河西走廊地区盐碱土壤微生物总DNA提取方法的比较

Comparison of Microbial Total DNA Extraction Methods from Saline-alkali Soils in Hexi Corridor

为了找出一种更适于河西走廊地区盐碱土壤微生物总DNA的提取方法,分别运用方法 1(Omega试剂盒法)、方法 2(Mo Bio试剂盒法)、方法 3(CTAB-SDS法)和方法 4(Ca Cl2-SDS-酶解法),对河西走廊盐碱土壤微生物总DNA的提取方法进行比较。4种方法所提取总DNA片段分子量大约在23.1 kb,完整性较好,无明显降解现象。但4种方法所提取DNA的量差异很大,其中方法 1和方法 2提取的DNA目的条带不清晰,但纯度较高;方法 3和方法 4所提取的DNA产量高于方法 1和方法 2,但方法 3提取的总DNA杂质较多,影响后续分析的准确性;而方法4所提取得DNA纯度基本与试剂盒法接近,DNA提取量可达到452.875μg·g-1,远远高于其他3种方法,能满足后续实验,是一种较理想的且适合于河西走廊盐碱土壤微生物多样性和种群结构的总DNA提取方法。

Due to soil microbial community structure and diversity and their change to a certain extent reflect the quality of the soil,the saline soil microbial diversity and population structure have certain application value for saline soil improvement. Saline soil is a special kind of soil type,may be a lot of salt resistance,alkali resistance and halophilic extremophiles groups,and has great development and utilization value,can build saline soil microbial macro gene pool,and screen out useful genetic resources used by mankind. To establish a method of total DNA extraction for investigation of the microbial population structure and diversity at saline-alkali soil in Hexi corridor,four kinds of methods that are M1（ Omega kit method）,M2（ Mo Bio kit method）,M3（ modified high-salt method） and M4（ Calcium chloride-SDS-Enzymatic） were used. The results showed that： 23. 1 kb DNA fragments were obtained by the methods,and no DNA degradation. But the DNA extraction results were very different between the 4 methods,M1 and M2 shows no clear bands but high pure DNA; M3 and M4 obtain higher DNA amount than M1 and M2,however,the DNA obtained by M3 has more impurities which affects the accuracy of subsequently analysis. The DNA purity by M4 are more approximate to the kit method,the amount of DNA extraction reached 452. 875 μg·g-1,much higher than the other 3 kinds of methods,more suitable for the subsequent experiments. The results indicated that M4 is suitable for total DNA extraction to study microbial abundance and diversity from saline-alkali soil in Hexi Corridor.