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1.
Arch Insect Biochem Physiol ; 115(4): e22112, 2024 Apr.
Artigo em Inglês | MEDLINE | ID: mdl-38605672

RESUMO

Insect trehalases have been identified as promising new targets for pest control. These key enzymes are involved in trehalose hydrolysis and plays an important role in insect growth and development. In this contribution, plant and microbial compounds, namely validamycin A, amygdalin, and phloridzin, were evaluated for their effect, through trehalase inhibition, on Acyrthosiphon pisum aphid. The latter is part of the Aphididae family, main pests as phytovirus vectors and being very harmful for crops. Validamycin A was confirmed as an excellent trehalase inhibitor with an half maximal inhibitory concentration and inhibitor constant of 2.2 × 10-7 and 5 × 10-8 M, respectively, with a mortality rate of ~80% on a A. pisum population. Unlike validamycin A, the insect lethal efficacy of amygdalin and phloridzin did not correspond to their trehalase inhibition, probably due to their hydrolysis by insect ß-glucosidases. Our docking studies showed that none of the three compounds can bind to the trehalase active site, unlike their hydrolyzed counterparts, that is, validoxylamine A, phloretin, and prunasin. Validoxylamine A would be by far the best trehalase binder, followed by phloretin and prunasin.


Assuntos
Amigdalina , Afídeos , Inositol/análogos & derivados , Nitrilas , Animais , Afídeos/metabolismo , Trealase/metabolismo , Florizina , Insetos/metabolismo , Floretina
2.
PLoS One ; 19(3): e0299598, 2024.
Artigo em Inglês | MEDLINE | ID: mdl-38451951

RESUMO

Life tables are one of the most common tools to describe the biology of insect species and their response to environmental conditions. Although the benefits of life tables are beyond question, we raise some doubts about the completeness of the information reported in life tables. To substantiate these doubts, we consider a case study (Corcyra cephalonica) for which the raw dataset is available. The data suggest that the Gaussian approximation of the development times which is implied by the average and standard error usually reported in life tables does not describe reliably the actual distribution of the data which can be misleading and hide interesting biological aspects. Furthermore, it can be risky when life table data are used to build models to predict the demographic changes of the population. The present study highlights this aspect by comparing the impulse response generated by the raw data and by its Gaussian approximation based on the mean and the standard error. The conclusions of this paper highlight: i) the importance of adding more information to life tables and, ii) the role of raw data to ensure the completeness of this kind of studies. Given the importance of raw data, we also point out the need for further developments of a standard in the community for sharing and analysing data of life tables experiments.


Assuntos
Insetos , Lepidópteros , Animais , Tábuas de Vida , Insetos/fisiologia , Entomologia/métodos
3.
PLoS Pathog ; 20(1): e1011823, 2024 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-38236820

RESUMO

A variety of coordinated host-cell responses are activated as defense mechanisms against pore-forming toxins (PFTs). Bacillus thuringiensis (Bt) is a worldwide used biopesticide whose efficacy and precise application methods limits its use to replace synthetic pesticides in agricultural settings. Here, we analyzed the intestinal defense mechanisms of two lepidopteran insect pests after intoxication with sublethal dose of Bt PFTs to find out potential functional genes. We show that larval intestinal epithelium was initially damaged by the PFTs and that larval survival was observed after intestinal epithelium regeneration. Further analyses showed that the intestinal regeneration caused by Cry9A protein is regulated through c-Jun NH (2) terminal kinase (JNK) and Janus tyrosine kinase/signal transducer and activator of transcription (JAK/STAT) signaling pathways. JAK/STAT signaling regulates intestinal regeneration through proliferation and differentiation of intestinal stem cells to defend three different Bt proteins including Cry9A, Cry1F or Vip3A in both insect pests, Chilo suppressalis and Spodoptera frugiperda. Consequently, a nano-biopesticide was designed to improve pesticidal efficacy based on the combination of Stat double stranded RNA (dsRNA)-nanoparticles and Bt strain. This formulation controlled insect pests with better effect suggesting its potential use to reduce the use of synthetic pesticides in agricultural settings for pest control.


Assuntos
Bacillus thuringiensis , Praguicidas , Animais , Bacillus thuringiensis/genética , Janus Quinases/genética , Tirosina , Endotoxinas/genética , Insetos , Spodoptera/genética , Larva , Praguicidas/farmacologia , Regeneração , Proteínas de Bactérias/farmacologia , Proteínas de Bactérias/genética , Proteínas Hemolisinas/farmacologia , Proteínas Hemolisinas/genética , Plantas Geneticamente Modificadas , Controle Biológico de Vetores/métodos
4.
Sci Total Environ ; 912: 169304, 2024 Feb 20.
Artigo em Inglês | MEDLINE | ID: mdl-38128663

RESUMO

Metconazole (MEZ) is a novel chiral triazole fungicide that is widely used to prevent and control soil-borne fungal pathogens and other fungal diseases. However, it has a long half-life in aquatic environments and thus poses potential environmental risks. This study evaluates the acute and stereoselective cardiotoxicity of MEZ in zebrafish (Danio rerio) embryos. In addition, transcriptomics, real-time quantitative PCR, enzyme activity determination, and molecular docking are performed to evaluate the molecular mechanisms underlying the cardiotoxicity of MEZ in zebrafish. MEZ decreases the heart rate while increasing the pericardial oedema rate; additionally, it induces stereoselective cardiotoxicity. 1S,5S-MEZ exhibits stronger cardiotoxicity than 1R,5R-MEZ. Furthermore, MEZ increases the expression of Ahr-associated genes and the transcription factors il6st, il1b, and AP-1. Heart development-related genes, including fbn2b, rbm24b, and tbx20 are differentially expressed. MEZ administration alters the activities of catalase, peroxidase, and glutathione-S-transferase in zebrafish larvae. Molecular docking indicates that 1R,5R-MEZ binds more strongly to the inhibitor-binding sites of p38 in the AGE-RAGE signalling pathway than to other MEZ enantiomers. Studies conducted in vivo and in silico have established the enantioselective cardiotoxicity of MEZ and its underlying mechanisms, highlighting the need to evaluate the environmental risk of chiral MEZ in aquatic organisms at the enantiomeric level.


Assuntos
Poluentes Químicos da Água , Peixe-Zebra , Animais , Peixe-Zebra/metabolismo , Cardiotoxicidade , Simulação de Acoplamento Molecular , Triazóis/química , Embrião não Mamífero , Poluentes Químicos da Água/metabolismo
5.
Planta ; 259(1): 16, 2023 Dec 11.
Artigo em Inglês | MEDLINE | ID: mdl-38078967

RESUMO

MAIN CONCLUSION: This review provides a detailed description of the function and mechanism of VQ family gene, which is helpful for further research and application of VQ gene resources to improve crops. Valine-glutamine (VQ) motif-containing proteins are a large class of transcriptional regulatory cofactors. VQ proteins have their own unique molecular characteristics. Amino acids are highly conserved only in the VQ domain, while other positions vary greatly. Most VQ genes do not contain introns and the length of their proteins is less than 300 amino acids. A majority of VQ proteins are predicted to be localized in the nucleus. The promoter of many VQ genes contains stress or growth related elements. Segment duplication and tandem duplication are the main amplification mechanisms of the VQ gene family in angiosperms and gymnosperms, respectively. Purification selection plays a crucial role in the evolution of many VQ genes. By interacting with WRKY, MAPK, and other proteins, VQ proteins participate in the multiple signaling pathways to regulate plant growth and development, as well as defense responses to biotic and abiotic stresses. Although there have been some reports on the VQ gene family in plants, most of them only identify family members, with little functional verification, and there is also a lack of complete, detailed, and up-to-date review of research progress. Here, we comprehensively summarized the research progress of VQ genes that have been published so far, mainly including their molecular characteristics, biological functions, importance of VQ motif, and working mechanisms. Finally, the regulatory network and model of VQ genes were drawn, a precise molecular breeding strategy based on VQ genes was proposed, and the current problems and future prospects were pointed out, providing a powerful reference for further research and utilization of VQ genes in plant improvement.


Assuntos
Proteínas de Plantas , Plantas , Proteínas de Plantas/metabolismo , Motivos de Aminoácidos , Plantas/genética , Plantas/metabolismo , Regiões Promotoras Genéticas , Aminoácidos/metabolismo , Estresse Fisiológico/genética , Regulação da Expressão Gênica de Plantas , Filogenia
6.
Pest Manag Sci ; 2023 Dec 13.
Artigo em Inglês | MEDLINE | ID: mdl-38088471

RESUMO

BACKGROUND: Facultative bacterial endosymbionts have the potential to influence the interactions between aphids, their natural enemies, and host plants. Among the facultative symbionts found in populations of the grain aphid Sitobion avenae in central Chile, the bacterium Regiella insecticola is the most prevalent. In this study, we aimed to investigate whether infected and cured aphid lineages exhibit differential responses to wheat cultivars containing varying levels of the benzoxazinoid DIMBOA (2,4-dihydroxy-7-methoxy-2H-1,4-benzoxazin-3(4H)-one), which is a xenobiotic compound produced by plants. Specifically, we examined the reproductive performance responses of the most frequently encountered genotypes of Sitobion avenae when reared on wheat seedlings expressing low, medium, and high concentrations of DIMBOA. RESULTS: Our findings reveal that the intrinsic rate of population increase (rm ) in cured lineages of Sitobion avenae genotypes exhibits a biphasic pattern, characterized by the lowest rm and an extended time to first reproduction on wheat seedlings with medium levels of DIMBOA. In contrast, the aphid genotypes harbouring Regiella insecticola display idiosyncratic responses, with the two most prevalent genotypes demonstrating improved performance on seedlings featuring an intermediate content of DIMBOA compared to their cured counterparts. CONCLUSION: This study represents the first investigation into the mediating impact of facultative endosymbionts on aphid performance in plants exhibiting varying DIMBOA contents. These findings present exciting prospects for identifying novel targets for aphid control by manipulating the presence of aphid symbionts. © 2023 Society of Chemical Industry.

7.
Int J Mol Sci ; 24(19)2023 Oct 06.
Artigo em Inglês | MEDLINE | ID: mdl-37834416

RESUMO

VQ motif-containing (VQ) proteins are a class of transcription regulatory cofactors widely present in plants, playing crucial roles in growth and development, stress response, and defense. Although there have been some reports on the member identification and functional research of VQ genes in some plants, there is still a lack of large-scale identification and clear graphical presentation of their basic characterization information to help us to better understand this family. Especially in gymnosperms, the VQ family genes and their evolutionary relationships have not yet been reported. In this study, we systematically identified 2469 VQ genes from 56 plant species, including bryophytes, gymnosperms, and angiosperms, and analyzed their molecular and evolutionary features. We found that amino acids are only highly conserved in the VQ domain, while other positions are relatively variable; most VQ genes encode relatively small proteins and do not have introns. The GC content in Poaceae plants is the highest (up to 70%); these VQ proteins can be divided into nine subgroups. In particular, we analyzed the molecular characteristics, chromosome distribution, duplication events, and expression levels of VQ genes in three gymnosperms: Ginkgo biloba, Taxus chinensis, and Pinus tabuliformis. In gymnosperms, VQ genes are classified into 11 groups, with highly similar motifs in each group; most VQ proteins have less than 300 amino acids and are predicted to be located in nucleus. Tandem duplication is an important driving force for the expansion of the VQ gene family, and the evolutionary processes of most VQ genes and duplication events are relatively independent; some candidate VQ genes are preliminarily screened, and they are likely to be involved in plant growth and stress and defense responses. These results provide detailed information and powerful references for further understanding and utilizing the VQ family genes in various plants.


Assuntos
Cycadopsida , Proteínas de Plantas , Proteínas de Plantas/metabolismo , Cycadopsida/genética , Cycadopsida/metabolismo , Regulação da Expressão Gênica de Plantas , Plantas/metabolismo , Aminoácidos/metabolismo , Filogenia
8.
Plant Biotechnol J ; 21(11): 2389-2407, 2023 11.
Artigo em Inglês | MEDLINE | ID: mdl-37540474

RESUMO

Aphid salivary proteins are critical in modulating plant defence responses. Grain aphid Sitobion miscanthi is an important wheat pest worldwide. However, the molecular basis for the regulation of the plant resistance to cereal aphids remains largely unknown. Here, we show that SmCSP4, a chemosensory protein from S. miscanthi saliva, is secreted into wheat plants during aphid feeding. Delivery of SmCSP4 into wheat leaves activates salicylic acid (SA)-mediated plant defence responses and subsequently reduces aphid performance by deterring aphid feeding behaviour. In contrast, silencing SmCSP4 gene via nanocarrier-mediated RNAi significantly decreases the ability of aphids to activate SA defence pathway. Protein-protein interaction assays showed that SmCSP4 directly interacts with wheat transcriptional factor TaWRKY76 in plant nucleus. Furthermore, TaWRKY76 directly binds to the promoter of SA degradation gene Downy Mildew Resistant 6 (DMR6) and regulates its gene expression as transcriptional activator. SmCSP4 secreted by aphids reduces the transcriptional activation activity of TaWRKY76 on DMR6 gene expression, which is proposed to result in increases of SA accumulation and enhanced plant immunity. This study demonstrated that SmCSP4 acts as salivary elicitor that is involved in activating SA signalling defence pathway of wheat by interacting with TaWRKY76, which provide novel insights into aphid-cereal crops interactions and the molecular mechanism on induced plant immunity.


Assuntos
Afídeos , Saliva , Animais , Saliva/metabolismo , Afídeos/fisiologia , Triticum/metabolismo , Fatores de Transcrição/genética , Fatores de Transcrição/metabolismo , Ácido Salicílico/metabolismo
9.
Sci Data ; 10(1): 274, 2023 05 12.
Artigo em Inglês | MEDLINE | ID: mdl-37173339

RESUMO

The spotted alfalfa aphid (SAA, Therioaphis trifolii) (Hemiptera: Aphididae) is a destructive pest of cultivated alfalfa (Medicago sativa L.) that leads to large financial losses in the livestock industry around the world. Here, we present a chromosome-scale genome assembly of T. trifolii, the first genome assembly for the aphid subfamily Calaphidinae. Using PacBio long-read sequencing, Illumina sequencing, and Hi-C scaffolding techniques, a 541.26 Mb genome was generated, with 90.01% of the assembly anchored into eight scaffolds, and the contig and scaffold N50 are 2.54 Mb and 44.77 Mb, respectively. BUSCO assessment showed a completeness score of 96.6%. A total of 13,684 protein-coding genes were predicted. The high-quality genome assembly of T. trifolii not only provides a genomic resource for the more complete analysis of aphid evolution, but also provides insights into the ecological adaptation and insecticide resistance of T. trifolii.


Assuntos
Afídeos , Cromossomos de Insetos , Genoma de Inseto , Animais , Afídeos/genética , Genômica/métodos , Medicago sativa/genética , Filogenia
10.
Int. microbiol ; 26(2): 397-409, May. 2023. ilus
Artigo em Inglês | IBECS | ID: ibc-220231

RESUMO

The current plastic pollution throughout the world is a rising concern that demands the optimization of biodegradation processes. One avenue for this is to identify plastic-degrading bacteria and associated enzymes from the gut bacteria of insect models such as Tenebrio molitor, Plodia interpunctella or Galleria mellonella that have the ability to ingest and rapidly degrade polyethylene. Therefore, this study takes part in understanding the role of the gut bacteria by investigating G. mellonella as a biological model feeding with a diet based on honeybee wax mixed or not with low-density polyethylene. Gut microbiome was analyzed by high throughput 16S rRNA sequencing, and Enterococcaceae and Oxalobacteraceae were found to be the major bacterial families. Compared to the control, the supplementation of low-density polyethylene did not cause significant modification of the bacterial microbiota at community and taxa levels, suggesting bacterial microbiome resilience. The bacterial proteome analysis of gut contents was encouraging for the identification of plastic degrading enzymes such as the phenylacetaldehyde dehydrogenase which participate in styrene degradation. This study allowed a better characterization of the gut bacteria of G. mellonella and provided a basis for the further study of biodegradation of polyethylene based on the bacterial microbiota from insect guts.(AU)


Assuntos
Humanos , Biodegradação Ambiental , Plásticos , Polietileno , Lepidópteros , Microbiologia , Técnicas Microbiológicas
11.
Chemosphere ; 325: 138431, 2023 Jun.
Artigo em Inglês | MEDLINE | ID: mdl-36933840

RESUMO

Cyflumetofen (CYF), a novel chiral acaricide, exert enantiomer-specific effects on target organisms by binding to glutathione S-transferase. However, there is limited knowledge regarding the response of non-target organisms to CYF, including enantioselective toxicity. In this study, we investigated the effects of racemic CYF (rac-CYF) and its two enantiomers (+)-CYF and (-)-CYF on MCF-7 cells and non-target (honeybees) and target (bee mites and red spider mites) organisms. The results showed that similar to estradiol, 1 µM (+)-CYF promoted the proliferation and disturbed the redox homeostasis of MCF-7 cells, whereas at high concentrations (≥100 µM) it exerted a negative effect on cell viability that was substantially stronger than that of (-)-CYF or rac-CYF. (-)-CYF and rac-CYF at 1 µM concentration did not significantly affect cell proliferation, but caused cell damage at high concentrations (≥100 µM). Analysis of acute CYF toxicity against non-target and target organisms revealed that for honeybees, all CYF samples had high lethal dose (LD50) values, indicating low toxicity. In contrast, for bee mites and red spider mites, LD50 values were low, whereas those of (+)-CYF were the lowest, suggesting higher toxicity of (+)-CYF than that of the other CYF samples. Proteomics profiling revealed potential CYF-targeted proteins in honeybees related to energy metabolism, stress responses, and protein synthesis. Upregulation of estrogen-induced FAM102A protein analog indicated that CYF might exert estrogenic effects by dysregulating estradiol production and altering estrogen-dependent protein expression in bees. Our findings suggest that CYF functions as an endocrine disruptor in non-target organisms in an enantiomer-specific manner, indicating the necessity for general ecological risk assessment for chiral pesticides.


Assuntos
Acaricidas , Praguicidas , Abelhas , Animais , Acaricidas/toxicidade , Estereoisomerismo , Praguicidas/química , Propionatos/análise , Proteínas
12.
J Agric Food Chem ; 71(14): 5554-5564, 2023 Apr 12.
Artigo em Inglês | MEDLINE | ID: mdl-36995163

RESUMO

Fusarium head blight (FHB), caused by Fusarium graminearum, whose occurrence and prevalence causes 10-70% wheat production loss, is one of the most destructive diseases influencing the production of wheat globally. To identify the potential natural products (NPs) against F. graminearum, we screened 59 Xenorhabdus strains and discovered that the cell-free supernatant (CFS) of X. budapestensis 14 (XBD14) displays the highest bioactivity. Multiple genetic methods coupled with HRMS/MS analysis determined the major antifungal NP to be Fcl-29, a fabclavine derivative. Fcl-29 was found to effectively control FHB of wheat in the field test and demonstrated broad-spectrum antifungal activity against important pathogenic fungi. The production of Fcl-29 was dramatically improved by 33.82-fold with the combinatorial strategy of genetic engineering (1.66-fold) and fermentation engineering (20.39-fold). The exploration of a new biofungicide in global plant protection is now possible.


Assuntos
Antifúngicos , Fusarium , Doenças das Plantas/microbiologia , Triticum/genética
13.
Front Plant Sci ; 14: 1096750, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-36818877

RESUMO

Bacterial symbionts associated with aphids are important for their ecological fitness. The corn leaf aphid, Rhopalosiphum maidis (Fitch), is one of the most damaging aphid pests on maize and has been reported to harbor Hamiltonella defensa and Regiella insecticola while the effects of the secondary symbionts (S-symbionts) on host ecology and primary symbiont Buchnera aphidicola remain unclear. Here, four aphid strains were established, two of which were collected from Langfang - Hebei Province, China, with similar symbiont pattern except for the presence of H. defensa. Two other aphid strains were collected from Nanning - Guangxi Province, China, with the same symbiont infection except for the presence of R. insecticola. Phylogenetic analysis and aphid genotyping indicated that the S-symbiont-infected and free aphid strains from the same location had identical genetic backgrounds. Aphid fitness measurement showed that aphid strain infected with H. defensa performed shortened developmental duration for 1st instar and total nymph stages, reduced aphid survival rate, offspring, and longevity. While the developmental duration of H-infected strains was accelerated, and the adult weight was significantly higher compared to the H-free strain. Infection with R. insecticola did not affect the aphid's entire nymph stage duration and survival rate. As the H-strain does, aphids infected with R. insecticola also underwent a drop in offspring, along with marginally lower longevity. Unlike the H-infected strain, the R-infected strain performed delayed developmental duration and lower adult weight. The B. aphidicola titers of the H-infected strains showed a steep drop during the aphid 1st to 3rd instar stages, while the augmentation of B. aphidicola titers was found in the R-infected strain during the aphid 1st to 3rd instar. Our study investigated for the first time the effect of the S-symbionts on the ecology fitness and primary symbiont in R. maidis, indicating that infection with secondary symbionts leads to the modulation of aphid primary symbiont abundance, together inducing significant fitness costs on aphids with further impact on environmental adaptation and trophic interactions.

14.
Insects ; 14(2)2023 Feb 02.
Artigo em Inglês | MEDLINE | ID: mdl-36835722

RESUMO

Broad bean weevils (BBWs-Coleoptera: Chrysomelidae) are serious pests of field bean seeds that hamper the promotion of this crop in the diversification of European cropping systems. Recent research has identified different semiochemical lures and trap devices for the development of semiochemical-based control strategies of BBWs. In this study, two field trials were carried out in order to provide necessary information supporting the implementation of sustainable field use of semiochemical traps against BBWs. More particularly, three principal objectives were followed including (i) the identification of the most efficient traps for BBWs capture and the influence of trapping modality on BBWs sex-ratio, (ii) the assessment of eventual collateral effects on crop benefits including aphidophagous and pollinator insects such as Apidae, Syrphidae and Coccinellidae, (iii) the assessment of the crop developmental stage influence on the capture by semiochemical traps. Three different semiochemical lures were tested in combination with two trapping devices across two field trials in early and late flowering field bean crops. The crop phenology and climate parameters were integrated into the analyses to interpret the spatiotemporal evolution of the captured insect populations. A total of 1380 BBWs and 1424 beneficials were captured. White pan traps combined with floral kairomones were the most efficient traps for the capture of BBWs. We demonstrated that the crop phenology (c.f., the flowering stage) exerted strong competition on the attractiveness of semiochemical traps. Community analysis revealed that only one species of BBWs was captured in field bean crops (i.e., Bruchus rufimanus), and no trend was highlighted concerning the sex ratios according to the trapping devices. The beneficial insect community included 67 different species belonging to bees, hoverflies and ladybeetles. Semiochemical traps manifested a strong impact on beneficial insect communities that included some species under extinction threats and need to be further adapted to minimize such collateral effects. Based on these results, recommendations are provided for the implementation of the most sustainable BBWs control method that minimizes the impact on the recruitment of beneficial insects, which is an important ecosystem service for faba bean crops.

15.
Insects ; 14(1)2023 Jan 06.
Artigo em Inglês | MEDLINE | ID: mdl-36661985

RESUMO

Population genetic studies can reveal clues about the evolution of adaptive strategies of aphid species in agroecosystems and demonstrate the influence of environmental factors on the genetic diversity and gene flow among aphid populations. To investigate the genetic diversity of two Rhopalosiphum aphid species from different geographical regions, 32 populations (n = 535) of the bird cherry-oat aphid (Rhopalosiphum padi Linnaeus) and 38 populations (n = 808) of the corn leaf aphid (Rhopalosiphum maidis Fitch) from China and Europe were analyzed using one nuclear (elongation factor-1 alpha) and two mitochondrial (cytochrome oxidase I and II) genes. Based on the COI-COII sequencing, two obvious clades between Chinese and European populations and a low level of gene flow (Nm = 0.15) were detected in R. padi, while no geographical-associated genetic variation was found for EF-1α in this species. All genes in R. maidis had low genetic variation, indicating a high level of gene flow (Nm = 5.31 of COI-COII and Nm = 2.89 of EF-1α). Based on the mitochondrial result of R. padi, we concluded that the long distance between China and Europe may be interrupting the gene flow. The discordant results of nuclear gene analyses in R. padi may be due to the slower evolution of nuclear genes compared to mitochondrial genes. The gene exchange may occur gradually with the potential for continuous migration of the aphid. This study facilitates the design of control strategies for these pests.

16.
Int Microbiol ; 26(2): 397-409, 2023 May.
Artigo em Inglês | MEDLINE | ID: mdl-36484909

RESUMO

The current plastic pollution throughout the world is a rising concern that demands the optimization of biodegradation processes. One avenue for this is to identify plastic-degrading bacteria and associated enzymes from the gut bacteria of insect models such as Tenebrio molitor, Plodia interpunctella or Galleria mellonella that have the ability to ingest and rapidly degrade polyethylene. Therefore, this study takes part in understanding the role of the gut bacteria by investigating G. mellonella as a biological model feeding with a diet based on honeybee wax mixed or not with low-density polyethylene. Gut microbiome was analyzed by high throughput 16S rRNA sequencing, and Enterococcaceae and Oxalobacteraceae were found to be the major bacterial families. Compared to the control, the supplementation of low-density polyethylene did not cause significant modification of the bacterial microbiota at community and taxa levels, suggesting bacterial microbiome resilience. The bacterial proteome analysis of gut contents was encouraging for the identification of plastic degrading enzymes such as the phenylacetaldehyde dehydrogenase which participate in styrene degradation. This study allowed a better characterization of the gut bacteria of G. mellonella and provided a basis for the further study of biodegradation of polyethylene based on the bacterial microbiota from insect guts.


Assuntos
Mariposas , Polietileno , Humanos , Abelhas/genética , Animais , Larva/metabolismo , Larva/microbiologia , Polietileno/metabolismo , RNA Ribossômico 16S/genética , Mariposas/genética , Mariposas/metabolismo , Mariposas/microbiologia , Plásticos/metabolismo , Bactérias/genética , Bactérias/metabolismo , Dieta , Suplementos Nutricionais
17.
Int J Biol Macromol ; 226: 510-524, 2023 Jan 31.
Artigo em Inglês | MEDLINE | ID: mdl-36509203

RESUMO

(E)-ß-farnesene (EBF) is a typical and ecologically important infochemical in tri-trophic level interactions among plant-aphid-natural enemies. However, the molecular mechanisms by which parasitoids recognize and utilize EBF are unclear. In this study, we functionally characterized 8 AgifOBPs in Aphidifus gifuensis, one dominant endo-parasitoid of wheat aphid as well as peach aphid in China. Among which, AgifOBP6 was the only OBP upregulated by various doses of EBF, and it showed a strong binding affinity to EBF in vitro. The lack of homology between AgifOBP6 and EBF-binding proteins from aphids or from other aphid natural enemies supported that this was a convergent evolution among insects from different orders driven by EBF. Molecular docking of AgifOBP6 with EBF revealed key interacting residues and hydrophobic forces as the main forces. AgifOBP6 is widely expressed among various antennal sensilla. Furthermore, two bioassays indicated that trace EBF may promote the biological control efficiency of A. gifuensis, especially on winged aphids. In summary, this study reveals an OBP (AgifOBP6) that may play a leading role in aphid alarm pheromone detection by parasitoids and offers a new perspective on aphid biological control by using EBF. These results will improve our understanding of tri-trophic level interactions among plant-aphid-natural enemies.


Assuntos
Afídeos , Animais , Simulação de Acoplamento Molecular , Odorantes , Feromônios/metabolismo , China
18.
Biodivers Data J ; 11: e102897, 2023.
Artigo em Inglês | MEDLINE | ID: mdl-38327342

RESUMO

In the context of global insect decline, the urbanisation process plays a key role. However, urban pavements, which are considered to be impervious to biodiversity, can harbour ground-nesting insects under certain conditions. Recent observations have revealed the presence of Formicidae nests under urban pavements. The aim of this work is to determine the species richness of Formicidae nesting under urban pavements in the Brussels-Capital Region (Belgium) and to characterise their nest environment and soil texture. Seven ant species were identified in 120 nesting sites: Lasiusniger, Lasiusbrunneus, Lasiusflavus, Lasiusfuliginosus, Tetramoriumcaespitum, Tetramoriumimpurum and Myrmicarugulosa. Concrete slabs or natural stones with a sandy sub-layer are the main structures in which ants nest. In addition, nests were mainly found under modular pavements with degraded rigid joints. The results of this work highlight the capacity of urban structures to host part of ant biodiversity in cities.

19.
Plants (Basel) ; 11(23)2022 Dec 02.
Artigo em Inglês | MEDLINE | ID: mdl-36501390

RESUMO

Sitobion miscanthi, an important viral vector of barley yellow dwarf virus (BYDV), is also symbiotically associated with endosymbionts, but little is known about the interactions between endosymbionts, aphid and BYDV. Therefore, two aphids' geographic populations, differing in their BYDV transmission efficiency, after characterizing their endosymbionts, were treated with antibiotics to investigate how changes in the composition of their endosymbiont population affected BYDV transmission efficiency. After antibiotic treatment, Rickettsia was eliminated from two geographic populations. BYDV transmission efficiency by STY geographic population dropped significantly, by -44.2% with ampicillin and -25.01% with rifampicin, but HDZ geographic population decreased by only 14.19% with ampicillin and 23.88% with rifampicin. Transcriptomic analysis showed that the number of DEGs related to the immune system, carbohydrate metabolism and lipid metabolism did increase in the STY rifampicin treatment, while replication and repair, glycan biosynthesis and metabolism increased in the STY ampicillin treatment. Proteomic analysis showed that the abundance of symbionin symL, nascent polypeptide-associated complex subunit alpha and proteasome differed significantly between the two geographic populations. We found that the endosymbionts can mediate vector viral transmission. They should therefore be included in investigations into aphid-virus interactions and plant disease epidemiology. Our findings should also help with the development of strategies to prevent virus transmission.

20.
Insects ; 13(11)2022 Oct 29.
Artigo em Inglês | MEDLINE | ID: mdl-36354818

RESUMO

This study analyzed the protein content of ten edible insect species (using the Dumas method), then focused on the amino acid (AA) profiles of the six major commercially relevant species using HPLC (high-pressure (or performance) liquid chromatography). The protein contents varied significantly from 46.1% to 52.9% (dry matter); the Orthoptera representative yielding both the highest protein content and the highest values in three essential amino acids (EAAs). Regarding Lepidoptera species, the protein content of Saturniidae varied more than for Notodontidae. Imbrasia ertli gave the best example of a species that could be suggested for dietary supplementation of cereal-based diets, as the sample contained the highest values in five EAAs and for the EAA index. Furthermore, first-limiting AAs in the selected insects have also been pointed out (based on a species-specific AA score), supporting that the real benefit from eating insects is correlated to a varied diet. Additionally, preliminary insights into AA distribution patterns according to taxa provided three clusters based on protein quality and should be completed further to help tailor prescriptions of dietary diets. Since the AA composition of the selected insects was close to the FAO/WHO EAA requirement pattern for preschool children and met the requirements of 40% EAAs with high ratio EAAs/NEAAs, the current study endorses reports of edible insects as nutrient-rich and sustainable protein sources.

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