Calcium oxide

Nowadays, biodiesel attracts much attention since it is renewable, sustainable, and can replace fossil fuels. CaO was a suitable heterogeneous catalyst for transesterification reaction to produce biodiesel. In this study, blue crab shell was recycled as the CaO source.

14p viaburame 14-03-2025 2 0   Download

A Convenient and green synthesis of 4H-pyran derivatives via one-pot multicomponent reaction of aromatic aldehydes, malononitrile and ethyl acetoacetate using KOH loaded CaO as a catalyst under solvent free condition is reported. The morphology of the catalyst has been characterized by XRD and TEM.

12p tocectocec 25-05-2020 21 1   Download

In this study, we isolated a 25-kDa novel snake venom protein, designated ablomin, from the venom of the Japanese Mamushi snake (Agkistrodon blomhoffi). The amino-acid sequence of this protein was determined by peptide sequencing and cDNA cloning. The deduced sequence showed high similarity to helothermine from the Mexican beaded lizard (Heloderma horridum horridum), which blocks voltage-gated calcium and potassium channels, and ryanodine receptors. Ablomin blocked contraction of rat tail arterial smooth muscle elicited by high K+-induced depolarization in the 0.

8p system191 01-06-2013 29 3   Download

Department of Molecular and Cellular Neurobiology, Nencki Institute of Experimental Biology, Warsaw, Poland; Department of Biochemistry and Molecular Biology, University of Debrecen, Hungary; 3Department of Inorganic Chemistry, and 4Research Group for Antibiotics, Department of Chemistry, University of Debrecen, Hungary; 5 International Institute of Molecular and Cell Biology, Warsaw, Poland This study characterizes the calcium-bound CR I – II domain (residues 1–100) of rat calretinin (CR).

9p system191 01-06-2013 42 4   Download

In seminiferous tubules, Sertoli cells provide structural and nutritional support for the developing germinal cells. Cellto-cell signaling and cell adhesion require proteoglycans expressed at the cell membrane. A preliminary biochemical and structural approach indicated that cell surface proteoglycans are mostly heparan sulfate proteoglycans (HSPG). Glypican-1, syndecans-1 and -4 were identified using a molecular approach.

9p research12 01-06-2013 43 5   Download

In late larvae of the blowfly, Calliphora vicina, arylphorin and LSP-2 proteins, which belong to the class of hexamerins, are selectively taken up by the fat body from the haemolymph. Hexamerin endocytosis is mediated by a specific membranebound receptor, the arylphorin-binding protein (ABP). Using the two-hybrid technique, we found that the anterior fat body protein (AFP) interacts with the hexamerin receptor.

7p research12 01-06-2013 34 4   Download

To analyze the regulation of Matrix Gla Protein (MGP) gene expression inXenopus laevis, we cloned the xMGPgene and its 5¢ region, determined their molecular organization, and characterized the transcriptional properties of the core promoter. TheXenopusMGP (xMGP) gene is organized into ®ve exons, one more as its mammalian counterparts.

10p research12 23-04-2013 57 3   Download

The present study was conducted on human Jurkat T-cell lines in order to elucidate the role of phospholipase A2in capacitative calcium entry. We have employed thapsigar-gin (TG)that induces increases in [Ca 2+ ] i by emptying the calcium pool of endoplasmic reticulum, followed by capacitative calcium entry. We designed a Ca 2+ free/Ca 2+ reintroduction (CFCR)protocol for the experiments, conducted in Ca 2+ -free medium.

7p tumor12 22-04-2013 33 2   Download

Gelsolin is a multidomain and multifunction protein that nucleates the assembly of filaments and severs them. The activation of gelsolin by calcium is a multistep process involving many calcium binding sites that act to unfold the molecule from a tight structure to a more loose form in which three actin-binding sites become exposed. Low pHis alsoknowntoactivategelsolin, in theabsenceof calciumand this too results in an unfolding of the molecule.

8p tumor12 20-04-2013 42 3   Download

The three-dimensional crystal structure of recombinant annexin Gh1 fromGossypium hirsutum(cotton fibre) has been determined and refined to the finalR-factor of 0.219 at the resolution of 2.1 A ˚ . This plant annexin consists of the typical
annexin fold and is similar to the previously solved bell pepper annexinAnx24(Ca32), but significant differences are seen when compared to the structure of nonplant annexins.

8p fptmusic 16-04-2013 42 2   Download

Calcium metabolism in oysters is a very complicated and highly controlled physiological and biochemical process. However, the regulation of calcium metabolism in oyster is poorly understood. Our previous study showed that calmodulin (CaM) seemed to play a regulatory role in the process of oyster calcium metabolism. In this study, a full-length cDNA encoding a novel calmodulin-like protein (CaLP) with a long C-terminal sequence was identi-fied from pearl oysterPinctada fucata, expressed in Escherichia coliand characterizedin vitro. ...

12p fptmusic 12-04-2013 41 3   Download

Peripheral nerve injury is normally followed by a robust regenerative response. Here we describe the early changes associated with injury from the initial rise in intracellular calcium and the subsequent activation of transcription factors and cytokines leading to an inflammatory reaction, and the expression of growth factors, cytokines, neuropeptides, and other secreted molecules involved in cell-to-cell communication promoting regen-eration and neurite outgrowth.

11p awards 06-04-2013 39 3   Download

The metalloendopeptidase 24.15 (EP24.15) is ubiquitously present in the extracellular environment as a secreted protein. Outside the cell, this enzyme degrades several neuropeptides containing from 5 to 17 amino acids (e.g. gonadotropin releasing hormone, bradykinin, opioids and neuro-tensin). The constitutive secretion of EP24.15 from glioma C6 cells was demonstrated to be stimulated linearly by reduced concentrations of extra-cellular calcium.

15p awards 06-04-2013 29 3   Download

The troponin (Tn) complex is formed by TnC, TnI and TnT and is respon-sible for the calcium-dependent inhibition of muscle contraction. TnC and TnI interact in an antiparallel fashion in which the N domain of TnC binds in a calcium-dependent manner to the C domain of TnI, releasing the inhibitory effect of the latter on the actomyosin interaction. While the crys-tal structure of the core cardiac muscle troponin complex has been deter-mined, very little high resolution information is available regarding the skeletal muscle TnI–TnC complex. ...

0p awards 05-04-2013 35 3   Download

Membrane-associated calcium-independent phospholipase A2c(iPLA2c) contains four potential in-frame methionine start sites (Mancuso, D.J. Jenkins, C.M. & Gross, R.W. (2000)J. Biol. Chem.275, 9937–9945), but the mechanisms regulating the types, amount and subcellular localization of iPLA2c in cells are incompletely understood.

16p awards 05-04-2013 56 3   Download

Mutations in the proteina-tropomyosin (Tm) can cause a disease known as familial hypertrophic cardiomyopathy. In order to understand how such mutations lead to protein dysfunction, three point mutations were introduced into cDNA encoding the human skeletal tropomyosin, and the recombinant Tms were produced at high levels in the yeast Pichia pastoris. Two mutations (A63V and K70T) were located in theN-terminal regionofTmandone (E180G)was located close to the calcium-dependent troponin T binding domain....

9p awards 05-04-2013 54 3   Download

Cytosolic phospholipase A2 -a (cPLA2 -a) is a calcium-activated enzyme involved in agonist-induced arachidonic acid release. In endothelial cells, free arachidonic acid is predominantly converted into prostacyclin, a potent vaso-dilator and inhibitor of platelet activation. As the rate-lim-iting step in prostacyclin production is the generation of free arachidonic acid by cPLA2-a, this enzyme has become an attractive pharmacological target and the focus of many studies.

9p dell39 03-04-2013 40 4   Download

The structure of the Mg 2+ -dependent enzyme human phosphoserine phosphatase (HPSP) was exploited to examine the structural and functional role of the divalent cation in the active site of phosphatases. Most interesting is the biochemical observation that a Ca 2+ ion inhibits the activity of HPSP, even in the presence of added Mg 2+ .The sixfold coordinated Mg 2+ ion present in the active site of HPSP under normal physiological conditions, was replaced by a Ca 2+ ion by using a crystallization conditionwith high concentration of CaCl2(0.7M). ...

7p dell39 03-04-2013 53 3   Download

The interplay among reactive oxygen species (ROS) formation, elevated intracellular calcium concentration and mitochondrial demise is a recurring theme in research focusing on brain pathology, both for acute and chronic neurodegenerative states. However, causality, extent of contribution or the sequence of these events prior to cell death is not yet firmly established.

18p dell39 27-03-2013 45 3   Download

We investigated structural and functional aspects of the first mutation in TNNC1, coding for the calcium-binding subunit (cTnC) of cardiac tropo-nin, which was detected in a patient with hypertrophic cardiomyopathy [Hoffmann B, Schmidt-Traub H, Perrot A, Osterziel KJ & Gessner R (2001) Hum Mut17, 524]. This mutation leads to a leucine–glutamine exchange at position 29 in the nonfunctional calcium-binding site of cTnC.

11p dell39 27-03-2013 51 5   Download