+3
Tubulin is purified from porcine brain using a modified Shelanski et al. method, followed by cation exchange chromatography to achieve >99% purity. Supplied at 10 mg/ml in G-PEM buffer (80 mM PIPES pH 6.9, 2 mM MgCl₂, 1 mM EGTA, 1 mM GTP). Shipped on dry ice and stored at –80 °C.
Tubulin is a heterodimer of α- and β-isotypes, each 55 kDa. SDS-PAGE shows a single 55 kDa band. The molecular weight of the functional heterodimer is 110 kDa.
Protein purity is assessed by scanning densitometry of Coomassie Blue stained protein on a 4-20% polyacrylamide gel. Purity is determined to be >99% pure.
The biological activity of T238P is evaluated using a tubulin polymerization assay, which monitors microtubule formation by measuring absorbance at 340 nm. Under the test conditions (5 mg/ml tubulin in General Tubulin Buffer with 5% glycerol and 1 mM GTP, 180 µl volume, 37°C, 0.8 cm pathlength), the OD340nm should reach between 0.75 and 1.0 within 30 minutes.
Cat. #T238P
