Search results for "sequence data"
showing 10 items of 1952 documents
Ovulation-inducing activity of luliberin (LHRH) complexed by copper(II), nickel(II), and zinc(II) ions.
1990
We have shown that the complexation of luteinizing hormone releasing hormone, luliberin (LHRH), a hypothalamic neurohormone, by Cu(II), Ni(II), and Zn(II) may affect its basic, ovulation-inducing potency in the dose responsive manner. Some explanation of the obtained results are offered here.
Mutation of the oxaloacetate decarboxylase gene of Lactococcus lactis subsp. lactis impairs the growth during citrate metabolism
2007
; Aims: Citrate metabolism generates metabolic energy through the generation of a membrane potential and a pH gradient. The purpose of this work was to study the influence of oxaloacetate decarboxylase in citrate metabolism and intracellular pH maintenance in relation to acidic conditions. Methods and Results: A Lactococcus lactis oxaloacetate decarboxylase mutant [ILCitM (pFL3)] was constructed by double homologous recombination. During culture with citrate, and whatever the initial pH, the growth rate of the mutant was lower. In addition, the production of diacetyl and acetoin was altered in the mutant strain. However, our results indicated no relationship with a change in the maintenanc…
Differential Expression of the Demosponge (Suberites domuncula) Carotenoid Oxygenases in Response to Light: Protection Mechanism Against the Self-Pro…
2012
The demosponge Suberites domuncula has been described to contain high levels of a proteinaceous toxin, Suberitine, that displays haemolytic activityIn the present study this 7–8 kDa polypeptide has been isolated and was shown to exhibit also cytotoxic effects on cells of the same species. Addition of retinal, a recently identified metabolite of β-carotene that is abundantly present in S. domuncula was found to reduce both the haemolytic and the cell toxic activity of Suberitine at a molar ratio of 1:1. Spectroscopic analyses revealed that the interaction between β-carotene and Suberitine can be ascribed to a reversible energy transfer reaction. The enzyme that synthesises retinal in the spo…
Modification of the proteolytic fragmentation pattern upon oxidation of cysteines from ribulose 1,5-bisphosphate carboxylase/oxygenase.
2003
The proteolytic susceptibility of the native CO 2 -fixing photosynthetic enzyme ribulose 1,5-bisphosphate carboxylase/oxygenase (EC 4.1.1.39, Rubisco) has been shown to increase in vitro after oxidative treatments that affect cysteine thiols. A limited incubation of oxidized (pretreated with the disulfide cystamine) Rubisco from Chlamydomonas reinhardtii with subtilisin or proteinase K generated fragments of molecular mass about 53 kDa (band I in SDS-PAGE) and 47 kDa (band II) derived from the large subunit (55 kDa) of the enzyme. In contrast, proteolysis of the reduced Rubisco (pretreated with the free thiol cysteamine) produced only the 53 kDa band. The same fragmentation pattern was repr…
Pmarg-pearlin is a matrix protein involved in nacre framework formation in the pearl oyster Pinctada margaritifera.
2011
11 pages; International audience; The shell of pearl oysters is organized in multiple layers of CaCO(3) crystallites packed together in an organic matrix. Relationships between the components of the organic matrix and mechanisms of nacre formation currently constitute the main focus of research into biomineralization. In this study, we characterized the pearlin protein from the oyster Pinctada margaritifera (Pmarg); this shares structural features with other members of a matrix protein family, N14/N16/pearlin. Pmarg pearlin exhibits calcium- and chitin-binding properties. Pmarg pearlin transcripts are distinctively localized in the mineralizing tissue responsible for nacre formation. More s…
Stappia alba sp. nov., isolated from Mediterranean oysters
2005
Abstract Three bacterial strains isolated from oysters recovered at the Spanish Mediterranean coast have been phenotypically and genetically characterized. The results of the phylogenetic analysis based on almost complete 16S rDNA sequences clustered all three strains together with 99.9% average sequence similarity and situated them in the neighbourhood of the genera Stappia , Roseibium and Pannonibacter , Stappia aggregata being their closest neighbour with sequence similarities between 98.8% and 98.9%. DNA–DNA hybridization experiments using DNA of strains 5OM6 T and S. aggregata CECT 4269 T as reference DNAs confirmed the independent status at species level of the oyster isolates. Phenot…
Retama species growing in different ecological-climatic areas of northeastern Algeria have a narrow range of rhizobia that form a novel phylogenetic …
2009
International audience; Sixty-seven isolates were isolated from nodules collected on roots of Mediterranean shrubby legumes Retama raetam and Retama sphaerocarpa growing in seven ecological-climatic areas of northeastern Algeria. Genetic diversity of the Retama isolates was analyzed based on genotyping by restriction fragment length polymorphism of PCR-amplified fragments of the 16S rRNA gene, the intergenic spacer (IGS) region between the 16S and 23S rRNA genes (IGS), and the symbiotic genes nifH and nodC. Eleven haplotypes assigned to the Bradyrhizobium genus were identified. Significant biogeographical differentiation of the rhizobial populations was found, but one haplotype was predomin…
Combined Therapy of Interferon Plus Ribavirin Promotes Multiple Adaptive Solutions in Hepatitis C Virus
2009
Hepatitis C virus (HCV) presents several regions involved potentially in evading antiviral treatment and host immune system. Two regions, known as PKR-BD and V3 domains, have been proposed to be involved in resistance to interferon. Additionally, hypervariable regions in the envelope E2 glycoprotein are also good candidates to participate in evasion from the immune system. In this study, we have used a cohort of 22 non-responder patients to combined therapy (interferon alpha-2a plus ribavirin) for which samples obtained just before initiation of therapy and after 6 or/and 12 months of treatment were available. A range of 25-100 clones per patient, genome region and time sample were obtained…
The yeast inositol monophosphatase is a lithium- and sodium-sensitive enzyme encoded by a non-essential gene pair
1999
Inositol monophosphatases (IMPases) are lithium-sensitive enzymes that participate in the inositol cycle of calcium signalling and in inositol biosynthesis. Two open reading frames (YHR046c and YDR287w) with homology to animal and plant IMPases are present in the yeast genome. The two recombinant purified proteins were shown to catalyse inositol-1-phosphate hydrolysis sensitive to lithium and sodium. A double gene disruption had no apparent growth defect and was not auxotroph for inositol. Therefore, lithium effects in yeast cannot be explained by inhibition of IMPases and inositol depletion, as suggested for animal systems. Overexpression of yeast IMPases increased lithium and sodium toler…
The stability and functional properties of proteoliposomes mixed with dextran derivatives bearing hydrophobic anchor groups
1992
Liposomes composed of Escherichia coli phospholipid were coated with polysaccharides bearing hydrophobic palmitoyl anchors. The effect on the stability of liposomes without or with integral membrane proteins was investigated. A high concentration of hydrophobized dextrans protected the liposomes against detergent degradation, decreased the fluidity of the membranes, prevented fusion of the liposomes and enhanced their stability. Proteoliposomes containing beef heart cytochrome-c oxidase and the lactose transport carrier of E. coli were similarly affected by coating with the dextrans. Under these conditions both membrane proteins were still active. Long-term stability of the coated liposomes…