The COOL-tag is a monomeric, soluble 28.5kDa engineered fragment of a Penicillin Binding Protein.
The COOL-tag binds rapidly and efficiently to ampicillin sepharose at room temperature by forming an ester bond via a serine residue.
The target protein can then be eluted at 4C or via competitive elution with ampicillin.
Rapid Binding
COOL-tagged target protein rapidly binds to ampicillin sepharose. Saturation is achieved after 60 minutes. Up to 10mg/ml protein can be bound to the resin.
High Compatibility
COOL-tag technology is compatibile with salt concentrations up to 1M, works in your buffer of choice at pH 7.5 and is suitable for use with non-ionic detergents such as triton 0.2% X-100 (T) or 0.06% Brij35 (B).
COOL-tag Key Features:
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Ligand free, temperature induced elution or Ampicillin-mediated elution
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Truly 1 step purification no need to desalt of buffer exchange after elution
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Exceptional purity, high yielding and high recovery
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Cysteine and metal free chemistry: No interference with metallo-protein function, e.g. metalloproteases, ubiquitin ligases
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Monomeric protein: no dimerisation via the tag
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Suitable for analytical or preparative scale
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Suitable for Mammalian, insect, bacterial, yeast and dictyostelium expression
High Specific affinity
Unlike other tags, only COOL-tagged proteins bind the resin. As demonstrated by the pulldown of 2mg HEK 293 protein extract with 20μl different resin. Ni-Sepharose (lane 1) pulls down many contaminants, GST-sepharose (lane 2) nonspecifically binds GST and carbonyl reductase, Ampicilin sepharose (lane 3) does not bind contaminants.
Ligand Free Elution at 4C
COOL-tagged protein can be eluted either at 4C or storing the sample on ice or competitively with ampicilin. Ampicilin mediated elution is slighty faster. Protein recovery is excellent for both methods.
COOL-tag vs GST-TAG
Transient transfection of GST-SPAK or COOL-SPAK in 293 cells.
* Due to leakage at precision site
IDT
