Assignment of the ions in the electrospray ionization mass spectra of the tryptic digest of the non-derivatized globin, covering the whole sequence of α- and β-chains: A rapid diagnosis for haemoglobinopathy
✍ Scribed by Toyofumi Nakanishi; Masahiko Kishikawa; Akira Shimizu; Akira Hayashi; Fumio Inoue
- Publisher
- John Wiley and Sons
- Year
- 1995
- Tongue
- English
- Weight
- 527 KB
- Volume
- 30
- Category
- Article
- ISSN
- 1076-5174
No coin nor oath required. For personal study only.
✦ Synopsis
Abstract
For the rapid and simple identification of haemoglobin variants, tryptic peptides prepared by digestion of the mixture of normal and variant subunits were analysed by electrospray ionization mass spectrometry (ESI‐MS). The globin was not reduced and alkylated. In a single spectrum from the ESI analysis of tryptic digests from normal adult globin, nearly 90 significant peaks were observed. Many of these peaks had the right mass and yielded tandem mass spectra of sufficient quality to define the sequence. Some ion peaks were assigned mainly by mass values with additional indirect evidence. A series of multiply charged ions were observed and these ions were valuable for making the assignments. Ion peaks which were assigned with some degree of certainty covered whole sequence from α‐and β‐subunits. In addition to the normal ion peaks, variant ion peaks were observed in the analysis of tryptic peptides of the non‐derivatized globin mixture from Hb SC double heterozygote and from Hb M~Boston~ heterozygote. This approach will offer routine methods in clinical laboratories.