The Zinc Specificity and Affinity of Zinc Binding Substance(s)in the Nuclei/Cell Debris Fraction of Digestive Tract Tissue of Common Carp, Cyprinus carpio
| Autor: | Ming-Shyong Wang, 王明雄 |
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| Rok vydání: | 1999 |
| Druh dokumentu: | 學位論文 ; thesis |
| Popis: | 87 Zinc concentrations in most tissues of animals and fishes were around 10~50 ppm; however, those in the digestive tract tissue of common carp were found to be extraordinarily high, being 300-500 ppm. It is also known that the nuclei/cell debris fraction was the major fraction responsible for these high concentration of zinc. In order to survey the specificity and affinity of zinc binding substance(s) in the digestive tissue of common carp, 65Zn was added to the Debris Fraction. Binding increased linearly with increase amounts of 65Zn. The Debris Fraction in the digestive tract tissue of common carp showed specific, saturable binding with 65Zn. Binding of 65Zn to Debris Fraction is fast and reversible. Other metal ions (including Fe, Cu, Mn, Mg, Ca, Ni, Hg, Cd and Co) all fail to displace zinc at 0.06 mM concentration. These attributes are consistent with the presence of “specific zinc binding substance(s)” in the digestive tract tissue of common carp. The specific binding of 65Zn and Debris Fraction is eliminated by protease treatment. Saturation analyses of the binding of 65Zn to digestive tract tissue Debris Fraction of common carp, and Scatchard plot for each saturation analysis were presented. The Kd and Nmax of zinc specific binding protein of common carp derived from these plot were 0.55~8.06 M and 0.14~ 2.35 nmol/g fresh tissue respectively. Therefore, it is concluded that there is a zinc specific binding protein existed in the Debris Fraction of digestive tract tissue of common carp. The saturation analyses of the binding of 65Zn to the digestive tract tissue Debris Fraction of of grass carp, silver carp and tilapia were also performed. It was found that in these fishes, there were also existed the zinc specific binding protein with Kd of 0.12~ 0.78 M. But Nmax of these fishes were 3 to 16 times lower than that of common carp. Obviously the reason why common carp has higher zinc concentration in its digestive tract tissue is due its higher concentration of the zinc specific binding protein. |
| Databáze: | Networked Digital Library of Theses & Dissertations |
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