A rapid method for extracting DNA from agarose gels

A method for obtaining high recovery of deoxyribonucleic acid (DNA) from agarose gels using an agarase extraction procedure is presented. This DNA is physically intact and biologically active. The DNA obtained with this procedure should be useful for a wide range of applications.     

适于RAPD分析的真菌DNA提取方法

报道一种高纯度、高分子量真菌基因组DNA的快速小量提取方法。该法制备的DNA降解少,分子量均在48.5kb以上;纯度高,所有样品的A260/280都在1.7-2.0之间;产率也很高,一般从500mg干菌丝可稳定获得530μg的DNA。所获得的DNA适用于RAPD分析。     

A rapid and efficient assay for extracting DNA from fungi

AIMS: A method for the rapid extraction of fungal DNA from small quantities of tissue in a batch-processing format was investigated. METHODS AND RESULTS: Tissue (< 3.0 mg) was scraped from freshly-grown fungal isolates. The tissue was suspended in buffer AP1 and subjected to seven rounds of freeze/thaw using a crushed dry ice/ethanol bath and a boiling water bath. After a 30 min boiling step, the tissue was quickly ground against the wall of the microfuge tube using a sterile pipette tip. The Qiagen DNeasy Plant Tissue Kit protocol was then used to purify the DNA for PCR/sequencing applications. CONCLUSIONS: The method allowed batch DNA extraction from multiple fungal isolates using a simple yet rapid and reliable assay. SIGNIFICANCE AND IMPACT OF THE STUDY: Use of this assay will allow researchers to obtain DNA from fungi quickly for use in molecular assays that previously required specialized instrumentation, was time-consuming or was not conducive to batch processing.     

A rapid method for determination of viable sulphate-reducing bacteria in human faeces

Adenosine phosphosulphate reductase (APS reductase) (E.C.1.8.99.2), viable counts of sulphate-reducing bacteria and rates of sulphate reduction were determined in 20 human samples of faeces. The activity of APS reductase, in contrast to sulphate reduction rates, correlated well with viable counts ( r = 0.987) and may therefore be used rapidly to quantify sulphate-reducing bacteria in human gut contents.     

一种冬虫夏草全基因组DNA的提取方法

冬虫夏草是真菌与昆虫形成的复合生物体,本研究建立了一种可同时提取冬虫夏草真菌子座和虫体全部基因组DNA的方法。该方法稳定高效,简便易行,提取纯度高,适用于冬虫夏草多重PCR、Realtime-PCR和DNA指纹图谱等分子水平的研究。     

A cheap,reliable and rapid method of extracting high‐quality DNA from plants

Here we describe a rapid method for extracting DNA from plant material using a microtitre plate system. This extraction procedure has been tested using three species, Brassica napus, Brassica napus/rapa hybrids and Arum maculatum, stored frozen, in silica gel or used fresh. The length of storage was between 7 days and 2 years, and in all cases high molecular weight DNA was reliably purified. Polymerase chain reaction (PCR) testing, using multiplex and single product amplification, inter simple sequence repeats (ISSRs) and microsatellites, was always reliable. This method combines the speed of commercial 96‐well plate methods with the economies associated with readily available laboratory chemicals.     

A rapid and simple method for extracting intracellular metabolites from Escherichia coli bacteria

The article deals with the development of a new method for the extraction of intracellular glycolytic metabolites from bacterial cells. The study has been made on the culture of E. coli B/r CSH. In accordance with this method, the same bacterial filter is used for both filtration (the removal of the culture fluid) and the extraction of low-molecular components of the cells with perchloric acid. The advantage of this method is the absence of unnecessary operations due to the use of a filter installation designed by the author. Quantitatively, this method yields better and reproducible results. The filtration capacity of different types of filters has been analyzed. The optimal time for the extraction of low-molecular cell components has been determined. A change in the concentration of pyruvate in the process of the cellular cycle of E. coli synchronous culture grown in the presence of glucose has been shown to occur. The newly developed method of extraction can be used not only for E. coli, but also for cells of other types.     

A rapid chemiluminescent method for quantitation of human DNA.

A sensitive and simple method for the quantitation of human DNA is described. This method is based on probe hybridization to a human alpha satellite locus, D17Z1. The biotinylated probe is hybridized to sample DNA immobilized on nylon membrane. The subsequent binding of streptavidin-horseradish peroxidase to the bound probe allows for chemiluminescent detection using a luminol-based reagent and X-ray film. Less than 150 pg of human DNA can easily be detected with a 15 minute exposure. The entire procedure can be performed in 1.5 hours. Microgram quantities of nonhuman DNA have been tested and the results indicate very high specificity for human DNA. The data on film can be scanned into a computer and a commercially available program can be used to create a standard curve where DNA quantity is plotted against the mean density of each slot blot signal. The methods described can also be applied to the very sensitive determination of quantity and quality (size) of DNA on Southern blots. The high sensitivity of this quantitation method requires the consumption of only a fraction of sample for analysis. Determination of DNA quantity is necessary for RFLP and many PCR-based tests where optimal results are obtained only with a relatively narrow range of DNA quantities. The specificity of this quantitation method for human DNA will be useful for the analysis of samples that may also contain bacterial or other non-human DNA, for example forensic evidence samples, ancient DNA samples, or clinical samples.     

ＤＮＡ粗提取与鉴定的简易方法

介绍一种在中学可行的ＤＮＡ提取与鉴定的简易方法,该法可以不使用 离心机和一些特殊的昂贵的药品。     

一种粗糙脉孢霉基因组DNA的快速制备方法

粗糙脉孢霉基因组ＤＮＡ的制备方法一般很费工费时。ＷｅｎｄｌａｎｄＪＡ等人发展了一种丝状真菌的ＤＮＡ提取方法 ,应用在裂褶菌取得了良好的效果[1] 。本文基于该方法制备粗糙脉孢霉基因组ＤＮＡ也取得了成功 ,应用ＰＣＲ从基因组扩增出了一个与无机焦磷酸酶有同源性的基因。1　材料与方法1 1　菌种 :粗糙脉孢霉 (Ｎｅｕｒｏｓｐｏｒａｃｒａｓｓａ)菌种 490 7ｐｒｄ - 4 ,ｂｄＡ ,来自ＦｕｎｇａｌＧｅｎｅｔｉｃｓｓｔｏｃｋｃｅｎｔｅｒ,ＵｎｉｖｅｒｓｉｔｙｏｆＫａｎｓａｓＭｅｄｉｃａｌＣｅｎｔｅｒ,Ｋａｎｓａｓ ,ＵＳＡ。1 2…     

A reliable general purpose method for extracting genomic DNA from Dictyostelium cells

In this protocol, we present a standard method for extracting DNA from cells of the social amoeba Dictyostelium discoideum. While this procedure is similar to other phenol:chloroform-based purification methods, it is modified to account for the high level of carbohydrate and nucleases found in Dictyostelium cells. Genomic DNA can be isolated from wild-type and genetically modified cells using the described protocol, allowing molecular genetic analyses to be performed. Following cell lysis, nucleic acid extraction, and precipitation, the isolated DNA is suitable for digestion by restriction enzymes, amplification by PCR and Southern blotting. This procedure takes approximately 3 h to complete.     

A noninvasive method for extracting bivalve DNA from the water-filled mantle cavity

Genetic studies play a great role for determining the biology of bivalves, particularly those covering population genetics, phylogeny, breeding, stock management, and conservation. However, DNA sampling methods that require removal of bivalves from the water and/or opening of their shells often cause stress and damage to bivalves, which can be lethal. The invasiveness of DNA sampling has made it difficult to conduct genetic studies in threatened species, rare species, and/or breeding lineages. In the present study, we developed a non-invasive method for bivalve DNA sampling using the water-filled mantle cavity (WMC). Our method can extract DNA from a small WMC sample (about 100 µl), collected using a fine needle and syringe without opening the shell. We demonstrated that the WMC sample contains intact mitochondrial and nuclear DNA. DNA contamination from other organisms, such as adjacent bivalve individuals, did not affect the resulting PCR and DNA sequencing analyses. Finally, the individuals from whom WMC was collected remained alive for more than 2 months after the experiments. This non-invasive method will be of great assistance in investigating the genetics of bivalves.

     

A rapid, efficient method for isolating DNA from yeast

A method is described for the purification of chromosomal and plasmid DNA from the yeast Saccharomyces cerevisiae. This method is rapid, gives 75% of theoretical yield, and produces DNA that can be cut with restriction endonucleases. Yeast cells are treated with zymolyase, and the resulting spheroplasts are lysed in the presence of the chaotropic agent guanidine hydrochloride. After a brief ethanol precipitation, protein is removed by treatment with proteinase K followed by phenol-chloroform extraction. After ethanol precipitation, the DNA is sufficiently pure for restriction analysis or for the transformation of Escherichia coli.     

Simple method for extracting plasmid DNA from lactic acid bacteria

Rapid screening and large-scale plasmid DNA isolation procedures are described for lactic acid bacteria, using glass beads to break cells. The rapid screening procedure allows one to obtain plasmid DNA pellets in less than 1 h. This method has been successfully tested on various bacteria from the genera Lactococcus, Leuconostoc, Lactobacillus, Pediococcus, Streptococcus, Enterococcus and Propionibacterium. This procedure yields plasmid DNA with minor chromosomal and plasmid DNA-degraded form contaminations.