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121.
Abid G Muhovski Y Jacquemin JM Mingeot D Sassi K Toussaint A Baudoin JP 《Molecular biology reports》2012,39(2):1133-1143
A full-length cDNA encoding common bean (Phaseolus vulgaris L.) sucrose synthase (designated as Pv_BAT93 Sus), which catalyses the synthesis and cleavage of sucrose, was isolated from
seeds at 15 days after pollination (DAP) by rapid amplification of cDNA ends (RACE). The full-length cDNA of Pv_BAT93 Sus
had a 2,418 bp open reading frame (ORF) encoding a protein of 806 amino acid residues. Sequence comparison analysis showed
that Pv_BAT93 Sus was very similar to several members of the sucrose synthase family of other plant species. Tissue expression
pattern analysis showed that Pv_BAT93 Sus was expressed in leaves, flowers, stems, roots, cotyledons, and particularly during
seed development. Expression studies using in situ hybridization revealed altered spatial and temporal patterns of Sus expression
in the EMS mutant relative to wild-type and confirmed Sus expression in common bean developing seeds. The expression and accumulation
of Sus mRNA was clearly shown in several tissues, such as the suspensor and embryo, but also in the transfer cells and endothelium.
The results highlight the diverse roles that Sus might play during seed development in common bean. 相似文献
122.
Development of a measles vaccine production process in MRC-5 cells grown on Cytodex1 microcarriers and in a stirred bioreactor 总被引:1,自引:0,他引:1
Measles vaccination remains the most efficient way to control the spread of the virus. This work focuses on the production
of a measles vaccine using stirred conditions as an advanced option for process scale up. Non-porous Cytodex 1 microcarriers
were used to support MRC-5 cell growth in suspension cultures. Virus replication was first optimized in spinner flasks, and
the effects of various operational parameters were investigated. Cell infection with AIK-C measles strain at an MOI (multiplicity
of infection) of 0.005, without glucose regulation and in M199 medium, resulted in a virus titer of 106.25 TCID50 (median tissue culture infective dose)/ml. To optimize the production process in a 7-l bioreactor, we carried out various
perfused cultures using minimum essential medium (MEM) + 5% FCS diluted with phosphate-buffered saline (PBS). We achieved
a high cell density level (4.1 × 106 cells/ml) with an efficient use of the medium when MEM + 5% FCS diluted with PBS at 25% was used during the cell amplification
step. Optimization of measles production in MRC-5 cells grown on Cytodex 1 beads in a 7-l bioreactor showed that perfusion
was the most efficient when compared to repeated-batch culture. Perfusion at a rate of 0.25 V (reactor volume)/day showed
the highest specific productivity (1.6 IVP [infectious virus particle] cell−1 day−1). Testing of several stabilizers containing pharmaceutically improved components such as sugars, amino acids, and charged
ions showed that the formulation composed of sucrose and MgCl2, led to the maintenance of the infectivity of the AIK-C measles virus strain to a significant level, when stored at +28 °C,
+4 °C and −60 °C. 相似文献
123.
Guo-Shu Wang Hartmut Grammel Khaled Abou-Aisha Rudolf S?gesser Robin Ghosh 《Applied and environmental microbiology》2012,78(20):7205-7215
The biosynthesis of the major carotenoid spirilloxanthin by the purple nonsulfur bacterium Rhodospirillum rubrum is thought to occur via a linear pathway proceeding through phytoene and, later, lycopene as intermediates. This assumption is based solely on early chemical evidence (B. H. Davies, Biochem. J. 116:93–99, 1970). In most purple bacteria, the desaturation of phytoene, catalyzed by the enzyme phytoene desaturase (CrtI), leads to neurosporene, involving only three dehydrogenation steps and not four as in the case of lycopene. We show here that the chromosomal insertion of a kanamycin resistance cassette into the crtC-crtD region of the partial carotenoid gene cluster, whose gene products are responsible for the downstream processing of lycopene, leads to the accumulation of the latter as the major carotenoid. We provide spectroscopic and biochemical evidence that in vivo, lycopene is incorporated into the light-harvesting complex 1 as efficiently as the methoxylated carotenoids spirilloxanthin (in the wild type) and 3,4,3′,4′-tetrahydrospirilloxanthin (in a crtD mutant), both under semiaerobic, chemoheterotrophic, and photosynthetic, anaerobic conditions. Quantitative growth experiments conducted in dark, semiaerobic conditions, using a growth medium for high cell density and high intracellular membrane levels, which are suitable for the conventional industrial production in the absence of light, yielded lycopene at up to 2 mg/g (dry weight) of cells or up to 15 mg/liter of culture. These values are comparable to those of many previously described Escherichia coli strains engineered for lycopene production. This study provides the first genetic proof that the R. rubrum CrtI produces lycopene exclusively as an end product. 相似文献
124.
Belghith KS Dahech I Hamden K Feki A Mejdoub H Belghith H 《International journal of biological macromolecules》2012,50(4):1070-1074
Levan polysaccharide, a type of fructan, has been shown to have industrial applications as a new industrial gum in the fields of cosmetics, foods like dietary fiber and pharmaceutical goods. The objective of this current study was to investigate the possible hypolipidemic and antioxidative effects of levan in rats fed with a high-cholesterol diet. Animals were allocated into four groups of six rats each: a normal diet group (Control), normal rats received levan (L), a high-cholesterol diet group (Chol) and a high-cholesterol diet with a daily dose of levan equivalent to 5%. Treated hypercholesterolemic rats were administrated with levan in drinking water through oral gavage for 60 days. After the treatment period, the plasma antioxidant enzymes and lipid profiles were determined. Our results show that treatment with levan polysaccharide positively changed plasma antioxidant enzyme activities and lipid profiles (total cholesterol, HDL-cholesterol, LDL-cholesterol and triglycerides) in cholesterol-rats, and thus may have potential hypolipidemic and antioxidant effects. Levan could protect against oxidative stress linked atherosclerosis and decrease the atherogenic index. 相似文献
125.
126.
Santosh S. Chobe Bhaskar S. Dawane Khaled M. Tumbi Prajwal P. Nandekar Abhay T. Sangamwar 《Bioorganic & medicinal chemistry letters》2012,22(24):7566-7572
The DNA molecule is a target for plethora of anticancer and antiviral drugs that forms covalent and non-covalent adducts with major or minor groove of DNA. In present study we synthesized series of novel Pyrazolo [1,5-a]pyrimidine derivatives. The newly synthesized compounds were characterized by elemental analysis, IR, 1H NMR, and mass spectral data. The selected compounds were studied for interaction with Calf thymus DNA (CT-DNA) using electronic spectra, viscosity measurement and thermal denaturation studies. Further, molecular interactions were revealed for compound IIIa and IVa by computational methodologies. The preferred mode of ligand binding with double helical DNA as well as preferable DNA groove were explored by molecular docking in different DNA models. 相似文献
127.
Eloualid A Rhaissi H Reguig A Bounaceur S El Houate B Abidi O Charif M Louanjli N Chadli E Barakat A Bashamboo A McElreavey K Rouba H 《PloS one》2012,7(4):e34902
Infertility affects around 1 in 10 men and in most cases the cause is unknown. The Y chromosome plays an important role in spermatogenesis and specific deletions of this chromosome, the AZF deletions, are associated with spermatogenic failure. Recently partial AZF deletions have been described but their association with spermatogenic failure is unclear. Here we screened a total of 339 men with idiopathic spermatogenic failure, and 256 normozoospermic ancestry-matched men for chromosome microdeletions including AZFa, AZFb, AZFc, and the AZFc partial deletions (gr/gr, b1/b3 and b2/b3).AZFa and AZFc deletions were identified in men with severe spermatogenic failure at similar frequencies to those reported elsewhere. Gr/gr deletions were identified in case and control populations at 5.83% and 6.25% respectively suggesting that these deletions are not associated with spermatogenic failure. However, b2/b3 deletions were detected only in men with spermatogenic failure and not in the normospermic individuals. Combined with our previous data this shows an association of the b2/b3 deletion (p = 0.0318) with spermatogenic failure in some populations. We recommend screening for this deletion in men with unexplained spermatogenic failure. 相似文献
128.
Shirley Haun Lu Sun Satanay Hubrack David Yule Khaled Machaca 《Channels (Austin, Tex.)》2012,6(5):379-384
The Ins(1,4,5)P3 receptor acts as a central hub for Ca2+ signaling by integrating multiple signaling modalities into Ca2+ release from intracellular stores downstream of G-protein and tyrosine kinase-coupled receptor stimulation. As such, the Ins(1,4,5)P3 receptor plays fundamental roles in cellular physiology. The regulation of the Ins(1,4,5)P3 receptor is complex and involves protein-protein interactions, post-translational modifications, allosteric modulation, and regulation of its sub-cellular distribution. Phosphorylation has been implicated in the sensitization of Ins(1,4,5)P3-dependent Ca2+ release observed during oocyte maturation. Here we investigate the role of phosphorylation at T-930, a residue phosphorylated specifically during meiosis. We show that a phosphomimetic mutation at T-930 of the rat Ins(1,4,5)P3 receptor results in decreased Ins(1,4,5)P3-dependent Ca2+ release and lowers the Ins(1,4,5)P3 binding affinity of the receptor. These data, coupled to the sensitization of Ins(1,4,5)P3-dependent Ca2+ release during meiosis, argue that phosphorylation within the coupling domain of the Ins(1,4,5)P3 receptor acts in a combinatorial fashion to regulate Ins(1,4,5)P3 receptor function. 相似文献
129.
McCarthy JS Lustigman S Yang GJ Barakat RM García HH Sripa B Willingham AL Prichard RK Basáñez MG 《PLoS neglected tropical diseases》2012,6(4):e1601
Diagnostic tools appropriate for undertaking interventions to control helminth infections are key to their success. Many diagnostic tests for helminth infection have unsatisfactory performance characteristics and are not well suited for use in the parasite control programmes that are being increasingly implemented. Although the application of modern laboratory research techniques to improve diagnostics for helminth infection has resulted in some technical advances, uptake has not been uniform. Frequently, pilot or proof of concept studies of promising diagnostic technologies have not been followed by much needed product development, and in many settings diagnosis continues to rely on insensitive and unsatisfactory parasitological or serodiagnostic techniques. In contrast, PCR-based xenomonitoring of arthropod vectors, and use of parasite recombinant proteins as reagents for serodiagnostic tests, have resulted in critical advances in the control of specific helminth parasites. The Disease Reference Group on Helminths Infections (DRG4), established in 2009 by the Special Programme for Research and Training in Tropical Diseases (TDR) was given the mandate to review helminthiases research and identify research priorities and gaps. In this review, the diagnostic technologies relevant to control of helminth infections, either available or in development, are reviewed. Critical gaps are identified and opportunities to improve needed technologies are discussed. 相似文献
130.
The prefrontal cortex (PFC) develops from birth through late adolescence. This extended developmental trajectory provides many opportunities for experience to shape the structure and function of the PFC. To date, a few studies have reported links between parental socioeconomic status (SES) and prefrontal function in childhood, raising the possibility that aspects of environment associated with SES impact prefrontal function. Considering that behavioral measures of prefrontal function are associated with learning across multiple domains, this is an important area of investigation. In this study, we used fMRI to replicate previous findings, demonstrating an association between parental SES and PFC function during childhood. In addition, we present two hypothetical mechanisms by which SES could come to affect PFC function of this association: language environment and stress reactivity. We measured language use in the home environment and change in salivary cortisol before and after fMRI scanning. Complexity of family language, but not the child's own language use, was associated with both parental SES and PFC activation. Change in salivary cortisol was also associated with both SES and PFC activation. These observed associations emphasize the importance of both enrichment and adversity-reduction interventions in creating good developmental environments for all children. 相似文献