| Description | Format:2-ComponentEnzyme:Horseradish peroxidase | Amyloid β-Protein Fragment 25-35 (Aβ25-35) is derived from the amyloid-β protein.amyloid-β protein, which is mapped to human chromosome 21q21.Aβ25-35 lacks the N-terminal domain and the metal binding site and is majorly generated by proteolytic cleavage of Aβ(1−40Amyloid β-Protein Fragment 25-35 (Aβ25-35) is derived from the amyloid-β protein.amyloid-β protein, which is mapped to human chromosome 21q21.Aβ25-35 lacks the N-terminal domain and the metal binding site and is majorly generated by proteolytic cleavage of Aβ(1−40) peptides. It has a β-sheet and β-turn structure. Amino Acid Sequence Gly-Ser-Asn-Lys-Gly-Ala-Ile-Ile-Gly-Leu-MetFunctional domain of Aβ required for both neurotrophic and neurotoxic effects... Read More | Purity>90% by SDS-PAGEExtinction Coeff.A280 nm = 0.988 at 1.0 mg/mLPrecautionsUse normal precautions for handling human blood productsGeneral DescriptionNative human C9 is a naturally glycosylated (7.8%) protein composed of a singlepolypeptide chain. The molecular weight is 71,000 Da. C9 binds toPurity>90% by SDS-PAGEExtinction Coeff.A280 nm = 0.988 at 1.0 mg/mLPrecautionsUse normal precautions for handling human blood productsGeneral DescriptionNative human C9 is a naturally glycosylated (7.8%) protein composed of a singlepolypeptide chain. The molecular weight is 71,000 Da. C9 binds to the C5b-8 complex and forms the mature membrane attack complex (MAC) on cell membranes. Each pathway of complement activation generates proteolytic enzyme complexes (C3/C5 convertases) which are bound to the target surface (Ross, G.D. (1986)). These enzymes cleave a peptide bond in the larger alpha chain of C5 releasing the anaphylatoxin C5a and activating C5b. This is the only proteolytic step in the assembly of the C5b-9 complex. C5b is unstable, but it remains bound to the activating complex for a brief time (~2 min) during which it either binds a single C6 from the surrounding fluid or decays and is no longer capable of forming MAC. The C5b,6 complex may also remain bound to the C3/C5 convertase where the binding of a single C7 exposes a membrane-binding region and C5b,6,7 can partially insert into the bilipid layer of the target cell. Up to this point the complex may diffuse away from the target cell and enter the membrane of a nearby cell. This is called bystander lysis or “reactive lysis” and can be a significant source of pathology. Each C5b-7 complex can bind one C8 protein molecule which results in the complex inserting more firmly into the membrane. The C5b-8 complex is capable of causing lysis without C9 although this is slow and requires many more complexes per cell than with C9. This property complicates C9 titrations since the precursor (C5b-8) can also cause lysis. The primary role of C8 is to catalyze the binding of C9 and each bound C9 can bind another C9 initiating formation of a ring structure containing up to 18 molecules of C9 (Podack, E.R. (1984)). C5b-9 complexes with one or more C9 are referred to as the Membrane Attack Complex (MAC) of complement. Not all C5b-8 complexes have complete rings of C9 with the average being only three C9 per C5b-8complex. Nevertheless, these structures are capable of causing lysis if enough are formed in a given cell. Completed protein rings of C9 form the pores seen on electron micrographs and they result in leakage of metabolites and small proteins out of the cell as well as movement of water into the cell. If sufficient numbers are inserted into a cell membrane then water flowing into the cell, due to osmotic pressure, will rupture the cell membrane allowing the entire contents of the target cell (or a bystander cell) to be released. Either process may result in cell death. Originally it was thought that this required only one C5b-9 complex per cell (referred to as the “one hit theory” of lysis (Rommel F.A. and Mayer, M.M. (1973)), but this is probably not correct. For example, an erythrocyte without CD59 requires ~850 C5b-9 complexes, as measured by the number of C7 molecules, for lysis to occur (Bauer, J. et al. (1979)). Host cells protected from MAC by CD59 require sufficient numbers of C5b-9 to tie up all the CD59 and then ~850 C5b-9 in addition. Lysis of nucleated cells requires many more C5b-9 complexes due to their size and due to the presence of multiple defense mechanisms in such cells.Physical Characteristics & StructureThe molecular weight of C9 is 71,000 Da and it is a single polypeptide chain. The protein contains 7.8% carbohydrate attached at two N-linked glycosylation sites. The pI of C9 is 4.7. C9 may polymerize spontaneously forming MAC rings without C5b-8. The rings formed from pure C9 as well as the completed rings formed by C5b-9 with 12 to 18 C9 molecules have the unusual property of being stable in boiling SDS even though they are non-covalently bound. Function See General Description above. Assays Assays for C9 function are complicated by the fact that if excess C5-C8 is used cells (EA or Er) will be lysed by the C5b-8 complex. Thus it is critical to use limited C8 in these assays to keep the background lysis to a minimum. The simplest assay for C9 is to use C9-depleted human serum and measure the lysis of EA (classical pathway) or Er (alternative pathway) as a function of the concentration of added test sample or standard purified C9. Each unique application might require appropriate conditions to be determined. However, a typical assay would involve mixing on wet ice ~5 µL C9-Dpl, C9-containing sample diluted with GVB⁺⁺ to contain from 1 to 10 ng C9, and sufficient GVB⁺⁺ to bring the volume to 300 µL. EA (3 X 10⁷ cells in 200 µL) diluted in GVB⁺⁺ should be added last. Purified C9 or normal human serum (NHS) may be used as a source of C9. The reaction mixture is incubated for 30 min at 37℃ and 1 mL of cold GVBE added, mixed and centrifuged to spin down unlysed cells. The released hemoglobin in the supernatant is then analyzed at 415 nm and compared to blanks without C9 (background lysis control) and cells incubated with 275 µL water instead of GVB⁺⁺ and 25 µL C9-Dpl (100% lysis control). Note as mentioned above, at inputs of serum higher than ~5 µL of C9-Dpl, EA and other target cells may also be lysed in the absence of C9 depending on the cells’ susceptibility to C5b-9.Many other assays have been described using EA preloaded with C1 (EAC1 cells) or preloaded with the classical pathway C5 convertase (EAC1423 cells), however, all these assays require the use of multiple purified complement components or more difficult-to-prepare reagents (Dodds, A.W. and Sim, R.B. (1997; Morgan, B.P. (2000);Tack, B.F., et al. (1981)).ApplicationsSee General Description aboveIn vivoThe normal serum concentration of C9 is 60 µg/mL (normal range 47 to 70µg/mL). The primary site of synthesis is the liver. C9 is also produced by monocytes, macrophages, fibroblasts and glial cells. C9 is an acute phase protein and its synthesis is stimulated by cytokines (such as IFNγ) that stimulate increased biosynthesis of many other complement proteins.RegulationMany proteins and other components of plasma have an inhibitory effect on the lytic activity of C5b-9 complexes but there are no specific C9 inactivators. Most of the C5b-9 inhibitors interact with the complex after the C5b-7 stage. If any of the C5bcontaining complexes fail to insert into a membrane they may self-aggregate or bind to regulatory proteins the most prevalent of which is S Protein. S Protein (also called vitronectin) is an 80,000 Da plasma protein found bound to most soluble C5b-9 complexes. Many other serum components inhibit or partially inhibit lysis by C5b-9 and these include SP40,40 (also known as clusterin and apolipoprotein J) and many plasma lipoprotein complexes (LDL, HDL, etc.).Host cells protect themselves from C5b-9 by a variety of mechanisms. Membrane proteins DAF, MCP, and CR1 inhibit formation of C3/C5 convertases preventing MAC formation. CD59, also called “homologous restriction factor” and “protectin”, is a 18,000 to 20,000 Da ubiquitous component of cell membranes that is very effective at binding to and inhibiting the lytic potential of C5b-8 and C5b-9 complexes. The speciesspecificity of CD59 is not absolute and many mammalian CD59 proteins inhibit or partially inhibit MAC from other species. The specificity that is observed appears to be due to incompatibilities between C8 of one animal and the CD59 of another. Like DAF, CD59 contains a GPI anchor (a post-translationally added lipid tail that inserts into the bilipid layer of the cell). The disease PNH is caused by the loss of enzymes that attach the GPI tail, thus depriving cells of the ability to express DAF and inactivate C3/C5 convertases and the ability express CD59 to inactivate C5b-9. This results in the spontaneous lysis by complement of the most susceptible cells such as erythrocytes and platelets.GeneticsHuman chromosome location 5p 13. Accession number HSC6A. Mouse chromosome 15. Human genomic structure: the gene spans 100 kb with 11 exons.DeficienciesHuman C9 deficiencies are quite common. A well documented study found that 1:1000 people in the Janaese population were C9 deficient although other ethnic groups have lower incidents of C9 deficiency (Horiuchi, T. et al. (1998)). Deficiencies exhibit autosomal recessive transmission. Patients generally exhibit abnormally high susceptibility to recurrent meningococcal meningitis and systemic neisserial infections. Partial deficiencies do not seem to show adverse clinical effects.DiseasesSee Deficiencies above.Precautions/Toxicity/HazardsThis protein is purified from human plasma, therefore precautions appropriate for handling any blood-derived product must be used even though the source was shown bycertified tests to be negative for HBsAg, HTLV-I/II, STS, and for antibodies to HCV, HIV-1 and HIV-II.Hazard Code: B WGK Germany 3MSDS available upon request... Read More | GoldStar Probe Mixture is a premixed system specifically designed for real-time fluorescence quantitative PCR using probe methods (TaqMan, Molecular Beacon, etc.), with a concentration of 2 x, containing GoldStar Taq DNA Polymerase, PCR Buffer, dNTPs, and Mg2+. The operation is simple and convenientGoldStar Probe Mixture is a premixed system specifically designed for real-time fluorescence quantitative PCR using probe methods (TaqMan, Molecular Beacon, etc.), with a concentration of 2 x, containing GoldStar Taq DNA Polymerase, PCR Buffer, dNTPs, and Mg2+. The operation is simple and convenient. Mainly used for detecting genomic DNA target sequences and RNA reverse transcription cDNA target sequences, such as gene expression analysis, copy number analysis, SNP genotype analysis, etc., suitable for fluorescence quantification using different types of probe methods. The GoldStar Taq DNA Polymerase contained in this product is a chemically modified, novel and highly efficient hot start enzyme. It has no polymerase activity at room temperature, effectively avoiding non-specific amplification caused by non-specific binding of primers and templates or primer dimerization at room temperature. The enzyme activation requires incubation at 95 ℃ for 10 minutes. The unique combination of PCR buffer system and hot start enzyme significantly improves the amplification efficiency of PCR, with stronger fluorescence signal and higher sensitivity, which can detect single copy templates. By using this product, a wider linear range can be obtained, resulting in more accurate quantification of the target gene. Suitable for all fluorescence quantitative PCR instruments that do not require ROX as a calibration dye.ROX dye is used to correct the fluorescence signal error between wells in quantitative PCR instruments, and is generally used in Real Time PCR amplification instruments from companies such as ABI and Stratagene. The excitation optical systems of different instruments vary, so the concentration of ROX dye must be matched with the corresponding fluorescence quantitative PCR instrument.Instruments that do not require ROX calibration (CW0932): Roche LightCycle 480, Roche LightCyler 96, Bio rad iCyler iQ, iQ5, CFX96, etc.Instrument requiring Low ROX calibration (CW2625): ABI Prism7500/7500 Fast, QuantStudio ® 3 System, QuantStudio ® 5 System, QuantStudio ® 6 Flex System, QuantStudio ® 7 Flex System, ViiA 7 System, Stratagene Mx3000/Mx3005P, Corbett Rotor Gene 3000, etc.Instruments that require High ROX calibration (CW2626): ABI Prism7000/7300/7700/7900, Eppendorf, ABI Step One/Step One Plus, etc.G665832Component5 mLStorageG665832A2×GoldStar Probe Mixture5×1 mL-20℃. Avoid freeze/thaw cycle.G665832BddH2O5×1 mL -20℃. Avoid freeze/thaw cycle. Notes:1. Before use, please gently mix upside down to avoid foaming, and use after briefly centrifugation.2. Avoid repeated freezing and thawing of this product, as repeated freezing and thawing may cause a decrease in product performance. This product can be stored for a long time at -20 ℃, away from light. If frequent use is required in the short term, it can be stored at 2-8 ℃.Usage:The following are examples of conventional PCR reaction systems and reaction conditions. In practical operation, corresponding improvements and optimizations should be made based on different templates, primer structures, and target fragment sizes.1. PCR reaction system Reagent 50 µl Reaction system Final concentration 2×GoldStar Probe Mixture 25 µl 1 × Forward Primer，10 µM 1 µl 0.2 µM¹⁾ Reverse Primer，10 µM 1 µl 0.2 µM¹⁾ Probe，10 µM 1 µl 0.2 µM²⁾ Template DNA 2 µl³⁾ / 50×Low ROX or High ROX（optional）⁴⁾ 1 µl 1 × ddH2O up to 50 µl / Attention:1) Typically, the primer concentration is 0.2 µ M can achieve good results, ranging from 0.1 to 1.0 µ M serves as a reference for setting the range.2) The concentration of the probe used is related to the fluorescent quantitative PCR instrument used, the type of probe, and the type of fluorescent labeling substance. Please refer to the instrument manual or the specific usage requirements of each fluorescent probe for concentration adjustment during actual use.3) The amount of DNA template is usually based on 10-100 ng genomic DNA or 1-10 ng cDNA as a reference. Due to the different copy numbers of target genes contained in templates of different species, gradient dilution can be applied to the template to determine the optimal template usage.4) The excitation optical systems of different instruments vary, and depending on the instrument used for fluorescence quantification, 50 x Low ROX or 50 x High ROX can be added.2. PCR reaction programAttention! The pre denaturation reaction of this product must be completed at 95 ℃ for 10 minutes!Two step PCR Step Temperature Time / Pre denaturation 95℃ 10 min¹⁾ / Denaturation 95℃ 15 s 35-40 cycles Annealing/Extension ²⁾ 60℃ 1 min 35-40 cycles Attention:1) The hot start enzyme used in this product must be activated under pre denaturation conditions of 95 ℃ and 10 minutes.2) It is recommended to use a two-step PCR reaction program. If good experimental results cannot be obtained due to the use of primers with lower Tm values, a three-step PCR amplification can be attempted. The annealing temperature should be set within the range of 56 ℃ -64 ℃ as a reference... Read More | Inquire |