Field desorption mass spectra of tryptic peptides of human hemoglobin chains

Abstract

Field desorption mass spectra of tryptic peptides of normal human hemoglobin a-, p-, y-, 8-chains and abnormal @-chain of hemoglobin S were studied. Almost all mass peaks of the protonated molecular ions of tryptic peptides and many doubly charged ions were observed. The molecular weights of all tryptic peptides were estimated from the mass spectra, the heaviest mass being m/r 2955, and coincided with the values obtained from the known amino acid sequences. The different chains of hemoglobin can be distinguished by their field desorption mass spectra. The mass spectrum of abnormal @-chain of hernoglobin S (sickle-cell-anemia) showed a shift of the characteristic line due to the mutation of amino acid.

Rapid Analysis of Hemoglobin from Whole Human Blood by Matrix-assisted Laser Desorption/Ionization Time-of-flight Mass Spectrometry

“…The first such study, conducted by Matsuo et al, used field desorption mass spectrometry of tryptic fragments to distinguish HbS from normal hemoglobin (HbA). 10 Shortly thereafter, fast atom bombardment (FAB) [11][12][13][14] and liquid secondary ion mass spectrometry 4,7,15,16 were utilized, proving to be more reliable and reproducible than field desorption. 13 Later, analysis by plasma desorption (PD) was demonstrated to be similarly effective.…”

High‐field‐magnet mass spectrometry of biological molecules

“…The few genuine problems examined by FD have mostly been performed using high-mass instrumentation. Matsuo and colleagues (29) have developed FD methods for analysing enzymically generated peptide fragments of human haemoglobin. They showed that protonated molecular ions for all tryptic peptides could be observed using their large instrument.…”

Methods of Protein Microcharacterization

“…Field-desorption mass spectrometry has been used to analyze mixtures of peptides obtained by enzyme or chemical degradation of proteins that are too large to analyze directly (92). Like enzyme digest maps obtained by HPLC, such information is very useful for comparing proteins that have a large degree of homology.…”