Recovery of bulk DNA from soil by a rapid, small-scale extraction method

PCR amplification of crude microbial DNA extracted from soil

“…and Olson 1992a). Typical purification steps include CsClethidium bromide density gradient centrifugation (Holben et al 1988 ;Steffan et al 1988 ;Porteous and Armstrong 1991),…”

Extraction of DNA from soil

“…Improvement in DNA purity may result from the lysozyme hydrolytic action on glycosidic or other humic components bonds. Another enzyme, achromopeptidase, was used to improve the lysis of the recalcitrant Gram positive Frankia [61] and another, proteinase K, was used to digest contaminating proteins [37,50,77].…”

“…Nucleic acid binding on hydroxyapatite columns was successful for extracting DNA [46,63] and both DNA and rRNA [52] from soil and sediment samples. Cesium chloride (CsCl) density gradient centrifugation was also shown to allow further enzymatic restriction of purified nucleic acids [46,50]. In contrast, Steffan et al [63] noted that even extensive purification with CsCl gradient centrifugation and hydroxyapatite chromatography resulted in DNA loss and did not remove all humic acids.…”

From bacterial genomics to metagenomics: concept, tools and recent advances

“…The similar physico-chemical properties of humic acids to those of nucleic acids [69] make it diffi cult to remove them during DNA extraction. These contaminants can inhibit certain restriction endonucleases [70][71][72][73] and also Taq polymerase. It becomes almost impossible to obtain PCR amplifi cation from the extracted DNA containing humic acid content as low as 0.08μg/ml since most of the Taq polymerases are inhibited at this concentration [74].…”