商品编号


X40520K



品牌


Lucigen



公司


Lucigen



公司分类


DNA Nucleases




20,000 Units


商品信息

Digest ssDNA, but not dsDNA, in a 3? to 5? direction

Specific
: Processively digest ssDNA in a 3? to 5? direction without harming dsDNA - short 3? overhangs in DNA are not digested

Flex
IBL
e
: Active under a wide variety of buffer conditions and can be added directly into most reaction mixes

Heat Inactivated
: Destroy the enzyme activity by incubating at 80°C for 15 minutes




Exonuclease I digests ssDNA in a 3? to 5? direction,
1-3
but does not digest dsDNA. Although it requires the presence of magnesium and a free 3?-hydroxyl terminus for activity, it is active under a wide variety of buffer conditions and can be added directly into most reaction mixes. Exonuclease I can be heat-inactivated by incubation at 80°C for 15 minutes.

Applications

Removal of residual ssDNA, including oligos, from reaction mixes.

Removal of ssDNA from nucleic acid mixtures.

Unit Definition:
One unit of Exonuclease I catalyzes the release of 10 nmol of acid-soluble nucleotides from heat-denatured calf thymus DNA in 30 minutes at 37°C under standard assay conditions.

Storage Buffer:
50% glycerol containing 50 mM Tris-HCl (pH 7.5), 0.1 M NaCl, 0.1 mM EDTA, 1 mM DTT, and 0.1% Triton? X-100.

Quality Control:
Exonuclease I is tested in degradation of ssDNA and is free of detectable RNase, endonuclease, and double-stranded exonuclease activities.

References


Lehman, I.R. and Nussbaum, A.L. (1964)
J. Biol. Chem.

239
, 2628.

Kushner, S.R.
et al.
(1971)
Proc. Natl. Acad. Sci.

USA

68
, 824.

Kushner, S.R.
et al.
(1972)
Proc. Natl. Acad. Sci. USA

69
, 1366.



Figure 1. Specificity of Exonuclease I for ssDNA
. 200 ng of
Eco
R I-linearized pUC19 dsDNA and 1 ?g of a 100-mer ssDNA oligo were mixed in 1X TA Buffer and incubated at 37°C for 20 min in the absence or presence of 10 units of Exonuclease?I. As seen on this 1% agarose gel, Exonuclease I completely digested the linear ssDNA oligo, but left the linearized plasmid dsDNA intact. Lane 1, size
Marker
s; Lane 2, minus
Exo
I; Lane 3, plus
Exo
I.