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Low temperatures (0–10 °C) represent a major physiological stress for plants, negatively affecting both their growth rates and overall growth. Cold stress may induce a wide range of negative physiological effects, from oxidative stress to photosynthetic damage. We investigated the effects of low temperatures in two different model plants, Arabidopsis thaliana and Hordeum vulgare. We tested whether the oxidative pentose phosphate pathway (OPPP) is involved in the increase of reductants’ levels needed to counteract oxidative stress induced by cold. The expression, occurrence, and activity of different glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49) isoforms during cold stress and plant recovery from low temperatures, were measured at different growth stages from early germinated to mature pot-grown plants. Our results showed plants exhibited changes in different stress markers; ascorbate peroxidase – APX, catalase - CAT, proline, malondialdehyde, H2O2, NADPH/NADP+. We found that a major role in cold acclimation for cytosolic- and peroxisome-located G6PDHs, and different roles for plastidial/chloroplastic isoforms. This suggests that G6PDH isoforms may regulate redox homeostasis in low temperatures, in order to support the increased and continued demand of reductants during both cold stress and recovery stages. Furthermore, we found a significant involvement of (6PGDH), strengthening the idea that the contribution of the whole oxidative pentose phosphate pathway (OPPP) is required to sustain reductant supply under cold stress.

Capnophilic lactic fermentation (CLF) is an anaplerotic pathway exclusively identified in the anaerobic hyperthermophilic bacterium

V.P. Acknowledges Erasmus traineeship program by the University of Naples "Federico II". Funding for open access charge: Universidad de Granada / CBUA., An adequate availability of Zinc (Zn) is crucial for plant growth and development given the essentiality of this element. Thus, both Zn deficiency and Zn toxicity can limit crop yields. In plants, the responses to Zn imbalances involve important physiological aspects such as reactive oxygen species (ROS) accumulation, phytohormone balance, tricarboxylic acid cycle (TCA) metabolism, and organic acids (OAs) accumulation. However, a way to improve tolerance to stresses such as those produced by nutritional imbalances is the application of beneficial elements such as silicon (Si). In this study, we grew barley plants in hydroponics under Zn deficiency and toxicity conditions, applying Si in the form of CaSiO3 in order to assess its effectiveness against Zn imbalances. Parameters related to plant growth, oxidative stress, TCA enzyme activities, phytohormones and OAs accumulation were analyzed. Both Zn deficiency and toxicity reduced leaf biomass, increased ROS accumulation, and affected phytohormone and OAs concentrations and TCA enzyme activities. CaSiO3 treatment was effective in counteracting these effects enhancing Zn accumulation under Zn deficient conditions and limiting its accumulation under toxic conditions. In addition, this treatment decreased ROS levels, and improved ascorbate/glutathione and phytohormonal responses, citrate synthase activity, and malate/oxalate ratio. Therefore, this study enhanced the notion of the efficacy of CaSiO3 in improving tolerance to Zn imbalances., Universidad de Granada / CBUA

Capnophilic lactic fermentation (CLF) is an anaplerotic pathway exclusively identified in the anaerobic hyperthermophilic bacterium Thermotoga neapolitana, a member of the order Thermotogales. The CO2-activated pathway enables non-competitive synthesis of hydrogen and L-lactic acid at high yields, making it an economically attractive process for bioenergy production. In this work, we discovered and characterized CLF in Thermotoga sp. strain RQ7, a naturally competent strain, opening a new avenue for molecular investigation of the pathway. Evaluation of the fermentation products and expression analyses of key CLF-genes by RT-PCR revealed similar CLF-phenotypes between T. neapolitana and T. sp. strain RQ7, which were absent in the non-CLF-performing strain T. maritima. Key CLF enzymes, such as PFOR, HYD, LDH, RNF, and NFN, are up-regulated in the two CLF strains. Another important finding is the up-regulation of V-ATPase, which couples ATP hydrolysis to proton transport across the membranes, in the two CLF-performing strains. The fact that V-ATPase is absent in T. maritima suggested that this enzyme plays a key role in maintaining the necessary proton gradient to support high demand of reducing equivalents for simultaneous hydrogen and lactic acid synthesis in CLF.

In this study, the efficacy of Acca sellowiana fruit acetonic extract on human MDR cancer cells was tested for the first time, and it was demonstrated that the fruit extract is effective on both sensitive and resistant tumor cells. The effects of A. sellowiana extract on bacterial biofilm were also examined for the first time. By crystal violet assays and confocal microscopy analyses, it was demonstrated that the plant extract is able to strongly inhibit biofilm formation of both sensitive and resistant bacterial strains. Furthermore, antimicrobial activity assays and TEM analyses clearly demonstrated the effectiveness of plant extract on planktonic bacterial cells in both sensitive and resistant strains. Altogether, these findings intriguingly expand the panel of activities of A. sellowiana fruit extract with respect to previous reports, and open interesting perspectives to its therapeutic applications.

Algal species still show unrevealed and unexplored potentiality for the identification of new compounds. Photosynthetic organisms represent a valuable resource to exploit and sustain the urgent need of sustainable and green technologies. Particularly, unconventional organisms from extreme environments could hide properties to be employed in a wide range of biotechnology applications, due to their peculiar alleles, proteins, and molecules. In this review we report a detailed dissection about the latest and advanced applications of protein derived from algae. Furthermore, the innovative use of modified algae as bio-reactors to generate proteins or bioactive compounds was discussed. The latest progress about pharmaceutical applications, including the possibility to obtain drugs to counteract virus (as SARS-CoV-2) were also examined. The last paragraph will survey recent cases of the utilization of extremophiles as bio-factories for specific protein and molecule production.

This work was supported by the PAI programme (Plan Andaluz de Investigacion, Grupo de Investigacion AGR282). V. P. Acknowledges Erasmus traineeship program by the University of Naples "Federico II". The results presented in this paper are based on the PhD Thesis by Paradisone ( 2018)., Zinc (Zn) deficiency causes serious issues to plant growth and development, negatively affecting crops in many world regions. On the other hand, Zn toxicity impairs plant growth, producing physiological alterations, and even cell death. In plants, two of the processes that most determine growth are nitrogen (N) metabolism and photosynthesis. In the last decades, several authors proved that silicon (Si) and calcium (Ca) mitigate the effects of various abiotic and biotic stresses in plants. The objective of this research is to study the effect of Si application to barley (Hordeum vulgare cv. Nure) plants grown under Zn deficiency and Zn toxicity. Hence, barley plants were grown in hydroponics and supplied with a low Zn dose (0.01 mu M ZnSO4) and a high Zn dose (100 mu M ZnSO4) and were supplied with CaSiO3. Parameters related to Zn accumulation, N metabolism, and photosynthesis were measured. Zn stress affected leaf Zn concentration and reduced biomass in barley plants. Both Zn toxicity and deficiency inhibited N metabolism and enhanced photorespiration, increasing stress symptoms. CaSiO3 mitigated Zn stress effects, probably regulating Zn levels in plant cells and enhancing N metabolism and photosynthesis. We conclude that CaSiO3 could be beneficial to grow barley plants in soils with high or low availability of Zn., PAI programme (Plan Andaluz de Investigacion, Grupo de Investigacion) AGR282

Introduction: The cornerstone of rheumatoid arthritis (RA) therapy relies on the treat-to-target strategy, which aims at dampening inflammation as soon as possible in order to achieve persistent low disease activity or, ideally, remission, according to validated disease activity measures. Traditional disease-modifying antirheumatic drugs (DMARDs) may be chosen in monotherapy or in combination as first-line therapy; in case of an unsatisfactory response after a 3-6-month trial, biologic therapy may be commenced. Areas covered: Real-life RA patients may present with concomitant comorbidities/complications or be in peculiar physiological states which raise more than one question as to which biotherapy may be more well suited considering the whole clinical picture. Therefore, a thorough literature search was performed to identify the most appropriate biologic therapy in each setting considered in this review. Expert opinion: Here we provide suggestions for the use of biologic drugs having a predictable better outcome in specific real-world conditions, so as to ideally profile the patient to the best of the current knowledge.

Salinity is an important environmental factor that reduces plant productivity in many world regions. It affects negatively photosynthesis causing a growth reduction. Likewise, calcium (Ca2+) is crucial in plant stress response. Therefore, the modification of Ca2+ cation exchangers (CAX) transporters could be a potential strategy to increase plant tolerance to salinity. Using Targeting Induced Local Lesions in Genomes (TILLING), researchers generated three mutants of Brassica rapa CAX1a transporter: BraA.cax1a-7, BraA.cax1a-4, and BraA.cax1a-12. The aim of this study was to test the effect of those mutations on salt tolerance focusing on the response to the photosynthesis process. Thus, the three BraA.cax1a mutants and the parental line (R-o-18) were grown under salinity conditions, and parameters related to biomass, photosynthesis performance, glucose-6-phosphate dehydrogenase (G6PDH, EC 1.1.1.49), and soluble carbohydrates were measured. BraA.cax1a-4 provided higher biomass and a better photosynthetic performance manifested by higher water use efficiency (WUE), Fv/Fm, electron fluxes, and Rubisco (EC 4.1.1.39) values. In addition, BraA.cax1a-4 presented increased osmotic protection through myo-inositol accumulation. On the other hand, BraA.cax1a-7 produced some negative effects on photosynthesis performance and lower G6PDH and Rubisco accumulations. Therefore, this study points out BraA.cax1a-4 as a useful mutation to improve photosynthetic performance in plants grown under saline conditions.

The aim of this work is to evaluate the effects of freshwater pollution in the heavily contaminated Sarno River (Campania, South Italy), using Pellia neesiana (Pelliaceae Metzgeriales) in order to propose this liverwort as a potential bioindicator, able to record the effects of water pollution, particularly the one related to metal (loid) contamination. Samples of P. neesiana in nylon bags were disposed floating for one week on the waters of Sarno River in three sites characterised by an increasing pollution. As control, some specimens were cultured in vitro in Cd- and Pb-added media, at the same pollutants' levels as measured in the most polluted site. P. neesiana cell ultrastructure was modified and severe alterations were observed in chloroplasts from samples exposed in the most polluted site, and Cd- and Pb-cultured samples. Concurrently, a strong increase in the occurrence of Heat shock proteins 70 (HSP70) was detected in gametophytes following the pollution gradient. In conclusion, ultrastructural damages can be directly related to HSP 70 occurrence in liverwort tissues, and proportional to the degree of pollution present in the river; thus our study suggests P. neesiana as an affordable bioindicator of freshwaters pollution.

The liverwort Lunularia cruciata, known for being a species tolerant to pollution able to colonize urban areas, was collected in the town of Acerra (South Italy) to investigate the biological effects of air pollution in one of the three vertices of the so-called Italian Triangle of Death. The ultrastructural damages observed by transmission electron microscopy in specimens collected in Acerra were compared with samples collected in the city center of Naples and in a small rural site far from sources of air pollution (Riccia, Molise, Southern Italy). The biological response chain to air pollution was investigated considering vitality, photosynthetic efficiency, heat shock protein 70 (Hsp70) induction and gene expression levels, and chlorophyll degradation and related ultrastructural alterations. Particularly, a significant increment in Hsp70 expression and occurrence, and modifications in the chloroplasts' ultrastructure can be strictly related to the environmental pollution conditions in the three sites. The results could be interpreted in relation to the use of these parameters as biomarkers for environmental pollution.

Zn deficiency is currently listed as a major risk factor for human health. Recently, a complimentary solution to mineral malnutrition termed 'biofortification' has been proposed. The aim of this study was to investigate the possible effects of a Zn-biofortification program on Zn levels, amino acidic profile and the phytochemicals content in an edible leafy vegetable, such as Brassica oleracea cv. Bronco. Our results indicate that supplementation of 80-100μM Zn is optimal for maintaining the normal growth of plants and to promote the major Zn concentration in the edible part of B. oleracea. Any further increase of Zn supply induced an accumulation of total amino acids, and increased the enzymatic activities involved in sulfur assimilation and synthesis of phenols, finally resulting in a foliar accumulation of glucosinolates and phenolic compounds. Thus, it could be proposed that the growth of B. oleracea under 80-100μM Zn may increase the intake of this micronutrient and other beneficial compunds for the human health.

Crop production is facing the increase of salinity in soils and irrigation waters. This is a widespread problem that affects crops with high economic importance and reduces yields. Salinity causes oxidative stress in plants which induce complex defensive mechanisms involving the antioxidant system and osmoprotector compounds. Ca2+ plays a pivotal role in counteracting salt stress, and the modification of the Ca2+ vacuolar transporter CAX1 could represent a potential method to improve tolerance to salinity. Three new CAX1 variants in Brassica rapa (BraA.cax1a) were generated using TILLING strategy. The objective of this work is to evaluate the tolerance of these mutants to saline conditions. For this, BraA.cax1a mutants and the parental line R-o-18 were grown in pots under control and saline conditions (150 mM NaCl). Parameters of biomass, ions accumulation, antioxidant compounds concentration and antioxidant enzyme activities, heat shock protein 70 (HSP70) occurrence, and proline (Pro) levels were measured. According to the results, BraA.cax1a-4 mutation provided a higher tolerance to salinity stress. Thus, BraA.cax1a-4 plants showed higher biomass; higher Ca2+ and K+ accumulation in the shoot, a lower Na+/K+ ratio, an enhanced ROS scavenging (increased superoxide dismutase and catalase activities) and an enhanced ascorbate redox state. BraA.cax1a-4 and BraA.cax1a-12 showed higher K+ transport to the shoot which could contribute to their lower lipid peroxidation. In contrast, BraA.cax1a-7 showed a lower antioxidant response. Besides, an increased occurrence of cytosolic and chloroplastic HSP70 isoforms and Pro levels could contribute to protect these B. rapa mutants from saline stress. Therefore, this study identifies a potential useful genotype that could be used to enhance salt tolerance of crops.

The effects of nitrate were studied in wheat varieties grown in hydroponic culture: two landraces (Azizi and Bidi), and two improved genotypes (Om Rabiaa and Khiar) from Tunisia. Nitrogen (N) supply generally induced an increase in plant height in all varieties, albeit to a different extent; interestingly, landraces exhibited the same N Uptake Efficiency (NUpE) as other varieties, and a lower Nitrogen Utilization Efficiency (NUtE); in contrast, improved genotypes exhibit a better NUtE at high N. Nitrate reductase activity (NRA) was sensibly and constitutively higher in the improved genotypes in the roots, while NRA was strongly influenced by nitrate supply in the leaves of Bidi landrace. Glutamine synthetase (GS) activity was similar in all varieties studied, in contrast, ferredoxin-glutamate synthase (Fd- GOGAT) activity and occurrence were increased by nitrate. Intriguingly, glutamate dehydrogenase (GDH) activity followed an opposite behaviour with respect to GOGAT. Glucose-6P-dehydrogenase (G6PDH), which provides reductants for N assimilation, increased in roots upon nitrate supply, but the different plastidial and cytosolic isoforms differently changed in the different varieties studied. The data suggest that landraces present higher metabolic flexibility as compared with improved cultivars; therefore, the metabolic changes observed could be suitable for the identification of factors limiting the NUtE.

Caulerpa is an unusual algal genus from Caulerpaceae (Chlorophyta, Bryopsidales). Species from this family produce a wide range of metabolites suitable for biotechnology applications. Among these, sulfated polysaccharides (SPs) are often highly desirable for pharmaceutical and nutraceutical applications. Here, we provide a classification of sulfotransferases from Caulerpa, these important enzymes catalyze the nodal step for the biosynthesis of SPs. For this, we performed phylogenetic, genomic, expression analyses and prediction of the protein structure on sulfotransferases from Caulerpa. Sequences, domains and structures of sulfotransferases generally shared common characteristics with other plants and algae. However, we found an extensive duplication of sulfotransferase gene family, which is unique among the green algae. Expression analysis revealed specific transcript abundance in the pinnae and rachis of the alga. The unique genomic features could be utilized for the production of complex SPs, which require multiple and specific sulfation reactions. The expansion of this gene family in Caulerpaceae would have resulted in a number of proteins characterizing the unique SPs found in these algae. We provide a putative biosynthetic pathway of SPs, indicating the unique characteristics of this pathway in Caulerpa species. These data may help in the future selection of Caulerpa species for both commercial applications and genetic studies to improve the synthesis of valuable products from Caulerpa.

Introduction: approximately half of Crohn’s disease (CD) patients suffer from concomitant extra-intestinal manifestations (EIMs). Moreover, CD patients may suffer from comorbidities or have physiol...

Nitrogen (N) availability represents one of the most critical factors affecting cultivated crops. N is indeed a crucial macronutrient influencing major aspects, from plant development to productivity and final yield of lignocellulosic biomass, as well as content of bioactive molecules. N metabolism is fundamental as it is at the crossroad between primary and secondary metabolic pathways: Besides affecting the synthesis of fundamental macromolecules, such as nucleic acids and proteins, N is needed for other types of molecules intervening in the response to exogenous stresses, e.g. alkaloids and glucosinolates. By partaking in the synthesis of phenylalanine, N also directly impacts a central plant metabolic ‘hub’—the phenylpropanoid pathway—from which important classes of molecules are formed, notably monolignols, flavonoids and other types of polyphenols. In this review, an updated analysis is provided on the impact that N has on the multipurpose crop hemp (Cannabis sativa L.) due to its renewed interest as a multipurpose crop able to satisfy the needs of a bioeconomy. The hemp stalk provides both woody and cellulosic fibers used in construction and for biocomposites; different organs (leaves/flowers/roots) are sources of added-value secondary metabolites, namely cannabinoids, terpenes, flavonoids, and lignanamides. We survey the available literature data on the impact of N in hemp and highlight the importance of studying those genes responding to both N nutrition and abiotic stresses. Available hemp transcriptomic datasets obtained on plants subjected to salt and drought are here analyzed using Gene Ontology (GO) categories related to N metabolism. The ultimate goal is to shed light on interesting candidate genes that can be further studied in hemp varieties growing under different N feeding conditions and showing high biomass yield and secondary metabolite production, even under salinity and drought.

Nitrogen (N) availability represents one of the most critical factors affecting cultivated crops. N is indeed a crucial macronutrient influencing major aspects, from plant development to productivity and final yield of lignocellulosic biomass, as well as content of bioactive molecules. N metabolism is fundamental as it is at the crossroad between primary and secondary metabolic pathways: Besides affecting the synthesis of fundamental macromolecules, such as nucleic acids and proteins, N is needed for other types of molecules intervening in the response to exogenous stresses, e.g. alkaloids and glucosinolates. By partaking in the synthesis of phenylalanine, N also directly impacts a central plant metabolic ‘hub’—the phenylpropanoid pathway—from which important classes of molecules are formed, notably monolignols, flavonoids and other types of polyphenols. In this review, an updated analysis is provided on the impact that N has on the multipurpose crop hemp (Cannabis sativa L.) due to its renewed interest as a multipurpose crop able to satisfy the needs of a bioeconomy. The hemp stalk provides both woody and cellulosic fibers used in construction and for biocomposites; different organs (leaves/flowers/roots) are sources of added-value secondary metabolites, namely cannabinoids, terpenes, flavonoids, and lignanamides. We survey the available literature data on the impact of N in hemp and highlight the importance of studying those genes responding to both N nutrition and abiotic stresses. Available hemp transcriptomic datasets obtained on plants subjected to salt and drought are here analyzed using Gene Ontology (GO) categories related to N metabolism. The ultimate goal is to shed light on interesting candidate genes that can be further studied in hemp varieties growing under different N feeding conditions and showing high biomass yield and secondary metabolite production, even under salinity and drought.

In this study, the efficacy of