In the tetR detector module, it’s written:
“TetR purified protein—MedChemExpress HY-P71520, resuspended to 10 uM.”
But it’s unclear from the protocol what it should be resuspended in. It’s also unclear what should be used as a ‘carrier protein’ per the manufacturer’s recommendation for long term storage at -80C that would also be compatible with the PURE/cytosol.
Any suggestions?
BSA looks like the least risky option to be used as a carrier protein. Following the guidelines of MedChemExpress for resuspension, it should be resuspended in water + a buffer with carrier protein.
”Before opening the cap, centrifuge the vial at 13000 rpm for 20-30 seconds. This step will ensure that any lyophilized powder that may have adhered to the cap or walls is collected at the bottom of the vial, minimizing the risk of product loss. 2. Taking 10 μg as an example, first add 20 μL of reconstituted solution provided by MCE and use a pipette to gently resuspend the lyophilized protein until it is fully dissolved.. (For most proteins, the reconstitution solution we provide is sterile water. If a diluent other than water is required, it will be indicated in the product’s Certificate of Analysis (COA).). 3. Add an additional 80 μL of buffer/culture medium containing carrier protein (either 0.1% BSA, 5% HSA, 10% FBS, or 5% trehalose), and then use a pipette to gently mix until uniform. The final concentration should not be lower than 100 μg/mL. 4. Aliquot at least 20 μL per tube. 5. After aliquoting, store it frozen at a temperature ranging from -20ºC to -80ºC, and it can be preserved for 3 to 6 months.”
Any thoughts on how that would interact with Cytosol or any potential tradeoffs versus using a more standard cryprotectant like glycerol?