Cat. No. / ID: P7460L
Poly(A) Polymerase attaches ATP (catalyzed from AMP) to the 3ʹ hydroxyl of RNA, which is useful for making poly(A)-tailed RNA.
The enzyme is supplied in 25 mM Tris-HCl, 500 mM NaCl, 1 mM MgCl2, 0.1 mM DTT, 0.1 mM EDTA and 50% glycerol; pH 8.0 at 25°C.
The reaction buffer for Poly(A) Polymerase at 10x concentration includes 500 mM Tris-HCl, 2.5 M NaCl, and 100 mM MgCl2, with a pH of 7.9 at 25°C.
Poly(A) Polymerase catalyzes the addition of AMP from ATP to the 3ʹ hydroxyl of RNA. The reaction requires Mg2+ and is template independent.
|Specific activity||>20,000 U/mg|
|Single-stranded exonuclease||200 U||<5% released|
|Double-stranded exonuclease||200 U||<1% released|
|Double-stranded endonuclease||200 U||No conversion|
|E. coli DNA contamination||100 U||<10 copies|
|RNase contamination||200 U||No detectable non-specific RNase|
The protein is produced by an E. coli strain expressing the Poly(A) Polymerase gene from a plasmid.
One unit is defined as the amount of enzyme that will incorporate 1 nmol of ATP into acid-insoluble material in 10 minutes at 37°C.
1. Set up the following reaction mixture in a total volume of 20 µL in the order listed:
2. Incubate the reaction mixture at 37°C for 30 minutes.
3. Stop the reaction by adding EDTA (final concentration of 10mM) or proceed to the cleanup step.
Specific activity was measured using a twofold serial dilution method. Dilutions of the enzyme were made in 1x reaction buffer (50 mM Tris-HCl, 250 mM NaCl, 10 mM MgCl2, pH 7.9 at 25°C, and added to 50 µL reactions containing a 15-mer RNA oligo, 1x reaction buffer, 1 mM ATP, 2.5 mM MnCl2 and 3H-ATP. Reactions were incubated for 10 minutes at 37°C, placed on ice, and analyzed using the method of Sambrook and Russell (Molecular Cloning, v3, 2001, pp. A8.25-A8.26).
Protein concentration is determined by OD280 absorbance.
Physical purity is evaluated by SDS-PAGE of concentrated and diluted enzyme solutions followed by silver-stain detection. Purity is assessed by comparing the aggregate mass of contaminant bands in the concentrated sample to the band's mass corresponding to the protein of interest in the diluted sample.
Single-stranded exonuclease is determined in a 50 µL reaction containing a radiolabeled single-stranded DNA substrate and 10 µL of enzyme solution incubated for 4 hours at 37°C.
Double-stranded exonuclease activity is determined in a 50 µL reaction containing a radiolabeled double-stranded DNA substrate and 10 µL of enzyme solution incubated for 4 hours at 37°C.
Double-stranded endonuclease activity is determined in a 50 µL reaction containing 0.5 µg of plasmid DNA and 10 µL of enzyme solution incubated for 4 hours at 37°C.
E. coli contamination is evaluated using 5 µL replicate samples of enzyme solution that are denatured and screened in a TaqMan qPCR assay for the presence of contaminating E. coli genomic DNA using oligonucleotide primers corresponding to the 16S rRNA locus.
Non-specific RNAse contamination is assessed using the RNAse Alert kit (Integrated DNA Technologies), following the manufacturer’s guidelines.
This product is available for molecular biology applications such as: