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31.
To enhance target production from biocatalysts, it is necessary to thoroughly understand the molecular mechanisms involved in production, degradation, and, importantly, adaptation to the required environment. One such bacterium with high potential for biocatalysis is the solvent-tolerant bacteria Pseudomonas putida S12, which, among others, is able to degrade organic solvents. For bioconversion of organic solvents to become a successful industrial process, the understanding of the molecular response upon solvent tolerance is essential. Here we performed a quantitative analysis of the P. putida S12 proteome at different stages of adaptation to toluene. Using a stable isotope dimethylation labeling approach we monitored the differential expression of 528 proteins, including often hard-to-detect membrane associate proteins, such as multiple RND-family transporters and ABC transporters of nutrients. Our quantitative proteomics approach revealed the remarkable ability of P. putida S12 to severely change its protein expression profile upon toluene exposure. This proteome response entails a significant increase in energy metabolism and expression of the solvent efflux pump SrpABC, confirming its role in solvent tolerance. Other proteins strongly up-regulated in the presence of toluene include the multidrug efflux membrane protein PP1272 and the cation/acetate symporter ActP and may form interesting alternative targets for improving solvent tolerance. 相似文献
32.
Koffler Christoph Amor Ben Carbajales-Dale Michael Cascio Joseph Conroy Alison Fava James A. Gaudreault Caroline Gloria Thomas Hensler Connie Horvath Arpad Humbert Sebastien Manzardo Alessandro Margni Manuele Osset Philippe Sinistore Julie Vigon Bruce Wallace Michele L Wang Michael Prox Martina 《The International Journal of Life Cycle Assessment》2020,25(3):478-482
The International Journal of Life Cycle Assessment - 相似文献
33.
Lakhdar Ghazouani Nesrine Abboud Sonia Ben Hadj Khalifa Claire Perret Viviane Nicaud Wassim Youssef Almawi François Cambien Touhami Mahjoub 《Molecular biology reports》2011,38(1):495-501
P-selectin (SELP) and its counter-receptor, P-selectin glycoprotein ligand-1 (PSGL-1), play key role in the transient attachment
of leukocytes to endothelial cells predisposing to coronary heart disease (CHD). In the current report, 293 angiographically
proven CHD patients and 327 age, gender, and race-matched controls were included. Our aim was to evaluate the contribution
to CHD of the following SNPs: C-2123G, G-1969A and T715P in SELP, Met62Ile and the VNTR variants in PSGL-1 gene in a North African population from Tunisia. While there were no significant differences in the distribution of SELP
or PSGL-1 alleles or genotypes between patients and controls, a trend for a significant association of the C-2123G genotypes
distribution with incident CHD was observed (P = 0.06). Assuming an additive model of transmission, the risk was 74% higher among subjects carrying the GG genotypes in
comparison to those carrying the CC genotype (OR = 1.74 [1.01–2.98], P = 0.04) and 80% higher in the recessive model (OR = 1.80 [1.08–3.01], P = 0.02). Haplotype analysis did not identify any specific SELP or PSGL-1 haplotypes to be associated with CHD. The present
study demonstrated no evidence of association between individual SELP or PSGL-1 SNPs or haplotypes with incident CHD. However,
this study replicates absence of association of the mostly studied SNP, T715P, previously reported in individuals with African
origin. 相似文献
34.
Ines Hammami Bassem Jaouadi Abir Ben Bacha Ahmed Rebai Samir Bejar Xavier Nesme Ali Rhouma 《Biotechnology and Bioprocess Engineering》2012,17(1):41-49
Bacillus subtilis strain 14B was used to produce a novel antimicrobial peptide (bacteriocin) called Bac 14B. Pure bacteriocin was obtained
after heat and acidic treatments (80°C and pH 4), precipitation by ammonium sulfate, and chromatography on Sephadex G-50 and
Mono Q Sepharose columns. Based on MALDI-TOF mass spectrometry analysis, purified Bac 14B is a monomer protein with a molecular
mass of 20110.13 Da. N-terminal sequencing allowed for the straightforward identification of its first 12 residues, which
were of a pure bacteriocin. It also revealed that this bacteriocin contained a unique sequence, namely M-L-K-A-N-L-Q-N-P-L-N-A,
suggesting the identification of a novel compound. Bac 14B was stable for 1 h at temperatures up to 80°C and pH of 4 ∼ 8.
It also proved sensitive to various proteases, which demonstrated its protein nature. Bac 14B displayed a bacteriolytical
mode of action and a broad range of inhibitory spectra toward Gram-positive and -negative pathogens. Interestingly, based
on conventional agronomic seed vigor parameters, the application of Bac 14B (500 activity units/mL) to various crops revealed
that this bacteriocin was a potent exogenous enhancer of growth that stimulated the seedling vigor of tomatoes and muskmelons.
Compared to those of the control, the germination percentage, shoot weight, shoot height, and root length were all significantly
enhanced in Bac 14B-treated plant seeds. Bac 14B also exhibited effective disinfectant properties against a wide range of
seedborne diseases and significant effects on the control of damping off diseases, particularly at the pregermination stage.
It also proved to be effective against root rot diseases caused by Alternaria solani and other bacterial seedborne pathogens such as wilt diseases. The findings indicate that Bac 14B is the first B. subtilis-produced bacteriocin ever reported to exhibit such promising biological properties. 相似文献
35.
Injection of tumor cells in mice more than 30 years ago resulted in the discovery of an epithelial antigen, later defined as a cell adhesion molecule (EpCAM). Although EpCAM has since evoked significant interest as a target in cancer therapy, mechanistic insights on the functions of this glycoprotein have been emerging only very recently. This may have been caused by the multitude of functions attributed to the glycoprotein, its localization at different subcellular sites and complex posttranslational modifications. Here, we review how EpCAM modifies cell–cell contact adhesion strength and tissue plasticity, and how it regulates cell proliferation and differentiation. Major knowledge derived from human diseases will be highlighted: Mutant EpCAM that is absent from the cell surface leads to fatal intestinal abnormalities (congenital tufting enteropathy). EpCAM-mediated cell proliferation in cancer may result from signaling (i) via regulated intramembrane proteolysis and/or (ii) the localization and association with binding partners in specialized membrane microdomains. New insight in EpCAM signaling will help to develop optimized cancer therapies and open new avenues in the field of regenerative medicine. 相似文献
36.
Marcelle Bens Sophie Vimont Sanae Ben Mkaddem Cécilia Chassin Jean‐Michel Goujon Viviane Balloy Michel Chignard Catherine Werts Alain Vandewalle 《Cellular microbiology》2014,16(10):1503-1517
Uropathogenic Escherichia coli (UPEC) colonizing kidneys is the main cause of acute pyelonephritis. TLR5 that senses flagellin was shown to be highly expressed in the bladder and to participate in host defence against flagellated UPEC, although its role in kidneys still remains elusive. Here we show that TLR5 is expressed in renal medullary collecting duct (MCD) cells, which represent a preferential site of UPEC adhesion. Flagellin, like lipopolysaccharide, stimulated the production of the chemoattractant chemokines CXCL1 and CXCL2, and subsequent migration capacity of neutrophils in cultured wild‐type (WT) and Tlr4?/? MCDs, but not in Tlr5?/? MCDs. UPEC can translocate across intact MCD layers without altering tight junctions. Strikingly, the invasion capacity and transcellular translocation of the UPEC strain HT7 were significantly lower in Tlr5?/? than in WT MCDs. The non‐motile HT7ΔfliC mutant lacking flagellin also exhibited much lower translocation capacities than the HT7 isolates. Finally, Tlr5?/? kidneys exhibited less infiltrating neutrophils than WT kidneys one day after the transurethral inoculation of HT7, and greater delayed renal bacterial loads in the day 4 post‐infected Tlr5?/? kidneys. Overall, these findings indicate that the epithelial TLR5 participates to renal antibacterial defence, but paradoxically favours the translocation of UPEC across intact MCD cell layers. 相似文献
37.
Abdolmajid Ghasemian Azam Fattahi Seyyed Khalil Shokouhi Mostafavi Ali Hussein Almarzoqi Mojtaba Memariani Olfa Ben Braiek Hadi M. Yassine Neda Sadat Shokouhi Mostafavi Mohanad Mohsin Ahmed Seyede Amene Mirforughi 《Journal of cellular physiology》2019,234(10):16847-16860
Helicobacter pylori (H. pylori) causes gastric mucosa inflammation and gastric cancer mostly via several virulence factors. Induction of proinflammatory pathways plays a crucial role in chronic inflammation, gastric carcinoma, and H. pylori pathogenesis. Herbal medicines (HMs) are nontoxic, inexpensive, and mostly anti-inflammatory reminding meticulous emphasis on the elimination of H. pylori and gastric cancer. Several HM has exerted paramount anti-H. pylori traits. In addition, they exert anti-inflammatory effects through several cellular circuits such as inhibition of 5′-adenosine monophosphate-activated protein kinase, nuclear factor-κB, and activator protein-1 pathway activation leading to the inhibition of proinflammatory cytokines (interleukin 1α [IL-1α], IL-1β, IL-6, IL-8, IL-12, interferon γ, and tumor necrosis factor-α) expression. Furthermore, they inhibit nitrous oxide release and COX-2 and iNOS activity. The apoptosis induction in Th1 and Th17-polarized lymphocytes and M2-macrophagic polarization and STAT6 activation has also been exhibited. Thus, their exact consumable amount has not been revealed, and clinical trials are needed to achieve optimal concentration and their pharmacokinetics. In the aspect of bioavailability, solubility, absorption, and metabolism of herbal compounds, nanocarriers such as poly lactideco-glycolide-based loading and related formulations are helpful. Noticeably, combined therapies accompanied by probiotics can also be examined for better clearance of gastric mucosa. In addition, downregulation of inflammatory microRNAs (miRNAs) by HMs and upregulation of those anti-inflammatory miRNAs is proposed to protect the gastric mucosa. Thus there is anticipation that in near future HM-based formulations and proper delivery systems are possibly applicable against gastric cancer or other ailments because of H. pylori. 相似文献
38.
Ben Raymond Denis J. Wright Neil Crickmore Michael B. Bonsall 《Proceedings. Biological sciences / The Royal Society》2013,280(1769)
Pesticide mixtures can reduce the rate at which insects evolve pesticide resistance. However, with live biopesticides such as the naturally abundant pathogen Bacillus thuringiensis (Bt), a range of additional biological considerations might affect the evolution of resistance. These can include ecological interactions in mixed infections, the different rates of transmission post-application and the impact of the native biodiversity on the frequency of mixed infections. Using multi-generation selection experiments, we tested how applications of single and mixed strains of Bt from diverse sources (natural isolates and biopesticides) affected the evolution of resistance in the diamondback moth, Plutella xylostella, to a focal strain. There was no significant difference in the rate of evolution of resistance between single and mixed-strain applications although the latter did result in lower insect populations. The relative survivorship of Bt-resistant genotypes was higher in the mixed-strain treatment, in part owing to elevated mortality of susceptible larvae in mixtures. Resistance evolved more quickly with treatments that contained natural isolates, and biological differences in transmission rate may have contributed to this. Our data indicate that the use of mixtures can have unexpected consequences on the fitness of resistant and susceptible insects. 相似文献
39.
The electrostatic force including the intramolecular Coulombic interactions and the electrostatic contribution of solvation effect were entirely calculated by using the finite difference Poisson-Boltzmann method (FDPB), which was incorporated into the GROMOS96 force field to complete a new finite difference stochastic dynamics procedure (FDSD). Simulations were performed on an insulin dimer. Different relative dielectric constants were successively assigned to the protein interior; a value of 17 was selected as optimal for our system. The simulation data were analyzed and compared with those obtained from 500-ps molecular dynamics (MD) simulation with explicit water and a 500-ps conventional stochastic dynamics (SD) simulation without the mean solvent force. The results indicate that the FDSD method with GROMOS96 force field is suitable to study the dynamics and structure of proteins in solution if used with the optimal protein dielectric constant. 相似文献
40.
Pathogen spread can cause population declines and even species extinctions. Nonetheless, in the absence of tailored monitoring schemes, documenting pathogen spread can be difficult. In the case of worldwide amphibian declines the best present understanding is that the chytrid fungus Batrachochytrium dendrobatidis (Bd) has recently spread, causing amphibian declines and extinction in the process. However, good evidence demonstrating pathogen arrival followed by amphibian decline is rare, and analysis of putative evidence is often inadequate. Here we attempt to examine the relationship between Bd arrival and amphibian decline across north-eastern Australia, using sites where a wave-like pattern of amphibian decline was first noticed and at which intensive research has since been conducted. We develop an analytical framework that allows rigorous estimation of pathogen arrival date, which can then be used to test for a correlation between the time of pathogen arrival and amphibian decline across sites. Our results show that, with the current dataset, the earliest possible arrival date of Bd in north-eastern Australia is completely unresolved; Bd could have arrived immediately before sampling commenced or may have arrived thousands of years earlier, the present data simply cannot say. The currently available data are thus insufficient to assess the link between timing of pathogen arrival and population decline in this part of the world. This data insufficiency is surprising given that there have been decades of research on chytridiomycosis in Australia and that there is a general belief that the link between Bd arrival and population decline is well resolved in this region. The lack of data on Bd arrival currently acts as a major impediment to determining the role of environmental factors in driving the global amphibian declines, and should be a major focus of future research. 相似文献