Transferrin（TF） and its isoforms have been widely reported via various analytical techniques, including a noticeable increased number of isoforms with low content of sialic acid（asialo-, monosialo-, and disialo-tra...Transferrin（TF） and its isoforms have been widely reported via various analytical techniques, including a noticeable increased number of isoforms with low content of sialic acid（asialo-, monosialo-, and disialo-transferrin） and asialo-TF as well as disialo-TF, with one or several oligosaccharides released in human serum transferrin（hTf）. Here, hTf has been purified by native gradient polyacrylamide gel electrophoresis（PAGEso） before use. The hTf extracted with the electron-transfer approach showed a single subunit band（77.1 Da） in the SDS-PAGE gel, but it exhibited two bands in the native and denatured isoelectric focusing（IEF） gels, namely, hTf-2Fe^3＋ and apo-hTf, without finding any other transferrin isoforms. A reversed phase HPLC（RP-HPLC） equipped with a C18 column effectively separated hTf and its polymers and combined off-line techniques, including peptide mass fingerprinting（PMF）, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDI-TOF-MS） and database search, and identified the high homology among hTf, apo-hTf, and their isoforms. Moreover, the elution solution consisting of acetonitrile and formic acid could easily denature both hTf and apo-hTf to form various isoforms during separation with HPLC, indicating that chemical factors lead to the formation of various isoforms in transferrin, artificially, during extraction and separation. The authors claimed that only two transferrin isoforms existed in the NHS, namely, hTf-2Fe^3＋ and apo-hTf, which could be employed in biomarkers, to distinguish the healthy population from many disease sufferers, such as, carbohydrate-deficient transferrin（CDT）展开更多
建立了一种从Cohn血浆分离副产物组分IV中纯化高纯度转铁蛋白（Tf）标准物质的技术,对Cohn组分IV进行复溶、离心和过滤,采用Capto DEAE阴离子交换色谱进行初分离,再通过穿透式Octyl-Sepharose 4 Fast Flow疏水色谱进一步精制;对纯化产...建立了一种从Cohn血浆分离副产物组分IV中纯化高纯度转铁蛋白（Tf）标准物质的技术,对Cohn组分IV进行复溶、离心和过滤,采用Capto DEAE阴离子交换色谱进行初分离,再通过穿透式Octyl-Sepharose 4 Fast Flow疏水色谱进一步精制;对纯化产品进行了结构、纯度、活性等表征,采用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳、基质辅助激光解吸电离飞行时间质谱、高效液相色谱及酶联免疫吸附法对Tf标准物质进行了分析.结果表明,Tf产品纯度大于99%,收率为79%;圆二色光谱分析显示Tf的二级结构未发生改变,铁离子结合能力实验表明Tf可结合2个铁离子,保持活性.展开更多
基金National Natural Science Foundation of China(No.30470372Foundation of Xiamen Natural Science of China(No.3502Z2001262)Program for Innovative Research Team in Science and Technology in Fujian Province University
文摘Transferrin（TF） and its isoforms have been widely reported via various analytical techniques, including a noticeable increased number of isoforms with low content of sialic acid（asialo-, monosialo-, and disialo-transferrin） and asialo-TF as well as disialo-TF, with one or several oligosaccharides released in human serum transferrin（hTf）. Here, hTf has been purified by native gradient polyacrylamide gel electrophoresis（PAGEso） before use. The hTf extracted with the electron-transfer approach showed a single subunit band（77.1 Da） in the SDS-PAGE gel, but it exhibited two bands in the native and denatured isoelectric focusing（IEF） gels, namely, hTf-2Fe^3＋ and apo-hTf, without finding any other transferrin isoforms. A reversed phase HPLC（RP-HPLC） equipped with a C18 column effectively separated hTf and its polymers and combined off-line techniques, including peptide mass fingerprinting（PMF）, matrix-assisted laser desorption/ionization time-of-flight mass spectrometry（MALDI-TOF-MS） and database search, and identified the high homology among hTf, apo-hTf, and their isoforms. Moreover, the elution solution consisting of acetonitrile and formic acid could easily denature both hTf and apo-hTf to form various isoforms during separation with HPLC, indicating that chemical factors lead to the formation of various isoforms in transferrin, artificially, during extraction and separation. The authors claimed that only two transferrin isoforms existed in the NHS, namely, hTf-2Fe^3＋ and apo-hTf, which could be employed in biomarkers, to distinguish the healthy population from many disease sufferers, such as, carbohydrate-deficient transferrin（CDT）
文摘建立了一种从Cohn血浆分离副产物组分IV中纯化高纯度转铁蛋白（Tf）标准物质的技术,对Cohn组分IV进行复溶、离心和过滤,采用Capto DEAE阴离子交换色谱进行初分离,再通过穿透式Octyl-Sepharose 4 Fast Flow疏水色谱进一步精制;对纯化产品进行了结构、纯度、活性等表征,采用十二烷基磺酸钠-聚丙烯酰胺凝胶电泳、基质辅助激光解吸电离飞行时间质谱、高效液相色谱及酶联免疫吸附法对Tf标准物质进行了分析.结果表明,Tf产品纯度大于99%,收率为79%;圆二色光谱分析显示Tf的二级结构未发生改变,铁离子结合能力实验表明Tf可结合2个铁离子,保持活性.
