Search results for "OxyR"
showing 10 items of 216 documents
An oxidatively damaged G-quadruplex/hemin DNAzyme.
2020
International audience; Oxidative damage of guanine to 8-oxoguanine triggers a partial and variable loss of G-quadruplex/hemin DNAzyme activity and provides clues to the mechanistic origins of DNAzyme deactivation, which originates from an interplay between decreased G-quadruplex stability, lower hemin affinity and a modification of the nature of hemin binding sites.
Skin-derived macrophages from Leishmania major-susceptible mice exhibit interleukin-12- and interferon-gamma-independent nitric oxide production and …
2002
Co-administration of CpG-containing immunostimulatory oligodeoxynucleotides and parasite antigen protects susceptible BALB/c mice from otherwise progressive infection with Leishmania major. Although the protective effect of CpG-containing immunostimulatory oligodeoxynucleotides is clearly dependent on endogenous interleukin-12 and interferon-gamma production, the source of these Th1-promoting cytokines in infected mice is unknown. In contrast to macrophages from Leishmania-resistant C57BL/6 mice, macrophages from susceptible BALB/c mice are hyporesponsive to stimulation with lipopolysaccharide and interferon-gamma. While studying interactions of various antigen-presenting cells with Leishma…
Production of biologically active light chain of tetanus toxin inEscherichia coli
1993
AbstractThe activity of the light (L) chain of tetanus toxin, and of mutants constructed by site-directed mutagenesis, was studied by expression and purification of the proteins from E. coli. Wild-type recombinant L chain (pTet87) was active in the inhibition of exocytosis from cultured bovine adrenal chromaffin cells, although at a level 5–15% of that of L chain purified from tetanus toxin. L chain mutants which terminated at Leu-438 (pTet89), or which contained a Cys-to-Ser mutation at residue 439 (pTet88) were equally as active as the full-length recombinant protein. The reduced activity of pTet87 L chain correlated with C-terminal proteolysis of the protein upon purification. A tryptic …
Molecular Analysis of the Androgen Receptor Gene in 52 Patients with Complete or Partial Androgen Insensitivity Syndrome: A Collaborative Study
1992
In patients with androgen insensitivity syndrome (AIS), RFLP study of the androgen receptor gene made it possible to analyze whether deletions or mutations could be responsible for abnormalities in androgen responsiveness. We studied RFLPs of DNA from 25 46,XY patients with partial AIS (PAIS), defined as a concentration of androgen receptor in genital-skin fibroblasts less than 340 fmol/mg DNA, and DNA from 27 46,XY patients with complete AIS (CAIS) with no detectable androgen receptor site. DNA samples were digested with BamHI, EcoRI, HindIII and TaqI restriction enzymes and hybridized with three cDNA probes covering the three domains of the androgen receptor. When we had the maternal and …
Medicago species affect the community composition of arbuscular mycorrhizal fungi associated with roots
2007
National audience; The symbiosis between plants and arbuscular mycorrhizal fungi (AMF) is ancient and involves 80% of terrestrial plant families. The symbiotic association between AMF and plants was described to be non specific. However, AMF were reported to influence plant community diversity and productivity. On the other way, the effect of plant genotypes belonging to closely related species on AMF diversity has not been explored so far. The aim of this work was to assess the impact of four different Medicago species, M. laciniata, M. murex, M. polymorpha and M. truncatula cv. Jemalong J5, on the composition of AM fungal community, when cultivated in a silty-thin clay soil (Mas d’Imbert,…
Preparation of degraded human DNA under controlled conditions
2003
Abstract DNA typing through analysis of short tandem repeats (STRs) and mitochondrial DNA (mtDNA) by means of the polymerase chain reaction (PCR) and sequencing are the common methods for the forensic identification of persons and reconstruction of kinship, especially when skeletal human remains have to be analyzed. Furthermore, samples typically found at crime scenes may be both quantitatively and qualitatively inadequate since they may contain very scarce and often degraded DNA due to exposure to heat, light, humidity, and microorganisms. In order to improve the performance of STR typing technology in those cases where DNA availability is limited, it would be desirable to have a source of…
DNA interaction of CuII, NiII and ZnII functionalized salphen complexes: studies by linear dichroism, gel electrophoresis and PCR.
2013
The interaction of salphen-type NiII, CuII and ZnII complexes with native DNA was investigated by exploiting linear dichroism experiments. The NiII complex behaves as a typical intercalator, binding strongly and stiffening and unwinding the DNA. The strength of the DNA interaction is slightly weaker for the copper complex and much weaker for the zinc complex. Plasmid-DNA gel electrophoresis experiments indicated that while CuII and ZnII complexes do not induce the unwinding of supercoiled DNA, the NiII complex has a nuclease activity without the addition of external agents. On the other hand, as shown in the PCR assays, we demonstrate that, at the used concentrations, only the CuII complex …
The membrane distal half of gp130 is responsible for the formation of a ternary complex with IL-6 and the IL-6 receptor
1995
AbstractGp130 is the signal transducing subunit of the interleukin-6 receptor. Signaling is initiated by the complex formation of gp130 with IL-6 bound to the IL-6 receptor (IL-6R). We have subdivided the extracellular domain of gp130 in two parts and expressed the mutant proteins as soluble IgG fusion proteins in COS-7 cells. By studying the formation of the ternary complex we show that the membrane distal half of gp130 which contains a cytokine receptor domain is responsible for the interaction with the IL-6/IL-6R complex. Interestingly this is the same region which is believed to be involved in specific recognition of the related cytokines LIF, OM, and probably also of CNTF and IL-11.
Chromatin structure of the 5′ flanking region of the yeastLEU2 gene
1989
The chromatin structure of theLEU2 gene and its flanks has been studied by means of nuclease digestion, both with micrococcal nuclease and DNase I. The gene is organized in an array of positioned nucleosomes. Within the promoter region, the nucleosome positioning places the regulatory sequences, putative TATA box and upstream activator sequence outside the nucleosomal cores. The tRNA3 Leu gene possesses a characteristic structure and is protected against nucleases. Most of the 5′ flank is sensitive to DNase I digestion, although no clear hypersensitive sites were found. The chromatin structure is independent of either the transcriptional state of the gene or the chromosomal or episomal loca…
Structural basis and effect of copper(II) complexes with 4-oxo-thiazolidine ligands on DNA binding and nuclease activity
2020
Abstract Seven novel Copper(II) complexes, namely [Cu(Am4DHotaz)(H2O)2](ClO4) (1), [Cu(Am4DHotaz)(NO3)(MeOH)]·H2O (2), [Cu(Am4Motaz)2(H2O)](ClO4)2·0.83H2O (3), [Cu(Am4Motaz)2(NO3)]NO3·MeOH (4), [Cu(Am4Eotaz)2(NO3)]3(NO3)3·2H2O (5), [Cu(Am4Eotaz)2(ClO4)](ClO4) (6) and [Cu(Am4Eotaz)(ClO4)(H2O)](ClO4) (6a) (HAm4DHotaz = N′-(4-oxothiazolidin-2-ylidene)pyridine-2-carbohydrazonamide, Am4Motaz = N′-(3-methyl-4-oxothiazolidin-2-ylidene)pyridine-2-carbohydrazonamide and Am4Eotaz = N′-(3-ethyl-4-oxothiazolidin-2-ylidene)pyridine-2-carbohydrazonamide), have been successfully synthesized and characterized by several physicochemical techniques and, for 1–6 complexes, single crystal X-ray diffraction. Ha…