Transceptors at the boundary of nutrient transporters and receptors: a new role for Arabidopsis SULTR1;2 in sulfur sensing

Plants have evolved a sophisticated mechanism to sense the extracellular sulfur (S) status so that sulfate transport and S assimilation/metabolism can be coordinated. Genetic, biochemical, and molecular studies in Arabidopsis over the past 10 years have started to shed some light on the regulatory mechanism of the S response. Key advances in transcriptional regulation (SLIM1, MYB, and miR395), involvement of hormones (auxin, cytokinin, and abscisic acid) and identification of putative sensors (OASTL and SULTR1;2) are highlighted here. Although our current view of S nutrient sensing and signaling remains fragmented, it is anticipated that through further studies a sensing and signaling network will be revealed in the near future

Sidi Rahman Oil Discovery in Egypt A Big Exploration Step in an Area of Lost Interest

Pretvaranje nezanimljivog područja, uključujući brojne neuspjele bušotine, u naftno privlačno područje je izazov s kojim se suočuje istraživanje kada se obavlja na području koji su drugi napustili, a na kraju se ipak pronađu nove rezerve ugljikovodika. Od vremena prvog otkrića u doba Prvog svjetskog rata, otkrivena su brojna naftna polja u Egiptu, ali ni jedno nije pronađeno duž 1 200 km mediteranskog obalnog pojasa pa je to područje napušteno kao nezanimljivo za istraživanje. Izgradnja novog konceptualnog geomodela, kakav dosada nije primijenjen, bio je imperativ na putu prema uspjehu. Male obveze u prvoj istražnoj fazi East Yidma koncesije bile su uzrok fokusiranja pažnje na ograničeno područje. Usprkos oskudnosti podataka osmišljen je naftni model. Postojanje velikih prepreka, uključujući minska polja iz drugog svjetskog rata i turističkih lokaliteta duž obale, nije promijenilo odluku da se pažnja usredotoči na sjeverozapadni dio koncesije. Oskudni seizmički podaci i malo prekrivanje bili su razlog za seizmička snimanja specifičnog dizajna, čiji su konačni rezultati potkrijepili i ažurirali prijašnji naftni model. Velika važnost je dana procjeni dvaju potpuno različitih ciljeva istraživanja s maksimalnom razlikom u nivou strukturalnog izdizanja. Bušotina Drazia-1 izabrana je kako bi se ispitalo duboko riftno korito, dok je bušotina Sidi Rahman-1, smještena na kraju jednog starog seizmičkog profila, imala za cilj prodrijeti u visoko izdignuti strukturni hrbat. Unatoč rezultatima konvencionalnih tehnika i primjene nekoliko nekonvencionalnih alatki, kao što je akustička spektroskopija, na osnovi kojih je zaključeno da na području Sidi Rahmana postoji mala vjerojatnost pronalaska ugljikovodika, odlučeno je da se ta lokacija ispita. Bušotina Drazia-1 potvrdila je akumulacije nafte zaključno s dubinom 3 901 m (12 800 ft) u baremskom ležištu, dok je u bušotini Sidi Rahman-1 nađena nafta na dosada najmanjoj poznatoj dubini od 1 914 m (6 280 ft) u donjocenomanskom pješčenjaku i 7 produktivnih zona do dubine 3 840 m (12 600 ft). Posljednja Inina otkrića oživjela su zanimanje i privukla investiranje internacionalnih kompanija u egipatski mediteranski obalni pojas.Converting an unattractive area, including numerous failed wells, into an oil attractive area is the challenge facing exploration when applying for an acreage previously relinquished by others, and finally achieving new hydrocarbon reserves. Since the first discovery during World War I (WWI), numerous oil fields were discovered in Egypt but none of them was found along the 1 200 km Mediterranean coastal strip, leaving the area unattractive for exploration. To build a new conceptual geomodel, not applied before, was imperative on the road to success. A small commitment for the first exploration phase of East Yidma Concession has triggered the needs to focus on a restricted area. Despite scarcity of data, a petroleum model has been reached. The presence of tough obstacles, including WWII mine fields and tourist sites along the coast, did not change the decision to focus on northwestern part of the concession. Poor seismic data and coverage was the reason to acquire seismic survey with a specific design, whose final results supported and updated the previously achieved petroleum model. High importance was given to evaluation of two completely separated plays with maximum elevation difference. Drazia-1 well was selected to test a deep rift-trough while Sidi Rahman-1, positioned on a tail of an old seismic line, aimed to penetrate a high stand structural ridge. Despite the results of conventional techniques and some non-conventional tools as acoustic spectroscopy that identified Sidi Rahman area as of low probability, it was decided to test the location. Drazia-1 proved oil accumulation down to 3 901 m (12 800 ft) in Barremian reservoir, while Sidi Rahman-1 tested the shallowest known oil at 1 914 m (6 280 ft) in Lower Cenomanian sandstone and 7 pay-zones down to 3 840 m (12 600 ft). The recent discoveries of INA re-triggered the interest and attracted international companies to invest in Egypt’s Mediterranean coastal strip

The sulfur pathway and diagnosis of sulfate depletion in grapevine

Sulfur is an essential nutrient to all plant species. Plants assimilate sulfur in a well-described pathway, which has been taken up by roots. Regulatory mech- anism has been the subject of many research papers. However, recent studies highlighted differences between crop plants and the model plant Arabidopsis thaliana. Our work focuses on the identification of genes involved in the sulfur metabolism in the Vitis vinifera genome, and their response to sulfur deficiency and other abiotic stress endured by grapevine in the field, namely water stress. Here, we describe the identification and brief characterization of the first assimilation enzymes involved in the sulfur pathway, the enzyme responsible for sulfur activa- tion, ATP sulfurylase (ATPS), and the two enzymes that reduce sulfate to sulfide, Adenosine 50-phosphosulate reductase (APR) and Sulfite reductase (SiR). A reduc- tion was observed in the number of ATPS and APR isoforms identified in V. vinifera genome when compared to A. thaliana or Glycine max genomes. Two ATPS isoforms were present in the Vitis genome, of which only ATPS1 transcript was detected in the tested tissues, and one APR isoform, suggesting an absence of redundancy in the role of both enzymes. ATPS1, APR and SiR transcript level was up-regulated in response to 2 days exposure to sulfur deficiency in V. vinifera cell cultures, which was completely reversed by the addition of GSH to the culture medium. Apparently, oxidative stress triggered GSH has a pivotal role in the regulation of ATPS1, APR and SiR transcription level, since their up-regulation was observed in mRNA from field grapevine berries under water stress, which is known to induce oxidative stress.info:eu-repo/semantics/publishedVersio

Bioassimilable sulphur provides effective control of Oidium neolycopersici in tomato, enhancing the plant immune system

BACKGROUND: Developments of alternatives to the use of chemical pesticides to control pests are focused on the induction of natural plant defences. The study of new compounds based on liquid bioassimilable sulphur and its effect as an inductor of the immune system of plants would provide an alternative option to farmers to enhance plant resistance against pathogen attacks such as powdery mildew. In order to elucidate the efficacy of this compound in tomato against powdery mildew, we tested several treatments: curative foliar, preventive foliar, preventive in soil drench and combining preventive in soil drench and curative foliar. RESULTS: In all cases, treated plants showed lower infection development, better physiological parameters and a higher level of chlorophyll. We also observed better performance in parameters involved in plant resistance such as antioxidant response, callose deposition and hormonal levels. CONCLUSION: The results indicate that preventive and curative treatments can be highly effective for the prevention and control of powdery mildew in tomato plants. Foliar treatments are able to stop the pathogen development when they are applied as curative. Soil drench treatments induce immune response mechanisms of plants, increasing significantly callose deposition and promoting plant development

The role of bacteria and mycorrhiza in plant sulfur supply

peer-reviewedPlant growth is highly dependent on bacteria, saprophytic, and mycorrhizal fungi which facilitate the cycling and mobilization of nutrients. Over 95% of the sulfur (S) in soil is present in an organic form. Sulfate-esters and sulfonates, the major forms of organo-S in soils, arise through deposition of biological material and are transformed through subsequent humification. Fungi and bacteria release S from sulfate-esters using sulfatases, however, release of S from sulfonates is catalyzed by a bacterial multi-component mono-oxygenase system. The asfA gene is used as a key marker in this desulfonation process to study sulfonatase activity in soil bacteria identified as Variovorax, Polaromonas, Acidovorax, and Rhodococcus. The rhizosphere is regarded as a hot spot for microbial activity and recent studies indicate that this is also the case for the mycorrhizosphere where bacteria may attach to the fungal hyphae capable of mobilizing organo-S. While current evidence is not showing sulfatase and sulfonatase activity in arbuscular mycorrhiza, their effect on the expression of plant host sulfate transporters is documented. A revision of the role of bacteria, fungi and the interactions between soil bacteria and mycorrhiza in plant S supply was conducted