Other Proteins FAQs

Question 1:  What kits does Cytoskeleton offer to measure molecular motor activity?

Question 2:  Can Cytoskeleton offer custom purification of my protein?

Question 1: What kits does Cytoskeleton offer to measure molecular motor activity?

Answer 1: Kinesin motor proteins use microtubules (MTs) as a substrate to orchestrate a wide range of kinetic events within a cell.  Kinesins operate by utilizing the energy of ATP by hydrolysis, an activity that is greatly enhanced in the presence of MTs.  Microtubule activation of the ATPase activity of motor proteins can be measured with a kinesin ATPase assay.  Cytoskeleton developed two such assays, one end-point (Cat. # BK053) and one kinetic (Cat. # BK060), that are used to measure inorganic phosphate (Pi) levels generated by MT-activated kinesin adenosine triphosphatase (ATPase) activity.  These two kinesin ATPase biochem assay kits contain MTs and kinesin heavy chain (KHC) protein along with the necessary buffers and reagents to measure Pi production as a means of measuring molecular motor activity.  These kits are useful for discovering kinesin inhibitors and activators (Cat. # BK053 and BK060) as well as determining V_max and K_cat values for a kinesin motor protein (Cat. # BK060). 

Cytoskeleton, Inc. also offers a Biochem Kit (Cat. # BK027) which allows the visualization of motor protein motility using fluorescently-labeled microtubules.

Question 2: Can Cytoskeleton offer custom purification of my protein?

Answer 2: Yes, Cytoskeleton, Inc. has an active contract services department that performs custom purifications to produce purified recombinant proteins with high biological activity.  Examples of protein purification projects are:

• Tubulin proteins isolated from cancer cell lines which are useful for developing drugs targeted toward cancer cells. We have isolated 1.0-5.0 mg of 90% pure tubulin from 50 g of cells.
• Small G-protein Arf1 and Arf6 purified within 8 weeks to >85% purity and suitable for 10,000 GEF assays (50 x 1 mg).

We perform full quality control, which includes:

• Full quantitation of yield, in mg per g tissue.
• SDS-PAGE analysis of purified proteins, stained with Coomassie Blue and scanned with a densitometer to estimate purity.
• Biological activity determination depending on the requirements of the customer.

The delivery time usually depends on the protein or type of assay, but 4 to 8 weeks is normal. 

The cost depends on the quantity and quality of the protein required, and also on whether the preparation is simple or complex. The normal range is $8,000 to $12,000. However, there are circumstances where we may consider a lower cost if we can introduce the protein into our range of products.  There is an initial deposit of 50% of the total cost which is non-refundable. The remaining 50% is due 30 days after the product has been delivered.

Please send an e-mail describing your requirements to tservice@cytoskeleton.com and provide the following information to expedite the creation of a quotation:

• Contact information
• Gene accession number
• Assay type
• Assay quantity
• CV required
• Purity and yield required