Recently Viewed

BcuI (SpeI)

5'...AC T A G T...3'
3'...T G A T CA...5'

Available as a FastDigest enzyme for rapid DNA digestion

FastDigest enzyme available Tango buffer for 100% activity Optimal incubation at 37°C Not inactivated at 80°C in 20 min Genome qualified LO certified

The BcuI (SpeI) restriction enzyme recognizes A^CTAGT sites and cuts best at 37°C in Tango buffer (Isoschizomers: AhlI, SpeI)
Ad2 DNA digested with BcuI (SpeI)

Ad2 DNA digested with BcuI (SpeI), 0.7% agarose, 3 cleavage sites

Thermo Scientific conventional restriction endonucleases are a large collection of high quality restriction enzymes, optimized to work in one of the buffers of the Five Buffer System. In addition, the universal Tango buffer is provided for convenience in double digestions. All of the enzymes exhibit 100% activity in the recommended buffer and reaction conditions. To ensure consistent performance, Thermo Scientific restriction enzyme reaction buffers contain premixed BSA, which enhances the stability of many enzymes and binds contaminants that may be present in DNA preparations.


  • Superior quality – stringent quality control and industry leading manufacturing process
  • Convenient color-coded Five Buffer System
  • Includes universal Tango buffer for double-digestions
  • BSA premixed in reaction buffers
  • Wide selection of restriction endonuclease specificities


  • Molecular cloning
  • Restriction site mapping
  • Genotyping
  • Southern Blot
  • Restriction fragment length polymorphism (RFLP)
  • SNP


For methylation sensitivity refer to product specifications.

Compatible EndsXmaJI, Eco130I, NheI, XbaI.
Conditions for 100% Activity
  • 1X Buffer Tango: 33 mM Tris-acetate (pH 7.9 at 37°C), 10 mM Mg-acetate, 66 mM K-acetate, and 0.1 mg/mL BSA
  • Incubate at 37°C
Digestion of Agarose-embedded DNAMinimum 10 units of the enzyme are required for complete digestion of 1 µg of agarose-embedded Adenovirus-2 DNA in 16 hours.
Double DigestionPerform double digestion using DoubleDigest.
IsoschizomersSearch for commercial isoschizomers using REsearch.
NoteAssayed using pUC19 DNA with insert, containing BcuI recognition site.
Storage BufferBcuI is supplied in: 10 mM Tris-HCl (pH 7.5 at 25°C), 300 mM KCl, 1 mM DTT, 0.1 mM EDTA, 0.2 mg/mL BSA, and 50% (v/v) glycerol.
Storage Condition-20 C

Reaction conditions

Recommended buffer for 100% activity Optimal temperature Enzyme activity in Thermo Scientific buffers, % Tango buffer for double digestion
B (blue)
G (green)
O (orange)
R (red)
Tango (yellow)
1X / 2X
Tango 37°C 50-100 50-100 0-20 20-50 100 0-20 1X

Methylation Effects

  • Dam: never overlaps - no effect.
  • Dcm: never overlaps - no effect.
  • CpG: never overlaps - no effect.
  • EcoKI: may overlap - effect not determined.
  • EcoBI: may overlap - effect not determined.

Cleavage efficiency close to the termini of PCR fragments

bp from the recognition site to fragment end
1 2 3 4 5

Number of recognition sites in DNA molecules

Lambda ΦX174 M13mp18/19 pBR322 puc18/19 pUC57
0 0 0 0 0 0
pTZ19R/U pTZ57R pBluescriptIIKS(±) pBluescriptIISK(±) pACYC177 pACYC184
0 0 1 1 0 0

New sites generated by ligation

Newly generated recognition sites resulting from ligation of protruding compatible DNA ends

Recognition Sequence Second Enzyme Enzymes recognizing newly generated recognition sequence
  • Eco130I (StyI)/FastDigest StyI (Eco130I)* (C^CTAGG)
  • NheI/FastDigest NheI (G^CTAGC)
  • XbaI/FastDigest XbaI (T^CTAGA)
  • XmaJI (AvrII)/FastDigest AvrII (XmaJI) (C^CTAGG)
  • FspBI (BfaI)/FastDigest BfaI (FspBI)

Newly generated recognition sites resulting from fill-in of 5'-overhang and self-ligation

Recognition Sequence Newly generated sequence after reaction Enzymes that cleave the newly generated sequence
  • AluI/FastDigest AluI
  • CviJI
  • [FspBI (BfaI)/FastDigest BfaI (FspBI)]
  • SetI