Sulfur Metabolism Research Articles

Metagenomic analysis revealed the evolution of microbial communities, metabolic pathways, and functional genes in the heterotrophic nitrification-aerobic denitrification process under La3+ stress

Trivalent lanthanum (La3+) exists widely in ammonia nitrogen (NH4+-N) tailing water from ionic rare earth mines; however, its effect on heterotrophic nitrification-aerobic denitrification (HN-AD) is unknown, thereby limiting the application of the HN-AD process in this field. In this study, we conducted an HN-AD process using a sequencing batch reactor (5 L) that was continuously operated to directly treat acidic (NH4)2SO4 wastewater (influent NH4+-N concentration of approximately 110 mg/L and influent pH of 5) containing different La3+ concentrations (0–100 mg/L). The NH4+-N removal efficiency of the reactor reached 98.25 % at a La3+ concentration of 100 mg/L. The reactor was in a neutral-to-alkaline environment, which favored La3+ precipitation and complexation. Metagenomic analysis revealed that the relative abundance of Thauera in the reactor remained high (88.62–92.27 %) under La3+ stress. The relative abundances of Pannonobacter and Hyphomonas significantly increased, whereas that of Azoarcus significantly decreased. Metabolic functions in the reactor were mainly contributed by Thauera, and the abundance of metabolic functions under low La3+ stress (≤5 mg/L) significantly differed from that under high La3+ stress (≥10 mg/L). The relative abundance of ammonia assimilation-related genes in the reactor was high and significantly correlated with ammonia removal. However, traditional ammonia oxidation genes were not annotated, and unknown ammonia oxidation pathways may have been present in the reactor. Moreover, La3+ stimulated amino acid biosynthesis and translocation, the citrate cycle, sulfur metabolism, and oxidative phosphorylation and promoted the overproduction of extracellular polymeric substances, which underwent complexation and adsorbed La3+ to reduce its toxicity. Our results showed that the HN-AD process had a strong tolerance to La3+, stable NH4+-N removal efficiency, the potential to recover La3+, and considerable application prospects in treating NH4+-N tailing water from ionic rare earth mines.

Interactions of long-term grazing and woody encroachment can shift soil biogeochemistry and microbiomes in savanna ecosystems

Semi-arid grasslands and savannas in the southern Great Plains USA are extensively used for livestock grazing. Over the past century, Juniperus (juniper) and Quercus (oak) species abundance have increased due to intensive grazing and reduced fire frequency. We investigated the interactions between livestock grazing history (none, moderate, heavy) and vegetation cover (grassland, juniper, oak) using a ∼ 70-year grazing experiment in west-central Texas. We explored effects on soil organic carbon (SOC), total nitrogen (TN), total phosphorus (TP), microbial community composition, and function. SOC and TN were 50–150 % higher under juniper and oak compared to grasslands, and 10–30 % lower in grazed vs. ungrazed areas. Vegetation × grazing interaction showed greater SOC and TN loss under oak than juniper or grasslands. Ungrazed controls had higher soil TP than grazed areas, with oak and juniper soils having more TP than grasslands. Bacterial and fungal communities differed between grassland and woody vegetation. Grazing affected only bacterial communities. SOC, TN, TP accounted for differences in community structure. Abundances of genes related to methane, nitrogen, sulfur metabolisms, and dominant fungal trophic modes were linked to soil C, N, P ratios. These findings highlight how long-term livestock grazing and woody plant encroachment influence soil C, N, P cycles, altering soil microbial community structure and function. This study provides insights for savanna ecosystem management and integrating land cover effects into biogeochemical models for global change scenarios.

4-Aminophenylboronic acid dimer sensitized carbon nanotubes for the construction of portable and disposable sulfide electrochemical sensors

Abnormal sulfide levels in serum can cause kidney failure, Alzheimer's, Parkinson's, stroke, diabetes, and even cancer. Therefore, maintaining proper sulfide balance is crucial for managing and preventing these conditions. Electrochemical approaches have emerged as potential alternatives for sulfide detection. However, the adsorption of elemental sulfur on the working electrode leads to surface fouling and passivation, posing a significant challenge in developing reliable electrochemical methods for sulfide detection. In this study, we present a portable and surface fouling-free electrochemical system that utilizes functionalized multi-walled carbon nanotubes and 4-aminophenylboronic acid dimers for accurate sulfide measurement. The sensor showed excellent electrocatalytic activity to sulfide and antifouling activity to possible interferences. The method had a linear range from 10 µM to 2 mM and a detection limit of 2.3 µM. The effectiveness and applicability of this method were evaluated by analyzing sulfide levels in different serum samples and comparing the results with their glucose levels. As both blood glucose and sulfide levels can serve as indicators of certain health conditions, such as diabetes or sulfur metabolism disorders, this comparison provides valuable insights. Importantly, no complicated sample pretreatment was involved, thus this method can be easily adopted as a point-of-care diagnostic device. Additionally, the study also revealed a higher concentration of sulfide in cancer cells than in normal cells, offering a new development direction for differentiating between cancer cells and normal cells.

Effects of static magnetic field on the sulfate metabolic pathway involved in Magnetospirillum magneticum AMB-1 cell growth and magnetosome formation.

Magnetotactic bacteria (MTB) can use their unique intracellular magnetosome organelles to swim along the Earth's magnetic field. They play important roles in the biogeochemical cycles of iron and sulfur. Previous studies have shown that the applied magnetic fields could affect the magnetosome formation and antioxidant defense systems in MTB. However, the molecular mechanisms by which magnetic fields affect MTB cells remain unclear. We aim to better understand the dark at 28°C-29°C for 20 h, as shownthe interactions between magnetic fields and cells, and the mechanism of MTB adaptation to magnetic field at molecular levels. We performed microbiological, transcriptomic, and genetic experiments to analyze the effects of a weak static magnetic field (SMF) exposure on the cell growth and magnetosome formation in the MTB strain Magnetospirillum magneticum AMB-1. The results showed that a 1.5 mT SMF significantly promoted the cell growth but reduced magnetosome formation in AMB-1, compared to the geomagnetic field. Transcriptomic analysis revealed decreased expression of genes primarily involved in the sulfate reduction pathway. Consistently, knockout mutant lacking adenylyl-sulfate kinase CysC did no more react to the SMF and the differences in growth and Cmag disappeared. Together with experimental findings of increased reactive oxidative species in the SMF-treated wild-type strain, we proposed that cysC, as a key gene, can participate in the cell growth and mineralization in AMB-1 by SMF regulation. This study suggests that the magnetic field exposure can trigger a bacterial oxidative stress response involved in AMB-1 growth and magnetosome mineralization by regulating the sulfur metabolism pathway. CysC may serve as a pivotal enzyme in mediating sulfur metabolism to synchronize the impact of SMF on both growth and magnetization of AMB-1.

Sulfur Metabolism in Thiocapsa bogorovii BBS and the Role of HydSL Hydrogenase

Sulfur Metabolism in Thiocapsa bogorovii BBS and the Role of HydSL Hydrogenase

Insights into the spatial distributions of bacteria, archaea, ammonia-oxidizing bacteria and archaea communities in sediments of Daya Bay, northern South China Sea

Microbe plays an important role in the biogeochemical cycles of the coastal waters. However, comprehensive information about the microbe in the gulf waters is lacking. This study employed high-throughput sequencing and quantitative PCR (qPCR) to investigate the distribution patterns of bacterial, archaeal, ammonia-oxidizing bacterial (AOB), and archaeal (AOA) communities in Daya Bay. Community compositions and principal coordinates analysis (PCoA) exhibited significant spatial characteristics in the diversity and distributions of bacteria, archaea, AOB, and AOA. Notably, various microbial taxa (bacterial, archaeal, AOB, and AOA) exhibited significant differences in different regions, playing crucial roles in nitrogen, sulfur metabolism, and organic carbon mineralization. Canonical correlation analysis (CCA) or redundancy analysis (RDA) indicated that environmental parameters such as temperature, salinity, nitrate, total nitrogen, silicate, and phosphate strongly influenced the distributions of bacterial, archaeal, AOB, and AOA. This study deepens the understanding of the composition and ecological function of prokaryotes in the bay.

Genome-Wide Identification of Selenium-Responsive MicroRNAs in Tea Plant (Camellia sinensis L. O. Kuntze)

Anadequate selenium (Se) intake can enhance human immunity and prevent diseases development. About one billion people in the world have varying degrees of Se deficiency in the world. Organic Se from tea infusion is the most easily absorbed and utilized Se form by the human body. Therefore the production of tea plants rich in Se is an effective way to increase Se dietary intake, but there are few studies on the involvement and functions of miRNAs in the responses of tea plants after Se treatment. MicroRNAs (miRNAs) are endogenous (non-coding) single-stranded RNAs that play crucial roles in regulating plant nutrient element acquisition and accumulation. Physiological analysis discovered that the total Se content in tea plant roots markedly increased under 0.05 mmol·L−1 selenite treatment, with no toxicity symptoms in the leaves and roots. To screen the miRNAs responsive to Se treatment in tea plants, miRNA libraries were constructed from the tea cultivar “Echa 1”. Using high-throughput sequencing, 455 known miRNAs and 203 novel miRNAs were identified in this study. In total, 13 miRNAs were selected that were differentially expressed in tea plants’ roots under 0.05 mmol·L−1 selenite treatments. Gene Ontology enrichment analysis revealed that the target genes of the differentially expressed miRNAs mainly belonged to the metabolic process, membrane, and catalytic activity ontologies. Kyoto Encyclopedia of Genes and Genomes pathway enrichment analysis suggested that beta-alanine, taurine, hypotaurine, and sulfur metabolism were the most enriched pathways among the differentially expressed miRNAs, implying their involvement in Se accumulation and tolerance in tea plants. Further characterization of the data revealed that the number of novel miRNAs was comparable to that of known miRNAs, indicating that novel miRNAs significantly contributed to the regulation of Se accumulation in tea plant roots. Thisstudy lays the foundation for further research on the regulatory mechanisms underlying Se accumulation and tolerance in tea plants, providing targets to molecular breeding strategies for improving tea nutritional properties.

Using sulfur stable isotope ratios (δ34 S) for animal geolocation: Estimating the delay mechanisms between diet ingestion and isotope incorporation in tail hair.

Metabolism and diet quality play an important role in determining delay mechanisms between an animal ingesting an element and depositing the associated isotope signal in tissue. While many isotope mixing models assume instantaneous reflection of diet in an animal- tissue, this is rarely the case. Here we use data from wildebeest to measure the lag time between ingestion of 34 S and its detection in tail hair. We use time-lagged regression analysis of δ34 S data from GPS-collared blue wildebeest from the Serengeti ecosystem in combination with δ34 S isoscape data to estimate the lag time between an animal ingesting and depositing 34 S in tail hair. The best fitting regression model of δ34 S in tail hair and an individual- position on the δ34 S isoscape is generated assuming an average time delay of 78 days between ingestion and detection in tail hair. This suggests that sulfur may undergo multiple metabolic transitions before being deposited in tissue. Our findings help to unravel the underlying complexities associated with sulfur metabolism and are broadly consistent with results from other species. These findings will help to inform research aiming to apply the variation of δ34 S in inert biological material for geolocation or understanding dietary changes, especially for fast moving migratory ungulates such as wildebeest.

Sulfinamide Formation from the Reaction of Bacillithiol and Nitroxyl.

Bacillithiol (BSH) replaces glutathione (GSH) as the most prominent low-molecular-weight thiol in many low G + C gram-positive bacteria. BSH plays roles in metal binding, protein/enzyme regulation, detoxification, redox buffering, and bacterial virulence. Given the small amounts of BSH isolated from natural sources and relatively lengthy chemical syntheses, the reactions of BSH with pertinent reactive oxygen, nitrogen, and sulfur species remain largely unexplored. We prepared BSH and exposed it to nitroxyl (HNO), a reactive nitrogen species that influences bacterial sulfur metabolism. The profile of this reaction was distinct from HNO oxidation of GSH, which yielded mixtures of disulfide and sulfinamide. The reaction of BSH and HNO (generated from Angeli's salt) gives only sulfinamide products, including a newly proposed cyclic sulfinamide. Treatment of a glucosamine-cysteine conjugate, which lacks the malic acid group, with HNO forms disulfide, implicating the malic acid group in sulfinamide formation. This finding supports a mechanism involving the formation of an N-hydroxysulfenamide intermediate that dehydrates to a sulfenium ion that can be trapped by water or internally trapped by an amide nitrogen to give the cyclic sulfinamide. The biological relevance of BSH reactivity toward HNO is provided through in vivo experiments demonstrating that Bacillus subtilis exposed to HNO shows a growth phenotype, and a strain unable to produce BSH shows hypersensitivity toward HNO in minimal medium cultures. Thiol analysis of HNO-exposed cultures shows an overall decrease in reduced BSH levels, which is not accompanied by increased levels of BSSB, supporting a model involving the formation of an oxidized sulfinamide derivative, identified in vivo by high-pressure liquid chromatography/mass spectrometry. Collectively, these findings reveal the unique chemistry and biology of HNO with BSH in bacteria that produce this biothiol.

Chlorella pyrenoidosa as a potential bioremediator: Its tolerance and molecular responses to cadmium and lead

Heavy metal contamination negatively affects plants and animals in water as well as soils. Some microalgae can remove heavy metal contaminants from wastewater. The aim of this study was to screen green microalgae (GM) to identify those that tolerate high concentrations of toxic heavy metals in water as possible candidates for phytoremediation. Analyses of the tolerance, physiological parameters, ultrastructure, and transcriptomes of GM under Cd/Pb treatments were conducted. Compared with the other GM, Chlorella pyrenoidosa showed stronger tolerance to high concentrations of Cd/Pb. The reduced glutathione content and peroxidase activity were higher in C. pyrenoidosa than those in the other GM. Ultrastructural observations showed that, compared with other GM, C. pyrenoidosa had less damage to the cell surface and interior under Cd/Pb toxicity. Transcriptome analyses indicated that the “peroxisome” and “sulfur metabolism” pathways were enriched with differentially expressed genes under Cd/Pb treatments, and that CpSAT, CpSBP, CpKAT2, Cp2HPCL, CpACOX, CpACOX2, and CpACOX4, all of which encode antioxidant enzymes, were up-regulated under Cd/Pb treatments. These results show that C. pyrenoidosa has potential applications in the remediation of polluted water, and indicate that antioxidant enzymes contribute to Cd/Pb detoxification. These findings will be useful for producing algal strains for the purpose of bioremediation in water contamination.

The Microbiome in Quiescent Crohn’s Disease With Persistent Symptoms Show Disruptions in Microbial Sulfur and Tryptophan Pathways

Even in the absence of inflammation, persistent symptoms in Crohn's disease (CD) are prevalent and worsen quality of life. Amongst patients without inflammation (quiescent CD), we hypothesized that microbial community structure and function, including tryptophan metabolism, would differ between patients with persistent symptoms (qCD+ S) and without persistent symptoms (qCD-S). We performed a multicenter observational study nested within the Study of a Prospective Adult Research Cohort with Inflammatory Bowel Disease. Quiescent inflammation was defined by fecal calprotectin level <150 mcg/g. Persistent symptoms were defined by Crohn's Disease Patient-Reported Outcome-2. Active CD, diarrhea-predominant irritable bowel syndrome, and healthy controls were included as controls. Stool samples underwent whole-genome shotgun metagenomic sequencing. Thirty-nine patients with qCD+ S, 274 qCD-S, 21 active CD, 40 diarrhea-predominant irritable bowel syndrome, and 50 healthy controls were included for analysis. Patients with qCD+ S had a less-diverse microbiome. Furthermore, patients with qCD+ S showed significant enrichment of bacterial species that are normal inhabitants of the oral microbiome (eg Rothia dentocariosa, Fusobacterium nucleatum) and sulfidogenic microbes (eg Prevotella copri, Bilophila spp.). Depletion of important butyrate and indole producers (eg Eubacterium rectale, Faecalibacterium prausnitzii) was also noted in qCD+ S. Potential metagenome-related functional changes in cysteine and methionine metabolism, ATP transport, and redox reactions were disturbed in qCD+ S, also suggestive of altered sulfur metabolism. Finally, qCD+ S showed significant reductions in bacterial tnaA genes, which mediate tryptophan metabolism to indole, and significant tnaA allelic variation compared with qCD-S. The microbiome in qCD+ S showed significant differences in sulfidogenesis, butyrate producers, and typically oral microbes compared to qCD-S and active CD. These results suggest that inflammation may lead to durable microbiome alterations which may mediate persistent symptoms through testable mechanisms.

Gene identification and transcriptome analysis of cadmium stress in tomato

Cadmium (Cd) is a highly toxic heavy metal that can severely hinder plant growth and development. Tomato is one of the most important economical crops in the world, and its quality and safety are closely related to human health. Therefore, it is important to elucidate the molecular mechanisms involved in tomato plant responses to Cd stress. In this study, tomato plants were treated with or without 100 μM Cd2+ in hydroponic culture for 3 days. Transcriptional changes in tomato roots and shoots were examined by transcriptome sequencing techniques. A total of 1,123 differentially expressed genes (DEGs) were identified in roots and 159 DEGs were identified in shoots after Cd treatment, including 15 DEGs were upregulated and 24 DEGs were downregulated in both roots and shoots. KEGG enrichment analysis showed that DEGs in the roots and shoots under Cd stress were significantly enriched in the glutathione metabolism pathway, sulfur metabolism pathway, phenylpropanoid biosynthesis, plant-pathogen interaction cutin pathway, suberine and wax biosynthesis pathway, and photosynthesis-antenna proteins pathway. 15 DEGs were further validated by quantitative real-time RT-PCR, including ABC transporter genes, WRKY transcription factors, and NAC transcription factors, among others. This study will provide a theoretical basis for further research on the molecular mechanisms involved in tomato responses to Cd stress, and genetic improvement of Cd tolerance.

Influence of Lactose Supplementation on Regulation of Streptococcus thermophilus on Gut Microbiota.

It has been found that Streptococcus thermophilus (S. thermophilus) influenced the gut microbiota and host metabolism with strain specificity in C57BL/6J mice in the previous study, though it remains unclear whether lactose as a dietary factor associated with dairy consumption is involved as the mediator in the interaction. In the present study, integrated analysis of 16S rRNA gene sequencing and untargeted metabolomics by liquid chromatography-mass spectrometry of fecal samples in C57BL/6J mice was applied to evaluate the effect of lactose on the regulation of gut microbiota by two S. thermophilus strains (4M6 and DYNDL13-4). The results showed that the influence of lactose supplementation on gut microbiota induced by S. thermophilus ingestion was strain-specific. Although two S. thermophilus strains ingestion introduced similar perturbations in the fecal microbiota and gut microbial metabolism, the regulation of DYNDL13-4 on the gut microbiota and metabolism was more affected by lactose than 4M6. More specifically, lactose and 4M6 supplementation mainly enriched pathways of d-glutamine and d-glutamate metabolism, alanine, aspartate, and glutamate metabolism, and tryptophan and phenylalanine metabolism in the gut, whereas 4M6 only enriched tryptophan and phenylalanine metabolism. DYNDL13-4-L (DYNDL13-4 with lactose) had significant effects on sulfur, taurine, and hypotaurine metabolism in the gut and on phenylalanine, tyrosine, tryptophan biosynthesis, and linoleic acid metabolism in serum relative to the DYNDL13-4. Our study demonstrated the strain-specific effect of lactose and S. thermophilus supplementation on gut microbiota and host metabolism. However, considering the complexity of the gut microbiota, further research is necessary to provide insights to facilitate the design of personalized fermented milk products as a dietary therapeutic strategy for improving host health.

Characterization of Pseudomonas sp. En3, an Endophytic Bacterium from Poplar Leaf Endosphere with Plant Growth-Promoting Properties

Growth-promoting endophytic bacteria possess substantial potential for sustainable agriculture. Here, we isolated an endophytic bacterium, Pseudomonas sp. En3, from the leaf endosphere of Populus tomentosa and demonstrated its significant growth-promoting effects on both poplar and tomato seedlings. The phosphorus solubilization and nitrogen fixation abilities of strain En3 were confirmed via growth experiments on NBRIP and Ashby media, respectively. Salkowski staining and HPLC-MS/MS confirmed that En3 generated indole-3-acetic acid (IAA). The infiltration of En3 into leaf tissues of multiple plants did not induce discernible disease symptoms, and a successful replication of En3 was observed in both poplar and tobacco leaves. Combining Illumina and Nanopore sequencing data, we elucidated that En3 possesses a circular chromosome of 5.35 Mb, exhibiting an average G + C content of 60.45%. The multi-locus sequence analysis (MLSA) and genome average nucleotide identity (ANI) supported that En3 is a novel species of Pseudomonas and constitutes a distinct phylogenetic branch with P. rhizosphaerae and P. coleopterorum. En3 genome annotation analysis revealed the presence of genes associated with nitrogen fixation, phosphate solubilization, sulfur metabolism, siderophore biosynthesis, synthesis of IAA, and ethylene and salicylic acid modulation. The findings suggest that Pseudomonas sp. En3 exhibits significant potential as a biofertilizer for crop and tree cultivation.

Long-term effects of thiosulfate on the competition between sulfur-mediated bacteria and glycogen accumulating organisms in sulfate-rich carbon-deficient wastewater

Sewage nutrient (e.g., nitrogen and phosphorus) biological removal performance is often limited by the deficient carbon source and undesirable glycogen accumulating organisms (GAOs), even in sulfate-containing wastewater. Thiosulfate (S2O32−) as a bioavailable, environmentally-benign, metastable and cost-effective agent has been regarded as electron carriers that induces high sulfur-mediated bacterial activity for nutrient removal from wastewater. In this study, the long-term effects of thiosulfate on the competition between sulfur-mediated bacteria (SMB, including sulfur-reducing bacteria (SRB) and sulfur-oxidizing bacteria (SOB)) and GAOs were explored to further close the gap of our knowledge on the control of GAOs under carbon deficient wastewater. Three reactors were continuously operated for over 100 days and were fed with 200 mg acetate-COD/L and 20 (R1), 50 (R2) and 80 (R3) mg S/L thiosulfate respectively. The results revealed that adding thiosulfate at the beginning of the anoxic phase promoted sulfur metabolism and increased the proliferation of SRB (mainly Desulfobacter) and SOB (mainly Chromatiaceae). Correspondingly, the relative abundance of GAOs (mainly Candidatus_Competibacter) decreased. After the carbon source was reduced, the abundance of GAOs increased and the competitive activity of SRB was weakened, resulting in the reduced sulfate reduction, which could be attributed to the fact that GAOs had a higher carbon source competitiveness than SRB under low carbon source conditions. While SOB maintained a high abundance due to the addition of thiosulfate as an additional electron donor, which enhanced the denitrification efficiency. Additionally, the dominant SOB shifted from Thiobacillus to Chromatiaceae during the long-term operation, indicating that Chromatiaceae had a higher competitive advantage for reduced sulfur (e.g., S2O32−, Polysulfide (Poly-S)) and nitrate compared to Thiobacillus. Furthermore, microbial functional genes revealed that S metabolism was enhanced during long-term operation. The potential mechanism and optimization strategy regarding the competition between sulfur-mediated bacteria and GAOs were revealed.

Genotypes of Eruca vesicaria subsp. sativa grown in contrasting field environments differ on transcriptomic and metabolomic levels, significantly impacting nutritional quality.

Rocket (Eruca vesicaria subsp. sativa) is a source of sulfur-containing glucosinolates (GSLs). GSLs and their breakdown hydrolysis products (GHPs) are responsible for health-related benefits, such as anti-cancer and anti-neurodegenerative properties. Understanding how phytochemical composition changes between cultivation environments is key to developing cultivars with improved nutritional quality. Two consecutive harvests (first and second regrowth) of crops, grown in both Italy and the UK, were used to determine the phytochemical and transcriptomic differences between six lines of Eruca. Samples were taken upon delivery from field sites (D0) and after five days of cold storage (D5) for each location. Leaves were analysed for sulfur content, volatile organic compounds (VOCs), GSLs, GHPs, and sugars. Transcriptome data were associated with metabolite profiles to identify differentially expressed genes between plants grown in the two environments. VOC compounds (carbon disulfide, methyl thiocyanate) were associated with growth environment and with differences in sulfur metabolism gene expression (APR2, LSU2, LSU3, SDI1, SiR), GSL biosynthesis (MYB28, FMOGS-OX2) and GHP formation (ESM1, TGG1, TGG2). The concentrations of sugars were an order of magnitude greater in UK grown samples (up to 29.9 mg g-1 dry weight; dw). Sulfur content was significantly higher in the Italy plant samples (11.4 - 20.1 mg g-1 dw), which was in turn associated with higher concentrations of GSLs (pentyl GSL, up to 15.8 μmol g-1 dw; sinigrin, up to 0.005 μmol g-1 dw; glucoraphanin, up to 5.1 μmol g-1 dw; glucorucolamine, up to 23.6 μmol g-1 dw; neoglucobrassicin, up to 5.3 μmol g-1 dw) and hydrolysis products (sativin, up to 13.5 μmol g-1 dw; erucin, up to 1 μmol g-1 dw; sulforaphane, up to 34.7 μmol g-1 dw). VOC profiles of plants cultivated in the UK were distinct from Italy grown plants, with higher relative abundances of alkanes and esters in second cut and shelf-life (D5) samples. The data indicate a significant interaction of cultivar response with environment, highlighting the difficulty of producing Eruca crops with consistent phytochemical and postharvest traits. Genes with differential expression between plants grown in Italy and the UK could be used as markers of phytochemical quality and composition.

Limitation of amino acid availability by bacterial populations during enhanced colitis in IBD mouse model.

Inflammatory bowel disease is associated with an increase in Enterobacteriaceae and Enterococcus species; however, the specific mechanisms are unclear. Previous research has reported the associations between microbiota and inflammation, here we investigate potential pathways that specific bacteria populations use to drive gut inflammation. Richie et al. show that these bacterial populations utilize an alternate sulfur metabolism and are tolerant of host-derived immune-response products. These metabolic pathways drive host gut inflammation and fuel over colonization of these pathobionts in the dysbiotic colon. Cultured isolates from dysbiotic mice indicated faster growth supplemented with L-cysteine, showing these microbes can utilize essential host nutrients.

Biological Effects and Mechanisms of Taurine in Various Therapeutics.

More than two hundred years ago, taurine was first isolated from materials derived from animals. It is abundantly found in a wide range of mammalian and non-mammalian tissues and diverse environments. Taurine was discovered to be a by-product of the metabolism of sulfur only a little over a century and a half ago. Recently, there has been a renewed academic interest in researching and exploring various uses of the amino acid taurine, and recent research has indicated that it may be useful in the treatment of a variety of disorders, including seizures, high blood pressure, cardiac infarction, neurodegeneration, and diabetes. Taurine is currently authorised for the therapy of congestive heart failure in Japan, and it has shown promising results in the management of several other illnesses as well. Moreover, it was found to be effective in some clinical trials, and hence it was patented for the same. This review compiles the research data that supports the prospective usage of taurine as an antibacterial, antioxidant, anti-inflammatory, diabetic, retinal protective, and membrane stabilizing agent, amongst other applications.

Simultaneous selenite reduction and nitrogen removal using Paracoccus sp.: Reactor performance, microbial community, and mechanism

Selenium-containing wastewater has a high concentration of nitrogen compounds (ammonia nitrogen [NH4+-N]), leading to water pollution. Thus, the simultaneous reduction of selenium and removal of nitrogen compounds during wastewater treatment has become the top priority. However, the exogenous bacteria that can simultaneously reduce selenite and remove ammonia nitrogen and colonize in the wastewater treatment systems have not been reported. Additionally, the effects and the underlying mechanism of biofortification on the reduction and removal efficiency of the microorganisms remain unclear. In this study, we investigated the simultaneous selenite reduction and nitrogen removal efficiency of Paracoccus sp. (strain SSJ) isolated from selenium-contaminated soil and explored biofortification effects on the composition and structure of the microbial community. Using sequencing biofilm batch reactors (SBBRs), the structural and functional characteristics of the microbial community were systematically compared between the control (group A) and biofortified (group B) groups. Strain SSJ could simultaneously reduce 63.28% of selenite and remove 93.05% of NH4+-N within 24 h. Moreover, no accumulation of nitrate nitrogen (NO3−-N) and nitrite nitrogen (NO2−-N) was observed in the reaction process. The performance and stability of the SBBRs enhanced by strain SSJ were greatly improved. Illumina sequencing results showed that strain SSJ was surprisingly colonized, and Paracoccus was the predominant genus in group B (relative abundance: 13.93%). Moreover, PICRUSt2 analysis results suggested that the microbial community in group B demonstrated increased rates of ammonia nitrogen removal through ammonia assimilation and selenite reduction through sulfur metabolism and glutathione-mediated selenite reduction pathway. In summary, our findings shed light on the mechanism for simultaneous selenite reduction and nitrogen removal by biofortification and provide novel microbial resources for the treatment of selenite-containing wastewater.

Long-read genome sequencing provides novel insights into the harmful algal bloom species Prymnesium parvum

Prymnesium parvum is a toxin-producing haptophyte that causes harmful algal blooms worldwide, which are often associated with massive fish-kills and subsequent economic losses. In here, we present nuclear and plastid genome assemblies using PacBio HiFi long reads and DNBseq short reads for the two P. parvum strains UTEX 2797 and CCMP 3037, representing producers of type A prymnesins. Our results show that the P. parvum strains have a moderate haptophyte genome size of 97.56 and 107.32 Mb. The genome assemblies present one of highest contiguous assembled contig sequences to date consisting of 463 and 362 contigs with a contig N50 of 596.99 kb and 968.39 kb for strain UTEX 2797 and CCMP 3037, respectively. The assembled contigs of UTEX 2797 and CCMP 3037 were anchored to 34 scaffolds, with a scaffold N50 of 5.35 Mb and 3.61 Mb, respectively, accounting for 93.2 % and 97.9 % of the total length. Each plastid genome comprises a circular contig. A total of 20,578 and 19,426 protein-coding genes were annotated for UTEX 2797 and CCMP 3037. The expanded gene family analysis showed that starch and sucrose metabolism, sulfur metabolism, energy metabolism and ABC transporters are involved in the evolution of P. parvum. Polyketide synthase (PKS) genes responsible for the production of secondary metabolites such as prymnesins displayed different expression patterns under nutrient limitation. Overlap with repeats and horizontal gene transfer may be two contributing factors to the high number of PKS genes found in this species. The two high quality P. parvum genomes will serve as valuable resources for ecological, genetic, and toxicological studies of haptophytes that can be used to monitor and potentially manage harmful blooms of ichthyotoxic P. parvum in the future.