Toxicity of Cobalt and Nickel to Salmon Sperm's DNA and the Antagonistic Effect of Magnesium and Copper

The aim of present study is to investigate the damage to salmon sperm DNA caused by Ni²⁺ and Co²⁺ ions and how they interact with Cu²⁺ and Mg²⁺ ions using fluorescent spectrometry. The results reveal that both Ni²⁺ and Co²⁺ ions damage salmon sperm DNA due to the binding of Ni²⁺ and Co²⁺ ions with DNA double strand. We can observe that the fluorescent intensity of DNA turns stronger and the corresponding wavelength becomes longer suggesting that the hypereffect and bathochromic shift occurred, both of which can be regarded as symbols of DNA denaturing. Compared to that observed in the DNA‐Ni²⁺/Co²⁺ complex, Cu²⁺ and Mg²⁺ ions have a less damage to DNA. The ability of Ni²⁺ or Co²⁺ ions binding to DNA will be inhibited by Cu²⁺ and Mg²⁺ ions, respectively, as they will compete for the binding site in the double strand, which can be proved by the decreasing of fluorescent intensity and the wavelength of DNA‐ Ni²⁺ or DNA‐Co²⁺ complex in the presence of Cu²⁺ and Mg²⁺ ions.

Keywords:

• Salmon sperm DNA
• toxicity
• antagonistic effect
• fluorescent spectrometry

Thanks to the Halobios laboratory for Jiangsu province (2005HS008), funding from for Huai Hai Institute of Technology (KK01062).