Relative Quantitation of Beta-Amyloid Peptide Isomers with Simultaneous Isomerization of Multiple Aspartic Acid Residues by Matrix Assisted Laser Desorption Ionization-Time of Flight Mass Spectrometry.
Daniil G IvanovMaria I IndeykinaStanislav I PekovAnna E BugrovaOlga I KechkoAdel E IusupovAlexey S KononikhinAlexander A MakarovEugene N NikolaevIgor A PopovPublished in: Journal of the American Society for Mass Spectrometry (2019)
Matrix assisted laser desorption ionization-time of flight (MALDI-TOF) mass spectrometry can be used for rapid quantitation of peptides with various post-translational modifications (PTM), even if they do not shift the mass of the native peptide. Previously, it was shown that MALDI-TOF MS can be used for quantitation of isoD7 beta-amyloid 1-42 peptide. On the basis of the differences in the collision-induced dissociation fragmentation pattern of native Aβ, isoD7 Aβ, isoD23 Aβ, and isoD7_23 peptide (a di-isomerized peptide with both isomerization of D7 and D23 residues), we developed a MALDI-TOF-based method for simultaneous quantitation of all of these isoforms. Using multivariate regression for analysis of fragment MS data, the method allows the determination of the molar fractions of all of these isoforms with up to 16% error for mixtures with 2 pmol total amount of the beta-amyloid peptide.
Keyphrases
- mass spectrometry
- liquid chromatography
- ms ms
- high performance liquid chromatography
- capillary electrophoresis
- gas chromatography
- high resolution
- tandem mass spectrometry
- solid phase extraction
- liquid chromatography tandem mass spectrometry
- multiple sclerosis
- escherichia coli
- simultaneous determination
- staphylococcus aureus
- oxidative stress
- drug induced
- data analysis
- biofilm formation