| Description | β- - AMYLASE A304857 A304857 is a preparation of purified β-amylase obtained from soybean. β- amylase hydrolyzes α-1, 4 glycosidic linkage in starch and glycogen with an inversion of configuration about C(1) position of glucose from α to β. A304857 is more stable than β- - AMYLASE A304857 A304857 is a preparation of purified β-amylase obtained from soybean. β- amylase hydrolyzes α-1, 4 glycosidic linkage in starch and glycogen with an inversion of configuration about C(1) position of glucose from α to β. A304857 is more stable than the corresponding enzymes from wheat and barley malt, and is suitable to produce high maltose syrup from starch. The product consists of 40% β -amylase and 60% Corn starch.Enzyme Unit DefinitionAdd to mix 1ml of enzyme solution with 5ml of 1.2% starch solution (pH 5.5, M / 20 acetate buffer) and keep it for 20 min. at 40 ℃. Under this conditions, 1 AUN is defined as the activity which liberates 100µg of reducing sugar (expressed by dextrose equivalent ) per minute... Read More | Inquire | N-Acetylneuraminyl-fucosyllacto-N-neo-tetraose is used as a reference material in the analysis of milk oligosaccharides | Purity: >95%, by SDS-PAGE visualized with Coomassie® Blue Staining. Description： CD4, also known as L3T4, T4, and W3/25, is an approximately 55 kDa type I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T lymphocytes. It is a standard Purity: >95%, by SDS-PAGE visualized with Coomassie® Blue Staining. Description： CD4, also known as L3T4, T4, and W3/25, is an approximately 55 kDa type I transmembrane glycoprotein that is expressed predominantly on thymocytes and a subset of mature T lymphocytes. It is a standard phenotype marker for the identification of T cell populations. Mature human CD4 consists of a 371 amino acid (aa) extracellular region containing four immunoglobulin-like domains, a 22 aa transmembrane segment, and a 40 aa cytoplasmic domain. Within the ECD, human CD4 shares approximately 52% aa sequence identity with mouse and rat CD4. CD4 is expressed along with CD8 on double positive T cells during their development in the thymus. Either CD4 or CD8 expression is then lost, giving rise to single positive (SP) CD4+ or CD8+ mature T cells. CD4+ SP cells, also known as T helper cells, further differentiate into multiple subsets of CD4+ cells including Th1, Th2, Th17, Tfh, and Treg cells which regulate humoral and cellular immunity. CD4 is reexpressed on circulating CD8+ T cells upon activation and contributes to their cytotoxic effector activity. In human, CD4 is additionally expressed on macrophages, neutrophils, monocytes, NK cells, and neurons and glial cells in the brain. Similar CD4 distribution between species cannot be assumed as demonstrated by its presence on macrophages in human and rat but not in mouse. CD4 binds directly to MHC class II molecules on antigen presenting cells. This interaction contributes to the formation of the immunological synapse which is focused around the TCR-MHC class II-antigenic peptide interaction. Palmitoylation of two cysteine residues in the cytoplasmic tail of CD4 promotes the localization of CD4 in lipid rafts and its ability to augment TCR signaling via activation of the tyrosine kinase Lck. CD4 also functions as a chemotactic receptor for IL-16 and, in human, as a co-receptor for the gp120 surface glycoprotein of HIV-1... Read More | Protein:BovineEnzyme:Horseradish peroxidase |