Keung W M, Azari P
J Biol Chem. 1982 Feb 10;257(3):1184-8.
The iron-transferring activity of iron-binding fragments FeNF and FeCF, representing the NH2- and CO2H-terminal domains of iron-ovotransferrin (Fe2OT), with a chicken embryo red cell system, was investigated. Each fragment is able to deliver iron to a chicken embryo red cell system for the biosynthesis of heme, FeNF being 44% more efficient than FeCF. The Fe fragments are on an average approximately 2 times less effective in delivering iron to the chicken embryo red cell than Fe2OT. The binding of FeNF and FeCF to CERC is essentially identical in terms of apparent association constant (K = 1.5 X 10(6) M-1, with respect to fragments) and the number of binding sites per cell at equilibrium (n = 2.9 X 10(4)); however, they differ significantly in their rates of delivering iron for heme synthesis.
利用鸡胚红细胞系统，研究了代表铁转铁蛋白（Fe2OT）的NH2和CO2H末端结构域的铁结合片段FeNF和FeCF的铁转运活性。每个片段都能够将铁输送到鸡胚红细胞系统中用于血红素的生物合成，FeNF的效率比FeCF高44%。Fe片段将铁输送到鸡胚红细胞的效率平均比Fe2OT低约2倍。就表观缔合常数（相对于片段，K = 1.5×10⁶ M⁻¹）和平衡时每个细胞的结合位点数（n = 2.9×10⁴）而言，FeNF和FeCF与鸡胚红细胞（CERC）的结合基本相同；然而，它们在为血红素合成输送铁的速率上有显著差异。
