Cadmium and arsenic-induced-stress differentially modulates Arabidopsis root architecture, peroxisome distribution, enzymatic activities and their nitric oxide content

In plant cells, cadmium (Cd) and arsenic (As) exert toxicity mainly by inducing oxidative stress through an imbalance between the production of reactive oxygen species (ROS) and reactive nitrogen species (RNS), and their detoxification. Nitric oxide (NO) is a RNS acting as signalling molecule coordinating plant development and stress responses, but also as oxidative stress inducer, depending on its cellular concentration. Peroxisomes are versatile organelles involved in plant metabolism and signalling, with a role in cellular redox balance thanks to their antioxidant enzymes, and their RNS (mainly NO) and ROS. This study analysed Cd or As effects on peroxisomes, and NO production and distribution in the root system, including primary root (PR) and lateral roots (LRs). Arabidopsis thaliana wild-type and transgenic plants enabling peroxisomes to be visualized in vivo, through the expression of the 35S-cyan fluorescent protein fused to the peroxisomal targeting signal1 (PTS1) were used. Peroxisomal enzymatic activities including the antioxidant catalase, the H2O2-generating glycolate oxidase, and the hydroxypyruvate reductase, and root system morphology were also evaluated under Cd/As exposure. Results showed that Cd and As differently modulate these activities, however, catalase activity was inhibited by both. Moreover, Arabidopsis root system was altered, with the pollutants differently affecting PR growth, but similarly enhancing LR formation. Only in the PR apex, and not in LR one, Cd more than As caused significant changes in peroxisome distribution, size, and in peroxisomal NO content. By contrast, neither pollutant caused significant changes in peroxisomes size and peroxisomal NO content in the LR apex

Crowdsourcing the corpasome

The suffix -ome conveys “comprehensiveness” in some way. The idea of the Corpasome started half-jokingly, acknowledging the efforts to sequence five members of my family. After the unexpected response from many scientists from around the world, it has become clear how useful this approach could be for understanding the genomic information contained in our personal genomics tests

Current overview of S-nitrosoglutathione (GSNO) in higher plants

S-nitrosoglutathione is a nitric oxide-derived molecule, generated by the interaction of nitric oxide (NO) with reduced glutathione (GSH) in a process called S-nitrosylation (Figure 1). The reaction appears to take place either through the formation of N2O3 or the addition of NO to a glutathionyl radical formed during this reaction (Broniowska et al., 2013). GSNO is regarded as an intracellular NO reservoir as well as a vehicle of NO throughout the cell, which enables NO biological activity to expand. GSNO is also considered to be the most abundant low-molecular-mass (LMM) S-nitrosothiol (SNO). This family includes other molecules such as S-nitrosocysteine (CySNO) and S-nitrosocysteinylglycine (GlyCySNO), which have been the subject of less study in the field of plant research. There is another group of SNOs called high-molecular mass (HMM) SNOs which are produced by NO binding to sulfhydryl (-SH) groups present in specific cysteine residues of proteins. Figure 1 shows a simple model of GSNO metabolism and its interactions with other molecules in cells where different reactions including S-nitrosylation, S-transnitrosation, and S-glutathionylation are involved (Hogg, 2002; Martínez-Ruiz and Lamas, 2007). In plants, research has focused on the importance of total SNOs in specific stress situations (Feechan et al., 2005; Chaki et al., 2011a) and on the identification of the potential protein targets of S-nitrosylation as this kind of post-translational modification can alter the function of the affected proteins (Astier et al., 2012). Initial studies in this area exogenously applied GSNO in order to identify the pool of potential protein candidates (Lindermayr et al., 2005). However, less attention has been paid to the abundance, distribution, and modulation of endogenous GSNO under natural and stress conditions. In this article, we will provide a current overview of GSNO in higher plants. [EN]Work in our laboratories is supported by ERDF-cofinanced grants from the Ministry of Science and Innovation (BIO2012-33904 and BFU2011-22779)Peer reviewe

Las transformaciones sociales y físicas por suburbanización: el caso de Rincón de la Victoria (Málaga)

The present report tries to explain the processes of change induced from a central city, in this case, the object of this study is Málaga Urban Agglomeration, that admits in its bossom an amalgam of municipalities from different fields. Inside the urban agglomeration, we really can distinguish the coast area, with a stage of integration in the urban dynamics, in contrast to the valley area and the Málaga mountains. On the Oriental Coast, we have selected the municipality of Rincón de la Victoria, because of the fact that it's a town that suffers from great changes due to a social group of urban procedence, eminently young and of middle qualification. These changes are what we'll try to explain.El artículo que exponemos a continuación trata de describir los procesos de transformación físico y social que son inducidos desde un núcleo central, en este caso, el área objeto de estudio es la aglomeración urbana de Málaga, que acoge en su seno a una amalgama de municipios de diferentes ámbitos. En efecto, dentro de la aglomeración, podemos distinguir el entorno del litoral, con un mayor grado de integración en la dinámica urbana, en contraposición con el entorno del Valle y los Montes. En la costa oriental hemos seleccionado el municipio de Rincón de la Victoria, por ser un municipio que padece una intensa urbanización inducida desde la capital provincial y que se concreta con una serie de transformaciones físicas y sociales que trataremos de esbozar

Editorial:Subcellular compartmentalization of plant antioxidants and ROS generating systems, volume II

JP, MR-R and FC were financed by ERDF-co-financed grants from the Junta de Andalucía (P18-FR-1359) and the Ministry of Science and Innovation (PID2019-103924GB-I00), Spain. CF was financed by BBSRC/GCRF Grant (BB/T008865/1), UK

NADP-Dependent Isocitrate Dehydrogenase from Arabidopsis Roots Contributes in the Mechanism of Defence against the Nitro-Oxidative Stress Induced by Salinity

NADPH regeneration appears to be essential in the mechanism of plant defence against oxidative stress. Plants contain several NADPH-generating dehydrogenases including isocitrate dehydrogenase (NADP-ICDH), glucose-6-phosphate dehydrogenase (G6PDH), 6-phosphogluconate dehydrogenase (6PGDH), and malic enzyme (ME). In Arabidopsis seedlings grown under salinity conditions (100 mM NaCl) the analysis of physiological parameters, antioxidant enzymes (catalase and superoxide dismutase) and content of superoxide radical (O2  ∙−), nitric oxide (NO), and peroxynitrite (ONOO−) indicates a process of nitro-oxidative stress induced by NaCl. Among the analysed NADPH-generating dehydrogenases under salinity conditions, the NADP-ICDH showed the maximum activity mainly attributable to the root NADP-ICDH. Thus, these data provide new insights on the relevance of the NADP-ICDH which could be considered as a second barrier in the mechanism of response against the nitro-oxidative stress generated by salinity

Differential molecular response of monodehydroascorbate reductase and glutathione reductase by nitration and S-nitrosylation

The ascorbate–glutathione cycle is a metabolic pathway that detoxifies hydrogen peroxide and involves enzymatic and non-enzymatic antioxidants. Proteomic studies have shown that some enzymes in this cycle such as ascorbate peroxidase (APX), monodehydroascorbate reductase (MDAR), and glutathione reductase (GR) are potential targets for post-translational modifications (PMTs) mediated by nitric oxide-derived molecules. Using purified recombinant pea peroxisomal MDAR and cytosolic and chloroplastic GR enzymes produced in Escherichia coli, the effects of peroxynitrite (ONOO–) and S-nitrosoglutathione (GSNO) which are known to mediate protein nitration and S-nitrosylation processes, respectively, were analysed. Although ONOO– and GSNO inhibit peroxisomal MDAR activity, chloroplastic and cytosolic GR were not affected by these molecules. Mass spectrometric analysis of the nitrated MDAR revealed that Tyr213, Try292, and Tyr345 were exclusively nitrated to 3-nitrotyrosine by ONOO–. The location of these residues in the structure of pea peroxisomal MDAR reveals that Tyr345 is found at 3.3 Å of His313 which is involved in the NADPbinding site. Site-directed mutagenesis confirmed Tyr345 as the primary site of nitration responsible for the inhibition of MDAR activity by ONOO–. These results provide new insights into the molecular regulation of MDAR which is deactivated by nitration and S-nitrosylation. However, GR was not affected by ONOO– or GSNO, suggesting the existence of a mechanism to conserve redox status by maintaining the level of reduced GSH. Under a nitro-oxidative stress induced by salinity (150 mM NaCl), MDAR expression (mRNA, protein, and enzyme activity levels) was increased, probably to compensate the inhibitory effects of S-nitrosylation and nitration on the enzyme. The present data show the modulation of the antioxidative response of key enzymes in the ascorbate–glutathione cycle by nitric oxide (NO)- PTMs, thus indicating the close involvement of NO and reactive oxygen species metabolism in antioxidant defence against nitro-oxidative stress situations in plants.Spanish GovernmentERDF - Ministry of Economy and Competitiveness BIO2012-33904Junta de Andalucía BIO286 BIO19

Antioxidant Profile of Pepper (Capsicum annuum L.) Fruits Containing Diverse Levels of Capsaicinoids

Capsicum is the genus where a number of species and varieties have pungent features due to the exclusive content of capsaicinoids such as capsaicin and dihydrocapsaicin. In this work, the main enzymatic and non-enzymatic systems in pepper fruits from four varieties with different pungent capacity have been investigated at two ripening stages. Thus, a sweet pepper variety (Melchor) from California-type fruits and three autochthonous Spanish varieties which have different pungency levels were used, including Piquillo, Padrón and Alegría riojana. The capsaicinoids contents were determined in the pericarp and placenta from fruits, showing that these phenyl-propanoids were mainly localized in placenta. The activity profiles of catalase, total and isoenzymatic superoxide dismutase (SOD), the enzymes of the ascorbate–glutathione cycle (AGC) and four NADP-dehydrogenases indicate that some interaction with capsaicinoid metabolism seems to occur. Among the results obtained on enzymatic antioxidants, the role of Fe-SOD and the glutathione reductase from the AGC is highlighted. Additionally, it was found that ascorbate and glutathione contents were higher in those pepper fruits which displayed the greater contents of capsaicinoids. Taken together, all these data indicate that antioxidants may contribute to preserve capsaicinoids metabolism to maintain their functionality in a framework where NADPH is perhaps playing an essential role

A review on additive manufacturing and materials for catalytic applications: Milestones, key concepts, advances and perspectives

Catalysis, a driving force of the chemical industry is increasingly being influenced by additive manufacturing. The link between them is based on the need to intensify catalytic processes in order to make them more efficient and sustainable. Additive manufacturing can satisfy such a need, generating devices with an advanced design, easy production, and great adaptation, in addition to their catalytic functionality. The exponential growth of examples reported on the application of 3D-printing in catalysis has led to the need to compile and analyse these cases and thus establish, through this review, the most in-depth analysis done to date. The manuscript includes a brief background of the history of additive manufacturing and the classification of the different printing techniques. Subsequently, it identifies the intensification of processes, among other aspects, as the key for understanding the union of additive manufacturing and catalysis. Then, it explores in detail how such a combination occurs, establishing the most comprehensive classification to date between the two large groups of printable devices with catalytic properties. Finally, a series of perspectives are proposed in which the most probable courses of new advances in this field of research are identified.O.H. Laguna agradece a la Universidad de Jaén por el apoyo el contrato postdoctoral a través de la ‘‘Acción 6 del Plan de Apoyo a la Investigación de la Universidad de Jaén (2017-2019).