Tubulin Protein - Lyophilized
Isolated to >99% by selective precipitation and lyophilized for storage at room temperature.
Molecular Weight: ~110 kDa
Form: desiccated powder (1 mg tubulin protein is supplied as 3 mg powder with extra mass attributed to trehalose, a lyoprotectant)
Buffer Conditions Upon Reconstitution: 10 mM Sodium Phosphate, 0.5 mM MgCl2, 0.1 mM GTP, and 0.25 M Trehalose (pH 7.0)
Shipping: shipped at ambient temperatures
Storage Conditions: store in a cool, dry environment
Shelf Life: check product label for expiration date
Lyophilized Tubulin is isolated by selective precipitation from bovine brain homogenate by an adaptation of the method of Andreu (2007) and lyophilized by an adaptation of the method of Dráberová et al. (2010). The resulting tubulin protein is >99% pure (Figure 1) and polymerization competent (Figure 2). Lyophilized Tubulin is supplied as a white powder. When reconstituted with ultrapure water to 40 mg/ml, the buffer conditions are 10 mM Sodium Phosphate, 0.5 mM MgCl2, 0.1 mM GTP, and 0.25 M Trehalose, pH 7.0. Note that 1 mg tubulin protein is supplied as 3 mg powder (extra mass attributed to trehalose, a lyoprotectant), and reconstitution/dilution should be based on the tubulin protein concentration.
Activity and Applications
Lyophilized Tubulin will polymerize into microtubules when supplemented with guanosine-5'-triphosphate (GTP), warmed to 37˚C, and kept above its critical concentration. Polymerization activity is detectable in a variety of experimental systems including fluorescence microscopy assays, turbidity assays, and GTPase assays. Lyophilized Tubulin is suitable for use in a variety of cell-free experimental applications and can be combined with fluorescent or biotinylated tubulin proteins in generating microtubules in vitro. Visit our protocols page for common microtubule polymerization protocols, including the generation of short, rigid microtubules stabilized by GMPCPP or long, flexible microtubules stabilized by taxol.
- structural analysis by X-ray crystallography and electron microscopy
- drug discovery by high-throughput screening
- in vitro biochemical and biophysical approaches
- kinase phosphorylation assays
Tubulin Protein Stored and Shipped at Room Temperature
Lyophilized Tubulin is >99% pure. Coomassie G250-stained protein gel of Lyophilized Tubulin separated by SDS-PAGE. The tubulin protein appears as a single species migrating at ~55 kDa. Molecular weight markers and loaded protein quantities are indicated.
Lyophilized Tubulin is polymerization-competent. Optical density (340 nm) of Lyophilized Tubulin at 5 mg/ml in Tubulin PEM Buffer (Cat. No. 032003; 80 mM PIPES, 1 mM EGTA, and 1 mM MgCl2, pH 6.8) supplemented with 1 mM GTP and 20% glycerol at 37°C. Distinct nucleation and polymerization phases are evident.