Marques H M
Department of Chemistry, University of the Witwatersrand, Johannesburg, South Africa.
J Inorg Biochem. 1991 Feb 15;41(3):187-93. doi: 10.1016/0162-0134(91)80011-6.
The kinetics of release of Al3+ from human serum dialuminum transferrin (Al2Tf) to citrate were investigated at 37 degrees C, pH 7.4, mu = 0.7 M, by difference UV spectrophotometry. The two metal-binding sites are not identical but behave in a kinetically similar manner to give apparent second-order rate constants of 0.60 and 0.38 M-1 s-1, respectively, for release of the first Al3+ from Al2Tf. The rate constants for release of the second metal ion from the monoaluminum transferrins are 0.27 and 0.12 M-1 s-1. The kinetic scheme for release of A13+ from Al2Tf is therefore similar to that for release of Fe3+ from Fe2Tf, but the rate of constants for metal ion release are between two and four orders of magnitude larger.
通过差示紫外分光光度法，在37℃、pH 7.4、μ = 0.7 M的条件下，研究了人血清双铝转铁蛋白（Al2Tf）中Al3+向柠檬酸盐的释放动力学。两个金属结合位点并不相同，但在动力学上表现出相似的行为，从Al2Tf释放第一个Al3+时，表观二级速率常数分别为0.60和0.38 M-1 s-1。从单铝转铁蛋白释放第二个金属离子的速率常数分别为0.27和0.12 M-1 s-1。因此，Al2Tf中Al3+的释放动力学方案与Fe2Tf中Fe3+的释放动力学方案相似，但金属离子释放的速率常数要大两到四个数量级。
