醣基化修飾於血紅蛋白β亞基上N端的纈氨酸胺基上面形成所謂的糖化血紅蛋白被視為檢測是否為糖尿病或其他疾病的一個生物指標。然而，血紅蛋白醣基化是依據動力學結果而發生在不同亞基血紅蛋白之複數位置端上，並且相關的差異討論並沒有很詳細的全面報導。
本實驗將從正常與糖尿病患之血液中萃取出血紅蛋白並經由蛋白質沉澱方式，進行直接注射分析和利用top down方法配合液相層析質譜儀，或是搭配bottom-up方式利用不同蛋白質水解酵素胰蛋白酶、胰凝乳蛋白酶、蛋白内切酶進行酵素水解消化策略並且液相串聯式質譜儀進行不同特性的分析。所得質譜數據經由質譜軟體(Mascot)進行自動數據資料庫搜索後，經由手動分析數據方式獲得結果。
整體蛋白分析顯示了葡萄糖形成醣基化修飾與商業用檢測醣基化血紅蛋白比例具有一定程度良好相關性。而不同水解酵素進行水解消化策略則顯示可以鑑定血紅蛋白主要兩個亞基α與β的基本結構序列覆蓋率達到100%以及7個醣基化修飾位置。由資料顯示除了主要β亞基之N端(β-Val-1)，還有兩個主要醣基化修飾位置於β-Lys-66 和α-Lys-61包含了一段相同的序列HGKK。此外，四個次要醣基化位置相對比例少於1%的α-Val-1, β-Lys-132, α-Lys-127 和α-Lys-40皆可以得明顯鑑定。所有醣基化修飾位置之醣基化程度皆可顯示出隨著葡萄糖濃度上升。還有在修飾位置α-Val-1上也發現了另一主要修飾氨基甲酰化與葡糖糖濃度不具有相關趨勢。藉由分子模型預測可得知整個血紅蛋白序列的3D結構圖中，包含了相關序列HGKK位置環境顯示了符合與相關文獻報導容易造成醣基化環境相符。
最後利用bottom-up資訊利用搜尋軟體做一全轉譯後修飾的搜尋可以發現不同類型的修飾存在，可以反映不同樣品之間血紅蛋白上面其他差異性。
本研究進行了對於血紅蛋白醣基化發生的全面性比較在正常和糖尿病患者。由七個位點修飾含量百分比具有相似的趨勢可以反應糖化血色素可以提供的血糖濃度。這樣結果希望能提出新的見解對於HbA1c參數並且這套分析方法另外可以分析出血紅蛋白上面其他轉譯後修飾未來可以應用於判斷有效的其他生物指標關於糖尿病詳細併發症討論。

In this study, hemoglobin was extracted from the blood of normal and diabetic. Triplicate solutions prepared from each sample were directly analyzed via top down approach or digested with multiple enzymes and then analyzed by nano-LC/MS via bottom-up approach for characterization. Intact hemoglobin analysis indicated a single glucose-dominant glycation, which showed good correlation with the HbA1c% values and the sequence information was obtained by collision-induced dissociation of the resulting fragment ions can be extended. Moreover, full sequence (100 %) of α/β globin was mapped and seven glycation sites were unambiguously assigned. In addition to β-Val-1, two other major sites at α-Lys-61 and β-Lys-66, which contain the common sequence HGKK, and four minor sites on α-Val-1, β-Lys-132, α-Lys-127, and α-Lys-40 were identified. All sites were shown to exhibit similar patterns of site distribution despite different glucose levels. Both the intact mass measurement and bottom-up data consistently indicated that the total glycation percentage of the β-globin was twice higher than the α-globin. Using molecular modeling, the 3D structure of the consensus sequence (HGKK) was shown to contain a phosphate triangle cavity, which helps to catalyze the glycation reaction. Finally, compare the difference of mass gap between intact protein spectra and digest peptide PTM search which may exist other posttranslational modification in different sample. For the first time, hemoglobin glycation in normal and diabetic bloods was comparatively characterized in-depth. The results provide insight about the HbA1c parameter and help define the new and old markers.

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