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71.
Guillermo Rodríguez‐Hernández Inés González‐Herrero Carolin Walter Sara González de Tena‐Dávila Salma Parvin Oskar Haas Wilhelm Woessmann Martin Stanulla Martin Schrappe Martin Dugas Yasodha Natkunam Alberto Orfao Verónica Domínguez Belén Pintado Oscar Blanco Diego Alonso‐López Javier De Las Rivas Alberto Martín‐Lorenzo Rafael Jiménez Francisco Javier García Criado María Begoña García Cenador Izidore S Lossos Carolina Vicente‐Dueñas Arndt Borkhardt Julia Hauer Isidro Sánchez‐García 《The EMBO journal》2018,37(14)
72.
Belén Márquez‐García Gloria Comadira Nieves Fernandez‐Garcia Enrique Olmos Daniel Schnaubelt Karl J. Kunert Christine H. Foyer 《Plant biotechnology journal》2014,12(7):903-913
Ectopic cystatin expression has long been used in plant pest management, but the cysteine protease, targets of these inhibitors, might also have important functions in the control of plant lifespan and stress tolerance that remain poorly characterized. We therefore characterized the effects of expression of the rice cystatin, oryzacystatin‐I (OCI), on the growth, development and stress tolerance of crop (soybean) and model (Arabidopsis thaliana) plants. Ectopic OCI expression in soybean enhanced shoot branching and leaf chlorophyll accumulation at later stages of vegetative development and enhanced seed protein contents and decreased the abundance of mRNAs encoding strigolactone synthesis enzymes. The OCI‐expressing A. thaliana showed a slow‐growth phenotype, with increased leaf numbers and enhanced shoot branching at flowering. The OCI‐dependent inhibition of cysteine proteases enhanced drought tolerance in soybean and A. thaliana, photosynthetic CO2 assimilation being much less sensitive to drought‐induced inhibition in the OCI‐expressing soybean lines. Ectopic OCI expression or treatment with the cysteine protease inhibitor E64 increased lateral root densities in A. thaliana. E64 treatment also increased lateral root densities in the max2‐1 mutants that are defective in strigolactone signalling, but not in the max3‐9 mutants that are defective in strigolactone synthesis. Taken together, these data provide evidence that OCI‐inhibited cysteine proteases participate in the control of growth and stress tolerance through effects on strigolactones. We conclude that cysteine proteases are important targets for manipulation of plant growth, development and stress tolerance, and also seed quality traits. 相似文献
73.
Identification of a novel galactosyl transferase involved in biosynthesis of the mycobacterial cell wall
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Mikusová K Belánová M Korduláková J Honda K McNeil MR Mahapatra S Crick DC Brennan PJ 《Journal of bacteriology》2006,188(18):6592-6598
The possibility of the Rv3782 protein of Mycobacterium tuberculosis being a putative galactosyl transferase (GalTr) implicated in galactan synthesis arose from its similarity to the known GalTr Rv3808c, its classification as a nucleotide sugar-requiring inverting glycosyltransferase (GT-2 family), and its location within the "possible arabinogalactan biosynthetic gene cluster" of M. tuberculosis. In order to study the function of the enzyme, active membrane and cell wall fractions from Mycobacterium smegmatis containing the overexpressed Rv3782 protein were incubated with endogenous decaprenyldiphosphoryl-N-acetylglucosaminyl-rhamnose (C(50)-P-P-GlcNAc-Rha) as the primary substrate for galactan synthesis and UDP-[(14)C]galactopyranose as the immediate precursor of UDP-[(14)C]galactofuranose, the ultimate source of all of the galactofuranose (Galf) units of galactan. Obvious increased and selective synthesis of C(50)-P-P-GlcNAc-Rha-Galf-Galf, the earliest product in the pathway leading to the fully polymerized galactan, was observed, suggesting that Rv3782 encodes a GalTr involved in the first stages of galactan synthesis. Time course experiments pointed to a possible bifunctional enzyme responsible for the initial synthesis of C(50)-P-P-GlcNAc-Rha-Galf, followed by immediate conversion to C(50)-P-P-GlcNAc-Rha-Galf-Galf. Thus, Rv3782 appears to be the initiator of galactan synthesis, while Rv3808c continues with the subsequent polymerization events. 相似文献
74.
María Ángeles Martín Ana Belén Granado Serrano Sonia Ramos María Izquierdo Pulido Laura Bravo Luis Goya 《The Journal of nutritional biochemistry》2010,21(3):196-205
Oxidative stress is widely recognized as an important mediator of apoptosis in liver cells and plays a pivotal role in the pathogenesis of several diseases. Cocoa flavonoids have shown a powerful antioxidant activity providing protection against oxidation and helping prevent oxidative stress-related diseases. However, the molecular mechanisms responsible for this protection are not fully understood. Thus, in this study we investigated the protective effect of a cocoa polyphenolic extract (CPE) against tert-butyl hydroperoxide (t-BOOH)-induced apoptosis and the molecular mechanisms involved in this process. Incubation of HepG2 cells with t-BOOH induced apoptosis as evidenced by caspase-3 activation. This effect was accompanied by increased reactive oxygen species formation and by transient activation of the extracellular regulated kinases (ERKs) as well as sustained activation of the c-Jun N-terminal kinases (JNKs). On the contrary, pretreatment of HepG2 cells with CPE prevented apoptosis through the reduction of reactive oxygen species generation and the modulation of the apoptotic pathways activated by t-BOOH. CPE treatment also activated survival signaling proteins, such as protein kinase B (AKT) and ERKs, and increased the activities of two antioxidant enzymes, glutathione peroxidase (GPx) and glutathione reductase (GR). ERK's implication on GPx and GR induction and the protective effect of CPE against t-BOOH-induced oxidative stress and apoptosis were confirmed through experiments with selective inhibitors. These findings suggest that CPE is an effective inductor of GPx and GR activities via ERK activation and that this up-regulation seems to be required to attenuate t-BOOH-induced injury. 相似文献
75.
From the water column of Lake Baikal, several strains of prosthecate bacteria belonging to the genera Caulobacter and Brevundimonas were isolated. In this article, the methods applied for their isolation and cell number determination are described; the occurrence frequency and spatial distribution of these microorganisms in the lake are demonstrated. Characterization of the species composition of cultivable and uncultivable prosthecate bacteria was carried out using the methods of traditional and molecular microbiology, respectively. A comparative phylogenetic analysis of the DNA sequences of uncultivable bacteria, which showed homology to the members of the alpha subclass of proteobacteria, was carried out. It was demonstrated that the lake water column is inhabited by uncultivable alpha-proteobacteria of uncertain phylogenetic affinity, in addition to representatives of the species Caulobacter vibrioides and C. leidyi, which were detected by traditional microbiological methods. 相似文献
76.
Vizcaíno JA Redondo J Suárez MB Cardoza RE Hermosa R González FJ Rey M Monte E 《Applied microbiology and biotechnology》2007,75(4):853-862
The functional genomics project “TrichoEST” was developed focused on different taxonomic groups of Trichoderma with biocontrol potential. Four cDNA libraries were constructed, using similar growth conditions, from four different Trichoderma strains: Trichoderma longibrachiatum T52, Trichoderma asperellum T53, Trichoderma virens T59, and Trichoderma sp. T78. In this study, we present the analysis of the 8,160 expressed sequence tags (ESTs) generated. Each EST library was
independently assembled and 1,000–1,300 unique sequences were identified in each strain. First, we queried our collection
of ESTs against the NCBI nonredundant database using the BLASTX algorithm. Moreover, using the Gene Ontology hierarchy, we
performed the annotation of 40.9% of the unique sequences. Later, based on the EST abundance, we examined the highly expressed
genes in the four strains. A hydrophobin was found as the gene expressed at the highest level in two of the strains, but we
also found that other unique sequences similar to the HEX1, QID3, and NMT1 proteins were highly represented in at least two
of the Trichoderma strains.
Electronic supplementary material The online version of this article (doi:) contains supplementary material, which is available to authorized users. 相似文献
77.
78.
Optimisation of biocide dose as a function of residual biocide in a heat exchanger pilot plant effluent 总被引:1,自引:0,他引:1
Biofouling is one of the most serious problems facing numerous industrial processes. In the case of a heat exchanger unit, biological deposits adhering to the inside surface of its tubes reduce heat transfer and, thus, the thermal performance of the cycle. Control of this phenomenon is proving fundamental for both land and marine equipment to operate in optimum working conditions. Hence, it is necessary to apply antifouling methods capable of keeping surfaces free of any kind of biofouling. This paper reports on the behaviour resulting from use of the flow inversion method vs that obtained by using various chemical treatments. The study compares the effectiveness of certain chemical treatments (Na hypochlorite, peracetic acid and a compound formed by Na bromide + Na hypochlorite) for removing a biofouling film that has already formed on the inside surfaces of tubes in a heat exchanger pilot plant. The paper also addresses the issue of optimising the concentration of biocide dose as a function of the residual biocide in order minimise the environmental impact caused by effluent from industrial plants. The results indicate that it is possible to eliminate a biofilm formed on the inside surfaces of tubes by the use of intermittent doses of chemical treatments at low concentrations and over long application times. Furthermore, once the stabilisation phase is reached 6 d after starting the treatment, it is possible to maintain the conditions achieved using only 20% of the initial dosage. 相似文献
79.
80.
Truchet Daniela M. Noceti Belén M. Villagran Diana M. Truchet Rocío M. 《Human ecology: an interdisciplinary journal》2022,50(2):209-225
Human Ecology - We studied conservation paradigms of small-scale artisanal fishers and other actors involved in the conservation of the Bahía Blanca Estuary (BBE)—a Southwestern Atlantic... 相似文献