Rumen microbial degradation of bromoform from red seaweed(Asparagopsis taxiformis)and the impact on rumen fermentation and methanogenic archaea

Background The red macroalgae Asparagopsis is an effective methanogenesis inhibitor due to the presence of halogenated methane(CH_(4))analogues,primarily bromoform(CHBr_(3)).This study aimed to investigate the degradation process of CHBr3 from A taxiformis in the rumen and whether this process is diet-dependent.An in vitro batch culture system was used according to a 2×2 factorial design,assessing two A taxiformis inclusion rates[0(CTL)and 2%DM diet(AT)]and two diets[high-concentrate(HC)and high-forage diet(HF)].Incubations lasted for 72 h and samples of headspace and fermentation liquid were taken at 0,0.5,1,3,6,8,12,16,24,48 and 72 h to assess the pattern of degradation of CHBr_(3) into dibromomethane(CH_(2)Br_(2))and fermentation parameters.Additionally,an in vitro experiment with pure cultures of seven methanogens strains(Methanobrevibacter smithii,Methanobrevibacter ruminantium,Methanosphaera stadtmanae,Methanosarcina barkeri,Methanobrevibacter millerae,Methanorhermobacter wolfei and Methanobacterium mobile)was conducted to test the effects of increasing concentrations of CHBr3(0.4,2,10and 50μmol/L).Results The addition of AT significantly decreased CH_(4) production(P=0.002)and the acetate:propionate ratio(P=0.003)during a 72-h incubation.The concentrations of CHBr_(3) showed a rapid decrease with nearly 90%degraded within the first 3 h of incubation.On the contrary,CH_(2)Br_(2) concentration quickly increased during the first 6 h and then gradually decreased towards the end of the incubation.Neither CHBr_(3) degradation nor CH_(2)Br_(2) synthesis were affected by the type of diet used as substrate,suggesting that the fermentation rate is not a driving factor involved in CHBr_(3)degradation.The in vitro culture of methanogens showed a dose-response effect of CHBr3 by inhibiting the growth of M.smithii,M.ruminantium,M.stadtmanae,M.barkeri,M.millerae,M.wolfei,and M.mobile.Conclusions The present work demonstrated that CHBr_(3) from A.taxiformis is quickly degraded to CH_(2)Br_(2)in the rumen and that the fermentation rate promoted by different diets is not a driving factor involved in CHBr_(3)degradation.

Genome-wide QTL analysis of tomato fruit cuticle deposition and composition

Genetics of traits related to fruit cuticle deposition and composition was studied in two red-fruited tomato species.Two mapping populations derived from the cross between the cultivated tomato(Solanum lycopersicum L.)and its closest relative wild species Solanum pimpinellifolium L.were employed to conduct a QTL analysis.A combination of fruit cuticle deposition,components and anatomical traits were investigated and the individual effect of each QTL evaluated.A total of 70 QTLs were identified,indicating that all the cuticle traits analyzed have a complex polygenic nature.A combination of additive and epistatic interactions was observed for all the traits,with positive contribution of both parental lines to most of them.Colocalization of QTLs for various traits uncovered novel genomic regions producing extensive changes in the cuticle.Cuticle density emerges as an important trait since it can modulate cuticle thickness and invagination thus providing a strategy for sustaining mechanical strength without compromising palatability.Two genomic regions,located in chromosomes 1 and 12,are responsible for the negative interaction between cuticle waxes and phenolics identified in tomato fruit.Several candidate genes,including transcription factors and structural genes,are postulated and their expression analyzed throughout development.

Chemistry and particle size distribution of respirable coal dust in underground mines in Central Eastern Europe

Despite international efforts to limit worker exposure to coal dust,it continues to impact the health of thousands of miners across Europe.Airborne coal dust has been studied to improve risk models and its control to protect workers.Particle size distribution analyses shows that using spraying systems to suppress airborne dusts can reduce particulate matter concentrations and that coals with higher ash yields produce finer dust.There are marked chemical differences between parent coals and relatively coarse deposited dusts(up to _(500)μm,DD_(500)).Enrichments in Ca,K,Ba,Se,Pb,Cr,Mo,Ni and especially As,Sn,Cu,Zn and Sb in the finest respirable dust fractions could originate from:(i)mechanical machinery wear;(ii)variations in coal mineralogy;(iii)coal fly ash used in shotcrete,and carbonates used to reduce the risk of explosions.Unusual enrichments in Ca in mine dusts are attributed to the use of such concrete,and elevated K to raised levels of phyllosilicate mineral matter.Sulphur concentrations are higher in the parent coal than in the DD_(500),probably due to relatively lower levels of organic matter.Mass concentrations of all elements observed in this study remained below occupational exposure limits.

Mid and late Holocene forest fires and deforestation in the subalpine belt of the Iberian range,northern Spain

The conversion of subalpine forests into grasslands for pastoral use is a well-knownphenomenon, although for most mountain areas the timing of deforestation has not been determined. The presence of charcoal fragments in soil profiles affected by shallow landsliding enabled us to date the occurrence of fires and the periods of conversion ofsubalpine forest into grasslands in the Urbión Mountains, Iberian Range, Spain. We found that the treeline in the highest parts of the northwestern massifs of the Iberian Range(the Urbión, Demanda, Neila, and Cebollera massifs) is currently between 1500 and 1600 m a.s.l., probably because of pastoral use of the subalpine belt, whereas in the past it would have reached almost the highest divides(at approximately 2100–2200 m a.s.l.). The radiocarbon dates obtained indicate that the transformation of the subalpine belt occurred during the Late Neolithic, Chalcolithic, Bronze Age, Iron Age, and Middle Ages. Forest clearing was probably moderate during fires prior to the Middle Ages, as the small size of the sheep herds and the local character of the markets only required small clearings, and therefore more limited fires. Thus, it is likely that the forest recovered burnt areas in a few decades; this suggests the management of the forest and grasslands following a slash-andburn system. During the Middle and Modern Ages deforestation and grassland expansion affected most of the subalpine belt and coincided with the increasing prevalence of transhumance, as occurred in other mountains in the Iberian Peninsula(particularly the Pyrenees). Although the occurrence of shallow landslides following deforestation between the Neolithic and the Roman Period cannot be ruled out, the most extensive shallow landsliding processes would have occurred from the Middle Ages until recent times.

Temperature-Dependent Structure of Epitaxial （Ba,Sr）TiOa Films Grown on SrRuO3-Covered SrTiO3 Substrates

Growth dynamics of epitaxiai （Ba, Sr）TiO3 thin films deposited at different temperatures on SrRuO3/SrTiO3 substrates by pulsed laser deposition is investigated by transmission electron microscopy. The films exhibit a layered structure comprising sublayers with distinctive features in regard to the remaining strain, density of misfit dislocations and/or lattice defects, and growth habit. We correlate these temperature-dependent features with the predominant misfit-strain relaxation mechanisms for each one of the detected growth regimes. The thickness dependence of the film structure is discussed within the framework of the predictions for a kineticaily modified Stranski-Krastanov growth mode.

Are Ni/and Ni5Fe1/biochar catalysts suitable for synthetic natural gas production?A comparison with g-Al2O3 supported catalysts

Among challenges implicit in the transition to the post-fossil fuel energetic model,the finite amount of resources available for the technological implementation of CO_(2) revalorizing processes arises as a central issue.The development of fully renewable catalytic systems with easier metal recovery strategies would promote the viability and sustainability of synthetic natural gas production circular routes.Taking Ni and NiFe catalysts supported over g-Al_(2)O_(3) oxide as reference materials,this work evaluates the potentiality of Ni and NiFe supported biochar catalysts for CO_(2) methanation.The development of competitive biochar catalysts was found dependent on the creation of basic sites on the catalyst surface.Displaying lower Turn Over Frequencies than Ni/Al catalyst,the absence of basic sites achieved over Ni/C catalyst was related to the depleted catalyst performances.For NiFe catalysts,analogous Ni_(5)Fe_(1) alloys were constituted over both alumina and biochar supports.The highest specific activity of the catalyst series,exhibited by the NiFe/C catalyst,was related to the development of surface basic sites along with weaker NiFe-C interactions,which resulted in increased Ni0:NiO surface populations under reaction conditions.In summary,the present work establishes biochar supports as a competitive material to consider within the future low-carbon energetic panorama.

Projected near-surface wind speed and wind energy over Central Asia using dynamical downscaling with bias-corrected global climate models

Wind energy development in Central Asia can help alleviate drought and fragile ecosystems.Nevertheless,current studies mainly used the global climate models(GCMs)to project wind speed and energy.The simulated biases in GCMs remain prominent,which induce a large uncertainty in the projected results.To reduce the uncertainties of projected near-surface wind speed(NSW)and better serve the wind energy development in Central Asia,the Weather Research and Forecasting(WRF)model with bias-corrected GCMs was employed.Compared with the outputs of GCMs,dynamical downscaling acquired using the WRF model can better capture the high-and low-value centres of NSWS,especially those of Central Asia's mountains.Meanwhile,the simulated NSWS bias was also reduced.For future changes in wind speed and wind energy,under the Representative Concentration Pathway 4.5(RCP4.5)scenario,NSWS during 2031-2050 is projected to decrease compared with that in 19862005.The magnitude of NSwS reduction during 2031-2050 willreach 0.1 m s^(-1).and the maximum reduction is projected to occur over the central and western regions(>0.2 m s^(-1)).Furthermore,future wind power density(WPD)can reveal nonstationarity and strong volatility,although a downward trend is expected during 2031-2050.In addition,the higher frequency of wind speeds at the turbine hub height exceeding 3.0 m s^(-1)can render the plain regions more suitable for wind energy development than the mountains from 2031 to 2050.This study can serve as a guide in gaining insights into future changes in wind energy across Central Asia and provide a scientific basis for decision makers in the formulation of policies for addressing climate change.

Roscovitine sensitizes breast cancer cells to TRAIL-induced apoptosis through a pleiotropic mechanism

The tumor necrosis factor （TNF）-related apoptosis-inducing ligand （TRAIL/APO2L） is a member of the TNF gene superfamily that induces apoptosis upon engagement of cognate death receptors. While TRAIL is relatively non-toxic to normal cells, it selectively induces apoptosis in many transformed cells. Nevertheless, breast tumor cells are particularly resistant to the effects of TRAIL. Here we report that, in combination with the cyclin-dependent kinase inhibitor roscovitine, exposure to TRAIL induced marked apoptosis in the majority of TRAIL-resistant breast cancer cell lines examined. Roscovitine facilitated TRAIL death-inducing signaling complex formation and the activation of caspase-8. The cFLIPL and cFLIPs FLICE-inhibitory proteins were significantly down-regulated following exposure to roscovitine and, indeed, the knockdown of cFLIP isoforms by siRNA sensitized breast tumor cells to TRAIL-induced apoptosis. In addition, we demonstrate that roscovitine strongly suppressed Mcl-1 expression and up-regulated E2F1 protein levels in breast tumor ceils. Significantly, the silencing of Mci-1 by siRNA sensitized breast tumor cells to TRAIL-induced apoptosis. Furthermore, the knockdown of E2F1 protein by siRNA reduced the sensitizing effect of roscovitine in TRAIL-induced apoptosis. In summary, our results reveal a pleitropic mechanism for the pro-apoptotic influence of roscovitine, highlighting its potential as an antitumor agent in breast cancer in combination with TRAIL.

Synthesis of glass ceramics from kaolin and dolomite mixture

Cordierite- and anorthite-based binary glass ceramics of the CaO-MgO-Al2O3-SiO2 （CMAS） system were synthesized by mixing local and abundant raw minerals （kaolin and doloma by mass ratio of 82/18）. A kinetics study reveals that the activation energy of crystalli- zation （Ea） calculated by the methods of Kissinger and Marotta are 438 kJ·mol^-1 and 459 kJ·mol^-1, respectively. The Avrami parameter （n） is estimated to be approximately equal to 1, corresponding to the surface crystallization mechanism. X-ray diffraction （XRD） analysis shows that the anorthite and cordierite crystals are precipitated from the parent glass as major phases. Anorthite crystals first form at 850℃, whereas the μ-cordierite phase appears after heat treatment at 950℃. Thereafter, the cordierite allotropically transforms to α-cordierite at 1000℃. Complete densification is achieved at 950℃; however, the density slightly decreases at higher temperatures, reaching a stable value of 2.63 kg·m^-3 between 1000℃ and 1100℃, The highest Vickers hardness of 6 GPa is also obtained at 950℃. However, a substantial decrease in hardness is recorded at 1000℃; at higher sintering temperatures, it slightly increases with increasing temperature as the ct-cordierite crystallizes.

Pedigree analysis of 220 almond genotypes reveals two world mainstream breeding lines based on only three different cultivars

Loss of genetic variability is an increasing challenge in tree breeding programs due to the repeated use of a reduced number of founder genotypes.However,in almond,little is known about the genetic variability in current breeding stocks,although several cases of inbreeding depression have been reported.To gain insights into the genetic structure in modern breeding programs worldwide,marker-verified pedigree data of 220 almond cultivars and breeding selections were analyzed.Inbreeding coefficients,pairwise relatedness,and genetic contribution were calculated for these genotypes.The results reveal two mainstream breeding lines based on three cultivars:“Tuono”,“Cristomorto”,and“Nonpareil”.Descendants from“Tuono”or“Cristomorto”number 76(sharing 34 descendants),while“Nonpareil”has 71 descendants.The mean inbreeding coefficient of the analyzed genotypes was 0.041,with 14 genotypes presenting a high inbreeding coefficient,over 0.250.Breeding programs from France,the USA,and Spain showed inbreeding coefficients of 0.075,0.070,and 0.037,respectively.According to their genetic contribution,modern cultivars from Israel,France,the USA,Spain,and Australia trace back to a maximum of six main founding genotypes.Among the group of 65 genotypes carrying the S f allele for self-compatibility,the mean relatedness coefficient was 0.125,with“Tuono”as the main founding genotype(24.7%of total genetic contribution).The results broaden our understanding about the tendencies followed in almond breeding over the last 50 years and will have a large impact into breeding decision-making process worldwide.Increasing current genetic variability is required in almond breeding programs to assure genetic gain and continuing breeding progress.

Hematotesticular barrier is altered from early stages of liver cirrhosis:Effect of insulin-like growth factor 1

AIM:The pathogenesis of hypogonadism in liver cirrhosis is not well understood.Previous results from our laboratory showed that IGF-1 deficiency might play a pathogenetic role in hypogonadism of cirrhosis.The administration of IGF-1 for a short period of time reverted the testicular atrophy associated with advanced experimental cirrhosis. The aim of this study was to establish the historical progression of the described alterations in the testes, explore testicular morphology,histopathology,cellular proliferation,integrity of testicular barrier and hypophyso- gonadal axis in rats with no ascitic cirrhosis. METHODS:Male Wistar rats with histologically-proven cirrhosis induced with carbon tetrachloride(CCI_4)for 11 wk, were allocated into two groups(n=12,each)to receive recombinant IGF-1(2 μg/100 gd,sc)for two weeks or vehicle.Healthy rats receiving vehicle were used as control group(n=12). RESULTS:Compared to controls,rats with compensated cirrhosis showed a normal testicular size and weight and very few histopathological testicular abnormalities. However,these animals showed a significant diminution of cellular proliferation and a reduction of testicular transferrin expression.In addition,pituitary-gonadal axis was altered,with significant higher levels of FSH(P<0.001 vscontrols)and increased levels of LH in untreated cirrhotic animals.Interestingly,IGF-1 treatment normalized testicular transferrin expression and cellular proliferation and reduced serum levels of LH(P=ns vs controls,and P<0.01 vs untreated cirrhotic group). CONCLUSION:The testicular barrier is altered from an early stage of cirrhosis,shown by a reduction of transferrin expression in Sertoli cells,a diminished cellular proliferation and an altered gonadal axis.The treatment with IGF-1 could be also useful in this initial stage of testicular disorder associated with compensated cirrhosis.

Benthic microbial biogeography along the continental shelf shaped by substrates from the Changjiang River plume

Coastal zones are active reactors of continental material including that transported by rivers via a series of microbiota-mediated reactions. Nevertheless, current knowledge of the ecology and functioning of the microbiota in coastal areas affected by large riverine inputs remains insufficient on a global scale. Here, an investigation on sediment microbial composition, including taxonomy and metabolic network, as well as their relationship with major benthic reaction substrates, namely carbon, nitrogen, sulphur and phosphorus, was conducted in the continental shelf affected by the spread of the Changjiang River plume. Surface sediment samples(48 samples)were collected during March 2018, obtaining a mean Operational Taxonomic Units(OTUs) number of 3 341.Proteobacteria, Acidobacteria and Actinobacteria were abundant phyla in the studied sediments. Bray-Curtis distance analysis classified the 48 samples into 4 clusters(MG1 to MG4) at the phylum-level. MG1 and MG2 are found near the river mouth, receiving substantial land-derived particles from the Changjiang River runoff.Particle-attached microbes may be settled in these regions and influenced the observed sediment microbial diversity and biomass, e.g., increased Crenarchaeota relative abundance. The relative enrichment of these two groups in heterotrophic microbes further suggests a reliance of benthic microbiota on substrates with terrestrial origin, particularly specialized on processing sulphur-rich substrates. Regions MG3 and MG4 are located in the outer margin of the area affected by the Changjiang River plume, mainly fed by settling pelagic particles from phytoplankton. Compared to MG1 and MG2, a significant increase in the abundance of Thaumarcheota(phylumlevel) and Nitrosopumilus(genus-level) was found in MG3, suggesting nitrogen-related transformations as the key reactions to sustain microbial metabolism in this region. Coupled with the identified variations in the taxonomic composition, significant differences in the keystone taxa between MG1/MG2 and MG3/MG4 were identified via OTU co-occurrence analyses. A higher abundance of Actinobacteria, Thaumarchaeota and Acidobacteria in MG3 and MG4 reinforced the identified spatial variability in benthic metabolism and highlighted the significance of substrate inputs on the sediment microbial structure and biogeography.

Pleiotrophin fights Brd2 for neuronal differentiation

Bromodomain containing 2 （Brd2） protein belongs to the Bromodomains and Extra Terminal domain （BET） family of chromatin adaptors characterized by the presence of two N-terminal tandem bromodomains and an exclusive C-terminal extra terminal domain （ET） （Belkina and Denis, 2012; Shi and Vakoc, 2014）. Bromodomains are involved in recognizing acetylated histone tails and other acetylated proteins while the ET domain has been implicated in protein-protein interaction.

（Re）Ciphering Nations： Greece as a Constructed Illegibility in Odysseas Elytis＇s Poetry

In their attempt to construct their identity in opposition to European one, non-Western new nations with alphabets such as Greek, Hebrew, or Cyrillic, used them as a way of emphasizing difference, and thus provide symbolic spaces for the newborn nations. The illegibility of these alphabets for Western people, along with the ancient prestige of at least Hebrew and Greek, fostered the illusion of temporal continuity and provided legitimacy to their atomization projects. Odysseas Elytis （1911-1996）, Nobel Prize for Literature winner in 1979 and the last national poet of Greece, blends this old tendency in Greek culture and the broader claim of modern European poets for the essential autonomy of art and literature. His efforts to reinforce the walls separating Greece from Latin-Western culture by reinforcing the illegibility of both Greek and poetic idioms, aim at constructing a more essential Greece, founded on aesthetics, language, and writing instead of politics, institutions, or geographic borders. In this paper engaging mainly in the fields of literary and postcolonial studies, the author intends to analyze the mechanisms by which language, writing, or literature can be used to （re）cipher once again the already exclusive concept of nation, and thus to undermine every possibility of deciphering and translatability. He concludes that in “conceptually colonized” nations such as Greece, this process implies and anticolonial movement still caught nevertheless in a colonial discursivity.

断弯褶皱作用运动学定量研究法

欧拉变形速率方程和块体接触条件可用于定量研究断弯褶皱运动学。用该方法可以将活动轴面(速率边界)的方位和穿过该界面所需的滑动定量化。该方法是综合性的,它包括了以前提出的断弯褶皱作用的几何模型。

The Vascular Vegetation Populating the Flora in Building Materials of Historic Monuments Cities of the West Central Region of Morocco

In the concern of the preservation of the main historic monuments of the cities of Rabat and Sale (Morocco), a botanical study was conducted in 2009. The prospecting of these monuments allowed raising an inventory of the flora populating their building materials, and it has proved that this flora is rich and diversified. Indeed, it consists of 171 adventitious species distributed in 46 botanical families. The most represented families are Asteraceae, Poaceae, Fabaceae, Caryophyllaceae, Geraniaceae, Brassicaceae and Lamiaceae. They supply, to them only 49.7% of the specific size. The annual therophytes and the dicotyledon are dominant with respectively 66.7% and 84.7% of the specific size. Nevertheless, the presence of more than 20 species of trees and perennials constitutes a serious danger for bulwarks walls, especially by the phenomenon of fissuring by the action of the huge roots of these vegetables. These vegetables fitting into are placed on joints or cracks fissures have a chemical action on stones by acids that they release, and also a mechanical action by the growth of roots inside cracks fissures. They remain one of these are one of the important biological factors of the degradation of historic monuments. It is to note that the bulwarks walls of the site of Chella (Roman ruins) present more floral diversity than the other canvassed monuments (91 species) that are 53% of the total size.

CONSTANS alters the circadian clock in Arabidopsis thaliana

Plants are sessile organisms that have acquired highly plastic developmental strategies to adapt to the environment.Among these processes,the floral transition is essential to ensure reproductive success and is finelyregulated by several internal andexternal genetic networks.The photoperiodic pathway,which controls plant response to day length,is one of the most important pathways controlling flowering.In Arabidopsis photoperiodic flowering,CONSTANS(CO)is the central gene activating the expression of the florigen FLOWERING LOCUS T(FT)in the leaves at the end of a long day.The circadian clock strongly regulates Co expression.However,to date,no evidence has been reported regarding a feedbackloop from the photoperiod pathway back to the circadian clock.Using transcriptional networks,we have identified relevant network motifs regulating the interplay between the circadian clock and the photoperiod pathway.Gene expression,chromatin immunoprecipitation experiments,and phenotypic analysis allowed us to elucidate the role of Co over the circadian clock.Plants with altered cO expression showed a different internal clock period,measured by daily leaf rhythmic movements.We showed that co upregulates the expression of key genes related to the circadian clock,such as CCA1,LHY,PRR5,and Gl,at the end of a long day by bindingto specific sites on their promoters.Moreover,a high numberof PRR5-repressed target genes are upregulated by CO,and this could explain the phase transition promoted by CO.The CO-PRR5 complex interacts with the bZiP transcriptionfactor HY5andhelps to localize the complex in the promoters of clock genes.Taken together,our results indicate that there may be a feedback loop in which co communicates back to the circadian clock,providing seasonal information to the circadian system.

The Phosphate Transporter PHT4;6 Is a Determinant of Salt Tolerance that Is Localized to the Golgi Apparatus of Arabidopsis

Insertion mutations that disrupt the function of PHT4;6 （At5g44370） cause NaCI hypersensitivity of Arabidopsis seedlings that is characterized by reduced growth of the primary root, enhanced lateral branching, and swelling of root tips. Mutant phenotypes were exacerbated by sucrose, but not by equiosmolar concentrations of mannitol, and attenuated by low inorganic phosphate in the medium. Protein PHT4;6 belongs to the Major Facilitator Superfamily of permeases that shares significant sequence similarity to mammalian type-I Pi transporters and vesicular glutamate transporters, and is a member of the PHT4 family of putative intracellular phosphate transporters of plants. PHT4;6 localizes to the Golgi membrane and transport studies indicate that PHT4;6 facilitates the selective transport of Pi but not of chloride or inorganic anions. Phenotypic similarities with other mutants displaying root swelling suggest that PHT4;6 likely functions in protein N-glycosylation and cell wall biosynthesis, which are essential for salt tolerance. Together, our results indicate that PHT4;6 transports Pi out of the Golgi lumenal space for the re-cycling of the Pi released from glycosylation processes.

Thickness determination of MoS2,MoSe2,WS2 and WSe2 on transparent stamps used for deterministic transfer of 2D materials

Here,we propose a method to determine the thickness of the most common transition metal dichalcogenides (TMDCs) placed on the surface of transparent stamps,used for the deterministic placement of two-dimensional materials,by analyzing the red,green and blue channels of transmission-mode optical microscopy images of the samples.In particular,the blue channel transmittance shows a large and monotonic thickness dependence,making it a very convenient probe of the flake thickness.The method proves to be robust given the small flake-to-flake variation and the insensitivity to doping changes of MoS2.We also tested the method for MoSe2,WS2 and WSe2.These results provide a reference guide to identify the number of layers of this family of materials on transparent substrates only using optical microscopy.

Mitochondrial Sulfide Detoxification Requires a Functional Isoform O-Acetylserine（thiol）lyase C in Arabidopsis thaliana

In non-cyanogenic species, the main source of cyanide derives from ethylene and camalexin biosyntheses. In mitochondria, cyanide is a potent inhibitor of the cytochrome c oxidase and is metabolized by the β-cyanoalanine synthase CYS-C1, catalyzing the conversion of cysteine and cyanide to hydrogen sulfide and β-cyanoalanine. The hydrogen sulfide released also inhibits the cytochrome c oxidase and needs to be detoxified by the O-acetylserine（thiol）lyase mitochondrial isoform, OAS-C, which catalyzes the incorporation of sulfide to O-acetylserine to produce cysteine, thus generating a cyclic pathway in the mitochondria. The loss of functional OAS-C isoforms causes phenotypic characteristics very similar to the loss of the CYS-C1 enzyme, showing defects in root hair formation. Genetic complementation with the OAS-Cgene rescues the impairment of root hair elongation, restoring the wild-type phenotype. The mitochondria compromise their capacity to properly detoxify cyanide and the resulting sulfide because the latter cannot re-assimilate into cysteine in the oas-c null mutant. Consequently, we observe an accumulation of sulfide and cyanide and of the alternative oxidase, which is unable to prevent the production of reactive oxygen species probably due to the accumulation of both toxic molecules. Our results allow us to suggest that the significance of OAS-C is related to its role in the proper sulfide and cyanide detoxification in mitochondria.