| Description | ADAMTSL4 Human Pre-designed siRNA Set A contains three designed siRNAs for ADAMTSL4 gene (Human), as well as a negative control, a positive control, and a FAM-labeled negative control. Components ADAMTSL4 siRNA-1: 5 nmol (HPLC) ADAMTSL4 siRNA-2: 5 nmol (HPLC) ADAMTSL4 siRNA-3: 5 nmol (HPLC) siRNA ADAMTSL4 Human Pre-designed siRNA Set A contains three designed siRNAs for ADAMTSL4 gene (Human), as well as a negative control, a positive control, and a FAM-labeled negative control. Components ADAMTSL4 siRNA-1: 5 nmol (HPLC) ADAMTSL4 siRNA-2: 5 nmol (HPLC) ADAMTSL4 siRNA-3: 5 nmol (HPLC) siRNA Negative Control: 5 nmol (HPLC) FAM-labeled siRNA Negative Control: 5 nmol (HPLC) GAPDH siRNA Positive Control:5 nmol (HPLC)... Read More | C1q separated from C1r and C1s and from other stabilizing proteins tends to aggregate easily. Because it was isolated and studied in numerous research laboratories, many buffers have been used to stabilize concentrated C1q and prevent aggregation. About half of the scientists prefer high salt and C1q separated from C1r and C1s and from other stabilizing proteins tends to aggregate easily. Because it was isolated and studied in numerous research laboratories, many buffers have been used to stabilize concentrated C1q and prevent aggregation. About half of the scientists prefer high salt and the other prefer 40% glycerol in the storage buffer.C1q is purified from pooled normal human plasma. C1q is part of the C1 complex and this complex is the first complement component in the cascade referred to as the classical pathway of complement. C1 is actually a non-covalent assembly of three different proteins (C1q, C1r, and C1s) bound together in a calcium-dependent complex. C1q has six extended arms with domains at the end of each arm that bind to the Fc domains of immunoglobulins. When antibodies bind to antigens forming immune complexes they cluster allowing two or more of its six arms of C1q to bind to the Fc domains of antibodies such as IgG or IgM. The binding of multiple arms to immune complexes causes the two C1r proteins in the complex (protease zymogens) to auto-activate producing two C1r proteases that cleave and activate the two C1s protease zymogens in the complex. Activated C1s cleaves complement component C4 releasing C4a and initiating covalent attachment of C4b to the activating surface. Activated C1s also cleaves C2 and the larger fragment of C2 binds to the surface-attached C4b forming C4b,C2a which is the C3/C5 convertase of the classical pathway.Extinction Coeff.A₂₈₀ nm = 0.68 at 1.0 mg/ml for pure C1q Molecular weight:410,000 Da (18 chains)Preservative:None, 0.22 µm filtered.Source:Normal human serum (shown by certified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II).Physical Characteristics & StructureC1q is a high molecular weight complex of 18 polypeptide chains. Each of the six arms of C1q contains three chains, an A chain (26,000 daltons), a B chain (25,000 daltons) and a C chain (24,000 daltons). The three chains are coiled into a collagen-like triple helix over approximately half their length. Half of this collagen region forms a central core where all 18 chains come together. The chains are joined in this core by disulfides in the pattern A-B and C-C. There is a bend in the center of the collagen region allowing the arms to extend away from each other. Globular heads at the far ends of the collagen arms possess binding sites for Fc domains of immunoglobulins. C1 complex is composed of one C1q molecule (410,000 daltons), two C1r molecules (92,000 daltons) and two C1s molecules (86,000 daltons). The complex is stable in the presence of calcium, but easily dissociates if calcium is removed. When C1 is activated the C1r and C1s subunits are each cleaved into two chain molecules due to proteolytic activation. Thus, the SDS gel pattern of C1 is very complex. Function The biological functions of C1q are described above in the General Description and Physical Characteristics sections. C1q functional activity may be assayed using C1q-depleted serum and EA cells. These assays are extremely sensitive to C1q typically yielding 50% lysis with less than 2 ng C1q in assays measuring the lysis of EA cells. AssaysThe unit of classical pathway activity is the CH50. A similar unit, the C1qH50, is used to quantitate the activity of C1q. A C1qH50 unit is the amount of functional C1q needed to lyse 50% of 3×10^7 EA cells (antibody-sensitized sheep erythrocytes) when that amount of C1q is incubated with 5-20 µL of C1q-Dpl in GVB++ in a total volume of 500 µL for 30 min at 37℃. This amount of C1q indicates the sensitivity of the assay for C1q which is typically about 1 ng C1q with 10 µL C1q-Dpl. See the Certificate of Analysis for lot specific values.ApplicationsC1q is used to coat ELISA plates to capture and quantitate immune complexes in clinical samples. A number of commercial companies sell diagnostic kits for immune complex detection and quantitation. These kits are based on the ability of C1q to bind well to immune complexes, but to not bind significantly to monomeric immunoglobulins. GeneticsThe EMBL/Genbank cDNA accession numbers are: C1q A chain (P02745), C1q B chain (P02746), and C1q C chain (P02747). The genes for C1q chains A, B and C are all located on chromosome 1p in the order A-C-B. DeficienciesDeficiencies of each of the three components of C1 have been found. Patients lacking C1q generally have immune-complex-mediated renal disease and skin lesions. Like all patients lacking early classical pathway components C1q deficient individuals are prone to systemic lupus erythrematosis (SLE) and recurrent pyogenic infections. They lack classical pathway function and may or may not exhibit C1q antigen in blood.DiseasesSee section titled Deficiencies above. Precautions/Toxicity/HazardsThis protein is purified from human serum and therefore precautions appropriate for handling any blood-derived product must be used even though the source was shown by certified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II... Read More | Product DescriptionEndo F2 cleaves N-linked (asparagine-linked) biantennary oligosaccharides from glycoproteins. It also will cleave high mannose glycans but at a 40x reduced rate. It cleaves between the two N-acetylglucosamine residues in the diacetylchitobiose core of the oligosaccharide, Product DescriptionEndo F2 cleaves N-linked (asparagine-linked) biantennary oligosaccharides from glycoproteins. It also will cleave high mannose glycans but at a 40x reduced rate. It cleaves between the two N-acetylglucosamine residues in the diacetylchitobiose core of the oligosaccharide, generating a truncated sugar molecule with one N-acetylglucosamine residue remaining on the asparagine. In contrast, PNGase F removes the oligosaccharide intact.Endoglycosidase F2 is less sensitive to protein conformation than PNGase F and is therefore more suitable for deglycosylation of native proteins. However, for optimal results, denaturation of the glycoprotein is recommended.Contents60 µl aliquot of enzyme (0.3 U) in 10 mM sodium acetate 25mM NaCl, pH 4.5Included with 20 µL and 60 µL pack sizes:5x Reaction Buffer – 250 mM sodium acetate, pH 4.5Molecular weight 32,000 daltonsSpecific Activity Defined as the amount of enzyme required to catalyze the release of N-linked oligosaccharides from 1 micromole of denatured porcine fibrinogen in 1 minute at 37°C, pH 5.5. Cleavage is monitored by SDS-PAGE (cleaved fibrinogen migrates faster).Formulation The enzyme is provided as a sterile-filtered solution in 10 mM sodium acetate, 25mM NaCl, pH 4.5Specificity Endo F2 cleaves Asparagine-linked biantennary and high mannose glycans (at a 40X reduced rate). It cleaves between the two N-acetylglucosamine residues in the diacetylchitobiose core of the oligosaccharide, generating a truncated sugar molecule with one N-acetylglucosamine residue remaining on the asparagine. In contrast, PNGase F removes the oligosaccharide intact. Endoglycosidase F2 is less sensitive to protein conformation than PNGase F and is therefore more suitable for deglycosylation of native proteins. However for optimal results, denaturation of the glycoprotein is recommended.Quality & Purity Endo F2 is tested for contaminating protease as follows: 10 µg of denatured BSA is incubated at 37°C for 24 hours with 2 µl of enzyme. SDS-PAGE analysis of the treated BSA shows no evidence of degradation. The production host strain has been extensively tested and does not produce any detectable glycosidases.Stability Several days exposure to ambient temperatures will not reduce activity. Stable at least 12 months when stored properly.Directions for use 1. Add up to 200 µg of glycoprotein to an Eppendorf tube. Adjust to 38 µl final volume with de-ionized water. 2. Add 10 µl 5x Reaction Buffer 4.5 3. Add 2.0 µl of Endo F2 to the reaction. Incubate 1 hour at 37°C. Monitor cleavage by SDS-PAGEThe production host strain has been extensively tested and does not produce any detectable glycosidases... Read More | Lipase PS is generally used in the enantioselective transesterification and hydrolysis. Applications include: 1.Lipase catalyzed transesterification of prochiral pyrimidine acyclonucleoside. 2.Lipase catalyzed hydrolysis of diacetylated pyrimidine acyclonucleosides. 3. Enantiomer selective acylationLipase PS is generally used in the enantioselective transesterification and hydrolysis. Applications include: 1.Lipase catalyzed transesterification of prochiral pyrimidine acyclonucleoside. 2.Lipase catalyzed hydrolysis of diacetylated pyrimidine acyclonucleosides. 3. Enantiomer selective acylation of racemic alcohols in continuous-flow bioreactors... Read More | Tyrosine decarboxylase catalyzes the removal of the carboxyl group from tyrosine to produce tyramine and carbon dioxide. Pyridoxal 5'-phosphate is a necessary cofactor. By using the apoenzyme prepared from cells grown on a vitamin B6 deficient medium pyridoxal phosphate may be determined. The Tyrosine decarboxylase catalyzes the removal of the carboxyl group from tyrosine to produce tyramine and carbon dioxide. Pyridoxal 5'-phosphate is a necessary cofactor. By using the apoenzyme prepared from cells grown on a vitamin B6 deficient medium pyridoxal phosphate may be determined. The HOLOenzyme may be used to determine tyrosine, phenylalanine and dihydroxyphenylalanine either manometrically or colorimetrically.L-Tyrosine decarboxylase apoenzyme from Streptococcus faecalis has been used in a study to purify and characterize tyrosine decarboxylase and aromatic-L-amino-acid decarboxylase.L-Tyrosine decarboxylase apoenzyme from Streptococcus faecalis has also been used in a study to investigate the stereospecificity of sodium borohydride reduction of tyrosine decarboxylase.One Unit yields 1µmole of CO2 per minute from L-tyrosine at 37°C, pH 5.5. The APOenzyme activity is measured in the presence of excess pyridoxal phosphate... Read More |