当前位置: X-MOL 学术FEBS J. › 论文详情
Our official English website, www.x-mol.net, welcomes your feedback! (Note: you will need to create a separate account there.)
Structural analysis of glycated human hemoglobin using native mass spectrometry.
The FEBS Journal ( IF 5.5 ) Pub Date : 2019-10-09 , DOI: 10.1111/febs.15085
Monita Muralidharan 1 , Vijay Bhat 2 , Amit Kumar Mandal 1
Affiliation  

Glycated hemoglobin (GHb) is the indicator of the long-term glycemic index of an individual. GHb is formed by the irreversible modification of N-terminal α-amino group of β globin chain with glucose via Amadori rearrangement. Cation exchange chromatography exploits the difference in surface charges between GHb and native hemoglobin (HbA0 ) for their separation and quantification. However, glucose condensation is specific to primary amino groups. Therefore, structural characterization of GHb synthesized in vivo is essential as multiple glycation may interfere with GHb assessment. The stoichiometric composition of different glycated hemoglobin from a 19% GHb sample was deduced using native mass spectrometry. We observed a comparable population of α and β glycated tetramers for mono-glycated HbA0 . Surprisingly, doubly and triply glycated HbA0 also showed mono-glycated α and β globins. Thus, we propose that glycation of hemoglobin (HbA) occurs symmetrically across α and β globins with preference to unmodified globin first. Correlation between conventional and mass spectrometry-based quantification of GHb showed a reliable estimation of the glycemic index of individuals carrying HbA0 . Mutant HbAs have different retention time than HbA0 due to the differences in their surface charge. Thus, their glycated analog may elute at different retention time compared to GHb. Consequently, our method would be ideal for assessing the glycemic index of an individual carrying mutant HbA.

中文翻译:

使用天然质谱分析糖化人血红蛋白的结构。

糖化血红蛋白(GHb)是个体长期血糖指数的指标。GHb是通过Amadori重排用葡萄糖对β珠蛋白链的N端α-氨基进行不可逆修饰而形成的。阳离子交换色谱利用GHb和天然血红蛋白(HbA0)之间的表面电荷差异进行分离和定量。但是,葡萄糖缩合是伯氨基特有的。因此,体内合成的GHb的结构表征至关重要,因为多次糖基化可能会干扰GHb评估。使用天然质谱法推算出来自19%GHb样品的不同糖化血红蛋白的化学计量组成。我们观察到单糖化HbA0​​具有相当数量的α和β糖化四聚体。出奇,糖化的HbA0呈双倍和三倍,也显示出单糖化的α和β球蛋白。因此,我们提出血红蛋白(HbA)的糖基化对称地发生在α和β球蛋白之间,优先于未修饰的球蛋白。常规和基于质谱的GHb定量之间的相关性显示了对携带HbA0的个体的血糖指数的可靠估计。由于其表面电荷的差异,突变型HbA的保留时间与HbA0的保留时间不同。因此,与GHb相比,它们的糖化类似物可能在不同的保留时间洗脱。因此,我们的方法对于评估携带突变型HbA的个体的血糖指数将是理想的。常规和基于质谱的GHb定量之间的相关性显示了对携带HbA0的个体的血糖指数的可靠估计。由于其表面电荷的差异,突变型HbA的保留时间与HbA0的保留时间不同。因此,与GHb相比,它们的糖化类似物可能在不同的保留时间洗脱。因此,我们的方法对于评估携带突变型HbA的个体的血糖指数将是理想的。常规和基于质谱的GHb定量之间的相关性显示了对携带HbA0的个体的血糖指数的可靠估计。由于其表面电荷的差异,突变型HbA的保留时间与HbA0的保留时间不同。因此,与GHb相比,它们的糖化类似物可能在不同的保留时间洗脱。因此,我们的方法对于评估携带突变型HbA的个体的血糖指数将是理想的。
更新日期:2020-03-16
down
wechat
bug