The influence of strongly acidic groups on the protonation of peptides in electrospray MS

• Published in: Journal of mass spectrometry. Vol. 32; no. 10; pp. 1117 - 1123
• Main Authors: Svoboda, Michal, Meister, Walter, Kitas, Eric A., Vetter, Walter
• Format: Journal Article
• Language: English
• Published: Chichester, UK John Wiley & Sons, Ltd 01-10-1997; Wiley
• Subjects: Amino Acid Sequence; Amino Acids - analysis; Aminoacids, peptides. Hormones. Neuropeptides; Analytical, structural and metabolic biochemistry; Biological and medical sciences; Chemistry; electrospray; Exact sciences and technology; Fundamental and applied biological sciences. Psychology; Mass Spectrometry; Molecular Sequence Data; Organic chemistry; Oxidation-Reduction; oxidized peptides; peptides; Peptides - chemistry; Phosphates - analysis; phosphopeptides; Proteins; protonation; Protons; Reactivity and mechanisms; Structure effect; Analysis method; Investigation method; Oligopeptides; Peptides; Sulfur peptide; Phosphonic acids; Protonation; Mass spectrometry; Sulfonic acid; Electrospray; Functional group
• ISSN: 1076-5174; 1096-9888
• DOI: 10.1002/(SICI)1096-9888(199711)32:10<1117::AID-JMS568>3.0.CO;2-D

In order to obtain experimental data on the question of compensation of positive charges by anionic groups in multiply charged ions of polyfunctional molecules in electrospray MS, several pairs of peptides with the same basic structure but differentiated by one or two strongly acidic groups (phosphate or sulfonate) were investigated. It was found that depending on the density of basic centers and the strength of acidic groups present, the observed changes upon introduction of acidic groups ranged from complete elimination of the most highly charged state to absence of any difference. © 1997 John Wiley & Sons, Ltd.