Category: Serine/Threonine

  • Chondroitin sulfate

    CHONDROITIN SULFATE is a sulfated glycosaminoglycan (GAG) composed of a chain of alternating sugars (N-acetylgalactosamine and glucuronic acid). It is usually found attached to proteins as part of a proteoglycan. A chondroitin chain can have over 100 individual sugars, each of which can be sulfated in variable positions and quantities. Chondroitin sulfate is an important structural component of cartilage, and provides much of its…

    Read more...

  • Steroidogenic factor 1 (SF-1) protein and a few related things

    The steroidogenic factor 1 (SF-1) protein is a transcription factor involved in sex determination by controlling the activity of genes related to the reproductive glands or gonads and adrenal glands. This protein is encoded by the NR5A1 gene, a member of the nuclear receptor subfamily, located on the long arm of chromosome 9 at position 33.3. It was originally identified as a regulator of genes encoding cytochrome P450 steroid hydroxylases, however, further roles…

    Read more...

  • Subtilisin

    Subtilisin is a protease (a protein-digesting enzyme) initially obtained from Bacillus subtilis. Subtilisins belong to subtilases, a group of serine proteases that – like all serine proteases – initiate the nucleophilic attack on the peptide (amide) bond through a serine residue at the active site. Subtilisins typically have molecular weights 27kDa. They can be obtained from certain types of soil bacteria, for example, Bacillus amyloliquefaciens from which they are secreted in large amounts. Nomenclature “Subtilisin”…

    Read more...

  • Proprotein convertases (PPCs) are a family of proteins that activate other proteins

    Many proteins are inactive when they are first synthesized, because they contain chains of amino acids that block their activity. Proprotein convertases remove those chains and activate the protein. The prototypical proprotein convertase is FURIN. Proprotein convertases have medical significance, because they are involved in many important biological processes, such as cholesterol synthesis. Compounds called proprotein convertase inhibitors…

    Read more...

  • Structure of DNA repair protein XRCC4  aka X-ray repair cross-complementing protein 4

    XRCC4 protein is a TETRAMER that resembles the shape of a DUMBBELL containing two globular ends separated by a long, thin stalk. The tetramer is composed of two dimers, and each dimer is made up of two similar subunits. The first subunit (L) contains amino acid residues 1 – 203 and has a longer stalk than the second…

    Read more...

  • Staphylokinase (SAK) aka staphylococcal fibrinolysin or Müller’s factor

    Staphylokinase (SAK; also known as staphylococcal fibrinolysin or Müller’s factor) is a protein produced by Staphylococcus aureus. It contains 136 amino acid residues and has a molecular mass of 15kDa. Synthesis of staphylokinase occurs in late exponential phase. It is similar to streptokinase. Fibrinolysin is an enzyme derived from plasma of bovine origin (plasmin) or extracted from cultures of certain bacteria. (more below) Staphylokinase is positively…

    Read more...

  • DREAM complex

    The dimerization partner, RB-like, E2F and multi-vulval class B (DREAM) complex is a protein complex responsible for the regulation of cell cycle-dependent gene expression. The complex is evolutionarily conserved, although some of its components vary from species to species. In humans, the key proteins in the complex are RBL1 (p107) and RBL2 (p130), both of which are homologs of RB (p105) and bind repressive E2F…

    Read more...

  • Cathepsin G

    Cathepsin G plays an important role in eliminating intracellular pathogens and breaking down tissues at inflammatory sites, as well as in anti-inflammatory response

    Read more...

  • Thrombin

    Thrombin (fibrinogenase, thrombase, thrombofort, topical, thrombin-C, tropostasin, activated blood-coagulation factor II, blood-coagulation factor IIa, factor IIa, E thrombin, beta-thrombin, gamma-thrombin) is a serine protease, an enzyme that, in humans, is encoded by the F2 gene. During the clotting process, prothrombin (coagulation factor II) is proteolytically cleaved by the prothrombinase enzyme complex to form thrombin. Thrombin in turn acts as a serine protease that converts soluble fibrinogen into insoluble strands of fibrin, as well as catalyzing many other coagulation-related reactions. History After the description…

    Read more...

  • Elastase

    In molecular biology, elastase is an enzyme from the class of proteases (peptidases) that break down proteins. In particular, it is a serine protease. Forms and classification Eight human genes exist for elastase: Family Gene symbol Protein name EC number Approved Previous Approved Previous chymotrypsin-like CELA1 ELA1 chymotrypsin-like elastase family, member 1 elastase 1, pancreatic EC 3.4.21.36 CELA2A ELA2A chymotrypsin-like elastase family, member 2A elastase 2A, pancreatic EC 3.4.21.71 CELA2B…

    Read more...

  • β-Glucuronidases

    For α-glucuronidase, see alpha-glucuronidase. β-Glucuronidase β-Glucuronidase asymmetric unit showing active site residues Glu451, Tyr504, and Glu540, along with the potentially supporting Asn450 residue Identifiers Symbol GUSB NCBI gene 2990 HGNC 4696 OMIM 611499 RefSeq NM_000181 UniProt P08236 Other data EC number 3.2.1.31 Locus Chr. 7 q11.21 β-Glucuronidases are members of the glycosidase family of enzymes that catalyze breakdown of complex carbohydrates. Human β-glucuronidase is…

    Read more...

  • Testican

    Testican is a type of proteoglycan. Testican-1 is a highly conserved, multidomain proteoglycan that is most prominently expressed in the thalamus, and is upregulated in activated astroglial cells of the cerebrum. Several functions of this gene product have now been demonstrated in vitro including membrane-type matrix metalloproteinase inhibition, cathepsin L inhibition, and low-affinity calcium binding. The purified gene product has been shown to inhibit cell attachment…

    Read more...

  • Keratan sulfate (KS) aka keratosulfate

    Not to be confused with Keratin. Keratan sulfate (KS), also called keratosulfate, is any of several sulfated glycosaminoglycans (structural carbohydrates) that have been found especially in the cornea, cartilage, and bone. It is also synthesized in the central nervous system where it participates both in development and in the glial scar formation following an injury. Keratan sulfates are large, highly hydrated molecules which in joints can act as a cushion to…

    Read more...

  • Agrin is a large chimeric proteoglycan, a heparan sulfate and chondroitin proteoglycan, whose best-characterised role is in the development of the neuromuscular junction during embryogenesis

    Agrin was originally found in the electric organ of Tarpedo california and in the basal lamina at the neuromuscular junction as a protein that directs the aggregation of acetylcholine receptors (AChR) and acetylcholinesterase (AChE) at synaptic sites. Tetronarce californica also known as the Pacific electric ray is a species of electric ray in the family Torpedinidae, endemic to the coastal waters of the northeastern Pacific Ocean from Baja California to British Columbia. It generally inhabits sandy flats, rocky reefs, and kelp forests from the surface…

    Read more...

  • Phosphorylation

    In biochemistry, phosphorylation is the attachment of a phosphate group to a molecule or an ion.[1] This process and its inverse, dephosphorylation, are common in biology.[2] Protein phosphorylation often activates (or deactivates) many enzymes.[3][4] During respiration and photosynthesis Phosphorylation is essential to the processes of both anaerobic and aerobic respiration, which involve the production of adenosine triphosphate (ATP), the “high-energy” exchange medium in the cell. During aerobic respiration, ATP is synthesized…

    Read more...

  • Human cells contain a DNA-activated protein kinase that phosphorylates simian virus 40 T antigen, mouse p53, and the human Ku autoantigen

    Abstract HeLa cells contain a serine/threonine protein kinase (DNA-PK) that is strongly activated in vitro by low concentrations of double-stranded DNA (dsDNA). Activation was specific for dsDNA; both natural DNAs and synthetic oligonucleotides functioned as kinase activators. The fact that DNA-PK activity was rapidly inhibited by incubation with dsDNA and ATP suggests that DNA-PK activity…

    Read more...

Scroll back to top