Product Catalog

Sequence specificity
Alu I recognizes the sequence *AG↓*CT and generates fragments with blunt termini.

Source
From Arthrobacter luteus

Compatible ends
The enzyme generates ends that are compatible with any blunt end.

Isoschizomers
Alu I is not known to have isoschizomers.

Methylation sensitivity
Alu I is inhibited by the occurrence of 6-methyladenine, 5-methylcytosine, 5-hydroxymethylcytosine or 4-methylcytosine at the sites indicated (*) in the recognition sequence.

Activity in SuRE/Cut buffer System
Buffer printed in bold face type is the buffer recommended for optimal activity:

Relative activity in complete PCR mix
Taq DNA Polymerase PCR mix: 100%.

Incubation temperature
37°C

Unit definition
One Unit is the enzyme activity that completely cleaves 1 μg λDNA in 1 h at 37°C in SuRE/Cut Buffer A in a total volume of 25 μl.

Heat inactivation
The enzyme can be heat inactivated by incubating it for 15 min at 65°C.

Number of cleavage sites on different DNAs

1. Alu I
2. SuRE/Cut buffer A (10x)

Absence of nonspecific endonucleases
1 μg λDNA is incubated for 16 h in 50 μl SuRE/Cut buffer A with excess Alu I. The number of enzyme units that may be included in the incubation mixture without changing the enzyme-specific digestion pattern is stated under "Endo" (on the product label).

Absence of 5´-exonuclease/ 5´-phosphatase activities
5´-[³²P] terminally labeled λ× Hpa II fragments are incubated with Alu I for 4 h at 37°C in SuRE/Cut buffer A. After products are separated by TLC, the amount of radioactivity released (detection limit: 0.1%) is calculated as a percentage of input radioactivity, then divided by the number of units of Alu I. That percentage is stated under "5´-Exo" (on the product label).

Absence of 3´-exonuclease activity
3´-[³²P] terminally labeled  λ × Hpa II fragments are incubated with Alu I for 4 h at 37°C in SuRE/Cut buffer A. After products are separated by TLC, the amount of radioactivity released (detection limit: 0.1%) is calculated as a percentage of input radioactivity, then divided by the number of units of Alu I. That percentage is stated under "3´-Exo" (on the product label).

Ligation and recutting assay
Alu I fragments obtained by complete digestion of 1 μg pBR322 DNA are ligated for 16 h at 4°C with 0.1 U T4-DNA ligase in 10 μl buffer that contains 66 mM Tris-HCl, 5 mM MgCl₂, 1 mM dithioerythritol, 1 mM ATP, pH 7.5 (at 20°C). The percentages of product that can be ligated and subsequentally recut with Alu I (yielding the typical pattern of pBR322 × Alu I fragments) are determined and are stated under "Lig" and "Rec" (on the product label). 

• Klenow Enzyme Labeling grade, from Escherichia coli lysogenic NM 964;
  
• DNA Molecular Weight Marker XIV (100 bp ladder);
  
• Rapid DNA Ligation Kit;
  For rapid and efficient DNA ligation.