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The Science of the Total Environment Sep 2024Acephate is commonly used as a seed treatment (ST) in precision agriculture, but its impact on pollinators, earthworms, and soil microorganisms remains unclear. This...
Acephate is commonly used as a seed treatment (ST) in precision agriculture, but its impact on pollinators, earthworms, and soil microorganisms remains unclear. This study aimed to compare the fate of acephate seed dressing (SD) and seed coating (SC) treatments and assess potential risks to bees, earthworms, and soil microorganisms. Additionally, a follow-up study on maize seeds treated with acephate in a greenhouse was conducted to evaluate the maize growth process and the dissipation dynamics of the insecticide. The results indicated that acephate SC led to greater uptake and translocation in maize plants, resulting in lower residue levels in the soil. However, high concentrations of acephate metabolites in the soil had a negative impact on the body weight of earthworms, whereas acephate itself did not. The potential risk to bees from exposure to acephate ST was determined to be low, but dose-dependent effects were observed. Furthermore, acephate ST had no significant effect on soil bacterial community diversity and abundance compared to a control. This study provides valuable insights into the uptake and translocation of acephate SD and SC, and indicates that SC is safer than SD in terms of adverse effects on bees and nontarget soil organisms.
Topics: Zea mays; Animals; Oligochaeta; Bees; Seeds; Soil Microbiology; Agriculture; Insecticides; Phosphoramides; Soil Pollutants; Organothiophosphorus Compounds; Soil
PubMed: 38851355
DOI: 10.1016/j.scitotenv.2024.173761 -
Nature Communications Jun 2024Chloroxylenol is a worldwide commonly used disinfectant. The massive consumption and relatively high chemical stability of chloroxylenol have caused eco-toxicological...
Chloroxylenol is a worldwide commonly used disinfectant. The massive consumption and relatively high chemical stability of chloroxylenol have caused eco-toxicological threats in receiving waters. We noticed that chloroxylenol has a chemical structure similar to numerous halo-phenolic disinfection byproducts. Solar detoxification of some halo-phenolic disinfection byproducts intrigued us to select a rapidly degradable chloroxylenol alternative from them. In investigating antimicrobial activities of disinfection byproducts, we found that 2,6-dichlorobenzoquinone was 9.0-22 times more efficient than chloroxylenol in inactivating the tested bacteria, fungi and viruses. Also, the developmental toxicity of 2,6-dichlorobenzoquinone to marine polychaete embryos decreased rapidly due to its rapid degradation via hydrolysis in receiving seawater, even without sunlight. Our work shows that 2,6-dichlorobenzoquinone is a promising disinfectant that well addresses human biosecurity and environmental sustainability. More importantly, our work may enlighten scientists to exploit the slightly alkaline nature of seawater and develop other industrial products that can degrade rapidly via hydrolysis in seawater.
Topics: Disinfectants; Disinfection; Seawater; Animals; Hydrolysis; Polychaeta; Fungi; Bacteria; Chlorophenols; Viruses; Humans; Xylenes
PubMed: 38849332
DOI: 10.1038/s41467-024-48752-w -
Environmental Science and Pollution... Jun 2024More evidence shows that bioaccessibility instead of total concentrations based on exhaustive extraction methods can better reflect the actual risk level of petroleum...
More evidence shows that bioaccessibility instead of total concentrations based on exhaustive extraction methods can better reflect the actual risk level of petroleum hydrocarbon contaminated sites, so it is essential to establish an effective assessment method for bioaccessibility. This study utilized Tenax extraction, butanol extraction, hydroxypropyl-β-cyclodextrin (HPCD) extraction, and a composite extraction method involving HPCD with LMWOAs (citric acid, CA) and surfactants (rhamnolipid, RL; Tween80, TW80; sodium dodecyl sulfate, SDS) at varying concentrations. These methods were employed to predict the bioaccessibility of earthworms to soil at different aging time of petroleum hydrocarbons. The results showed that traditional extraction methods such as Tenax 6h extraction and n-butanol extraction were ineffective in evaluating petroleum hydrocarbons' bioaccessibility. In contrast, the composite extraction of HPCD and solubilizer enhanced the extraction efficiency of HPCD greatly, and the extraction results showed a significant positive correlation with earthworm accumulation. By the comparison of the extraction results of different fractions of petroleum hydrocarbons, heavy fractions of petroleum hydrocarbons (C-C) are essential factors affecting chemical extraction effects. The correlation coefficients of four composite extraction methods and total petroleum hydrocarbons (TPH) of earthworm accumulation by linear regression analysis ranged from 1.1797 to 1.7990, and the slopes ranged from 0.8727 to 0.9792. Among them, the combined extraction method of 50 mmol/L HPCD and 0.5 mmol/L rhamnolipid had the best effect (r = 0.9792, slope = 1.1797), which could be used as an evaluation method suitable for the bioaccessibility of petroleum hydrocarbons in soil. This study could provide a new method for evaluating the bioaccessibility of organic pollutants and technically supporting risk assessment and bioremediation of complex petroleum hydrocarbons in soil.
Topics: Petroleum; Soil Pollutants; Oligochaeta; Hydrocarbons; Soil; Animals; Surface-Active Agents
PubMed: 38847953
DOI: 10.1007/s11356-024-33683-2 -
Microbiology Spectrum Jul 2024Similarly to other strict blood feeders, leeches from the genus (Hirudinida: Glossiphoniidae) have established a symbiotic association with bacteria harbored...
UNLABELLED
Similarly to other strict blood feeders, leeches from the genus (Hirudinida: Glossiphoniidae) have established a symbiotic association with bacteria harbored intracellularly in esophageal bacteriomes. Previous genome sequence analyses of these endosymbionts revealed co-divergence with their hosts, a strong genome reduction, and a simplified metabolism largely dedicated to the production of B vitamins, which are nutrients lacking from a blood diet. ' Providencia siddallii' has been identified as the obligate nutritional endosymbiont of a monophyletic clade of Mexican and South American spp. However, the genus includes a sister clade of congeners from Central and South America, where the presence or absence of the aforementioned symbiont taxon remains unknown. In this work, we report on a novel bacterial endosymbiont found in a representative from this clade. We found that this symbiont lineage has evolved from within the genus, known mainly from clinical but also environmental strains. Similarly to . , the -associated symbiont displays clear signs of genome reduction, accompanied by an A+T-biased sequence composition. Genomic analysis of its metabolic potential revealed a retention of pathways related to B vitamin biosynthesis, supporting its role as a nutritional endosymbiont. Finally, comparative genomics of both symbiont lineages suggests that an ancient symbiont was likely replaced by the novel one, thus constituting the first reported case of nutritional symbiont replacement in a leech without morphological changes in the bacteriome.
IMPORTANCE
Obligate symbiotic associations with a nutritional base have likely evolved more than once in strict blood-feeding leeches. Unlike those symbioses found in hematophagous arthropods, the nature, identity, and evolutionary history of these remains poorly studied. In this work, we further explored obligate nutritional associations between leeches and their microbial symbionts, which led to the unexpected discovery of a novel symbiosis with a member of the genus. When compared to , an obligate nutritional symbiont of other leeches, this novel bacterial symbiont shows convergent retention of the metabolic pathways involved in B vitamin biosynthesis. Moreover, the genomic characteristics of this symbiont suggest a more recent association than that of and . We conclude that the once-thought stable associations between blood-feeding Glossiphoniidae and their symbionts (i.e., one bacteriome structure, one symbiont lineage) can break down, mirroring symbiont turnover observed in various arthropod lineages.
Topics: Animals; Symbiosis; Leeches; Phylogeny; Genome, Bacterial; Providencia
PubMed: 38842327
DOI: 10.1128/spectrum.04286-23 -
Nature Microbiology Jun 2024Most autotrophic organisms possess a single carbon fixation pathway. The chemoautotrophic symbionts of the hydrothermal vent tubeworm Riftia pachyptila, however, possess...
Most autotrophic organisms possess a single carbon fixation pathway. The chemoautotrophic symbionts of the hydrothermal vent tubeworm Riftia pachyptila, however, possess two functional pathways: the Calvin-Benson-Bassham (CBB) and the reductive tricarboxylic acid (rTCA) cycles. How these two pathways are coordinated is unknown. Here we measured net carbon fixation rates, transcriptional/metabolic responses and transcriptional co-expression patterns of Riftia pachyptila endosymbionts by incubating tubeworms collected from the East Pacific Rise at environmental pressures, temperature and geochemistry. Results showed that rTCA and CBB transcriptional patterns varied in response to different geochemical regimes and that each pathway is allied to specific metabolic processes; the rTCA is allied to hydrogenases and dissimilatory nitrate reduction, whereas the CBB is allied to sulfide oxidation and assimilatory nitrate reduction, suggesting distinctive yet complementary roles in metabolic function. Furthermore, our network analysis implicates the rTCA and a group 1e hydrogenase as key players in the physiological response to limitation of sulfide and oxygen. Net carbon fixation rates were also exemplary, and accordingly, we propose that co-activity of CBB and rTCA may be an adaptation for maintaining high carbon fixation rates, conferring a fitness advantage in dynamic vent environments.
Topics: Hydrothermal Vents; Carbon Cycle; Animals; Symbiosis; Polychaeta; Oxidation-Reduction; Citric Acid Cycle; Sulfides; Gene Expression Regulation, Bacterial; Hydrogenase; Chemoautotrophic Growth; Gene Expression Profiling; Nitrates; Photosynthesis; Bacteria
PubMed: 38839975
DOI: 10.1038/s41564-024-01704-y -
Journal of Morphology Jun 2024Chaetae are among the most extensively studied structures in polychaetes, serving as a defining morphological trait for annelids. Capitella teleta stands out as one of...
Chaetae are among the most extensively studied structures in polychaetes, serving as a defining morphological trait for annelids. Capitella teleta stands out as one of the few established annelid models for developmental and morphological studies, thus receiving significant scholarly attention. In this study, we unveil a previously unnoticed glandular structure associated with chaetae within the larvae of C. teleta. Our investigations demonstrate the absence of comparable structures in the chaetal follicles of adults and juveniles (older than 1 week), as well as during active chaetogenesis, underscoring the transient nature of these glands. This indicates that larval chaetal follicles transform into a gland that later disappears. Utilizing histology and transmission electron microscopy, we characterized these glands. Our findings underscore the diversity of chaetal ultrastructure in annelids and show that, even in well-studied species, novel morphological details can be found. We emphasize the importance of examining various life-history stages to capture such transient morphological features. This work lays a crucial morphological foundation and deepens our understanding of chaetae and chaetogenesis in C. teleta, paving the way for more accurate interpretations of future experimental studies on chaetogenesis in this species.
Topics: Animals; Polychaeta; Larva; Microscopy, Electron, Transmission; Annelida
PubMed: 38837266
DOI: 10.1002/jmor.21742 -
Plant Signaling & Behavior Dec 2024Earthworms' coelomic fluid (CF) has been discovered to possess properties that promote plant development. In particular, the earthworm's coelomic fluid-associated...
Earthworms' coelomic fluid (CF) has been discovered to possess properties that promote plant development. In particular, the earthworm's coelomic fluid-associated bacteria (CFB) are the primary factor influencing the plants' response. To investigate this, we used bacteria isolated from the CF and selected based on different plant growth-promoting traits, in a mesocosm ecosystem that includes plants. This experiment aimed to assess their impact on the metabolism of plants growing under abiotic stress environments (alkaline soil and nitrogen (N), phosphate (P), and potassium (K) deficit) and compare the lipid profiles of plants under the various treatments. We used seven different bacterial species isolated from the CF of and as a plant model L. For the metabolomic analysis method, we used gas chromatography-mass spectrometry lipidomic. After observing the metabolomic profiles, we found that a few molecular pathways are involved in how plants react to bacterial biostimulants. The bacterial isolates belonging to , , , and have led to a significant increase in synthesizing several metabolites belonging to various chemical categories. Contrary to predictions, abiotic stress did not cause a drop in the composition and concentration of lipids in plants treated with the CFB, demonstrating the rigidity of the protective mechanisms. The statistical analysis based on the Pearson method revealed a positive significant correlation between plant growth parameters (length of the aerial part, surface of the leaves, and biomass) and some metabolites belonging to fatty acids, carboxylic acids, benzene derivatives, and alkanes. Moreover, the standard metabolic components of all treatments in much higher concentrations during bacterial treatments than the control treatment suggests that the bacteria have stimulated the overexpression of these metabolic components. According to these results, we could assume that plants treated with CFB exhibit an adaptability of abiotic stress defense mechanisms, which may be attributed to the upregulation of genes involved in lipid biosynthesis pathways.
Topics: Stress, Physiological; Bacteria; Animals; Zea mays; Oligochaeta
PubMed: 38832593
DOI: 10.1080/15592324.2024.2363126 -
EvoDevo Jun 2024This study sheds light on the genetic blueprints of chaetogenesis (bristle formation), a complex biomineralization process essential not only for the diverse group of...
BACKGROUND
This study sheds light on the genetic blueprints of chaetogenesis (bristle formation), a complex biomineralization process essential not only for the diverse group of bristle worms (annelids) but also for other spiralians. We explore the complex genetic mechanisms behind chaetae formation in Osedax japonicus, the bone-devouring deep-sea worm known for its unique ecological niche and morphological adaptations.
RESULTS
We characterized the chaetal structure and musculature using electron microscopy and immunohistochemistry, and combined RNAseq of larval stages with in-situ hybridization chain reaction (HCR) to reveal gene expression patterns integral to chaetogenesis. Our findings pinpoint a distinct surge in gene expression during the larval stage of active chaetogenesis, identifying specific genes and cells involved.
CONCLUSIONS
Our research underscores the value of studying on non-model, "aberrant" organisms like Osedax, whose unique, temporally restricted chaetogenesis provided insights into elevated gene expression across specific larval stages and led to the identification of genes critical for chaetae formation. The genes identified as directly involved in chaetogenesis lay the groundwork for future comparative studies across Annelida and Spiralia, potentially elucidating the homology of chaetae-like chitinous structures and their evolution.
PubMed: 38831357
DOI: 10.1186/s13227-024-00227-1 -
Gene Oct 2024Earthworm, P. excavatus, is an ideal model organism for studying regeneration. Due to its prodigious regeneration capability, the amputated head part of the earthworm...
Earthworm, P. excavatus, is an ideal model organism for studying regeneration. Due to its prodigious regeneration capability, the amputated head part of the earthworm can regenerate completely within 22 days. MicroRNAs (miRNAs) regulate specific genes and are involved in essential biological processes, including regeneration. In this study, we conducted a comprehensive analysis of miRNA profiling of the earthworm, P. excavatus, during the process of anterior regeneration. Our investigation involved in the identification of 55 miRNAs from 30 distinct miRNA families that exhibit significant relevance to wound healing and regeneration. Notably, we have identified 50 novel miRNAs and predicted their pre-miRNA secondary structures using MIREAP. Both Known and Novel miRNAs are validated using qPCR. In addition, we employed the miRanda algorithm to predict the interactions between these miRNAs and their target mRNA transcripts. Based on the miRanda target prediction results, we identified the target genes such as Wnt, Myc, MAPK, SoxB, IHH, Hox, and Notch. These findings indicate that the potential targets of these miRNAs might play crucial roles in various functions related to wound healing, tissue restoration, and regeneration. Furthermore, the acquisition of these findings provides a unique perspective on understanding the molecular mechanisms driving epimorphosis regeneration in connection with miRNAs for the development of miRNA-based therapeutics.
Topics: Animals; MicroRNAs; Oligochaeta; Regeneration; Gene Expression Profiling; Wound Healing; Gene Expression Regulation
PubMed: 38830517
DOI: 10.1016/j.gene.2024.148636 -
PeerJ 2024, a genus of freshwater macrophagous leeches, belongs to Erpobdelliformes (Salifidae: Clitellata: Annelida), and , a well-known leech within this genus, has a worldwide...
BACKGROUND
, a genus of freshwater macrophagous leeches, belongs to Erpobdelliformes (Salifidae: Clitellata: Annelida), and , a well-known leech within this genus, has a worldwide distribution. However, the systematics of have not yet been adequately investigated, primarily due to a few molecular markers, and only 20 sequences available in the GenBank database. This gap significantly limits our understanding of the species identification, as well as the phylogenetic placement of the genus within Salifidae.
METHODS
Next-generation sequencing (NGS) was used to simultaneously capture the entire mitochondrial genome and the full-length 18S/28S rDNA sequences. The species boundary of species was estimated using bGMYC and bPTP methods, based on all available COI sequences. Uncorrected COI p-distance was calculated in MEGA. A molecular data matrix consisting of four loci (COI, 12S, 18S, and 28S rDNA) for outgroups (three leeches) and 49 erpobdellid leeches, representing eight genera within the Suborder Erpobdelliformes was aligned using MAFFT and LocARNA. This matrix was used to reconstruct the phylogenetic relationship of Bayesian inference (BI) and the maximum likelihood (ML) method.
RESULTS
The full lengths of the mitochondrial genome, 18S and 28S rDNAs of . cf. , are 14847 bp, 1876 bp 1876 bp, and 2863 bp, respectively. Both bGMYC and bPTP results based on COI data are generally congruent, suggesting that the previously proposed taxa (, . formosana, and . or ) are synonyms of . . The specimens listed in the group, however, are split into at least two Primary Species Hypotheses (PSHs). The p-distance of the first PSH is less than 1.3% but increased to 4.5% when including the secondary PSH (., . cf. ). In comparison, the interspecific p-distance between the group and the group ranged from 6.4% to 8.7%, and the intraspecific p-distance within the group is less than 0.8%. Considering the species delimitation results and the sufficient large p-distance, the specimen sampled in China is treated as . cf. . The monophyly of the four Erpobdelliformes families Salifidae, Orobdellidae, Gastrostomobdellidae and Erpobdellidae is well supported in ML and BI analysis based on a data of four markers. Within the Salifidae, a well-supported is closely related to a clade containing and , and these three genera are sister to a clade consisted of and . According to the results of this study, the strategy of simultaneous obtaining both whole mitochondria and nuclear markers from extensively sampled Salifids species using NGS is expected to fathom both the species diversity of and the evolutionary relationship of Salifidae.
Topics: Animals; Phylogeny; Genome, Mitochondrial; Leeches; High-Throughput Nucleotide Sequencing; RNA, Ribosomal, 28S
PubMed: 38827288
DOI: 10.7717/peerj.17480