| Description | This reagent kit is suitable for simultaneously isolating and purifying genomic DNA, total RNA, and total protein from the same cell or tissue sample. This product does not require dividing the sample into three parts to extract DNA, RNA, and protein separately, nor does it require dividing the This reagent kit is suitable for simultaneously isolating and purifying genomic DNA, total RNA, and total protein from the same cell or tissue sample. This product does not require dividing the sample into three parts to extract DNA, RNA, and protein separately, nor does it require dividing the purified total nucleic acid into two parts before purifying DNA and RNA separately. Therefore, it can maximize the recovery of DNA, RNA, and protein, and can be used for the purification of nucleic acid and protein in small and rare samples. The purified DNA, RNA, and protein can be eluted separately and directly applied to various downstream molecular biology operations. This reagent kit does not contain toxic substances such as phenol and chloroform, and does not require ethanol precipitation. The operation is simple and fast. The extracted genomic DNA can be used for PCR, Real time PCR, SouthBlot, Dot Blot, comparative genomic hybridization (CGH), gene analysis, and SNP analysis; Total RNA can be applied in experiments such as RT-PCR, cDNA synthesis, Northern Blot, Dot Blot, and gene chips; Total protein can be applied in electrophoresis and Western Blot, among others. A665492 Component 50 T Storage A665492A Buffer RL 35 mL RT A665492B Buffer RW1 40 mL RT A665492C Buffer RW2 (concentrate) 11 mL RT A665492D RNase-Free Water 10 mL RT A665492E Buffer GW1 (concentrate) 13 mL RT A665492F Buffer GW2 (concentrate) 15 mL RT A665492G Buffer GE 15 mL RT A665492H Buffer PZ 60 mL RT A665492I Buffer PLS 15 mL RT A665492J Spin Columns DM with Collection Tubes 50 sets RT A665492K Spin Columns RM with Collection Tubes 50 sets RT A665492L Collection Tubes 100 EA RT A665492M RNase-Free Centrifuge Tubes (1.5 mL) 100 EA RTSelf prepared reagents:β- Mercaptoethanol (for newly opened or RNA extraction), 70% ethanol (prepared with water without RNase), and anhydrous ethanol.Preparation and important precautions before the experiment:To prevent RNase pollution, attention should be paid to the following aspects:1) Use plastic products and gun heads without RNase to avoid cross contamination.2) Glassware should be dry baked at a high temperature of 180 ℃ for 4 hours before use, while plastic containers can be soaked in 0.5 M NaOH for 10 minutes, thoroughly rinsed with water, and then sterilized under high pressure.3) The solution should be prepared using water without RNase.4) Operators should wear disposable masks and gloves, and change gloves frequently during the experiment.2. The sample should avoid repeated freeze-thaw cycles, otherwise it will affect the quality of DNA, RNA, and protein extraction. The sample can be stored in Buffer RL at -70 ℃ for one month.3. Please add Buffer RL before use β- Mercaptoethanol, 1 ml Buffer RL with 10 µ L β- Mercaptoethanol. join β- The buffer RL room temperature of mercaptoethanol can be stored for one month.Before the first use, anhydrous ethanol should be added to Buffer RW2, Buffer GW1, and Buffer GW2 according to the instructions on the reagent bottle label.5. Before use, please check if there is any crystallization or precipitation in the Buffer RL. If there is any crystallization or precipitation, please dissolve it again in a 56 ℃ water bath.6. All centrifugation steps are performed using a desktop centrifuge at room temperature. Operation steps:1. Material processing1a The cells cultured on the wall should be first processed into cell suspension (maximum extraction amount of 107 cells), collected cells, discarded the culture medium, and added 600 cells µ L Buffer RL (check if it has been added before use) β- Mercaptoethanol), repeatedly blow and beat to fully decompose.Attention: It is necessary to discard the culture medium completely, otherwise it will affect the lysis and subsequent nucleic acid purification steps.1b Take no more than 30 mg of animal tissue, grind it into fine powder with liquid nitrogen, and add 600 µ Buffer RL (check if it has been added before use) β- Mercaptoethanol, or directly add 600 µ L Buffer RL (check if it has been added before use) β- Mercaptoethanol, homogenization treatment.Attention: The homogenate should be sufficient, otherwise it will affect RNA production.2. Centrifuge the solution obtained in the previous step at 12000 rpm (~13400 × g) for 3-5 minutes. Carefully add the supernatant to the spin columns DM that have been loaded into the collection tube. Centrifuge at 12000 rpm for 30-60 seconds and collect the filtrate. Place the adsorption column DM in a new 2 ml collection tube at room temperature or 4 ℃ for DNA extraction. Attention: Ensure that there is no liquid residue on the adsorption column, and if necessary, repeat centrifugation until all liquids pass through the membrane of the adsorption column. Total RNA extraction3. Add 1 volume of 70% ethanol (prepared without RNase water) to the filtrate obtained in step 2, and mix well.4. Add all the solution obtained in the previous step to the spin columns RM that have been loaded into the collection tube. If the solution cannot be added completely at once, it can be transferred in stages. Centrifuge at 12000 rpm for 20 seconds and retain the liquid in the collection tube for protein extraction.5. Place the adsorption column RM into a new 2ml collection tube and add 700 to the adsorption column RM µ L Buffer RW1, centrifuge at 12000 rpm for 20 seconds, discard the waste liquid in the collection tube, and place the adsorption column RM into the recovery manifold.6. Add 500 to the adsorption column RM µ Buffer RW2 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 20 seconds, discard the waste liquid in the collection tube, and place the adsorption column RM back into the 2 ml collection tube.7. Repeat step 6.Centrifuge at 8.12000 rpm for 2 minutes and discard the waste liquid from the collection tube. Place the adsorption column at room temperature for a few minutes to thoroughly air dry. Attention: The purpose of this step is to remove residual ethanol from the adsorption column, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).9. Place the adsorption column RM in a new 1.5 ml centrifuge tube without RNase, and add 30-50 to the middle of the adsorption column RM µ Place RNase Free Water at room temperature for 2-5 minutes, centrifuge at 12000 rpm for 1 minute, collect RNA solution, and store RNA at -70 ℃ to prevent degradation.Attention:1) The volume of RNase Free Water should not be less than 30 µ l. Small volume affects the recovery rate.2) If you want to increase RNA production, you can use 30-50 µ Repeat step 9 for the new RNase Free Water.3) If you want to increase the RNA concentration, you can add the obtained solution back to the adsorption column and repeat step 9.Genomic DNA extraction10. Add 500 to the adsorption column DM µ Buffer GW1 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 20 seconds, discard the waste liquid in the collection tube, and place the adsorption column DM into the recovery tube.11. Add 500 to the adsorption column DM µ Buffer GW2 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 2 minutes, discard the waste liquid in the collection tube, and place the adsorption column DM into the recovery tube. Attention: To further improve DNA purity, repeat step 11.Centrifuge at 12.12000 rpm for 2 minutes and discard the waste liquid from the collection tube. Place the adsorption column DM at room temperature for a few minutes to thoroughly dry the ethanol in the column. Attention: The purpose of this step is to remove residual ethanol from the adsorption column, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).13. Place the adsorption column DM in a new centrifuge tube and add 100 to the middle of the adsorption column DM by suspending it in the air µ L Buffer GE, leave at room temperature for 2-5 minutes, centrifuge at 12000 rpm for 2 minutes, collect DNA solution, and store DNA at -20 ℃.Attention:1) The volume of Buffer GE should not be less than 100 µ l. Small volume affects the recovery rate.2) If we want to increase DNA production, we will µ Add a new Buffer GE to the adsorption column and repeat step 13; If you want to increase the DNA concentration, you can add the DNA eluent obtained in step 13 back onto the adsorption column and repeat step 13.Protein extraction14. Add 1 volume of Buffer PZ to the RNA extraction effluent (i.e. the solution obtained in step 4), mix well, and let it stand at room temperature for 10-30 minutes.Centrifuge at 15.12000 rpm for 10 minutes and discard the supernatant.16. Add 500 µ Centrifuge at 12000 rpm for 1 minute with 70% ethanol, and try to absorb the supernatant as much as possible.17. Place the centrifuge tube at room temperature for a few minutes to dry the precipitate.Attention: The purpose of this step is to remove residual ethanol. Excessive drying can make protein precipitation difficult to dissolve, and incomplete drying of residual ethanol can affect protein loading.18. Add 100 µ L Buffer PLS to obtain protein solution.Attention:1) The protein samples obtained by dissolving with Buffer PLS are suitable for SDS-PAGE and Western Blot detection, but not for Bradford method for protein quantification. If Bradford method is needed for protein quantification, 5% SDS can be used to dissolve the protein, or suitable protein dissolution buffer can be selected based on downstream experiments.2) The amount of dissolved protein buffer added is determined based on the initial sample size and specific downstream test requirements.3) The dissolved protein can be stored at -20 ℃ for several months and at 2-8 ℃ for several days.If protein samples require SDS-PAGE electrophoresis, the following operations can be performed:19. Add protein loading buffer to the protein sample, denature at 95 ℃ for 5-10 minutes, and cool the sample to room temperature. Centrifuge at 20.12000 rpm for 1 minute, extract the supernatant for downstream SDS-PAGE or Western blot tests... Read More | Lipid peroxidation is the degradation of lipids that occurs as a result of oxidative damage and is a useful marker for oxidative stress. Polyunsaturated lipids are susceptible to an oxidative attack, typically by reactive oxygen species, resulting in a well-defined chain reaction with the productionLipid peroxidation is the degradation of lipids that occurs as a result of oxidative damage and is a useful marker for oxidative stress. Polyunsaturated lipids are susceptible to an oxidative attack, typically by reactive oxygen species, resulting in a well-defined chain reaction with the production of end products such as malondialdehyde (MDA). Lipid peroxidation may contribute to the pathology of many diseases including atherosclerosis, diabetes, and Alzheimer′s.Lipid peroxidation (MDA) assay kit has been used to determine the levels of malondialdehyde (MDA).Suitability: Suitable for the measurement of malondialdehyde (MDA) in a variety of samples including tissue, cells and plasmaPrinciple: In this kit, lipid peroxidation is determined by the reaction of MDA with thiobarbituric acid (TBA) to form a colorimetric (532 nm)/fluorometric (λex= 532/λem= 553 nm) product, proportional to the MDA present... Read More | Product content: M665794Component125 TStorageM665794A2×miRNA qPCR Mixture (ROX)2×750 µL-20℃. Avoid freeze/thaw cycleM665794BReverse Primer, 10 µM60 µL-20℃. Avoid freeze/thaw cycleM665794CddH2O1.5 mL-20℃. Avoid freeze/thaw cycle Product Introduction:This kitProduct content: M665794Component125 TStorageM665794A2×miRNA qPCR Mixture (ROX)2×750 µL-20℃. Avoid freeze/thaw cycleM665794BReverse Primer, 10 µM60 µL-20℃. Avoid freeze/thaw cycleM665794CddH2O1.5 mL-20℃. Avoid freeze/thaw cycle Product Introduction:This kit uses the principle of SYBR Green I chimeric fluorescent dye method for miRNA fluorescence quantitative PCR detection. The kit includes 2 x miRNA qPCR Mixture and Reverse Primer required for detection. 2 x miRNA qPCR Mixture is a new generation pre mixed form of fluorescence quantitative PCR detection reagent specially developed for miRNA quantitative detection. The fluorescent dye SYBR Green I contained in it can bind to all double stranded DNA, making the product suitable for detecting different target sequences without the need to synthesize specific labeled probes. The GoldStar Taq DNA polymerase is a chemically modified and highly efficient thermal starter enzyme, coupled with a unique buffer system, which enhances reaction specificity, sensitivity, and enables accurate quantification of miRNA over a wider range. The 2x miRNA qPCR Mixture contains ROX dye and is suitable for fluorescence quantitative PCR instruments that require ROX as a calibration dye.Note: This kit must be used in conjunction with the miRNA cDNA first strand synthesis kit.Self prepared experimental materials: qPCR upstream primer.Forward Primer design principles:1. Follow the most common principles of primer design.2.Based on mature miRNA sequences, replacing U with T is the most basic and simplest design method.3.The Tm value of the downstream primer provided in the reagent kit is 63.6 ℃, and the Tm value of the upstream primer should be designed to be around 63.6 ℃ as much as possible.4. If the Tm value of the primer directly designed according to principle "2" is too low, several bases (preferably G or C bases) can be added to the 5 'end of the primer; One or several A bases can also be added at the 3 'end; Alternatively, both the 5 'and 3' ends can be modified simultaneously.5.If the Tm value of a primer designed directly according to principle "2" is too high, several bases can be removed from the 5 'or 3' end of the primer.Notes:1. Before using the reagent, please gently mix it upside down to avoid foaming, and use it after a brief centrifugation.2. The amount of miRNA first strand cDNA added should not exceed 10% of the volume of Real time PCR.3. For special detection systems, high content of cDNA templates can easily lead to non-specific amplification. Dilute cDNA appropriately (10 or 100 times dilution) based on the abundance of detected miRNAs.4. The 2x miRNA qPCR Mixture in this product contains SYBR Green I and ROX dyes. When storing this product or preparing PCR reaction solution, strong light exposure should be avoided.5. Avoid repeated freezing and thawing of this product. Repeated freezing and thawing may cause a decrease in product performance. This product can be stored at -20 ℃ for long-term storage. If frequent use is required in the short term, the 2xmiRNA qPCR Mixture can be stored at 2-8 ℃. However, the Reverse primer still needs to be stored at -20 ℃.Operation steps:1. Melt 2 x miRNA qPCR Mixture and Reverse Primer at room temperature (10 µ M). 2. When using, please gently mix the 2x miRNA qPCR Mixture upside down to avoid foaming, and use after brief centrifugation. If the reagent is not well mixed, its reaction performance will decrease.3. Place the reagent on ice and prepare the reaction system according to the following table: reagent volume final concentration 2×miRNA qPCR Mixture（ROX） 10 µl 1× Forward primer（10 µM） 0.4µl 0.2 µM Reverse primer（10 µM） 0.4µl 0.2 µM MiRNA first strand cDNA X µl — ddH2O up to 20 µl —4. The reaction program is set as follows:Attention!The pre denaturation reaction of this product must be completed at 95 ℃ for 10 minutes! Note: 1) The hot start enzyme used in this product must be activated under pre denaturation conditions of 95 ℃ and 10 minutes.2) The annealing temperature should be set at 60-64 ℃ as a reference range. When non-specific reactions occur, the annealing temperature can be increased... Read More | Product content: S665546Component50 TStorageS665546ABuffer QSL45 mLRTS665546BBuffer RIL11 mL2-8℃S665546CBuffer ML10 mLRTS665546DBuffer GW1 (concentrate)13 mLRTS665546EBuffer GW2 (concentrate)26 mLRTS665546FBuffer EBL13 mLRTS665546GRNase A240 µLRTS665546HLysis Tubes Ⅱ50 Product content: S665546Component50 TStorageS665546ABuffer QSL45 mLRTS665546BBuffer RIL11 mL2-8℃S665546CBuffer ML10 mLRTS665546DBuffer GW1 (concentrate)13 mLRTS665546EBuffer GW2 (concentrate)26 mLRTS665546FBuffer EBL13 mLRTS665546GRNase A240 µLRTS665546HLysis Tubes Ⅱ50 EARTS665546ISpin Columns DM With Collection Tubes50 EARTProduct IntroductionThis kit provides a method for extracting total DNA from soil or fecal samples, including the total DNA of cells, bacteria, parasites, and viruses in the samples. It is also suitable for extracting DNA from samples containing high concentrations of PCR reaction inhibitors. This reagent kit adopts a unique buffering system to efficiently bind DNA from the lysis solution to the adsorption column. Inhibitors of PCR and enzyme reactions, as well as residual impurities, can be effectively removed through washing steps. Finally, high-purity DNA can be obtained by washing with low salt buffer or water. The purified DNA can be directly used for downstream experiments such as second-generation sequencing (16S amplicons and metagenomes), library construction, PCR, qPCR, Southern Blot, enzyme digestion molecular markers, etc.Self prepared reagents1. Constant temperature mixer - Product number: CW25932. Anhydrous ethanol, isopropanol3. Vortex oscillator or tissue grinderPreparation and important precautions before the experiment1. Samples should avoid repeated freeze-thaw cycles, otherwise it may result in smaller extracted DNA fragments and a decrease in extraction volume.2.Before the first use, anhydrous ethanol should be added to Buffer GW1 (concentrate) and Buffer GW2 (concentrate) according to the instructions on the reagent bottle label.3. Take out the buffer RIL before use and store it at 2-8 ℃ immediately after use.Operation steps1. Centrifuge the Lysis Tube briefly to allow the beads to settle at the bottom.2. a. Add 0.1-0.3 g of soil or fecal sample to Lysis Tube, and add 740-820 µ L Buffer QSL and 4 µ L RNase A, tighten the tube cover and briefly vortex to mix.b. If fecal samples are stored in non lytic fecal preservation solutions (such as CWY041S and CWY041M), add 200 to Lysis Tube µ L-600 µ L solid-liquid mixture, centrifuge at 13000 rpm for 1 minute, discard the storage solution (if the amount of solid after centrifugation is too small, it can be enriched again, but should not exceed 0.3g). Join 620 µ LBuffer QSL and 4 µ L RNase A, tighten the tube cover and briefly vortex to mix.3. Fix the Lysis Tube in an oscillating grinding device equipped with a 2 mL adapter and process it according to the optimized grinding conditions of your equipment (see appendix).4. Shake the Lysis Tube on a constant temperature mixer at 70 ℃ and 1200 rpm for 10 minutes. Subsequently, centrifuge at 13000 rpm for 2 minutes to precipitate solid particles. Transfer 540 µ Transfer the supernatant to a new 2 mL centrifuge tube.5. Add 180 µ L Buffer RIL, vortex for 5 seconds, centrifuge at 13000 rpm for 2 minutes.Attention: Remove the buffer RIL before use and store it at 2-8 ℃ immediately after use.6. Add 160 to the new centrifuge tube in sequence µ L Buffer ML, 480 µ Supernatant from step 5, 320 µ L isopropanol, vortex for 5 seconds.7. Transfer the solution from the previous step to 650 µ Centrifuge at 12000 rpm (~13400 × g) for 1 minute into the spin columns DM that have been loaded into the collection tube.8. Discard the waste liquid in the collection pipe and place the adsorption column back into the collection pipe. Repeat step 7 until all the solution has been transferred.9. Add 500 to the adsorption column µ L Buffer GW1 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube.10. Add 500 to the adsorption column µ L Buffer GW2 (check if anhydrous ethanol has been added before use), centrifuge at 12000 rpm for 1 minute, discard the waste liquid in the collection tube, and place the adsorption column back into the collection tube. 11. Repeat step 10.12.12000 rpm for 2 minutes and discard the waste liquid from the collection tube. Place the adsorption column at room temperature for a few minutes to thoroughly air dry.Note: The purpose of this step is to remove residual ethanol from the adsorption column, which can affect subsequent enzymatic reactions (such as enzyme digestion, PCR, etc.).13. Place the adsorption column in a new centrifuge tube (self provided) and add 50-200 drops of suspended droplets to the middle of the adsorption column µ L Buffer EBL or sterilized water, leave at room temperature for 2-5 minutes, centrifuge at 12000 rpm for 1 minute, collect DNA solution, and store DNA at -20 ℃.Note: 1) Incubating at room temperature for 5 minutes before centrifugation can increase yield.2) Use an additional 50-100 µ Further elution with L buffer or sterilized water can increase yield.3) If you want to increase the final concentration of DNA, you can add the DNA eluent obtained in step 13 back onto the adsorption membrane and repeat step 13, but it may reduce the total yield.4) The elution buffer does not contain chelating agents, please store DNA at -20 ℃.5) The residual trace PCR inhibitors in the genomic DNA template may have adverse effects on the PCR reaction, which can usually be resolved by diluting the DNA by 2-10 times.Appendix: Grind the sample using one of the following methods1. Manually vortex oscillate at maximum speed on the vortex oscillator for 10 minutes.2. On a vortex oscillator equipped with a 1.5-2 mL horizontal centrifuge tube holder, oscillate at maximum speed for 10 minutes (keeping the Lysis Tube horizontal). If the sample size exceeds 12, extend by 5-10 minutes. For example, using Scientific Industries or Mobile's Vortex Genie2 vortex oscillator.3.When using Qiagen's TissueLyser II, grind at 25Hz for 10 minutes.4.When using Qiagen's PowerLyzer 24 Homogenizer, homogenize at 2000 rpm for 30 seconds, pause for 30 seconds, and then homogenize again at 2000 rpm for 30 seconds.5.When using FastPrep-24 from MP Biomedicals, the recommended speed is 6.0 and the time is 40 seconds... Read More | Component Description T665563Component50 TStorageApplicationT665563AVNTR3820 1 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563BVNTR41201 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563CVNTR32321 mL-20℃. Avoid freeze/thaw Component Description T665563Component50 TStorageApplicationT665563AVNTR3820 1 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563BVNTR41201 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563CVNTR32321 mL-20℃. Avoid freeze/thaw cycle.High resolution 3-lite VNTR detectionT665563DMarkerⅠ300 µL-20℃. Avoid freeze/thaw cycle.DNA Molecular Weight Standard IT665563EMarkerⅡ250 µL-20℃. Avoid freeze/thaw cycle.DNA Molecular Weight Standard IIProduct IntroductionThis kit is a genotyping product for human Mycobacterium tuberculosis based on the latest research progress in molecular epidemiology1) and optimized by process. It utilizes variable-number tandem repeats (VNTR) polymorphisms in the Mycobacterium tuberculosis genome for genotyping to differentiate clinical strains, and is a powerful tool for studying the molecular epidemiology of Mycobacterium tuberculosis and monitoring the status of tuberculosis transmission. Compared with other existing Mycobacterium tuberculosis VNTR typing systems based on the VNTR principle, this typing system has a stronger ability to discriminate strains prevalent in China1,2,3), and is therefore particularly suitable for the needs of Chinese users.By carefully optimizing the primer sequences of each PCR reaction and the composition of the premixed reaction solution, this product has a strong anti-interference power. Compared with the user's own reagents, this product significantly improves the signal intensity of specific bands and reduces the appearance of non-specific bands when using crude templates (boiling bacterial solution), which makes the experimental operation easier and quicker, and at the same time, improves the success rate of the test. The premixed reaction solution is chemically stable and can effectively withstand repeated freezing and thawing (10 times) and a longer period of time (one week) at room temperature, which is better adapted to the user's need for flexibility in the detection work.This kit is a companion product to the TB Genotyping Kit VNTR-9. For samples identified as clustered or identical strains by the VNTR-9 kit, this product can be used for finer further typing identification if necessary. The three high-resolution detection sites VNTR3820, VNTR4120 and VNTR3232 in this product can be used in combination with the nine detection sites in the VNTR-9 to increase the resolution index (Hunter-Gaston index (HGI) to 0.9931).References1) Luo T et al. Development of a hierarchical variable-number tandem repeat typing scheme for Mycobacterium tuberculosis in China. PLoS One. 2014 Feb 25. 9(2)2)Sun G et al. Discriminatory potential of a novel set of Variable Number of Tandem Repeats for genotyping Mycobacterium marinum. Vet Microbiol. 2011 Aug Vet Microbiol. 2011 Aug 26;152(1-2)3) Zhang L et al. Highly polymorphic variable-number tandem repeats loci for differentiating Beijing genotype strains of Mycobacterium tuberculosis in Shanghai, China. FEMS Microbiol Lett. 2008 May;282(1):22-31.matters needing attention1.This product is a companion to the TB genotyping kit VNTR-9. The strains to be tested should be tested by VNTR-9 typing test first, and then use this product for testing. And the results of this product should be integrated and analyzed with the results of VNTR-9.2.To avoid contamination, it is recommended that the preparation of the organisms be done within a different location than the preparation of the PCR Mix and that different pipettes be used.3.Care should be taken at all stages of sample DNA collection, extraction and amplification to ensure proper labeling and to prevent cross-contamination between different samples.4.Commonly used reagents and consumables need to be autoclaved before experimentation.5.Each tube of PCR Mix contains different primers and cannot be mixed. It can be dispensed into different amounts at once according to the experimental needs to avoid repeated freezing and thawing.6.To avoid splashing the reaction solution when opening the reaction tube, centrifuge briefly before opening the cap and collect the liquid at the bottom of the tube. In case of accidental splashing on gloves or table, change gloves immediately and wipe the table with 75% alcohol or dilute acid.7.Be careful not to cross-contaminate the PCR Mix when aspirating, and it is recommended that the pipette tip be wiped with 75% alcohol 2 times before taking Mix each time.8.Pre-experiment preparation: 1×TE buffer (PH=8.0), 0.5×TBE buffer, agarose, ethidium bromide (EB), normal PCR instrument, DNA electrophoresis equipment and gel imager, 0.2 ml PCR reaction tubes, octuplex or 96-well PCR tubes, pipettes of different sizes: 0.5-10 µl and 20-200 µl.Operation steps1. DNA template preparation:1.1. scrape a small amount (1-2 inoculation loops) of sample from solid medium, resuspend in 100ul TE and inactivate at 80°C for 30 minutes.1.2. The inactivated strain was taken out of the P3 laboratory as follows:Boil at 100°C for 10 minutes (be careful to avoid bursting the cap of the EP tube during boiling to avoid letting water into the tube), place immediately on ice for 2 minutes, centrifuge at 12,000 rpm (~13,400 × g) for 10 minutes, take the supernatant and place in another sterile EP tube, label it, and store at -20°C.2. Testing procedures:2.1. Remove the TB Genotyping Kit HV-3, allow the liquid to equilibrate to room temperature, mix by shaking slightly 3-4 times, and then centrifuge at 12,000 rpm (~13,400 x g) for 5 seconds to allow the capped liquid to fall back into the tube.2.2.Three-locus VNTR typing: strains with identical results at 12 loci need to be further VNTR typed, i.e., the following four loci are added for comparison.1）PCR amplification: the reaction system was 20 µl. 19 µl of PCR Mix of VNTR3820, VNTR4120, and VNTR3232 were added to each PCR tube, 1 µl of DNA template was added, and mixed well.2）Amplification conditions:3) Gel preparation and electrophoresis:a: Notes:Important! Positive (H37Rv strain DNA) and negative controls (deionized water) need to be set up for each experiment.Key! This experiment is based on agarose gel electrophoresis to interpret the genotype of VNTR locus, therefore, in order to make the results accurate, it is necessary to follow the unified standard operation in this step of electrophoresis, and the following points should be noted:a-1: The comb used for glue making is 18 holes.a-2: The two wells on the left and right sides of the gel were discarded due to the tendency to distort the bands during electrophoresis, affecting the interpretation of the results, or a negative control was spotted in one of the wells. The remaining 16 wells were divided into 12 samples, 3 DNA Markers and 1 positive control. The order of spotting was "1, 2, M, 3, 4, 5, 6, M, 7, 8, 9, 10, M, 11, 12, H37Rv", the numbers represent samples, and M represents DNA Marker.a-3: When PCR amplification products are subjected to the first electrophoresis and Marker I is used, the gel concentration is 1%, the voltage is 150 V, and the time is 100-120 min.a-4: If the amplification product fragment is too large (>1000bp) and needs to be electrophoresed again and Marker II is used, the gel concentration is 0.8%, the voltage is 150V and the time is 150 minutes.b: Gluing as well as the electrophoresis process:PCR amplification products were electrophoresed using a 1% agarose gel.To prepare 1% agarose gel, 12×12 cm gel tray was used to make the gel, each gel was 80 ml.b-1: Weigh 0.8g of agarose, add 80ml of 0.5×TBE, weigh it on the balance and put it into the microwave oven, heat it on high for 2-3 minutes to make the agarose dissolve completely, shake it well, and observe it as a homogeneous and transparent solution without particles, then weigh it again on the balance and make up the appropriate amount of double-distilled water to keep the concentration of the gum unaffected.b-2: When the melted gel was cooled to about 55°C add 4 µl of ethidium bromide (10ug/ml) and gently swirl to mix well. The gel was made with an 18-tooth comb and the warm gel was poured into a 12 × 12 cm gel tray.b-3: Allow the gel to completely set (40 minutes at room temperature), carefully pull out the comb, remove the tray, and place it in the electrophoresis tank. Add 0.5× TBE buffer to the electrophoresis tank, not exceeding the gel surface by 1-2mm.b-4: Sample electrophoresis: add 12 samples to each gel (the topmost wells are not sampled), add 3-5µl PCR products to each well, and at the same time add three 5µl DNA MarkerⅠ to each gel. The voltage is 150V and the electrophoresis time is 100-120 minutes. This step is the key to the accuracy of the final readings of each point, and needs to be operated uniformly according to this standard.b-5: Some loci have amplification products greater than 1000bp in clinical strains, and these amplification products were then electrophoresed using 0.8% agarose gel, with DNA Marker II added as a control for the band size, voltage 150V, electrophoresis time 150 minutes.4) Results display:5) Analysis of results:a. If the genotypes of the three highly variable loci are also the same in different strains, they can be identified as clustered strains;b. If the high variant readings are highly similar, i.e., only 1-2 high variant sites are different, they need to be combined with epidemiologic data to identify if they are clustered strains;c. If all 3 high variant loci are genotypically discordant, identify as a single strain.Appendix 1: Rules for reading VNTR lociAppendix 2: VNTR locus repeat unit readout table... Read More |