Search results for " AMINO"
showing 10 items of 789 documents
In Vitro and In Vivo Antimalarial Activity Assays of Seeds from Balanites aegyptiaca: Compounds of the Extract Show Growth Inhibition and Activity ag…
2011
Balanites aegyptiaca(Balanitaceae) is a widely grown desert plant with multiuse potential. In the present paper, a crude extract fromB. aegyptiacaseeds equivalent to a ratio of 1 : 2000 seeds to the extract was screened for antiplasmodial activity. The determined IC50value for the chloroquine-susceptiblePlasmodium falciparumNF54 strain was 68.26 . Analysis of the extract by gas chromatography-mass spectrometry detected 6-phenyl-2(H)-1,2,4-triazin-5-one oxime, an inhibitor of the parasitic M18 Aspartyl Aminopeptidase as one of the compounds which is responsible for thein vitroantiplasmodial activity. The crude plant extract had a of 2.35 and showed a dose-dependent response. After depletion…
Cloning and expression of a type IX-like collagen in tissues of the ascidian Ciona intestinalis
2002
Collagens are highly preserved proteins in invertebrates and vertebrates. To identify the collagens in urochordates, the total RNA extracted from the pharynx of the ascidian Ciona intestinalis was hybridized with a heterologous probe specific for the echinoderm Paracentrotus lividus fibrillar type I-like larval collagen. Using this probe, two main bands (i.e. 6 and 2.8 kb mRNA) were observed on Northern blot hybridization. The cDNA library prepared from poly(A)+RNA extracted from pharyngeal tissue was screened and a cDNA that specifies a type IX-like collagen was identified. This molecule presents a conceptual open reading frame for a protein containing 734 amino acids. In particular, we sh…
A major cysteine proteinase, EPB, in germinating barley seeds: structure of two intronless genes and regulation of expression
1996
The barley cysteine proteinase B (EPB) is the main protease responsible for the degradation of endosperm storage proteins providing nitrogenous nutrients to support the growth of young seedlings. The expression of this enzyme is induced in the germinating seeds by the phytohormone, gibberellin, and suppressed by another phytohormone, abscisic acid. In situ hybridization experiments indicate that EPB is expressed in the scutellar epithelium within 24 h of seed germination, but the aleurone tissue surrounding the starchy endosperm eventually becomes the main tissue expressing this enzyme. The EPB gene family of barley consists of two very similar genes, EPB1 and EPB2, both of which have been …
The dnaK operon of Streptomyces coelicolor encodes a novel heat-shock protein which binds to the promoter region of the operon
1995
Transcriptional studies have demonstrated that the dnaK gene of Streptomyces coelicolor A3(2) is contained within a 4.3 kb operon. The operon is transcribed from a single (transiently) heat-inducible promoter, dnaKp, that resembles the typical vegetative (sigma 70-recognized) eubacterial consensus promoter sequence. dnaK transcription was found to be heat-inducible at all stages of development in surface-grown cultures. In addition, at the normal growth temperature of 30 degrees C, dnaK transcript levels were shown to vary at different stages of development, being more abundant in young germinating cultures and in mycelium undergoing sporogenesis. The nucleotide sequence of the dnaK operon …
Characterization and DNA-binding properties of GRF, a novel monomeric binding orphan receptor related to GCNF and betaFTZ-F1
1999
0014-2956 (Print) Comparative Study Journal Article Research Support, Non-U.S. Gov't; A PCR approach has been used to isolate, from Bombyx mori, a cDNA encoding a novel orphan receptor (GRF) that is most closely related to Bombyx betaFTZ-F1 and to the vertebrate germ cell nuclear factor. The major GRF mRNA is detected in most tissues as an 8-kb transcript whose amount follows the circulating ecdysteroid concentration with a delay. The expression pattern of GRF is similar to that of the Bombyx homologue of the Drosophila early-late gene DHR3, and precedes that of betaFTZ-F1 in all stages and tissues examined. The GRF protein is thus likely to be required in many tissues, but in a temporally …
Ethylene modulates gene expression in cells of the marine sponge Suberites domuncula and reduces the degree of apoptosis.
1999
Sponges (phylum Porifera) live in an aqueous milieu that contains dissolved organic carbon. This is degraded photochemically by ultraviolet radiation to alkenes, particularly to ethylene. This study demonstrates that sponge cells (here the demosponge Suberites domuncula has been used), which have assembled to primmorphs, react to 5 microM ethylene with a significant up-regulation of intracellular Ca(2+) concentration and with a reduction of starvation-induced apoptosis. In primmorphs from S. domuncula the expression of two genes is up-regulated after exposure to ethylene. The cDNA of the first gene (SDERR) isolated from S. domuncula encodes a potential ethylene-responsive protein, termed ER…
Insensitivity to Aβ42-lowering Nonsteroidal Anti-inflammatory Drugs and γ-Secretase Inhibitors Is Common among Aggressive Presenilin-1 Mutations
2007
Abeta42-lowering nonsteroidal anti-inflammatory drugs (NSAIDs) constitute the founding members of a new class of gamma-secretase modulators that avoid side effects of pan-gamma-secretase inhibitors on NOTCH processing and function, holding promise as potential disease-modifying agents for Alzheimer disease (AD). These modulators are active in cell-free gamma-secretase assays indicating that they directly target the gamma-secretase complex. Additional support for this hypothesis was provided by the observation that certain mutations in presenilin-1 (PS1) associated with early-onset familial AD (FAD) change the cellular drug response to Abeta42-lowering NSAIDs. Of particular interest is the P…
Structure and expression of clustered P element homologues in Drosophila subobscura and Drosophila guanche
1995
Abstract Sequence relationships and functional aspects were analysed in the P element homologues of Drosophila subobscura (Ds) and D. guanche (Dg) . In both species, the P homologues are clustered at a single genomic position. They lack the characteristic terminal structures of actively transposing P elements, but they have the coding capacity for a 66-kDa ‘repressor-like’ protein. Two different types of cluster units (G-type and A-type) can be distinguished. The A-type unit, which is present in multiple copies, is transcribed in adult flies. In contrast, the G-type unit has a much lower copy number and is apparently not expressed. In Dg , the isolated G-type sequence carries a 420-bp inser…
bilbo, a non-LTR retrotransposon of Drosophila subobscura: a clue to the evolution of LINE-like elements in Drosophila
1997
We used the repetitive character of transposable elements to isolate a non-LTR retrotransposon in Drosophila subobscura. bilbo, as we have called it, has homology to TRIM and LOA elements. Sequence analysis showed a 5' untranslated region (UTR), an open reading frame (ORF) with no RNA-binding domains, a downstream ORF that had structural homology to that of the I factor, and, finally, a 3' UTR which ended in several 5-nt repeats. The results of our phylogenetic and structural analyses shed light on the evolution of Drosophila non-LTR retrotransposons and support the hypothesis that an ancestor of these elements was structurally complex.
N-Acetilglutamato sintasa : correlaciones estructura-función
2013
La N–acetilglutamato sintasa (NAGS) cataliza la formación del N-acetilglutamato (NAG) usando como sustratos glutamato y acetil-CoA. En microorganismos y plantas, esta reacción es el primer paso de la ruta de biosíntesis de la arginina, mientras que, en animales, está implicada en el control del ciclo de la urea, ya que el NAG es un activador esencial de la carbamilfosfato sintetasa I encargada de la formación del carbamilfosfato, intermedio en el ciclo de la urea. En humanos, la deficiencia de NAGS produce hiperamonemia y, desde 2002, año en el que el gen de la NAGS humana fue identificado, varias mutaciones han sido publicadas. Esta tesis trata, principalmente, de la NAGS bacteriana clásic…