Pig pancreas ferritin（PPF） was purified by ultra-centrifugation, ion-exchange chromatography, and native gradient polyacrylamide gel electrophoresis（PAGENG）. Sodium dodecyl sulfate（SDS）-PAGE indicates that PPF c...Pig pancreas ferritin（PPF） was purified by ultra-centrifugation, ion-exchange chromatography, and native gradient polyacrylamide gel electrophoresis（PAGENG）. Sodium dodecyl sulfate（SDS）-PAGE indicates that PPF consists of two subunit types, namely, H（21000） and L（19000） subunits, and its core shows an average element composition of 1698 Fe3＋ and 179 phosphate molecules within the hollow shell, giving a 9.5：1 ratio of Fe3＋ to phosphate. An off line approach combining reversed-phase high-performance liquid chromatography（RP-HPLC） with matrix-assisted laser desorption ionization time of flight mass spectrometry（MALDI-TOF MS） made the decomposition of PPF shell into H and L subunits for the analysis of mass spectrometry（MS）, giving molecular weights of both H（21014.4） and L（18319.9） subunits. Both subunit types were further identified by an approach combining peptide mass fingerprint（PMF） with database search. A ratio of 1H to 2L subunits in PPF was determined by SDS-PAGE, RP-HPLC, and MALDI-TOF MS, respectively. It is well known that the non-covalent interaction of L-L or H-L subunits is stronger than that of H-H subunits in PPF, which may be further used to explain the unclear physiological function between H and L subunits in PPF.展开更多
小批量制备质谱纯魟鱼肝铁蛋白(liver ferritin of Dasyatis akajei,DALF),以透射电子显微镜术(TEM)测定DALF、蛋白壳和铁核的分子尺寸。SDS-PAGE技术指出,DALF由H和L两种不同类型的亚基组成。采用肽质量指纹图谱(PMF)技术进一步佐证H和...小批量制备质谱纯魟鱼肝铁蛋白(liver ferritin of Dasyatis akajei,DALF),以透射电子显微镜术(TEM)测定DALF、蛋白壳和铁核的分子尺寸。SDS-PAGE技术指出,DALF由H和L两种不同类型的亚基组成。采用肽质量指纹图谱(PMF)技术进一步佐证H和L亚基类型和同源性。氧化还原剂中性红、劳氏紫、甲基紫精和pH1.5酸度均无法削弱DALF的H-L和L-L亚基之间的相互作用强度、并解吸出L亚基离子,供MALDI-TOF质谱仪分析。通过增加激光强度和降低基质pH途径,可直接分析DALF的H和L亚基的分子量,指出DALF中H-L和L-L亚基之间的相互作用强度明显高于H-H亚基类型。展开更多
基金the National Natural Science Foundation of China(No.40776060)the Program for Innovative Research Team in Science and Technology in Fujian Province University.
文摘Pig pancreas ferritin（PPF） was purified by ultra-centrifugation, ion-exchange chromatography, and native gradient polyacrylamide gel electrophoresis（PAGENG）. Sodium dodecyl sulfate（SDS）-PAGE indicates that PPF consists of two subunit types, namely, H（21000） and L（19000） subunits, and its core shows an average element composition of 1698 Fe3＋ and 179 phosphate molecules within the hollow shell, giving a 9.5：1 ratio of Fe3＋ to phosphate. An off line approach combining reversed-phase high-performance liquid chromatography（RP-HPLC） with matrix-assisted laser desorption ionization time of flight mass spectrometry（MALDI-TOF MS） made the decomposition of PPF shell into H and L subunits for the analysis of mass spectrometry（MS）, giving molecular weights of both H（21014.4） and L（18319.9） subunits. Both subunit types were further identified by an approach combining peptide mass fingerprint（PMF） with database search. A ratio of 1H to 2L subunits in PPF was determined by SDS-PAGE, RP-HPLC, and MALDI-TOF MS, respectively. It is well known that the non-covalent interaction of L-L or H-L subunits is stronger than that of H-H subunits in PPF, which may be further used to explain the unclear physiological function between H and L subunits in PPF.
文摘小批量制备质谱纯魟鱼肝铁蛋白(liver ferritin of Dasyatis akajei,DALF),以透射电子显微镜术(TEM)测定DALF、蛋白壳和铁核的分子尺寸。SDS-PAGE技术指出,DALF由H和L两种不同类型的亚基组成。采用肽质量指纹图谱(PMF)技术进一步佐证H和L亚基类型和同源性。氧化还原剂中性红、劳氏紫、甲基紫精和pH1.5酸度均无法削弱DALF的H-L和L-L亚基之间的相互作用强度、并解吸出L亚基离子,供MALDI-TOF质谱仪分析。通过增加激光强度和降低基质pH途径,可直接分析DALF的H和L亚基的分子量,指出DALF中H-L和L-L亚基之间的相互作用强度明显高于H-H亚基类型。
