Capillary isoelectric focusing-electrospray ionization mass spectrometry for transferrin glycoforms analysis
Capillary isoelectric focusing-electrospray ionization mass spectrometry for transferrin glycoforms analysis
复制标题
DOI：
10.1006/abio.1996.0492
复制
发表时间：
1996-12-01
影响因子：
2.9
通讯作者：
Lee, CS
中科院分区：
文献类型：
--
作者：
Yang, LY;Tang, Q;Lee, CS
采用毛细管等电聚焦（CIEF）-电喷雾电离质谱（ESIMS）技术对牛血清脱铁转铁蛋白糖型进行了高分辨分析。基于它们在等电点（pi）上的差异，在CIEF中分离和解析二唾液酸转铁蛋白、三唾液酸转铁蛋白和四唾液酸转铁蛋白。通过结合重力与阴极动员来洗脱二-、三-和四唾液酸转铁蛋白的聚焦蛋白质区。在CIEF毛细管的末端，通过与具有同轴鞘流配置的电喷雾接口在线耦合的质谱法分析动员的转铁蛋白区。在二-、三-和四唾液酸转铁蛋白中的每一种内的分子量不同的另外的转铁蛋白变体容易通过ESIMS区分。结合唾液酸酶消化，从CIEFESWIS测量获得无唾液酸转铁蛋白、单唾液酸转铁蛋白、二唾液酸转铁蛋白、三唾液酸转铁蛋白和四唾液酸转铁蛋白变体的pi分布和分子量。除了唾液酸数量的差异外，牛血清脱铁转铁蛋白聚糖的微观异质性可能因部分岩藻糖基化结构和α-Man-（1-6）天线上的α-Gal（1-3）-β-Gal而复杂化。(C)出版社：Academic Press，Inc.
On-line capillary isoelectric focusing (CIEF)-electrospray ionization mass spectrometry (ESIMS) as a two-dimensional separation system is employed for high-resolution analysis of bovine serum apotransferrin glycoforms. On the basis of their differences in isoelectric point (pi), the di-, tri-, and tetrasialotransferrins are separated and resolved in CIEF. The focused protein zones of di-, tri-, and tetrasialotransferrins are eluted by combining gravity with cathodic mobilization. At the end of CIEF capillary, the mobilized transferrin zones are analyzed by mass spectrometry coupled on-line to an electrospray interface with a coaxial sheath flow configuration. Additional transferrin variants within each of di-, tri-, and tetrasialotransferrins, differing in their molecular weights, are easily distinguished by ESIMS. In combination with sialidase digestion, the distribution of pi and molecular weight of asialo-, mono-, di-, tri-, and tetrasialotransferrin variants was obtained from the CIEFESWIS measurements. In addition to the differences in the number of sialic acid, the microheterogeneity of bovine serum apotransferrin glycans might be complicated by the partial fucosylated structure and the alpha-Gal (1-3)-beta-Gal on the alpha-Man-(1-6) antenna. (C) 1996 Academic Press, Inc.