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Enzymes and buffers from different companies - (Jun/13/2013 )

I want to do a double digest with BamHI and HindIII.

Enzymes from Promega work in the same buffer ( B ). But my BamHI is from Fermentas and it works in unique BamHI buffer. The compositions of the buffers are not identical.

The question is: can I do double digest in Promega buffer or it is better to do a sequential digest using proper buffer for each enzyme?

Are there any differences between same enzyme but from different companies?

Thanks for help!


Check salt concentrations on website:

Fermentas BamHI Buf:
1X Composition:

<*>10mM Tris-HCl (pH 8.0 at 37°C)
<*>5mM MgCl2
<*>100mM KCl
<*>0.02 % Triton X-100
<*>0.1mg/mL BSA

Promega HindIII:


Buffer B Promega:

6mM Tris-HCl (pH 7.5 at 37°C)
6mM MgCl2
50mM NaCl

Compositions and salt concentrations of these buffers are different.

Does it mean that enzymes can work in different conditions? Or each company somehow adjust its enzymes so they work only in specific buffers?

Thanks for helping me!


In most cases the protein from different manufacturers is identical. These buffers are very similar, the major difference being the KCl and NaCl ion and concentration difference. I'd wager that either enzyme will work in both, possibly with some star reaction behavior.


What is CutSmart Buffer? Over 200 restriction enzymes are 100% active in a single buffer, CutSmart Buffer:
CutSmart Buffer:
50 mM Potassium Acetate
20 mM Tris-acetate
10 mM Magnesium Acetate
100 μg/ml BSA
pH 7.9


All new NEB.1 buffers are now supplemented with BSA. The cut smart buffer is almost completely identical to NEB #4, with the exception of 1mM DTT. I was worried about this as well, but I have not seen any difference in activity between the new cutsmart buffer and NEB #4. The new NEB.1 buffers just make it easier when the enzymes require BSA for 100% efficiency.


Thank you for answers everyone!