Stony corals are colonial cnidarians that sustain the most biodiverse marine ecosystems on Earth: coral reefs. Despite their ecological importance, little is known about the cell types and molecular ...pathways that underpin the biology of reef-building corals. Using single-cell RNA sequencing, we define over 40 cell types across the life cycle of Stylophora pistillata. We discover specialized immune cells, and we uncover the developmental gene expression dynamics of calcium-carbonate skeleton formation. By simultaneously measuring the transcriptomes of coral cells and the algae within them, we characterize the metabolic programs involved in symbiosis in both partners. We also trace the evolution of these coral cell specializations by phylogenetic integration of multiple cnidarian cell type atlases. Overall, this study reveals the molecular and cellular basis of stony coral biology.
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•Whole-organism single-cell analysis of the stony coral Stylophora pistillata•Skeleton formation and symbiosis-associated gene expression dynamics•Identification of immune cell programs in Stylophora pistillata•Conserved broad cell type identities across cnidarian lineages
Over 40 cell types across the life cycle of Stylophora pistillata, a stony coral, are identified through the use of single-cell RNA sequencing. From this reference atlas, the molecular pathways underpinning coral reef building, specialized immune cells, and the metabolic programs involved in symbiosis between coral and algae partners are described.
Gold nanoparticles are used in an expanding spectrum of biomedical applications. However, little is known about their long-term fate in the organism as it is generally admitted that the inertness of ...gold nanoparticles prevents their biodegradation. In this work, the biotransformations of gold nanoparticles captured by primary fibroblasts were monitored during up to 6 mo. The combination of electron microscopy imaging and transcriptomics study reveals an unexpected 2-step process of biotransformation. First, there is the degradation of gold nanoparticles, with faster disappearance of the smallest size. This degradation is mediated by NADPH oxidase that produces highly oxidizing reactive oxygen species in the lysosome combined with a cell-protective expression of the nuclear factor, erythroid 2. Second, a gold recrystallization process generates biomineralized nanostructures consisting of 2.5-nm crystalline particles self-assembled into nanoleaves. Metallothioneins are strongly suspected to participate in buildings blocks biomineralization that self-assembles in a process that could be affected by a chelating agent. These degradation products are similar to aurosomes structures revealed 50 y ago in vivo after gold salt therapy. Overall, we bring to light steps in the lifecycle of gold nanoparticles in which cellular pathways are partially shared with ionic gold, revealing a common gold metabolism.
Struvite biomineralization is an ecologically sound technology adepts at the efficient recovery and recycling of phosphorus from wastewater. However, the biomineralization process is often perturbed ...by the presence of antibiotics, notably tetracycline (TC), the impact of which on the biomineralization system has not been elucidated. This study examines the efficacy of Bacillus cereus LB-9 in struvite biomineralization, focusing on the precipitates' composition, morphology, and TC content. LB-9 facilitate an alkaline environment that effectively recovering nitrogen and phosphorus. These findings indicate that TC retards the initial formation of struvite and the concurrent recovery of nitrogen and phosphorus. Nonetheless, at sub-10 mg/L TC concentrations, TC enhanced struvite production (0.38g) by stimulating LB-9's growth and metabolic activity. Conversely, at 10 mg/L TC, the strain's activity was markedly suppressed within the initial four days. This data suggest that TC promotes the strain's proliferation and metabolism, potentially through cellular secretions, thereby augmenting phosphorus recovery from wastewater. Notably, the recovered struvite doesn’t contain TC, aligning with regulatory standards for agricultural application. In summary, LB-9-mediated struvite recovery is an effective strategy for producing phosphorus-enriched fertilizers and mitigating TC contamination, offering significant implications for wastewater treatment and industrial process development, particularly in the context of prevalent TC in wastewater.
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•LB-9 raise NH4+ concentration and pH to favorate struvite biomineralization.•LB-9 catalyzes struvite synthesis, low TC boosting phosphorus recovery by 58%.•Produced struvite is free of TC, presenting a sustainable method for P recovery.
High-precision analysis of the excess abundance (relative to the stochastic distribution) of mass 48 isotopologues in CO2 evolved from acid digestion of carbonates (∆48) has not been possible until ...recently due to the relatively low natural abundance of 18O. Here we show that the 253 Plus™ gas source mass spectrometer equipped with Faraday cups and 1013 Ω resistors can perform combined ∆47 and ∆48 analyses on carbonates with external reproducibilities (1SD) of 0.010 ‰ and 0.030 ‰, respectively.
~10 mg aliquots of five carbonate reference materials (ETH 1, ETH 2, ETH 3, ETH 4, and Carrara) are digested with phosphoric acid at 90 °C using a common acid bath. The evolved CO2 is purified using an automated gas preparation system (including cryotraps and a GC) and analyzed for its ∆47 and ∆48 compositions using the dual inlet system of a 253 Plus™ gas source mass spectrometer. Raw ∆47 and ∆48 values are finally normalized to the Carbon Dioxide Equilibrium Scale (CDES).
In ∆47, CDES 90°Cvs. ∆48, CDES 90°C space, calcite reference materials Carrara, ETH 3 and ETH 4 agree with the equilibrium curve for calcite after adding semi-empirically determined 90 °C acid fractionation factors of 0.196 ‰ (for ∆47) and 0.136 ‰ (for ∆48) to theoretical ∆63 and ∆64 data. Agreement between measured and theoretically expected ∆48, CDES 90°C highlights the accuracy of our high-precision clumped isotope analytical setup. Combined analysis of the abundances of mass 47 and mass 48 isotopologues in CO2 evolved from acid digestion of natural carbonates has excellent potential for the determination of accurate and highly precise paleotemperatures as well as for the identification of rate-limiting kinetic processes involved in biomineralization. A formation temperature of 15(±2) °C is obtained on the 95 % confidence level for the Upper Cretaceous chalk sample ETH 3.
Microbially induced calcium carbonate precipitation (MICCP) is a naturally occurring biological process in which microbes produce inorganic materials as part of their basic metabolic activities. This ...technology has been widely explored and promising with potential in various technical applications. In the present review, the detailed mechanism of production of calcium carbonate biominerals by ureolytic bacteria has been discussed along with role of bacteria and the sectors where these biominerals are being used. The applications of bacterially produced carbonate biominerals for improving the durability of buildings, remediation of environment (water and soil), sequestration of atmospheric CO2 filler material in rubbers and plastics etc. are discussed. The study also sheds light on benefits of bacterial biominerals over traditional agents and also the issues that lie in the path of successful commercialization of the technology of microbially induced calcium carbonate precipitation from lab to field scale.
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•The spines of Heliocidaris crassispina was composed of calcite containing magnesium (approximately 4.8%).•The crude extract from spines converted amorphous calcium carbonate to ...calcite in the presence of high concentrations of magnesium.•HC tropomyosin contributing to calcite formation was determined from spines of Heliocidaris crassispina.•Magnesium-containing calcite was synthesized by recombinant recombinant HC tropomyosin.
Calcium carbonate is present in many biominerals, including in the exoskeletons of crustaceans and shells of mollusks. High Mg-containing calcium carbonate was synthesized by high temperatures, high pressures or high molecular organic matter. For example, biogenic high Mg-containing calcite is synthesized under strictly controlled Mg concentration at ambient temperature and pressure. The spines of sea urchins consist of calcite, which contain a high percentage of magnesium. In this study, we investigated the factors that increase the magnesium content in calcite from the spines of the sea urchin, Heliocidaris crassispina. X-ray diffraction and inductively coupled plasma mass spectrometry analyses showed that sea urchin spines contain about 4.8% Mg. The organic matrix extracted from the H. crassispina spines induced the crystallization of amorphous phase and synthesis of magnesium-containing calcite, while amorphous was synthesized without SUE (sea urchin extract). In addition, aragonite was synthesized by SUE treated with protease-K. HC tropomyosin was specifically incorporated into Mg precipitates. Recombinant HC-tropomyosin induced calcite contained 0.1–2.5% Mg synthesis. Western blotting of sea urchin spine extracts confirmed that HC tropomyosin was present in the purple sea urchin spines at a protein weight ratio of 1.5%. These results show that HC tropomyosin is one factor that increases the magnesium concentration in the calcite of H. crassispina spines.
This work reports the use of ferrioxalate complexes to assist solar photo-Fenton treatment of pentachlorophenol (PCP) in aqueous medium at mild pH, which inhibits the precipitation of iron hydroxides ...and allows working at a low iron dosage. The experimental parameters were optimized by assessing the effect of initial concentrations of H2O2 (0-2.5 mM) and Fe(II) (2-10 mg/L), pH (3.0-9.0) and iron/oxalic acid molar ratios (1:0-1:13.5) on total organic carbon (TOC) removal. Ferrioxalate-assisted solar photo-Fenton achieved 97.5% mineralization in 120 min, clearly outperforming conventional Fenton and solar photo-Fenton. The presence of photosensitive ferrioxalate complexes accounted for the enhancement, as a result of Fe(II) regeneration that accelerated the hydroxyl radical (OH) production. The time course of H2O2 and Fe(II) concentrations was evaluated under different iron/oxalic acid ratios. The five carboxylic acids determined by ion-exclusion HPLC and the eight aromatic by-products identified by GC-MS allowed the proposal of a degradation pathway that included hydroxylation, dechlorination and dimerization steps. Complete chloride ion release was achieved after 90 min of treatment.
To investigate the transdentinal effects of surface reaction-type pre-reacted glass-ionomer (S-PRG) fillers on odontoblast-like cells.
An eluate of S-PRG fillers was obtained by dissolving the ...particles in distilled water (1:1 m/v). Dentin discs with similar permeability were mounted into artificial pulp chambers and MDPC-23 cells were seeded on their pulpal surface. The occlusal surface was treated with (n = 10): ultrapure water (negative control – NC), hydrogen peroxide (positive control – PC), S-PRG eluate exposure for 1 min (S-PRG 1 min), or S-PRG filler eluate exposure for 30 min (S-PRG 30 min). After 24 h, cell viability (alamarBlue) and morphology (SEM) were evaluated. The extract obtained from transdentinal diffusion was applied to MDPC-23 pre-cultured in plates for another 24 h to evaluate viability (alamarBlue, 1, 3, and 7 days), gene expression of Col1a1, Alpl, Dspp, and Dmp1 (RT-qPCR, 1 and 7 days), and mineralization (Alizarin Red, 7 days). Data were analyzed with ANOVA (α = 5 %).
While S-PRG 1 min did not differ from NC, S-PRG 30 min reduced 17.9 % viability of cells from discs. S-PRG treatments resulted in low cell detaching from dentin, and the remaining cells exhibited typical morphology or minor cytoplasmic contraction. S-PRG 30 min slightly increased cell viability (6 %) 1 day after contact with the extract. S-PRG treatments upregulated the expression of the investigated genes, especially after 1 day. S-PRG 30 min stimulated mineralization activity by 39.7 %.
S-PRG filler eluate does not cause transdentinal cytotoxicity on odontoblast-like cells, and long-term exposure can stimulate their dentinogenic-related mineralization activity.
The transdentinal elution of ions from S-PRG fillers is not expected to be harmful to the dental pulp and may exert bioactive effects by inducing dentin matrix deposition through the metabolism of underlying odontoblasts.
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•Green decontamination tool was created to eliminate predators cidal to H. pluvialis.•CBDS was conducted at mild alkalinity and low CaCl2 for non-calcifying H. pluvialis.•CBDS showed ...an efficient removal of algicidal bacteria and fungi during cultivation.•Astaxanthin production using CBDS was significantly enhanced in H. pluvialis.•Large-scale outdoor astaxanthin production in H. pluvialis was improved by CBDS.
Currently, there is a lack of an efficient, environmentally-benign and sustainable industrial decontamination strategy to steadily achieve improved astaxanthin production from Haematococcus pluvialis under large-scale outdoor conditions. Here, this study demonstrates for the first time that a CaCO3 biomineralization-based decontamination strategy (CBDS) is highly efficient in selectively eliminating algicidal microorganisms, such as bacteria and fungi, during large-scale H. pluvialis cultivation under autotrophic and mixotrophic conditions, thereby augmenting the astaxanthin productivity. Under outdoor AT and MT conditions, the average astaxanthin productivity of H. pluvialis using CBDS in a closed photobioreactor system was substantially increased by 14.85- (1.19 mg L−1 d−1) and 13.65-fold (2.43 mg L−1 d−1), respectively, compared to the contaminated H. pluvialis cultures. Given the exponentially increasing demand of astaxanthin, a natural anti-viral, anti-inflammatory, and antioxidant drug, CBDS will be a technology of interest in H. pluvialis-based commercial astaxanthin production which has been hindered by the serious biological contaminations.
Bioavailable calcium is maintained by some crustaceans, in particular freshwater crayfish, by stabilizing amorphous calcium carbonate (ACC) within reservoir organs—gastroliths, readily providing the ...Ca 2+ needed to build a new exoskeleton. Despite the key scientific and biomedical importance of the in situ molecular-level picture of biogenic ACC and its stabilization in a bioavailable form, its description has eluded efforts to date. Herein, using multinuclear NMR, we accomplish in situ molecular-level characterization of ACC within intact gastroliths of the crayfish Cherax quadricarinatus . In addition to the known CaCO 3 , chitin scaffold and inorganic phosphate (Pi), we identify within the gastrolith two primary metabolites, citrate and phosphoenolpyruvate (PEP) and quantify their abundance by applying solution NMR techniques to the gastrolith “soluble matrix.” The long-standing question on the physico-chemical state of ACC stabilizing, P-bearing moieties within the gastrolith is answered directly by the application of solid state rotational-echo double-resonance (REDOR) and transferred-echo double-resonance (TEDOR) NMR to the intact gastroliths: Pi and PEP are found molecularly dispersed throughout the ACC as a solid solution. Citrate carboxylates are found < 5 Å from a phosphate (intermolecular C⋯P distance), an interaction that must be mediated by Ca 2+ . The high abundance and extensive interactions of these molecules with the ACC matrix identify them as the central constituents stabilizing the bioavailable form of calcium. This study further emphasizes that it is imperative to characterize the intact biogenic CaCO 3 . Solid state NMR spectroscopy is shown to be a robust and accessible means of determining composition, internal structure, and molecular functionality in situ.
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