货品编号： Invitrogen.AM2222 品牌： Invitrogen 品名： Ambion™ DNase I (RNase-free)酶 规格： 2000u/支 储存条件： –20°C

产品描述

Ambion DNase I (RNase-free) (E.C. 3.1.21.1) is a nonspecific endonuclease that degrades double- and single-stranded DNA and

chromatin. It functions by hydrolyzing phosphodiester linkages, producing mono and oligonucleotides with a 5'-phosphate and

a 3'-hydroxyl group. RNase-free DNase I is of the highest purity available and is recommended to degrade DNA in the presence of

RNA when the absence of RNase is critical to maintain the integrity of the RNA. For example, DNase I is frequently used to remove

template DNA following in vitro transcription, and to remove contaminating DNA in total RNA preparations (especially those from

transfected cells that may contain plasmid DNA), used for ribonuclease protection assays, cDNA library contraction, and RT-PCR.

DNase I requires bivalent cations (Mg2+ and Ca2+ at approximately 5 mM and 0.5 mM, respectively) for maximal activity, and has

a pH optimum of 7.8.

RNase-free DNase I outperforms the competition A research report in BioTechniques (Matthews et al., 32: 1412-1417, 2002) compared RNase contamination in DNase I preparations

from Sigma, Roche, Applied Science, Qiagen, and Ambion. The results revealed that "...with the exception of Ambion®'s RNase-free

DNase I, the integrity of cRNA from in vitro transcription reactions was compromised and was still contaminated with DNA. Ambion®'s

DNase was used for the remaining experiments requiring DNase digestion...". Ambion® DNase I is tested for contaminating RNase and

protease activity. Functionality is determined by digestion of human genomic DNA followed by quantitative real-time PCR to detect

undigested DNA.