tetrahydro-L-Biopterin (BH4) is a cofactor that, in the presence of enzyme site iron, binds to phenylalanine hydroxylase, tryptophan or tyrosine hydroxylase, and nitric oxide synthase (NOS), to facilitate the production of aromatic amino acids, neurotransmitters, and nitric oxide (NO), respectively.{59239,1697,45725} It is formed de novo from GTP with GTP cyclohydrolase-1 (GCH1) catalyzing the rate limiting conversion of GTP to 7,8-dihydroneopterin (NH2TP) followed by subsequent processing by TS and SPR to convert NH2TP to BH4.{59240,45725} BH4 acts as a radical-trapping antioxidant that inhibits phospholipid oxidation in lipid membranes.{59240} It inhibits IKE- or RSL3-induced ferroptosis in HT-1080 cells (EC50s = 21 and 69 µM), as well as ferroptosis induced by knockout of glutathione peroxidase (Gpx4-/-) in immortalized mouse fibroblasts.{45725} BH4 also reduces RLS3-induced lipid peroxidation in murine fibroblasts and HT-1080 cells when used at a concentration of 50 µM.
Available on backorder
A cofactor for production of aromatic amino acids, neurotransmitters, and nitric oxide
Formal name: 2-amino-6R-(1R,2S-dihydroxypropyl)-5,6,7,8-tetrahydro-4(1H)-pteridinone, dihydrochloride
Synonyms: BH4
Molecular weight: 314.2
CAS: 69056-38-8
Purity: ≥99%
Formulation: A crystalline solid
Cyclin-dependent kinases (CDKs) are key regulators of cell cycle progression and are therefore promising targets for cancer therapy. (R)-Roscovitine is a potent inhibitor of Cdk2/cyclin E with an IC50 value of 0.1 µM.{14988} It also inhibits Cdk7/cyclin H, Cdk5/p35, and cell division cycle (cdc)/cyclin B with IC50 values of 0.49, 0.16, and 0.65 µM, respectively.{14987,14988,14991} (R)-Roscovitine inhibits the growth of rapidly proliferating cells with an average IC50 value of 15.2 µM against a panel of 19 human tumor cell lines.{14988} In murine models of polycystic kidney disease, (R)-roscovitine effectively inhibited disease progression at doses of 50-100 mg/kg.{14564}
Available on backorder
1,2-Dipalmitoyl-sn-glycero-3-PC (DPPC) is a zwitterionic glycerophospholipid commonly used in the formation of lipid monolayers, bilayers, and liposomes for use in a variety of applications.{14480,24261,14478,14479} It has been used in the formation of proteoliposomes for implantation of γ-glutamyl transpeptidase into human erythrocyte membranes.{14478} Incorporation of glycosphingolipid antigens into DPPC-containing liposomes increases the immunogenicity of the antigens in mice.{14479}
Available on backorder
The tetracycline repressor (TetR) is a transcriptional regulator which normally binds tightly to its palindromic tetO operator DNA, blocking gene expression.{17508} Tet causes the repressor to dissociate from the DNA, allowing transcription to occur. A novel reverse TetR (revTetR) requires tetracycline as a co-repressor to bind tetO and block transcription.{17509,17510} Anhydrotetracycline (hydrochloride) is a powerful effector in both the tetracycline repressor (TetR) and reverse TetR (revTetR) systems, binding the Tet repressor 35-fold more strongly than Tet.{17508,17511} Moreover, anhydrotetracycline poorly binds the 30S ribosomal subunit, compared to Tet,{17512} so it does not act as a general inhibitor of translation and is a poor antibiotic. Perhaps related to this, the concentration of anhydrotetracycline that inhibits eukaryotic cell growth is more than a 1,000-fold above the dose that alters transcription through TetR.{17508}
Available on backorder
The PtdIn phosphates play an important role in the generation and transduction of intracellular signals.{8344,4096,14518} PtdIns-(3,4,5)-P3-biotin is an affinity probe which allows the PIP3 to be detected through an interaction with the biotin ligand. This design allows PtdIns-(3,4,5)-P3-biotin to serve as a general probe for any protein with a high affinity binding interaction with inositol-(3,4,5)-triphosphate phospholipids, such as phosphatidylinositol 3-kinase, PTEN, or PH-domain-containing proteins.
Available on backorder