Search results for "SAC"
showing 10 items of 3337 documents
Yeast Translation Elongation Factor eIF5A Expression Is Regulated by Nutrient Availability through Different Signalling Pathways
2020
Translation elongation factor eIF5A binds to ribosomes to promote peptide bonds between problematic amino acids for the reaction like prolines. eIF5A is highly conserved and essential in eukaryotes, which usually contain two similar but differentially expressed paralogue genes. The human eIF5A-1 isoform is abundant and implicated in some cancer types
Mitotic Recombination and Genetic Changes in Saccharomyces cerevisiae during Wine Fermentation
2000
Natural strains of Saccharomyces cerevisiae are prototrophic homothallic yeasts that sporulate poorly, are often heterozygous, and may be aneuploid. This genomic constitution may confer selective advantages in some environments. Different mechanisms of recombination, such as meiosis or mitotic rearrangement of chromosomes, have been proposed for wine strains. We studied the stability of the URA3 locus of a URA3/ura3 wine yeast in consecutive grape must fermentations. ura3/ura3 homozygotes were detected at a rate of 1 x 10(-5) to 3 x 10(-5) per generation, and mitotic rearrangements for chromosomes VIII and XII appeared after 30 mitotic divisions. We used the karyotype as a meiotic marker an…
Los truncamientos en la conversación coloquial: estudio de las huellas de formulación discursiva desde un modelo de unidades de lo oral
2019
Una de las principales características de la conversación coloquial, por oposición a otro tipo de géneros discursivos, es que se produce espontáneamente y sobre la marcha, es decir, sin planificación previa (Beinhauer 1963[1929], Ochs 1979, Narbona 1992, Briz 1998, entre otros). La formulación espontánea del coloquio deja toda una serie de trazas o huellas en el discurso resultante –rupturas, auto-correcciones, cambios abruptos de construcciones, segmentos truncados– que denominamos fenómenos formulativos, ya que permiten entrever los procesos de formulación que subyacen a la construcción del discurso sobre la marcha. La presente investigación se centra en el estudio de un tipo de fenómeno …
A novel rat CVB1-VP1 monoclonal antibody 3A6 detects a broad range of enteroviruses
2018
AbstractEnteroviruses (EVs) are common RNA viruses that cause diseases ranging from rash to paralytic poliomyelitis. For example, EV-A and EV-C viruses cause hand-foot and mouth disease and EV-B viruses cause encephalitis and myocarditis, which can result in severe morbidity and mortality. While new vaccines and treatments for EVs are under development, methods for studying and diagnosing EV infections are still limited and therefore new diagnostic tools are required. Our aim was to produce and characterize new antibodies that work in multiple applications and detect EVs in tissues and in vitro. Rats were immunized with Coxsackievirus B1 capsid protein VP1 and hybridomas were produced. Hybr…
All-atom simulations disentangle the functional dynamics underlying gene maturation in the intron lariat spliceosome
2018
The spliceosome (SPL) is a majestic macromolecular machinery composed of five small nuclear RNAs and hundreds of proteins. SPL removes noncoding introns from precursor messenger RNAs (pre-mRNAs) and ligates coding exons, giving rise to functional mRNAs. Building on the first SPL structure solved at near–atomic-level resolution, here we elucidate the functional dynamics of the intron lariat spliceosome (ILS) complex through multi-microsecond-long molecular-dynamics simulations of ∼1,000,000 atoms models. The ILS essential dynamics unveils (i) the leading role of the Spp42 protein, which heads the gene maturation by tuning the motions of distinct SPL components, and (ii) the critical particip…
Size- and Structure-Selective Noncovalent Recognition of Saccharides by Tetraethyl and Tetraphenyl Resorcinarenes in the Gas Phase
2008
The noncovalent complexation of tetraethyl and tetraphenyl resorcinarenes with mono-, di-, and oligosaccharides was studied with negative-polarization electrospray ionization quadrupole ion trap and electrospray ionization Fourier-transform ion cyclotron resonance mass-spectrometric analysis. The saccharides formed 1:1 complexes with deprotonated resorcinarenes, which exhibited clear size and structure selectivity in their complexation. In the case of the monosaccharides, hexoses formed much more abundant and kinetically stable complexes than pentoses or deoxyhexoses. A comparison of the mono-, di-, and oligosaccharides revealed that both the relative abundance and stability of the complexe…
Picomolar inhibition of cholera toxin by a pentavalent ganglioside GM1os-calix[5]arene
2013
Cholera toxin (CT), the causative agent of cholera, displays a pentavalent binding domain that targets the oligosaccharide of ganglioside GM1 (GM1os) on the periphery of human abdominal epithelial cells. Here, we report the first GM1os-based CT inhibitor that matches the valency of the CT binding domain (CTB). This pentavalent inhibitor contains five GM1os moieties linked to a calix[5]arene scaffold. When evaluated by an inhibition assay, it achieved a picomolar inhibition potency (IC50 = 450 pM) for CTB. This represents a significant multivalency effect, with a relative inhibitory potency of 100000 compared to a monovalent GM1os derivative, making GM1os-calix[5]arene one of the most potent…
Comparison of Protective Effects against Reactive Oxygen Species of Mononuclear and Dinuclear Cu(II) Complexes with N-Substituted Benzothiazolesulfon…
2005
Copper(II) complexes of N-benzothiazolesulfonamides (HL1=N-2-(4-methylphenylsulfamoyl)-6-nitro-benzothiazole, HL2=N-2-(phenylsulfamoyl)-6-chloro-benzothiazole, and HL3=N-2-(4-methylphenylsulfamoyl)-6-chloro-benzothiazole) with ammonia have been synthesized and characterized. The crystal structures of the [Cu(L1)2(NH3)2].2MeOH, [Cu(L2)2(NH3)2], and [Cu(L3)2(NH3)2] compounds have been determined. Compounds and present a distorted square planar geometry. In both compounds the metal ion is coordinated by two benzothiazole N atoms from two sulfonamidate anions and two NH3 molecules. Complex is distorted square-pyramidal. The Cu(II) ion is linked to the benzothiazole N and sulfonamidate O atoms o…
A new evolutionary paradigm for the Parkinson disease gene DJ-1.
2006
The DJ-1 gene is extensively studied because of its involvement in familial Parkinson disease. DJ-1 belongs to a complex superfamily of genes that includes both prokaryotic and eukaryotic representatives. We determine that many prokaryotic groups, such as proteobacteria, cyanobacteria, spirochaetes, firmicutes, or fusobacteria, have genes, often incorrectly called "Thij," that are very close relatives of DJ-1, to the point that they cannot be clearly separated from the eukaryotic DJ-1 genes by phylogenetic analyses of their sequences. In addition, and contrary to a previous study that suggested that DJ-1 genes were animal specific, we show that DJ-1 genes are found in at least 5 of the 6 ma…
Molecular dynamics simulation of sucrose- and trehalose-coated carboxy-myoglobin
2005
We performed a room temperature molecular dynamics (MD) simulation on a system containing 1 carboxy-myoglobin (MbCO) molecule in a sucrose–water matrix of identical composition (89% [sucrose/(sucrose + water)] w/w) as for a previous trehalose–water–MbCO simulation (Cottone et al., Biophys J 2001;80:931–938). Results show that, as for trehalose, the amplitude of protein atomic mean-square fluctuations, on the nanosecond timescale, is reduced with respect to aqueous solutions also in sucrose. A detailed comparison as a function of residue number evidences mobility differences along the protein backbone, which can be related to a different efficacy in bioprotection. Different heme pocket struc…