Human Eg5 motor domain purified as GST-tagged protein; highly pure and active for in vitro assays, including Eg5 inhibitor identification.

• Substrate for microtubule (MT) activated kinesin ATPase assay
• Screen for KIF11 (Eg5) inhibitors
• Counter-screen for kinesin drug candidates

KIF11—also known as kinesin-5 or Eg5—is an essential mitotic motor protein that drives spindle pole separation and bipolar spindle assembly. Several small molecule inhibitors targeting KIF11 have been explored as anti-mitotic cancer therapies, though clinical efficacy as monotherapies has been limited, with filanesib showing promise in multiple myeloma.

The wild-type human motor domain of KIF11 is produced in a bacterial expression system.

• Protein tag: N-terminal GST-tag
• Molecular weight: 74 kDa
• Motor amino acids: 13-437
• Uniprot ID: P52732
• Formulation: supplied as lyophilized powder
• Composition: when reconstituted 80 mM PIPES pH 6.8, 100 mM NaCl, 2 mM MgCl2, 5% (w/v) sucrose, and 1% (w/v) dextran

Protein purity is assessed by scanning densitometry of Coomassie Blue-stained protein on a4-20% polyacrylamide gel. Purity is determined to be >85% pure.

Biological activity of CS-KF11 is measured using a microtubule activated ATPase assay. Under the conditions stated (see datasheet), KIF11 exhibits a microtubule-stimulated ATPase activity with a Vmax of ≥ 600 nmol of ATP produced per minute per mg of KIF11.