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31.
Proteomic Profiling of Recombinant Escherichia coli in High-Cell- Density Fermentations for Improved Production of an Antibody Fragment Biopharmaceutical 下载免费PDF全文
Ilana S. Aldor Denise C. Krawitz William Forrest Christina Chen Julie C. Nishihara John C. Joly Kathleen M. Champion 《Applied microbiology》2005,71(4):1717-1728
By using two-dimensional polyacrylamide gel electrophoresis, a proteomic analysis over time was conducted with high-cell-density, industrial, phosphate-limited Escherichia coli fermentations at the 10-liter scale. During production, a recombinant, humanized antibody fragment was secreted and assembled in a soluble form in the periplasm. E. coli protein changes associated with culture conditions were distinguished from protein changes associated with heterologous protein expression. Protein spots were monitored quantitatively and qualitatively. Differentially expressed proteins were quantitatively assessed by using a t-test method with a 1% false discovery rate as a significance criterion. As determined by this criterion, 81 protein spots changed significantly between 14 and 72 h (final time) of the control fermentations (vector only). Qualitative (on-off) comparisons indicated that 20 more protein spots were present only at 14 or 72 h in the control fermentations. These changes reflected physiological responses to the culture conditions. In control and production fermentations at 72 h, 25 protein spots were significantly differentially expressed. In addition, 19 protein spots were present only in control or production fermentations at this time. The quantitative and qualitative changes were attributable to overexpression of recombinant protein. The physiological changes observed during the fermentations included the up-regulation of phosphate starvation proteins and the down-regulation of ribosomal proteins and nucleotide biosynthesis proteins. Synthesis of the stress protein phage shock protein A (PspA) was strongly correlated with synthesis of a recombinant product. This suggested that manipulation of PspA levels might improve the soluble recombinant protein yield in the periplasm for this bioprocess. Indeed, controlled coexpression of PspA during production led to a moderate, but statistically significant, improvement in the yield. 相似文献
32.
L. Joly 《Insectes Sociaux》1958,5(4):373-378
Conclusion on aurait pu s'attendre à ce que les adultoïdes (stades Vbis) se groupent sur la même droite que les stades V normaux et les adultes prématurés (V) sur celle des imagos (fig. 6). On voit qu'il n'en est rien et que cela tient à ce que la croissance des organes du vol à la fin du développement larvaire deLocusta migratoria n'est pas représentée par une droite d'allométrie unique, mais présente une discontinuité à chacune des dernières mues, de sorte que les adultoïdes ne sont pas des stades V géants mais un stade supplémentaire ajouté au développement normal, et les imagos prématurés ne sont pas des adultes nains mais des adultes privés d'une partie de leur évolution larvaire. 相似文献
33.
Jean-François Fournier Yushma Bhurruth-Alcor Branislav Musicki Jérome Aubert Michèle Aurelly Claire Bouix-Peter Karinne Bouquet Laurent Chantalat Marion Delorme Bénédicte Drean Gwenaelle Duvert Nicolas Fleury-Bregeot Blanche Gauthier Karine Grisendi Craig S. Harris Laurent F. Hennequin Tatiana Isabet Florence Joly Loïc Tomas 《Bioorganic & medicinal chemistry letters》2018,28(17):2985-2992
A series of squaramide-based hydroxamic acids were designed, synthesized and evaluated against human HDAC enzyme. Squaramides were found to be potent in the Hut78 cell line, but initially suffered from low solubility. Leads with improved solubility and metabolic profiles were shown to be class I, IIB and IV selective. 相似文献
34.
Adrien Flahault Denis Trystram Marie Fouchard Bertrand Knebelmann Fran?ois Nataf Dominique Joly 《PloS one》2016,11(4)
BackgroundDespite a high prevalence of intracranial aneurysm (ICA) in autosomal dominant polycystic kidney disease (ADPKD), rupture events are rare. The current recommendations for ICA screening are based on expert opinions and studies with low levels of evidence.ObjectivesThe aim of our study was to describe the attitudes of practicing nephrologists in Europe towards screening for ICA using magnetic resonance angiography (MRA).MethodsWe conducted a web-based survey among 1315 European French-speaking nephrologists and nephrology residents. An anonymous, electronic questionnaire including 24 independent questions related to ICA screening modalities, indications and participant profiles was sent by email between September and December 2014. Four hundred and twenty nephrologists (mostly from France) participated, including 31 nephrology residents; the response rate was 32%.ResultsSystematic screening for ICA was advocated by 28% of the nephrologists. A family history of ICA rupture, sudden death, stroke and migraine were consensual indications for screening (> 90% of the panel). In other clinical situations largely not covered by the recommendations (pregnancy, nephrectomy, kidney transplantation, cardiac or hepatic surgery, uncontrolled hypertension, lack of familial ADPKD history, at-risk activity, tobacco use), the attitudes towards screening were highly divergent. ICA screening was influenced by nephrologists experience with ADPKD and by their practice setting. The majority of participants (57%) would not repeat a normal ICA screening. Only a few participants (22%) knew that non-contrast MRA was the reference diagnostic tool for ICA screening, whereas most participants thought that contrast enhancement was necessary to screen for ICA. The results from the nephrology residents were analyzed separately and yielded similar results.ConclusionThis practice survey revealed that most nephrologists follow the current recommendations for the initial screening of ICAs. However, more than a quarter of the panel was in favor of systematic ICA screening, most nephrologists did not know that contrast medium was not necessary to screen for ICA using MRA, and many areas of uncertainty remain. 相似文献
35.
Competitive exclusion of diarrheagenic Escherichia coli (ETEC) from human enterocyte-like Caco-2 cells by heat-killed Lactobacillus 总被引:7,自引:0,他引:7
Gilles Chauvière Marie-Hélène Coconnier Sophie Kerneis Arlette Darfeuille-Michaud Bernard Joly Alain L. Servin 《FEMS microbiology letters》1992,91(3):213-217
Diarrheagenic Escherichia coli (ETEC) bearing CFA/I or CFA/II adhesive factors specifically adhere onto the brush border of the polarized epithelial human intestinal Caco-2 cells in culture. Heat-killed Lactobacillus acidophilus strain LB, that adheres onto Caco-2 cells, inhibits diarrheagenic Escherichia coli adhesion in a concentration-dependent manner. Since the L. acidophilus does not express ETEC-CFA adhesive factors, it can be postulated that the heat-killed L. acidophilus LB cells inhibit diarrheagenic E. coli attachment by steric hindrance of the human enterocytic ETEC receptors. 相似文献
36.
L. Benoit A. Espíndola H. I Joly S. Neuenschwander N. Arrigo 《Molecular ecology》2013,22(4):1092-1104
Genetic diversity of contemporary domesticated species is shaped by both natural and human‐driven processes. However, until now, little is known about how domestication has imprinted the variation of fruit tree species. In this study, we reconstruct the recent evolutionary history of the domesticated almond tree, Prunus dulcis, around the Mediterranean basin, using a combination of nuclear and chloroplast microsatellites [i.e. simple sequence repeat (SSRs)] to investigate patterns of genetic diversity. Whereas conservative chloroplast SSRs show a widespread haplotype and rare locally distributed variants, nuclear SSRs show a pattern of isolation by distance with clines of diversity from the East to the West of the Mediterranean basin, while Bayesian genetic clustering reveals a substantial longitudinal genetic structure. Both kinds of markers thus support a single domestication event, in the eastern side of the Mediterranean basin. In addition, model‐based estimation of the timing of genetic divergence among those clusters is estimated sometime during the Holocene, a result that is compatible with human‐mediated dispersal of almond tree out of its centre of origin. Still, the detection of region‐specific alleles suggests that gene flow from relictual wild preglacial populations (in North Africa) or from wild counterparts (in the Near East) could account for a fraction of the diversity observed. 相似文献
37.
报道了7个楼梯草属和赤车属植物(荨麻科)新纪录,它们分别为锐齿楼梯草(E. cyrtandrifolium),变黄楼梯草(E. xanthophyllum),对叶楼梯草(E. sinense),宽叶楼梯草(E. platyphyllum),托叶楼梯草(E. nasutum),短叶赤车(P. brevifolia)和华南赤车(P. grijsii)。列出了各个物种的标本引证和地理分布情况。 相似文献
38.
Galvez T Parmentier ML Joly C Malitschek B Kaupmann K Kuhn R Bittiger H Froestl W Bettler B Pin JP 《The Journal of biological chemistry》1999,274(19):13362-13369
The gamma-aminobutyric acid type B (GABAB) receptor is distantly related to the metabotropic glutamate receptor-like family of G-protein-coupled receptors (family 3). Sequence comparison revealed that, like metabotropic glutamate receptors, the extracellular domain of the two GABAB receptor splice variants possesses an identical region homologous to the bacterial periplasmic leucine-binding protein (LBP), but lacks the cysteine-rich region common to all other family 3 receptors. A three-dimensional model of the LBP-like domain of the GABAB receptor was constructed based on the known structure of LBP. This model predicts that four of the five cysteine residues found in this GABAB receptor domain are important for its correct folding. This conclusion is supported by analysis of mutations of these Cys residues and a decrease in the thermostability of the binding site after dithiothreitol treatment. Additionally, Ser-246 was found to be critical for CGP64213 binding. Interestingly, this residue aligns with Ser-79 of LBP, which forms a hydrogen bond with the ligand. The mutation of Ser-269 was found to differently affect the affinity of various ligands, indicating that this residue is involved in the selectivity of recognition of GABAB receptor ligands. Finally, the mutation of two residues, Ser-247 and Gln-312, was found to increase the affinity for agonists and to decrease the affinity for antagonists. Such an effect of point mutations can be explained by the Venus flytrap model for receptor activation. This model proposes that the initial step in the activation of the receptor by agonist results from the closure of the two lobes of the binding domain. 相似文献
39.
40.
Salt cress. A halophyte and cryophyte Arabidopsis relative model system and its applicability to molecular genetic analyses of growth and development of extremophiles 总被引:16,自引:0,他引:16 下载免费PDF全文