ADSORPTION OF DNA ON CLAY-MINERALS - PROTECTION AGAINST DNASEI AND INFLUENCE ON GENE-TRANSFER
ADSORPTION OF DNA ON CLAY-MINERALS - PROTECTION AGAINST DNASEI AND INFLUENCE ON GENE-TRANSFER
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DOI：
10.1111/j.1574-6968.1992.tb05435.x
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发表时间：
1992-10-01
影响因子：
2.1
通讯作者：
SIMONET, P
中科院分区：
文献类型：
--
作者：
PAGET, E;MONROZIER, LJ;SIMONET, P
许多作者研究了沙质土壤与DNA的关系。建立了蒙脱土吸附多种DNA的模型，用于测定粘土吸附的核酸上的酶(DNaseI)活性。DNA的吸附程度受所用阳离子(镁、钙、钠)的浓度和价态的影响，表明这是一个电荷依赖的过程。小牛胸腺DNA被蒙脱石(高达30mgg-1的干粘土)高度吸附。吸附的DNA比游离DNA更能抵抗DNaseI的降解。用质粒和短线性扩增(通过聚合酶链式反应)DNA的实验数据表明，对核酸酶的保护作用只是部分的。然而，研究发现，黏土吸附的DNA即使在经过强烈的DNaseI处理后，仍然能够人工转化感受态的大肠杆菌细胞。结果表明，土壤中可能存在DNA的持久性和遗传转化的基因转移。
Numerous authors have investigated DNA relationships with sandy soil. A model composed of various DNAs adsorbed on montmorillonite clay was developed to assay enzyme (DNaseI) activity on clay-adsorbed nucleic acids. The extent of DNA adsorption was affected by the concentration and valency of the cations used (Mg2+, Ca2+, Na+), indicating a charge-dependent process. Calf thymus DNA was found to be highly adsorbed by smectite (up to 30 mg g-1 of dry clay). Adsorbed DNA was shown to be more resistant to degradation by DNaseI than free DNA. Experimental data with plasmid and short linear amplified (through polymerase chain reaction) DNA showed that protection against nucleases was only partial. Nevertheless, clay-adsorbed DNA was found to be still able, even after a strong DNaseI treatment, to artificially transform competent Escherichia coli cells. The results show that persistance of DNA and gene transfer by genetic transformation may occur in soil.