In vivo substitution of zinc by cobalt in carbonic anhydrase of a marine diatom
In vivo substitution of zinc by cobalt in carbonic anhydrase of a marine diatom
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海洋硅藻碳酸酐酶中钴在体内取代锌
DOI：
10.4319/lo.1996.41.3.0573
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发表时间：
1996
影响因子：
4.5
通讯作者：
F. Morel
中科院分区：
文献类型：
--
作者：
D. Yee;F. Morel
我们研究的机制，其中钴添加部分减轻海洋硅藻在低锌浓度的文化中的生长限制。培养的沿海硅藻海链藻weissfloclavis生长在低锌条件下，并提供了低和高水平的公司。酶测定和放射自显影电泳凝胶的细胞蛋白质显示，大部分的钴被发现在主要亚型的酶碳酸酐酶（CA），其中大部分的锌位于。CA对Co的亲和力低于对Zn的亲和力，并且Co取代的酶的活性低于天然Zn形式。不同CO2分压下的生长比较表明，Co可以改善碳限制培养物的生长。我们的结论是，钴通过直接取代CA，这是重要的碳收购锌限制。
We examined the mechanism by which Co additions partially alleviate the growth limitation of marine diatoms in cultures with low Zn concentrations. Cultures of the coastal diatom Thalassiosira weissflogii were grown under low-Zn conditions and provided with low and high levels of Co. Enzyme assays and autoradiographs of electrophoresis gels of cellular proteins revealed that a large fraction of the Co is found in the main isoform of the enzyme carbonic anhydrase (CA), where most of the Zn is located. The affinity of CA for Co is lower than for Zn, and the Co-substituted enzyme is less active than the native Zn form. Comparisons of growth under different partial pressures of CO2 show that Co can ameliorate the growth of carbon-limited cultures. We conclude that Co alleviates Zn limitation via direct substitution in CA, which is important for carbon acquisition.