一种从重组质粒快速提纯DNA插入片段的方法

本文介绍一种从重组质粒中快速提纯ＤＮＡ插入片段的方法。质粒ＤＮＡ的制备简单、快速、分离的质粒ＤＮＡ可用于限制性酶切和转化大肠杆菌等。从琼脂糖凝胶中提纯ＤＮＡ插入片段的方法操作简单,回收效率高,提纯的ＤＮＡ片段可用于连接和制备杂交探针等。     

一种从酵母菌转化子中分离,检测重组质粒的有效方法

本文介绍了一种从酵母转化子中分离、检测重组质粒的有效方法。从小量酵母培养物提取的ＤＮＡ可有效地转化大肠杆菌,转化效率大约为３．７×１０５转化子／ｕｇＤＮＡ     

质粒pcDNA3—HGF的大规模纯经制备研究

质粒ｐｃＤＮＡ３－ＨＧＦ具有潜在的临床治疗缺血性疾病的应用前景。大规模纯化制备是质粒ＤＮＡ应用于基因治疗的关键步骤。质粒大规模纯化制备流程包括：发酵、离心收集细胞、碱性裂解、Ｑ－Ｓｅｐｈａｒｏｓｅ ＸＬ捕获质粒ＤＮＡ、Ｓｏｕｒｃｅ １５Ｑ精制质粒ＤＮＡ,所得纯超螺旋质粒ｐｃＤＮＡ３－ＨＧＦ符合质量标准。该纯化制备方法避免使用动物源性的酶及有毒试剂。     

链霉菌—大肠菌穿梭质袜载体pSGLgpp的构建及应用

质粒ｐＳＧＬ１（７．４ｋｂ）是从球孢链霉菌（Ｓｔｒｅｐｔｏｍｙｃｅｓ ｇｅｏｂｉｓｐｏｒｕｓ）中分离得到的一个高拷贝质粒,已测定其最小复制子序列。从球孢链霉菌总ＤＮＡ中采用ＰＣＲ方法扩增获得编码Ｃ１０２７前蛋白信号肽的ＤＮＡ片断ｇｐｐ。将ｇｐｐ克隆至ｐＳＧＬ１的衍生质粒ｐＳＧＬＮ中,获得新的链霉菌表达型质粒载体ｐＳＧＬｇｐｐ。应用该质粒进行了人的河溶性白细胞介素１受体Ｉ型的表达。     

离子交换树脂法与酚仿法对质粒DNA提取效果的比较

通过两种不同方法对质粒ＤＮＡ提取效果的比较,证实了阴离子交换树脂法能够获得高纯度的质粒ＤＮＡ,满足分子生物学的试验要求,操作简便、快速,不污染实验室的环境,是一种较理想的制备高纯度质粒ＤＮＡ的提取方法。     

一种高纯度、高得率的质粒DNA纯化法

一种高纯度、高得率的质粒ＤＮＡ纯化法汤乃梅,王晓民,韩济生（北京医科大学神经科学研究中心,北京１０００８３）关键词质粒ＤＮＡ纯化本文介绍一种方法,它不仅可以得到高纯度质粒ＤＮＡ,而且在同等纯度下的得率也高于其它方法,其操作流程如下：１．５００ｍｌ菌液...     

彻底清除转化体中野生型DNA的专一位点诱变方法

我们设计了一种高效的专一位点诱变方法,可从混合体中清除野生型ＤＮＡ。并将所需突变ＤＮＡ转入被转化细胞中,如此合成了与一种ＤＮＡ分子目标序列一致的并带有能产生限制性内切酶位点的插入突变的两条互补的寡核苷酸链。利用野生型ＤＮＡ分子中的两端各有两个限制性位点的一段目标ＤＮＡ片段作为模板,上述合成的两种寡核苷酸引物被延伸、富集并分离。被延伸的产物在聚合酶链式反应中又反过来被用作模板,以获得突变的双链ＤＮＡ片段,此片段通过其两端的限制性位点能很方便地用侧面限制性内切位点克隆到质粒中去。用这些质粒转化的大肠杆菌（Ｅｓｃｈｅｒｉｃｈｉａｃｏｌｉ）细胞可进行大量的分析。通过集落杂交试验、限制性内切酶分析和ＤＮＡ序列分析,得知这些转化体百分之百含有突变型的ＤＮＡ序列。     

紫色非硫细菌质粒的制备与性质

介绍一种适于紫色非硫细菌质粒的制备方法,该法简单,易操作,质粒ＤＮＡ纯度好,收率高,通过在加富培养基上连续传代数次,质粒ＤＮＡ可自行消除。     

簇毛麦低拷贝cDNA序列的克隆和鉴定

从簇毛麦叶片中提取总ＲＮＡ,进一步分离ｍＲＮＡ。以ｍＲＮＡ为模板反转录合成ｃＤＮＡ,两端经Ｔ４ＤＮＡ多聚酶修平后加ＥｃｏＲ１接头分子,连接于质粒ｐＧＥＭ－７Ｚｆ（＋）的ＥｃｏＲ１克隆位点,转化大肠杆菌ＪＭ１０３菌株建立了ｃＤＮＡ文库。用ＰＣＲ扩增重组质粒的ｃＤＮＡ插入序列,用＾３２Ｐ标记后分别与ＨｉｎｄⅢ或ＸｂａⅠ酶切的小麦－黑麦附加系ＤＮＡ进行Ｓｏｕｔｈｅｒｎ杂交。根据其杂交结果,目前已鉴定出４     

鸡马立克氏病病毒B抗原片段在大肠杆菌中表达

鸡马立克氏病病毒ＢａｍＨＩ基因文库Ｉ３质粒中含有编码Ｂ抗原膜外Ｄｏｍａｉｎ的ＤＮＡ序列。经ＳｃａＩ和ＳｐｈＩ双酶酶解Ｉ３质粒,分离获得７６４ｂｐＤＮＡ片段,并克隆进Ｍ１３ｍｐ１９中。ＤＮＡ序列测定分析表明克隆片段为ＭＤＶ－Ｂ抗原基因的４９４－１２５８ｂｐ部分序列。进一步分离ＮｃｏＩ－ＨｉｎｄＩＩＩ部分基因片（５３０ｂｐ）,克隆于ＰＬＰｒｏｍｏｔｅｒ控制下的含有修饰型ｃＩｔｓ８５７基因的表达载体中,     

An efficient purification and fractionation of genomic DNA from soil by modified troughing method

AIMS: The aim of this study was to utilize a modified troughing method for purification of large genomic DNA obtained from microbiota in natural environment and for fractionation of genomic DNA into many size ranges that facilitates construction of metagenomic library. METHODS AND RESULTS: Genomic DNA extracted from soil or termite gut was purified by the modified troughing method which utilized gel electrophoresis in the presence of 30% PEG8000. The method performed better than various purification kits and allowed no significant loss in the amount of DNA recovered. In addition, the efficiency of the modified troughing method for DNA size fractionation was investigated. DNA size fractionation was achieved with repetitive rounds of electrophoresis and DNA collection to obtain DNA with many size ranges. CONCLUSIONS: The modified troughing method is a simple and efficient method for purification of genomic DNA and for DNA size fractionation. SIGNIFICANCE AND IMPACT OF THE STUDY: The modified troughing method is a straightforward and inexpensive technique readily available for anyone working with environmental genomic DNA. It facilitates cloning of genomic DNA and enhances rapid discovery of useful bioactive compounds from microbial resources.     

4种黑曲霉基因组DNA提取方法的比较

目的:筛选适合提取曲霉DNA的方法.方法:比较2个菌落培养时间段(3d内和10d左右)提取DNA质量的差异;运用氯化苄法、石英砂+CTAB法、Biospin法和微波法分别提取黑曲霉基因组DNA,然后用直接电泳、浓度测定、PCR扩增等方法比较所提DNA的浓度和质量.结果:培养3d内的菌落提取的DNA纯度较高,无需纯化即可用于后续实验;4种方法制备的DNA均可用于PCR等后续实验,其中以石英砂+CTAB法提取的DNA纯度好,产率最高.结论石英砂+CTAB法是一种适用于曲霉DNA提取的简便方法.     

三种人全血基因组DNA提取方法的比较

目的：比较改良酚一氯仿抽提法、盐析法、试剂盒法从人全血中提取基因组DNA的效果,以期建立一种快速、经济的提取高质量基因组DNA的方法。方法：分别用上述三种方法从人全血中提取基因组DNA,通过紫外分光光度计、琼脂糖凝胶电泳、聚合酶链式反应（PCR）、限制性内切酶酶切检测提取的基因组DNA的产量、纯度和质量。结果：改良酚一氯仿抽提法与试剂盒法提取的基因组DNA相比,DNA的产量有统计学差异,DNA的纯度无统计学差异,但试剂盒法提取的基因组DNA有较明显的降解现象：盐析法与改良酚．氯仿抽提法、试剂盒法相比,基因组DNA的产量和纯度都存在统计学差异,并且基因组DNA聚合酶链式反应（PCR）扩增的稳定性也明显劣于另外两种方法;三种方法提取基因组DNA均能进行限制性内切核酸消化。结论：改良酚一氯仿抽据取法是一种经济、快速、高效、稳定提取人全血基因组DNA的方法,适用于批量临床标本处理。     

苛求芽孢杆菌基因组DNA提取方法的比较

目的:比较不同方法提取苛求芽孢杆菌基因组DNA的差异。方法:用经典CTAB提取法、改进CTAB法(溶菌酶处理结合CTAB提取法)、UniQ柱吸附提取法制备苛求芽孢杆菌基因组DNA,比较产物完整性和用于PCR扩增的有效性。结果:三种方法制备基因组DNA纯度接近,但改进CTAB法产率最高,UniQ法产率最低。经典CTAB法和UniQ法提取基因组DNA易降解。三种方法所得基因组DNA用于PCR扩增效率接近。结论:溶菌酶裂解结合CTAB提取更适合制备苛求芽孢杆菌基因组DNA。     

Recycling Isolation of Plant DNA,A Novel Method

DNA is one of the most basic and essential genetic materials in the field of molecular biology.To date,isolation of sufficient and good-quality DNA is still a challenge for many plant species,though various DNA extraction methods have been published.In the present paper,a recycling DNA extraction method was proposed.The key step of this method was that a single plant tissue sample was recycled for DNA extraction for up to four times,and correspondingly four DNA precipitations(termed as the 1st,2nd,3rd and 4th DNA sample, respectively) were conducted.This recycling step was integrated into the conventional CTAB DNA extraction method to establish a recycling CTAB method.This modified CTAB method was tested in eight plant species,wheat,sorghum,barley,corn,rice,Brachypodium distachyon,Miscanthus sinensis and tung tree.The results showed that high-yield and good-quality DNA samples could be obtained by using this new method in all the eight plant species.The DNA samples were good templates for PCR amplification of both ISSR and SSR markers.The recycling method can be used in multiple plant species and can be integrated with multiple conventional DNA isolation methods,and thus is an effective and universal DNA isolation method.     

Comparison of three common DNA concentration measurement methods

Accurate measurement of DNA concentration is important for DNA-based biological applications. DNA concentration is usually determined by the ultraviolet (UV) absorption, fluorescence staining, and diphenylamine reaction methods. However, the best method for quality assurance of measurements is unknown. Here, we comprehensively compared these methods using different types of samples. We found that all three methods accurately determined the concentrations of high-purity DNA solutions. After digestion of DNA samples, concentration measurements revealed that the PicoGreen dye method was very sensitive to the degradation of DNA. The three methods displayed different anti-jamming ability when contaminants such as transfer RNA (tRNA), protein, and organic chemicals were included in DNA solutions. The diphenylamine reaction method gave the highest accuracy, with an average error of approximately 10% between measured and true values. The PicoGreen dye method was influenced by tRNA and protein, and the UV absorption method was susceptible to all kinds of impurities. Overall, the diphenylamine reaction method gave the most accurate results when DNA was mixed with contaminants, the PicoGreen dye method was most suitable for degraded DNA samples or DNA extracted from processed products, and the UV absorbance method was best for evaluating the impurities in DNA solutions.     

鸡肠道菌群总DNA三种提取方法的比较

目的比较不同方法提取鸡肠道菌群总DNA的差异,为分子方法分析肠道菌群组成提供质量较高的DNA模板。方法采用反复冻融法、酶裂解法和试剂盒法（E.N.Z.A Stool DNA Kit）来提取鸡肠道菌群的总DNA,并根据DNA浓度及纯度、16S DNA扩增产物和ERIC-PCR产物所反映的片段多态性4个指标,对这3种方法提取的DNA质量进行比较。结果3种方法均能提取DNA,所得DNA都可以用于16S DNA的扩增,但后2种方法所得DNA的ERIC-PCR结果能反映出更高的菌群多样性。结论试剂盒法和酶裂解法所提取的DNA质量好,适合用于肠道菌群的分子生态研究。     

High yield DNA extraction from the snake cast-off skin or bird feathers using collagenase

A simple method to extract DNA in high yield from the snake cast-off skin or bird feathers was developed. The molecular weight of the extracted DNA was higher by this than the conventional method and the yield of DNA was increased by more than one hundred fold. The DNA extracted by this method could be used for PCR and other analyses. This method could be applied to various samples, for instance, extracting DNA from bird feather in general.     

适于涡虫基因组DNA快速制备的改良的CTAB法

提取得到高质量的DNA样品是进行分子生物学研究的必要前提。为了找到一种适用于提取涡虫基因组DNA的常规方法,我们以东亚三角头涡虫为材料,分别用改良的CTAB法、SDS法、SDS-蛋白酶K法对涡虫的基因组DNA进行了制备,并对3种方法制备的涡虫基因组DNA进行了检测与比较。根据比较结果,我们认为改良的CTAB法最适合于涡虫基因组DNA的快速制备,为涡虫的分子生物学研究打下了基础。     

苔藓植物DNA提取方法研究

提取高质量的 DNA是对苔藓植物遗传多样性进行研究的基础。该文以苔藓植物为试材 ,用 5种方法 ,即快速提取法、改良 CTAB法、CTAB法、SDS法及高盐法 (第一种为自行设计 ,第二种是对原有方法的改进 )对苔藓植物 DNA提取方法进行了比较研究。结果表明 ,快速提取法和改良 CTAB法是 2种适合于苔藓植物 DNA提取的方法。这 2种方法提取的 DNA浓度和纯度均比较高 ,凝胶电泳显示无明显降解现象 ,适宜作为 PCR扩增的模板 ,并成功地进行了 RAPD扩增。