Monitoring protein glycation by electrospray ionization (ESI) quadrupole time-of-flight (Q-TOF) mass spectrometer.
In this study electrospray ionization quadrupole time-of-flight (ESI-Q-TOF) mass spectrometry was used to investigate protein glycation. The glycated species of cytochrome C, lysozyme, and β-casein formed during glycation with d-glucose were identified and monitored in binary systems heated at 70°C under dry and aqueous conditions. Cytochrome C had multiple charges in non-glycated state, primarily changing from +13 to +17 positive charges, whereas β-casein had charge states up to +30. Upon heating with glucose at 70°C in aqueous state, attachment of one glucose molecule onto proteins was observed in each charge state. However, heating in dry state caused much more glucose attachment, leading to the formation of multiple glycoforms of proteins. By using ESI-QTOF-MS technique, formation of glycated cytochrome C containing up to 12 glucose moieties were observed, while glycated species containing 6 and 8 glucose moieties were observed for lysozyme and β-casein, respectively in various heating conditions.
Food Quality and Safety (FoQuS) Research Group, Department of Food Engineering, Hacettepe University, 06800 Beytepe Campus, Ankara, Turkey.
H Gül
HG
Akıllıoğlu
Department of Chemistry, Hacettepe University, 06800 Beytepe Campus, Ankara, Turkey.
Ömür
Ö
Çelikbıçak
Department of Chemistry, Hacettepe University, 06800 Beytepe Campus, Ankara, Turkey.
Bekir
B
Salih
Food Quality and Safety (FoQuS) Research Group, Department of Food Engineering, Hacettepe University, 06800 Beytepe Campus, Ankara, Turkey. Electronic address: vgokmen@hacettepe.edu.tr.
Vural
V
Gökmen
D000818:Animals; D002364:Caseins / Q000378:metabolism*; D045304:Cytochromes c / Q000378:metabolism*; D005947:Glucose / Q000378:metabolism*; D006031:Glycosylation; D009113:Muramidase / Q000378:metabolism*; D021241:Spectrometry, Mass, Electrospray Ionization / Q000379:methods*
D002364:Caseins; D045304:Cytochromes c; D009113:Muramidase; D005947:Glucose
Cytochrome C; Electrospray ionization quadrupole time-of-flight mass spectrometry; Lysozyme; Protein glycation; β-casein