| Description | Aladdin's E. coli DNA Polymerase I purified using the PerfectProtein™ technology platform developed by aladdin, catalyzes the the 5'→3' polymerization of deoxyribonucleotides in a DNA template-dependent manner [1]. It also possesses dsDNA nick-specific 5'→3' exonuclease activity, Aladdin's E. coli DNA Polymerase I purified using the PerfectProtein™ technology platform developed by aladdin, catalyzes the the 5'→3' polymerization of deoxyribonucleotides in a DNA template-dependent manner [1]. It also possesses dsDNA nick-specific 5'→3' exonuclease activity, ssDNA-specific 3'→5' exonuclease activity, and RNase H activity [2]. The DNA synthesis activity and dsDNA nick-specific 5'→3' exonuclease activity allow for DNA synthesis starting from a 3'-OH group at the nick and degradation of single-stranded DNA at 5' end, facilitating gap filling. Its ssDNA-specific 3'→5' exonuclease activity serves a proofreading function during DNA synthesis. In the presence of dNTP, the E. coli DNA Polymerase I primarily exhibits DNA polymerase activity, while in the absence of dNTP, it displays more ssDNA-specific exonuclease activity, such as 5'→3' exonuclease activity on either strand at the 5' end of a blunt-ended dsDNA.The versatility of E. coli DNA Polymerase I allows it to initiate the synthesis of new DNA chains from gaps or nicks in dsDNA, and to degrade the DNA strand complementary to the template strand from the nick, enabling nick translation. It also ensures proofreading of mismatch during DNA replication and fills in gaps that occur during replication and repair processes [3].Please refer to Figure 1 for the performance of this product in filling 5' overhangs of dsDNA.Figure 1. Performance of Aladdin's E. coli DNA Polymerase I in filling 5' overhangs of dsDNA. In a 20µl reaction (10mM Tris-HCl, 50mM NaCl, 10mM MgCl2, 1mM DTT, 100µM dNTP Mix, 0.5µM dsDNA with 5' overhang, pH 7.9 at 25℃), the specified amount of this product or E. coli DNA Polymerase I from Company N (Competitor) was added. After incubation at 37℃ for 20 minutes, reactions were terminated by incubation at 75℃ for 20 minutes, followed by 15% native PAGE analysis of 5µl of the reaction product after mixing with 1µl of 6X DNA Loading Buffer. Electrophoresis was conducted at 180V for 60 minutes, and then the gel was stained with Gel-Red (10000X) at room temperature for 5 minutes. The experimental results were observed under a UV lamp. As shown in the figure, this product has similar catalytic efficiency to Competitor. The substrate dsDNA with 5' overhang was obtained by annealing 5'-ATACATAGATACATAGACTGGCCGTCGTTTTAC-3' and 5'-GTAAAACGACGGCCAGT-3' using Annealing Buffer for DNA Oligos (5X) according to manufacture's instructions. This figure is for reference only, which may vary due to different experimental conditions.Please refer to Figure 2 for performance of this product in digesting double-stranded linear DNA with amino-modified 3' ends.Figure 2. Performance of Aladdin's E. coli DNA Polymerase I in digesting amino-modified 3' ends of dsDNA (5'→3' exonuclease activity). In a 20µl reaction (10mM Tris-HCl, 50mM NaCl, 10 mM MgCl2, 1mM DTT, 0.5µM dsDNA), the specified amount of this product or E. coli DNA Polymerase I from Company N (Competitor) was added. After incubation at 37℃ for 20 minutes, reactions were terminated by incubation at 75℃ for 20 minutes, followed by 15% native PAGE analysis of 5µl of the reaction product after mixing with 1µl of 6X DNA Loading Buffer. Electrophoresis was conducted at 180V for 60 minutes, and then the gel was stained with Gel-Red (10000X) at room temperature for 5 minutes. The experimental results were observed under a UV lamp. As shown in the figure, this product has similar catalytic efficiency to Competitor. The substrate dsDNA with amino-modified 3' ends was obtained by annealing 5'-ATACATAGATACATAGACTGGCCGTCGTTTTAC-3'NH2 and 5'-GTAAAACGACGGCCAGTCTATGTATCTATGTAT-3'NH2 using Annealing Buffer for DNA Oligos (5X) according to manufacture's instructions. This figure is for reference only, which may vary due to different experimental conditions.sApplication：DNA synthesis; complementary filling of dsDNA 5' overhangs; removal of dsDNA 3' overhangs; second strand cDNA synthesis [4]; in combination with DNase I for DNA nick translation; nick translation to obtain probes with high specific activity.Source：Purified from E. coli with recombinant expression of E. coli DNA Polymerase I.Enzyme storage buffer：25mM Tris-HCl, 1mM DTT, 0.1mM EDTA, 50% Glycerol (pH 7.4 at 25 ℃).Inactivation or inhibition：This product can be inactivated by incubation at 75℃ for 20 minutes.Precautions：Due to the exonuclease activity of E. coli DNA Polymerase I, please avoid high environmental temperatures before performing the reaction. Otherwise, the DNA strands may be cleaved.E. coli DNA Polymerase I does not possess endonuclease activity, nor DNase I either. Therefore, when performing nick translation reactions, DNase I must be added.Vigorous shaking or stirring of E. coli DNA Polymerase I can cause enzyme inactivation.E. coli DNA Polymerase I has a high affinity for DNA. Addition of excessive amount of enzyme may lead to aggregation, thus affecting the amplification reactions.E. coli DNA Polymerase I can polymerize deoxyribonucleotides labeled with biotin, digoxigenin, or fluorescence, etc, allowing for synthesis of labeled DNA probes.The enzyme should be kept on ice during use, and stored at -20℃ immediately after use.This product is for R&D only. Not for drug, household, or other uses.For your safety and health, please wear a lab coat and disposable gloves during the operation.Instructions for Use：1. Fill-in of 5' overhangs of dsDNAa. Set up the following reaction on ice.ReagentVolumeFinal ConcentrationNuclease-free Water(16-x)µl-dsDNA with 5' overhangsxµl~0.5µM or 5-200ng/µl10X Reaction Buffer2µl1XdNTP Mix (2mM each)1µl100µME.coli DNA Polymerase I (10U/µl)1µl0.5U/µlTotal Volume20µl-Note 1: The enzyme amount can be reduced appropriately to avoid template cleavage due to its exonuclease activity.Note 2: When multiple reactions are required, prepare a master mix including all reagents except for dsDNA, and then dispense to different nuclease-free PCR tubes. Finally, add dsDNA template to each tube.Note 3: If the dsDNA with 5' overhangs are oligonucleotides, the final concentration can be approximately 0.5µM. However, for digested DNA plasmids, the final concentration can be approximately 5-200ng/µl.b. Mix well gently and then have a pulse-spin in a microfuge to collect the liquid at the bottom of the tube.c. Incubate at 37℃ for 20 minutes. Note: The reaction time can be adjusted based on actual situations.d. Incubate at 75℃ for 20 minutes to inactivate the E. coli DNA Polymerase I.2. Digestion of Double-stranded Linear DNAa. Set up the following reaction on ice.ReagentVolumeFinal ConcentrationNuclease-free Water(17-x)µl-dsDNAxµl~0.5µM or 5-200ng/µl10X Reaction Buffer 2µl1XE.coli DNA Polymerase I (10U/µl)1µl0.5U/µlTotal Volume20µl-Note: When multiple reactions are required, prepare a master mix including all reagents except for dsDNA, and then dispense to different nuclease-free PCR tubes. Finally, add dsDNA to each reaction tube.b. Mix well gently and then have a pulse-spin in a microfuge to collect the liquid at the bottom of the tube.c. Incubate at 37℃ for 20 minutes. Note: The reaction time can be adjusted based on actual situations.d. Incubate at 75℃ for 20 minutes to inactivate E. coli DNA Polymerase I.3. For other applications, please refer to appropriate literature.FAQ:1. Can the E. coli DNA Polymerase I fill in 3' overhangs?No, E. coli DNA Polymerase I cannot fill in 3' overhangs. It can only generate blunt ends by removing 3' overhangs. 's E. coli DNA Polymerase I, Klenow Fragment, and T4 DNA Polymerase can be used for fill-in of 3' overhangs.2. Can E. coli DNA Polymerase I fill in 5' overhangs of DNA?Yes, E. coli DNA Polymerase I can fill in 5' overhangs of dsDNA. Klenow Fragment (, D7037) lacks 5'→3' exonuclease activity and is recommended for fill-in of 5' overhangs.3. Can E. coli DNA Polymerase I be used for nick translation experiments?Yes, nick translation experiments are one of the important applications of E. coli DNA Polymerase I.4. Are there temperature requirements for nick translation experiments?The incubation temperature for nick translation experiments should be below 20℃. At higher temperatures, the newly synthesized DNA can separate and be replicated.5. Can E. coli DNA Polymerase I be heat-inactivated?Yes, this product can be inactivated by heating at 75℃ for 20 minutes. Addition of 10mM EDTA to chelate Mg2+ before performing heat-inactivation can protect the DNA ends. 6. Can E. coli DNA Polymerase I remove 5' overhangs?No, the 5'→3' exonuclease activity of this product is only applicable to gaps in dsDNA.7. Can DNA nick translation be used for labeling probes?Yes, this product can remove template bases at nicks using its 5'→3' exonuclease activity and fill in nicks with labeled nucleotides. This method is suitable for generating large and uniform probes, but with lower efficiency probably.References:1. Kunkel TA, Loeb LA, Goodman MF. J Biol Chem. 1984. 259(3):1539-45.2. Green MR, Sambrook J. Cold Spring Harb Protoc. 2020. 2020(5):100743.3. Yu H, Chao J, Patek D, Mujumdar R, Mujumdar S, Waggoner AS. Nucleic Acids Res. 1994. 22(15):3226-32.4. D'Alessio JM, Gerard GF.Nucleic Acids Res. 1988. 16(5):1999-2014... Read More | Ganglioside GT1b is a brain ganglioside. It is composed of a neutral tetra-saccharide core, with one or two sialic acid on the internal galactose and an extra sialic acid on the non-reducing terminal of galactose | The Leuconostoc GPDH exhibits dual coenzyme specificity, namely NAD and NADP (Olive and Levy, Biochem., 6, 730 730, 1967). When assayed under conditions that are optimal for the particular coenzyme, the ratio of observed catalytic activity is NAD/NADP = 1.8 | SHP2 protein degrader-2 (SHP2-D26) is a SHP2 protein PROTAC degrader. SHP2 protein degrader-2 reduces expression level of SHP2 in various cancer cells.In VitroSHP2 protein degrader-2 (SHP2-D26) achieves excellent degradation of SHP2 with the DC 50 (the concentration where 50% of the protein has beenSHP2 protein degrader-2 (SHP2-D26) is a SHP2 protein PROTAC degrader. SHP2 protein degrader-2 reduces expression level of SHP2 in various cancer cells.In VitroSHP2 protein degrader-2 (SHP2-D26) achieves excellent degradation of SHP2 with the DC 50 (the concentration where 50% of the protein has been degraded) values of 2.6 nM and 6.0 nM for MV4;11 and KYSE520 cells, respectively. MCE has not independently confirmed the accuracy of these methods. They are for reference only.Form:Solid... Read More | Vabicaserin hydrochloride is a 5-hydroxytryptamine 2C ( 5-HT 2C ) receptor -selective agonist with an EC 50 of 8 nM.In VitroVabicaserin displaces 125 I-(2,5-dimethoxy)phenylisopropylamine binding from human 5-HT 2C receptor sites in Chinese hamster ovary cell membranes with a K i value of 3 nM and Vabicaserin hydrochloride is a 5-hydroxytryptamine 2C ( 5-HT 2C ) receptor -selective agonist with an EC 50 of 8 nM.In VitroVabicaserin displaces 125 I-(2,5-dimethoxy)phenylisopropylamine binding from human 5-HT 2C receptor sites in Chinese hamster ovary cell membranes with a K i value of 3 nM and is >50-fold selective over a number of serotonergic, noradrenergic, and dopaminergic receptors. Binding affinity determined for the human 5-HT 2B receptor subtype using [ 3 H]5HT is 14 nM. Vabicaserin is a potent and full agonist (EC 50, 8 nM; E max, 100%) in stimulating 5-HT 2C receptor-coupled calcium mobilization and exhibits 5-HT 2A receptor antagonism and 5-HT 2B antagonist or partial agonist activity in transfected cells, depending on the level of receptor expression. Vabicaserin exhibits lower affinity at the 5-HT 2C antagonist binding site (22 nM) labeled with [ 3 H]mesulergine. Additional binding studies indicate that Vabicaserin possesses affinity for the 5-HT 2B and 5-HT 1A receptors with K i values of 14 and 112 nM, respectively. MCE has not independently confirmed the accuracy of these methods. They are for reference only.In VivoAfter a single oral dose of [ 14 C]Vabicaserin at 50, 5, and 15 mg/kg, unchanged drug represents less than 19, 20, and 35% of total plasma radioactivity at all the time points examined in mice, rats, and dogs, respectively. The carbamoyl glucuronide (CG) represents approximately 7 to 36% of plasma radioactivity in mice and 2 to 28% of plasma radioactivity in dogs but is not detected in rat plasma after the single [ 14 C]Vabicaserin dose. However, the CG is observed in rat plasma after multiple-dose administration of Vabicaserin at higher doses, and the CG is approximately 20 times less than Vabicaserin based on steady-state AUC 0-24 values. The estimated plasma AUC 0-24 ratios of CG to the parent drug are 1.5 and 1.7 in mice and dogs after the single [ 14 C]Vabicaserin dose, respectively. The plasma AUC 0-24 ratios for the CG to Vabicaserin at steady state with doses used for safety assessment are less for mice (0.2-0.6) and slightly higher for dogs (1.8-4.0) compared with the single dose values. The CG is detected in dog urine in similar amounts to the parent drug, although it is not detected in mouse or rat urine after the single [ 14 C]Vabicaserin dose. Radioactivity in a 0- to 24-h bile collection from rats receiving a 5 mg/kg [ 14 C]Vabicaserin dose accounts for 19 and 24% of the administered dose in males and females, respectively. Although the CG is not detected in urine or feces of rats after a single oral administration, it represents an average of up to 30% of biliary radioactivity in male rats and 15% in female rats. In monkeys after a single oral 25-mg/kg dose of Vabicaserin, the plasma concentrations of the CG exceeded those of Vabicaserin at all the time points (2-24 h) postdose, although the amount of CG relative to Vabicaserin decreased by 24 h postdose, with ratios of 17.5 at 2 h and 1.7 at 24 h. The CG to Vabicaserin AUC 0-24 ratio of 12:1 indicates that the CG is a major metabolite in monkeys. MCE has not independently confirmed the accuracy of these methods. They are for reference only.Animal administrationMice and Rats For metabolism studies in mice, rats, and dogs, radiolabeled doses are used. Male and female CD-1 mice and Sprague-Dawley rats are used. The dose vehicle for mice and rats contained 2% (w/w) Tween 80 and 0.5% methylcellulose in water. Nonfasted male and female mice weighing from 27.8 to 33.8 g at the time of dosing are given a single 50-mg/kg (∼300 µCi/kg) dose of Vabicaserin at a volume of 20 mL/kg via intragastric gavage. Mice are kept in metabolic cages in groups of five. Nonfasted male rats weighing from 318 to 345 g and female rats weighing from 227 to 255 g at the time of dosing are given a single 5-mg/kg (∼300 µCi/kg) dose of Vabicaserin at a volume of 2.5 mL/kg via intragastric gavage. Four bile duct-cannulated male rats weighing from 387 to 411 g and four bile duct-cannulated female rats weighing from 291 to 325 g at the time of dosing are nonfasted and are given a single 5-mg/kg (323 µCi/kg) dose of Vabicaserin at a volume of 5.0 mL/kg via intragastric gavage. Rats are kept individually in metabolism cages. Dogs Four male beagle dogs, weighing from 7.6 to 9.8 kg at the time of dosing, are from an in-house colony. Approximately 11 mg of [ 14 C]Vabicaserin hydrochloride and 940 mg of nonlabeled Vabicaserin hydrochloride are dissolved in methanol and then evaporated under a nitrogen stream to dryness. Capsules (number 2) are filled with accurate amounts (126.7-138.1 mg) of the mixed drug substance according to animal weights to give a dosage of 15 mg/kg (39 µCi/kg). The filled gelatin capsules are then enteric-coated manually. Each dog is given one enteric-coated capsule containing [ 14 C]Vabicaserin as the hydrochloride salt. Animals are fed 2 h before dosing and are housed individually in metabolic cages. Monkey Four male cynomolgus monkeys, weighing from 5.4 to 9.6 kg at the time of dosing, are from an in-house colony. Nonfasted monkeys are given a single 25-mg/kg dose of nonradiolabeled Vabicaserin at a volume of 2 mL/kg via intragastric gavage. The vehicle is the same as used in mice and rats. Animals are housed individually in metabolic cages. aladdin has not independently confirmed the accuracy of these methods. They are for reference only.IC50& Target:5-HT 2C Receptor 8 nM (EC 50 )... Read More |