大草履虫总DNA的提取方法比较

快速而稳定地提取大草履虫的基因组DNA是进行后续分子生物学研究的前提.文章通过比较传统SDS法、CTABⅠ法和CTABⅡ法等提取大草履虫DNA的效果,进一步优化提取方法,获得快速稳定地提取大草履虫基因组DNA的方法.结果表明:用CTAB I法提取的DNA浓度低,杂质较多;CTABII提取的DNA电泳时检测不出条带;而SDS法提取的DNA在电泳时带型较整齐,无降解,且DNA的得率和纯度较高,但仍有蛋白质污染.针对蛋白质的去除,用SDS-蛋白酶K法和SDS-NaAc法来提取DNA,经过试验发现这2种方法都能够很好地去除蛋白质,所获DNA样品的纯度和得率都能用于进一步分子试验,而SDS-NaAc法更经济适用.

Comparation of DNA Extraction Methods of Paramecium Caudatum

Isolation of genomic DNA is the precondition for molecular research on Paramecium caudatum. Traditional SDS method,CTABⅠmethod and CTABⅡmethod were employed to extract the genomic DNA from P. caudatum,Based on the experimental results,an optimized extraction procedure was established. The results showed that the DNA extracted by CTAB I method was poor in both purity and yield. The DNA extracted by CTABⅡ method was even undetectable,and the DNA extracted by the traditional SDS method performed better in yield and purity,but there were also protein impurities in DNA samples. In order to remove protein impurities,proteinase K and NaAc were separately added to treat the DNA samples extracted by the traditional SDS method. These two reagents could effectively remove protein impurities,and the yielded DNA could satisfy the requirements of molecular research in both purity and yield. Considering the experimental cost,the SDS-NaAc method was more economical and can be used to extract the genomic DNA from P. caudatum.