Stabilization of nucleic acids by unusual polyamines produced by an extreme thermophile, Thermus thermophilus
Stabilization of nucleic acids by unusual polyamines produced by an extreme thermophile, Thermus thermophilus
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DOI：
10.1042/bj20041778
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发表时间：
2005-06-01
影响因子：
4.1
通讯作者：
Oshima, T
中科院分区：
文献类型：
--
作者：
Terui, Y;Ohnuma, M;Oshima, T
极端嗜热菌产生两种类型的不寻常多胺：长线性多胺，例如caldopentainine和caldohexamine，以及支链多胺，例如季铵化合物[例如季铵化合物]。四(3-氨基丙基)铵]。为了阐明长直链和支链多胺在嗜热菌中的生理作用，我们对它们进行了化学合成，并测试了它们对 ds（双链）和 ss（单链）DNA 和 tRNA 响应热变性的稳定性的影响，通过差示扫描量热法测量。线性多胺按照其分子结构中氨基氮原子的数量成比例地稳定双链 DNA。我们利用经验结果推导了估算特定分子组成的多胺存在下双链 DNA 熔解温度的公式。四（3-氨基丙基）铵比任何其他测试的多胺更有效地稳定 ssDNA 和 tRNA。我们认为，长线性多胺可有效稳定 DNA，而四（3-氨基丙基）铵在稳定嗜热细胞中的 RNA 方面发挥着重要作用。
Extreme ther-mophiles produce two types of unusual polyamine: long linear polvarnines such as caldopentainine and caldohexamine, and branched polyamines such as quaternary ammonium compounds [e.g. tetrakis(3-aminopropyl)ammonium]. To clarify the physiological roles of long linear and branched polyamines in thermophiles, we synthesized them chemically and tested their effects on the stability of ds (double-stranded) and ss (single-stranded) DNAs and tRNA in response to thermal denaturation, as measured by differential scanning calorimetry. Linear polyamines stabilized dsDNA in proportion to the number of amino nitrogen atoms within their molecular Structure. We used the empirical results to derive formulae that estimate the melting temperature of dsDNA in the presence of polyamines of a particular molecular composition. ssDNA and tRNA were stabilized more effectively by tetrakis(3-aminopropyl)ammonium than any of the other polyamines tested. We propose that long linear polyamines are effective to stabilize DNA, and tetrakis(3-amino-propyl)ammonium plays important roles in stabilizing RNAs in thermophile cells.