Fosfopeptitlerin Çözünmeyen Geçiş Metal Oksitleri Üzerinde Seçimli Zenginleştirilmesi ve Maldı-Ms İle Doğrudan Tayinleri

Abstract

Post-translational modifications organize cellular activities. One of the most common post-translational modifications is phosphorylation. Phosphorylation is the reversible covalent attachment of one ore more phosphate group to the protein structure. It is important to know which protein phosphorylates, or when the phosphorilation begins, for understanding intracellular signal transportation mechanism. Nowadays, mass spectrometry is used as the most efficient technique for characterizing phosphoproteins taking charge in cellular processes. However, phoshopeptides have low ionization efficiency which is a very important parameter for mass spectrometry. Furthermore, the concentration of phosphopeptides is usually lower than the detection limit of mass spectrometric techniques because of the substoichiometric phosphorylation. Therefore, selective enrichment and preconcentration is required to overcome all these issues before the mass spectrometric analysis of phosphopeptides.