| Description | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | The content of this cell is too long for an XLSX file (more than 32767 characters). Please use the CSV format for this export | Bacterial protein extraction reagents use mild non-ionic detergents and are suitable for extracting recombinant proteins expressed in Escherichia coli and insect cells. During the extraction process, there is no need for ultrasonic fragmentation, effectively avoiding contamination of exogenous Bacterial protein extraction reagents use mild non-ionic detergents and are suitable for extracting recombinant proteins expressed in Escherichia coli and insect cells. During the extraction process, there is no need for ultrasonic fragmentation, effectively avoiding contamination of exogenous proteins. This product can be applied to extract soluble proteins from bacterial lysates. The bacterial protein extraction kit adds a mixture of lysozyme, DNase I, and protease inhibitors to the extraction reagent, which can improve the efficiency of protein extraction and reduce the viscosity caused by DNA, effectively avoiding protein degradation. The extracted protein maintains biological activity and can be subjected to downstream operations such as IP, Western blot, and protein purification. Component B665764 100 preps Bacterial Protein Extraction Reagent 100 ml Protease Inhibitor Cocktail (100x) 1 ml Lysozyme （50 mg/ml） 200µl DNaseⅠ（1,000 U/ml） 100µl Notes:1. This product is suitable for extracting proteins from fresh or frozen bacterial and insect cells.2. This product uses Tris buffer system. Please use the same buffer system for protein purification after extraction.3. The protein lysis solution obtained from this product can be used for protein quantification using BCA or Bradford method.4. For special strains, if the extraction effect is not ideal, the sample can be frozen before protein extraction.5. Depending on the specific situation, protease inhibitors, salts, chelating agents, reducing agents, etc. can be added to this product.Operation steps: ● Insect cell protein extraction1. Collect cells by low-speed centrifugation. Add 10 to every 1 ml of Bacterial Protein Extraction Agent µ The Protein Inhibitor Cocktail is 1 x working fluid.2. Weigh the wet weight of the cells and add 1 x working solution at a rate of 10 ml/g.3. After resuspension, incubate on ice for 20 minutes (the ice storage time should be adjusted according to different cell types).Centrifuge at 4.15000 × g for 15 minutes to isolate soluble proteins. ● Extraction of soluble bacterial proteins 1. Centrifuge for 10 minutes at a rate of 5000 × g and collect the bacterial cells.2. Optional steps: Add 1 ml of Bacterial Protein Extraction Reagent every 1 ml µ DNase I (1000 U/ml), 2 µ Lysozyme (50 mg/ml) and 10 µ Protein Inhibitor Cocktail, vortex oscillation and mixing. 3. Add 20 ml of Bacterial Protein Extraction Reagent to each gram of bacterial precipitate, and add the extraction solution to the bacterial precipitate. Vortex thoroughly or use a pipette to blow up and down until the bacterial precipitate is completely resuspended.4. After resuspension, incubate at room temperature for 10-15 minutes (the storage time should be adjusted according to different cell types). 5. Centrifuge at 15000 × g for 5 minutes.6. Transfer the supernatant to a new centrifuge tube (the supernatant is soluble protein) for protein quantification and downstream experiments.Note: If the target protein exists in the form of inclusion bodies, inclusion body protein solution can be used for dissolution or expression conditions can be optimized to increase the expression of soluble proteins.Frequently asked questions: Problem Possible reasons Resolvent The target protein is insoluble The target protein is expressed as an inclusion body Optimize expression conditions or add Lysozyme and DNase I to protein extraction reagents using inclusion body protein solution After adding Lysozyme, the target protein has not been extracted yet Temperature too low Restore the reagent to room temperature After adding Lysozyme, the target protein has not been extracted yet Lysozyme Decreased or inactivated activity Add more Lysozymes or replace with new enzymes Extract has high viscosity DNase I Decreased or inactivated activity Add more DNase I or replace with a new DNase I to increase the final concentration of magnesium ions to 2 mM After protein extraction, most of the proteins still exist in the precipitate Excessive protein content Add Lysozyme and DNase I The protein extraction reagent has sediment precipitation Temperature too low Restore the protein extraction reagent to room temperature... Read More | Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly Calcein AM /PI Double Staining Kitis utilized for simultaneous fluorescence staining of viable and dead cells. This kit contains Calcein-AM and Propidium Iodide (PI) solutions, which stains viable and dead cells, respectively(Fig. 1). Calcein-AM, an acetoxymethyl ester of calcein, is highly lipophilic and cell membrane permeable. Though Calcein-AM itself is not a fluorescent molecule, the calcein generated from Calcein-AM by esterase in a viable cell emits a strong green fluorescence (excitationat 490 nm, emission at515 nm). Therefore, Calcein-AM only stains viable cells. On the other hand, PI, a nuclei staining dye, cannot pass through a viable cell membrane. It reaches the nucleus by passing through disordered areas of dead cell membrane, and intercalates with the DNA double helix of the cell to emit red fluorescence (excitation: 535 nm,emmision: 617 nm). Since both calcein and PI-DNA can be excited with 490 nm, simultaneous monitoring of viable and dead cells is possible with a fluorescence microscope. With 545 nm excitation, only dead cells can be observed (Fig. 1). Since optimal staining conditions differ from cell line to cell line, we recommend that a suitable concentration of PI and Calcein-AM be individually determined. Please note that PI is suspected to be highly carcinogenic;careful handling is required.Required Equipment and Materials:Microscope with 490 nm excitation filter and 530 nm emission filter；CO2incubator；10 µl and 200 µl adjustable pipettes, PBSSolution A (Calcein-AM)；Solution B (PI) Storage Condition: -20oC ；Shipping Condition: blue ice.Application:Assay Procedure1)Add 2.5 µl Solution A and 12.5 µl Solution B to 5 ml PBS to prepare assay solution.*2)Wash the cell with PBS several times to remove residual esterase activity.3)Add 100uLof assay solution to200uL105~106CELLSsolution and incubate the mixture at 37oC for 15 min.4)Detect fluorescence using a fluorescence mircoscope with 490 nm excitationfor simultaneous monitoring of viable and dead cells.With 545 nm excitation, only dead cells can be observed.*The following steps may be necessary tooptimizethe suitable concentration of each reagent:1)Prepare dead cells by 10 min incubation in 0.1% saponin or 0.1-0.5% digitonin or by 30 min incubation in 70% ethanol.2)Stain dead cells with 0.1-10 µM PI solution to find a PI concentration that stains the nucleus only, not the cytosol.3)Stain dead cells with 0.1-10 µM Calcein-AM solution to find a Calcein-AM concentration that does not stain the cytosol. Then stainviable cells with that Calcein-AM solution to check whether the viable cell can be stained... Read More | Store at -20°C. Please refer to protocols |