Interaction of angiotensin peptides and zinc metal ions probed by electrospray ionization mass spectrometry

✍ Scribed by Joseph A. Loo; Peifeng Hu; Richard D. Smith

• Publisher: Elsevier Science
• Year: 1994
• Tongue: English
• Weight: 707 KB
• Volume: 5
• Category: Article
• ISSN: 1044-0305
• DOI: 10.1016/1044-0305(94)80014-6

✦ Synopsis

Electrospray ionization-tandem mass spectrometry experiments were used to provide evidence regarding the sites of interactions between zinc metal ions and angiotensin peptides. The electrospray ionization mass spectra of histidine-containing human angiotensin II (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe) and angiotensin I (Asp-Arg-Val-Tyr-Ile-His-Pro-Phe-His-Leu) in the presence of zinc show abundant multiply charged ions for the zinc-attached peptide M + aZn(2+) +(c - 2a)H(+), where a = 1, 2 and c is charge. From collisionally activated dissociation experiments, with both low energy (triple quadrupole mass spectrometry) and high energy collisions (linked scan at constant B/E with a double focusing instrument) of the M + Zn and M + Zn + H ions for angiotensin II, a b 6 + Zn species is produced as the most abundant product ion, suggesting that the zinc interaction site is in the vicinity of the His(6) residue. Additionally, tandem mass spectra from the zinc-attached ions for angiotensin I show abundant b 6 + Zn and b 9 + Zn products, providing evidence that both His(6) and His(9) are involved in zinc coordination.