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本文探讨了硒(Se)在血红蛋白(Hb)上的分布,以及摄硒量和摄硒形式对其分布的影响。结果表明,人体Hb中Se全部在珠蛋白上,且均匀分布于α和β链上;当硒蛋氨酸形式的硒摄入较多而在Hb中出现“富裕”硒时,在分离过程中有一部分硒会从Hb上脱落下来。这就提示Se与Hb之间至少存在紧密和松散的两种连接方式。 据α和β链中氨基酸的组成,我们推测,Se和Hb之间较紧密的连接是以硒蛋氨酸形式存在,它是膳食硒在Hb合成时掺入的;那松散的连接是有一部分“富裕”硒与半胱氨酸(CyS),特别是β链93位的CyS,连接形成不稳定的硒代三硫化物或硒过硫化物,它们在分离时很容易被还原脱落。一旦机体需要硒时,有可能首先动用这部分硒。
This article explored the distribution of selenium (Se) on hemoglobin (Hb) and its effect on the distribution of photogenic selenium and photogenic selenium. The results showed that Se in human Hb was all on globin and was uniformly distributed on the α and β chains. When selenomethionine forms more selenium and more abundant selenium appeared in Hb, part of the Se Selenium will fall off from Hb. This suggests that there is at least two tight and loose connections between Se and Hb. According to the composition of the amino acids in the alpha and beta chains, we speculate that the more tightly linked Se and Hb exist as selenomethionine, which is the dietary selenium incorporated during Hb synthesis; that loose connection is a part of “rich ”Selenium and Cystine (CyS), especially CyS at the β-chain at position 93, are linked to form unstable selenotri-sulfide or selenium-sulfide, which are easily reduced and detached when separated. Once the body needs selenium, it is possible to first use this part of selenium.