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91.
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
92.
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
93.
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
94.
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
95.
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
96.
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
97.
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
98.
Dervillez X Gottimukkala C Kabbara KW Nguyen C Badakhshan T Kim SM Nesburn AB Wechsler SL Benmohamed L 《Future virology》2012,7(4):371-378
Considering the limited success of the recent herpes clinical vaccine trial [1], new vaccine strategies are needed. Infections with herpes simplex virus type 1 and type 2 (HSV-1 & HSV-2) in the majority of men and women are usually asymptomatic and results in lifelong viral latency in neurons of sensory ganglia (SG). However, in a minority of men and women HSV spontaneous reactivation can cause recurrent disease (i.e., symptomatic individuals). Our recent findings show that T cells from symptomatic and asymptomatic men and women (i.e. those with and without recurrences, respectively) recognize different herpes epitopes. This finding breaks new ground and opens new doors to assess a new vaccine strategy: mucosal immunization with HSV-1 & HSV-2 epitopes that induce strong in vitro CD4 and CD8 T cell responses from PBMC derived from asymptomatic men and women (designated here as "asymptomatic" protective epitopes") could boost local and systemic "natural" protective immunity, induced by wild-type infection. Here we highlight the rationale and the future of our emerging "asymptomatic" T cell epitope-based mucosal vaccine strategy to decrease recurrent herpetic disease. 相似文献
99.
Six soil samples from natural and cultivated sites of Saudi Arabia were investigated for ciliate diversity, using the non-flooded Petri dish culture method, live observation, and silver impregnation. We identified 135 species, all new for the fauna of Saudi Arabia, of which seven were undescribed: Spathidium alqasabi nov. spec.; Enchelyodon alqasabi nov. spec.; Metauroleptus arabicus nov. gen., nov. spec.; Pseudohemisincirra arabica nov. gen., nov. spec.; Saudithrix terricola? Berger, Al-Rasheid and Foissner, 2006; Oxytricha arabica nov. spec.; and Erimophrya monostyla nov. spec. Based on Spathidium alqasabi, S. seppelti foissneri? Vd'a?ny et al., 2006 and S. seppelti etoschense? Foissner et al., 2002 are raised to species rank; for the latter, a new name is required to avoid homonymy: Spathidium fraterculum nov. nom. The new genus Metauroleptus, which possesses two long and two to three short ventral cirral rows, generates all dorsal kineties intrakinetally and produces caudal cirri exclusively in dorsal kinety 1. Metauroleptus belongs to the hypotrichs, while family classification remains doubtful. The same applies to the new hypotrich genus Pseudohemisincirra, which has frontoventral and transverse cirri, while buccal cirri and caudal cirri are absent. The number of species contained in Saudi Arabian soils, including sand dunes, is in the range reported from other regions of the earth, suggesting that ciliates are well adapted to dry habitats, possibly mainly by their ability to produce very resistant resting cysts, most surviving for a long time due to reduced metazoan predation. 相似文献
100.
Taïeb A Morice-Picard F Jouary T Ezzedine K Cario-André M Gauthier Y 《Pigment cell & melanoma research》2008,21(6):646-652
Clinical findings in vitiligo challenge the widely accepted organ specific autoimmune pathomechanisms. We draw the attention to the fact that the distribution of segmental vitiligo (SV) fits in at least a subset of patients a pattern usually associated with cutaneous mosaicism. The association of SV to non-segmental vitiligo (NSV) now confirmed by several observations indicates a continuum between the two subsets with shared predisposing genetic factors, including genes operating specifically in the skin. Some pedigrees associating SV and NSV further suggest a mechanism of loss of heterozygosity for a dominant gene controlling part of the cutaneous phenotype. The mosaic hypothesis applies only to SV and to the rare SV-NSV association, but suggests that predisposing genetic factors in common NSV should also be searched directly in the skin. SV would be a good candidate disease to explore as a proof of principle of a new gene discovery strategy useful for multigenic disorders with organ specificity, applicable in priority to chronic inflammatory skin disorders. 相似文献