| Description | Human IgG2-kappa, Recombinant (IB2), Isotype Control, could be used for Flow Cytometry | Inquire | Malic Dehydrogenase is a ubiquitous enzyme, which exists in two isoforms in eukaryotic cells.Malic dehydrogenase exists as a dimer with each subunit containing an NAD-binding domain and a substrate-binding carboxy-terminal domain required for activity. Malic dehydrogenase is a cytoplasmic isozyme Malic Dehydrogenase is a ubiquitous enzyme, which exists in two isoforms in eukaryotic cells.Malic dehydrogenase exists as a dimer with each subunit containing an NAD-binding domain and a substrate-binding carboxy-terminal domain required for activity. Malic dehydrogenase is a cytoplasmic isozyme and an important catalyst in the tricarboxylic acid cycle.ReagentsA. 0.1 M Tris-HCl buffer (pH7.8)B. 0.01 M Phosphate buffer (KH2PO4-NaOH, pH 7.0)C. Triton X-100 solution (50 mg/ml)D. 0.01 M Phosphate buffer containing 0.1% Triton X-100 (KH2PO4-NaOH, pH 7.0)Dilute 20 ml of Triton X-100 solution (C) with approx. 800 ml of 0.01M Phosphate buffer (B). Fill up to 1,000 ml with 0.01M Phosphate buffer (B).E. NADH soluton Weigh 9 mg of NADH and dissolve in 0.1M Tris-HCl bufer (A). Fill up to 50 ml with 0.1M Tris-HCl Buffer (A). (Can be used for 5 days if kept refrigerated)F. Substrate solutionWeigh 11 mg of oxaloacetic acid and dissolve in 0.1M Tris-HCl buffer (A). Fill up to 50 ml with 0.1M Tris-HCl buffer (A) (Make a fresh solution for each use.)G. Enzyme solutionWeigh out Malate Dehydrogenase and dissolve in chilled 0.01M Phosphate Bufer containing 0.1% Triton X-100 (D). Enzyme solution should be prepared so that the value of AOD/minute becomes in the range of 0.025 ± 0.010.ProcedurePipette 2.0 ml of NADH solution (E) and 0.90 ml of Substrate solution (F) respectively into a quartz cell (d=10 mm) and keep at 25 + 0.5'℃ for 5 minutes. Then, pipete 0.10 ml of Enzyme solution (G) into the quartz cell and mix well immediately. Keep the reaction mixture at 25 ±0.5'C.Exaclly at 2 minutes and 5 minutes after the addition of Enzyme solution (G), measure the absorbances of the reaction mixture at 340 nm(A2 and A5).As a blank, pipette 0.01M Phosphate buffer (D) into another quartz cel (d=10 mm) instead of the Enzyme solution (G) and follow the same procedure described above (Ab2 and Ab5).CalculationMalate dehydrogenase activity (u/mg)=[(A2-A5)-(Ab2-Ab5)]/3*(1/6.22)*(n/0.1) ApplicationThis enzyme is used for the enzymatic determination of L-malate and gluamate oxalo-acetate transaminase(GOT)in clinical diagnosis... Read More | Inquire | Purity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining. Description： 100B, previously called S100 beta, belongs to the S100 family within the EF-hand superfamily of Ca2+ binding proteins. S100 proteins contain two EF-hand motifs that differ in affinity, separated by a hingePurity:>95%, by SDS-PAGE visualized with Coomassie® Blue Staining. Description： 100B, previously called S100 beta, belongs to the S100 family within the EF-hand superfamily of Ca2+ binding proteins. S100 proteins contain two EF-hand motifs that differ in affinity, separated by a hinge region with a hydrophobic cleft that is exposed upon Ca2+ binding. S100B is a 91 amino acid (aa) protein, after removal of the initial methionine, and is found as homodimers of 10.4 kDa monomers. Human S100B shares 99%, 98%, 100%, 99% and 97% aa sequence identity with mouse, rat, rabbit, equine and bovine S100B, respectively. Within the S100 family, human S100B shows the highest aa identity (59%) with S100A1. S100B is expressed primarily by astrocytes and oligodendrocytes in the central nervous system, and by Schwann cells in the peripheral nervous system. Ca2+-bound S100B interacts in vitro with at least 20 cytoplasmic proteins, including several structural molecules such as tubulin and GFAP. It can inhibit the phosphorylation of these kinase substrates and others such as tau and neuromodulin. Astrocytes can secrete S100B, which then acts in a cytokine-like manner. Nanomolar concentrations of S100B are secreted constitutively, promote proliferation, and are neurotrophic and anti-apoptotic. Blood levels of S100B reflect extracellular concentrations within the nervous system, and are elevated in Down’s syndrome, Alzheimer’s disease and Tourette’s syndrome, metabolic stress, acute brain injury and brain tumors. Micromolar concentrations of S100B can be destructive and pro-apoptotic; they induce the expression of iNOS, COX-2, IL-1, IL‑6 and TNF-alpha by microglia, astrocytes or neurons. Most extracellular actions of S100B can be mediated by RAGE (receptor for advanced glycation end products), which is also a receptor for other S100 proteins... Read More |