010743:Phospholipids; D000804:Angiotensin II; D014443:Tyrosine; D000803:Angiotensin I