Effects of Fe(II) on anammox community activity and functional genes expression
Ontology highlight
ABSTRACT: Four Fe(II) concentrations (0.03, 0.09, 0.12 & 0.75 mM) were tested to investigate the stimulation and inhibition effects of ferrous iron on anammox bacterial activity. RNAs were extracted from the cultures, and the synthesized cDNAs by reverse transcription were used to carry out GeoChip analysis, by which the functional communities and expression level differences in functional genes under different Fe(II) concentrations conditions were obtained, and the response of anammox bacteria to Fe(II) stimulation and inhibition are speculated.
Project description:Ascorbic acid has been reported to stimulate DNA iterative oxidase TET enzymes, Jumonji C-domain-containinghistone demethylase and potentially RNA m6A demethylase FTO and ALKBH5 as a cofactor. Although ascorbic acid has been widely investigated in reprogramming DNA and histone methylation status in vitro, in cell lines and mouse models, its specific role in the catalytic cycle of dioxygenases remains enigmatic. Here we systematically investigated the stimulation of ascorbic towards TET2, ALKBH3, histone demethylases and FTO. We find that ascorbic acid reprograms epitranscrip-tome by erasing the hypermethylated m6A sites. Biochemistry and Electron spin resonance (ESR) assays demonstrate that ascorbic acid enters the active pocket of dioxygenases, reduces Fe (III), either incorporated upon protein synthesis or generated upon rebounding the hydroxyl radical during oxidation, into Fe (II). Finally, we propose a new model for the catalytic cycle of dioxygenases by adding in the essential dynamic cofactor, ascorbic acid. Ascorbic acid refreshes and regenerates inactive dioxygenase through recycling Fe (III) into Fe (II) in a dynamic “hit-and-run” manner.
Project description:Ascorbic acid has been reported to stimulate DNA iterative oxidase TET enzymes, Jumonji C-domain-containinghistone demethylase and potentially RNA m6A demethylase FTO and ALKBH5 as a cofactor. Although ascorbic acid has been widely investigated in reprogramming DNA and histone methylation status in vitro, in cell lines and mouse models, its specific role in the catalytic cycle of dioxygenases remains enigmatic. Here we systematically investigated the stimulation of ascorbic towards TET2, ALKBH3, histone demethylases and FTO. We find that ascorbic acid reprograms epitranscrip-tome by erasing the hypermethylated m6A sites. Biochemistry and Electron spin resonance (ESR) assays demonstrate that ascorbic acid enters the active pocket of dioxygenases, reduces Fe (III), either incorporated upon protein synthesis or generated upon rebounding the hydroxyl radical during oxidation, into Fe (II). Finally, we propose a new model for the catalytic cycle of dioxygenases by adding in the essential dynamic cofactor, ascorbic acid. Ascorbic acid refreshes and regenerates inactive dioxygenase through recycling Fe (III) into Fe (II) in a dynamic “hit-and-run” manner.
Project description:Before and after anaerobic Fe(II) shocked WT and M-bM-^HM-^FbqsR of late stationary phase P. aeruginosa PA14 strains Associated publication: Kreamer NN, Costa F, Newman DK. 2015. The ferrous iron-responsive BqsRS two-component system activates genes that promote cationic stress tolerance. mBio 6(1):e02549-14. doi:10.1128/mBio.02549-14. Expression profiles of rRNA-depleted total RNA from WT and M-bM-^HM-^FbqsR Fe(II)-shocked (before and after 30 min incubation with 200 M-BM-5M ferrous ammonium sulfate ) cultures grown anaerobically to deep stationary phase (A500 = 0.8) in Fe-limited (1 M-BM-5M ferrous ammonium sulfate) MOPS minimal medium containing succinate as the carbon source, in triplicate
Project description:Several phytohormones and other small molecules have been demonstrated to be involved in iron (Fe) homeostasis. However, how salicylic acid (SA), an essential hormone in plant immunity and defense responses, participates in Fe-deficiency responses in plants is largely unknown. Here, we took advantage of a SA biosynthesis defect mutant phytoalexin deficient 4 (pad4: T-DNA Salk_089936) to explore the possible effects of endogenous SA on the morphological and physiological responses to Fe deprivation. Under a Fe-deficiency treatment, Col-0 showed more severe leaf chlorosis and root growth inhibition compared with the pad4 mutant. The soluble Fe concentrations were significant higher in pad4 than Col-0 under the Fe-deficiency treatment, suggesting that a mutation in the PAD4 gene may alleviate the Fe-deficiency-induced symptoms by regulating the soluble Fe concentrations. Furthermore, a SA signaling maker line (PR1promoter: GUS) was used to investigate how Fe deficiency affects endogenous SA biosynthesis and metabolism. The data showed that Fe deficiency significantly induced SA accumulation in Col-0, and the loss function of PAD4 blocked this process. The requirement of endogenous SA accumulation for Fe-deficiency responses was confirmed using a series of SA biosynthetic mutants and transgenic lines.
Project description:This Phase I clinical trial aims to evaluate the safety, tolerability, pharmacokinetics (PK) profile and preliminary efficacy of intratumoral injection of Carbon Nanoparticle-Loaded Iron [CNSI-Fe(II)] in patients with advanced solid tumors. The study also aims to observe dose-limiting toxicities (DLT) of CNSI-Fe(II) to determine the maximum tolerated dose (MTD) or the highest injectable dose in humans, providing dosing guidelines for future clinical studies. CNSI-Fe(II) shows promise as an innovative tumor therapeutic agent due to its unique properties of ferroptosis. The study primarily focuses on assessing the potential efficacy of CNSI-Fe(II) in patients with advanced solid tumors, particularly in patients with Kras mutation, e.g., pancreatic cancer patients.
Project description:We reported the flg22-triggered immune responses in roots affect the iron deficiency responses and may link to the function of FLS2 and IMA1 in the root. To identify the underlying mechanism of how the root transcriptome profiles respond to +Fe, +Fe+flg22, -Fe, -Fe+flg22 respectively, and if the flg22 responses is dependent on the function of FLS2 and IMA1 in the root, we performed an mRNA-seq experiments in Col-0, fls2 and UBQ10::mCitrine-IMA1 with different treatments. The differentially expressed genes in response to +Fe, +Fe+flg22, -Fe, -Fe+flg22 were analyzed. It has 36 samples in total, with 3 biogical replicates for each condition and each genotype.
Project description:Iron (Fe) is an essential element to plants, but can be harmful if accumulated to toxic concentrations. Fe toxicity can be a major nutritional disorder in rice (Oryza sativa) when cultivated under waterlogged conditions, as a result of excessive Fe solubilization of in the soil. However, little is known about the basis of Fe toxicity and tolerance at both physiological and molecular level. Here we aim at understand the genotypic differences in two rice cultivars with contrasting phenotypes under Fe toxicity.
Project description:au13-06_fit - Fe-FIT-Diff - FIT (FER-LIKE IRON DEFICIENCY-INDUCED TRANSCRIPTION FACTOR) is a regulator of Fe deficiency responses in the root. FIT is a basic helix-loop-helix protein. Here, we investigated the transcriptome changes in response to Fe deficiency (- Fe) versus the control condition (+ Fe) in wild type, the fit-3 loss of function mutant and in FIT overexpression plants.
2015-02-14 | GSE65934 | GEO
Project description:the stimulation effects of natural minerals on denitrification under elevated Fe(II) concentrations
Project description:Before and after anaerobic Fe(II) shocked WT and ∆bqsR of late stationary phase P. aeruginosa PA14 strains Associated publication: Kreamer NN, Costa F, Newman DK. 2015. The ferrous iron-responsive BqsRS two-component system activates genes that promote cationic stress tolerance. mBio 6(1):e02549-14. doi:10.1128/mBio.02549-14.