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1.
Nat Commun ; 15(1): 3965, 2024 May 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730017

RESUMEN

Currently, there is no pesticide available for the selective control of the pine processionary moth (Thaumetopoea pityocampa-specific), and conventional methods typically rely on mechanical techniques such as pheromone traps or broad-spectrum larvicidal chemicals. As climate change increases the range and dispersion capacity of crop and forest pests, outbreaks of the pine processionary occur with greater frequency and significantly impact forestry and public health. Our study is carried out to provide a T. pityocampa-specific pesticide targeting the Allatostatin Type-C Receptor (AlstR-C). We use a combination of computational biology methods, a cell-based screening assay, and in vivo toxicity and side effect assays to identify, for the first time, a series of AlstR-C ligands suitable for use as T. pityocampa-specific insecticides. We further demonstrate that the novel AlstR-C targeted agonists are specific to lepidopteran larvae, with no harmful effects on coleopteran larvae or adults. Overall, our study represents an important initial advance toward an insect GPCR-targeted next-generation pesticide design. Our approach may apply to other invertebrate GPCRs involved in vital metabolic pathways.


Asunto(s)
Insecticidas , Larva , Mariposas Nocturnas , Animales , Mariposas Nocturnas/efectos de los fármacos , Insecticidas/farmacología , Larva/efectos de los fármacos , Proteínas de Insectos/metabolismo , Receptores Acoplados a Proteínas G/agonistas , Receptores Acoplados a Proteínas G/metabolismo , Humanos , Ligandos , Neuropéptidos
2.
Sci Rep ; 14(1): 10758, 2024 05 10.
Artículo en Inglés | MEDLINE | ID: mdl-38730020

RESUMEN

Staphylococcus aureus is a frequent agent of bacteraemia. This bacterium has a variety of virulence traits that allow the establishment and maintenance of infection. This study explored the virulence profile of S. aureus strains causing paediatric bacteraemia (SAB) in Manhiça district, Mozambique. We analysed 336 S. aureus strains isolated from blood cultures of children younger than 5 years admitted to the Manhiça District Hospital between 2001 and 2019, previously characterized for antibiotic susceptibility and clonality. The strains virulence potential was evaluated by PCR detection of the Panton-Valentine leucocidin (PVL) encoding genes, lukS-PV/lukF-PV, assessment of the capacity for biofilm formation and pathogenicity assays in Galleria mellonella. The overall carriage of PVL-encoding genes was over 40%, although reaching ~ 70 to 100% in the last years (2014 to 2019), potentially linked to the emergence of CC152 lineage. Strong biofilm production was a frequent trait of CC152 strains. Representative CC152 and CC121 strains showed higher virulence potential in the G. mellonella model when compared to reference strains, with variations within and between CCs. Our results highlight the importance of monitoring the emergent CC152-MSSA-PVL+ and other lineages, as they display important virulence traits that may negatively impact the management of SAB paediatric patients in Manhiça district, Mozambique.


Asunto(s)
Bacteriemia , Biopelículas , Infecciones Comunitarias Adquiridas , Infecciones Estafilocócicas , Staphylococcus aureus , Humanos , Mozambique/epidemiología , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidad , Staphylococcus aureus/aislamiento & purificación , Virulencia/genética , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/epidemiología , Biopelículas/crecimiento & desarrollo , Preescolar , Bacteriemia/microbiología , Bacteriemia/epidemiología , Infecciones Comunitarias Adquiridas/microbiología , Lactante , Animales , Exotoxinas/genética , Toxinas Bacterianas/genética , Leucocidinas/genética , Factores de Virulencia/genética , Femenino , Masculino , Mariposas Nocturnas/microbiología
3.
Int J Mol Sci ; 25(9)2024 Apr 24.
Artículo en Inglés | MEDLINE | ID: mdl-38731841

RESUMEN

Plutella xylostella (Linnaeus) mainly damages cruciferous crops and causes huge economic losses. Presently, chemical pesticides dominate its control, but prolonged use has led to the development of high resistance. In contrast, the sterile insect technique provides a preventive and control method to avoid the development of resistance. We discovered two genes related to the reproduction of Plutella xylostella and investigated the efficacy of combining irradiation with RNA interference for pest management. The results demonstrate that after injecting PxAKT and PxCDK5, there was a significant decrease of 28.06% and 25.64% in egg production, and a decrease of 19.09% and 15.35% in the hatching rate compared to the control. The ratio of eupyrene sperm bundles to apyrene sperm bundles also decreased. PxAKT and PxCDK5 were identified as pivotal genes influencing male reproductive processes. We established a dose-response relationship for irradiation (0-200 Gy and 200-400 Gy) and derived the irradiation dose equivalent to RNA interference targeting PxAKT and PxCDK5. Combining RNA interference with low-dose irradiation achieved a sub-sterile effect on Plutella xylostella, surpassing either irradiation or RNA interference alone. This study enhances our understanding of the genes associated with the reproduction of Plutella xylostella and proposes a novel approach for pest management by combining irradiation and RNA interference.


Asunto(s)
Quinasa 5 Dependiente de la Ciclina , Proteínas Proto-Oncogénicas c-akt , Interferencia de ARN , Animales , Masculino , Proteínas Proto-Oncogénicas c-akt/metabolismo , Proteínas Proto-Oncogénicas c-akt/genética , Quinasa 5 Dependiente de la Ciclina/genética , Quinasa 5 Dependiente de la Ciclina/metabolismo , Fertilidad/efectos de la radiación , Fertilidad/genética , Mariposas Nocturnas/genética , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Femenino , Reproducción/efectos de la radiación , Reproducción/genética
4.
BMC Biol ; 22(1): 102, 2024 May 01.
Artículo en Inglés | MEDLINE | ID: mdl-38693535

RESUMEN

BACKGROUND: Sex-limited chromosomes Y and W share some characteristics, including the degeneration of protein-coding genes, enrichment of repetitive elements, and heterochromatin. However, although many studies have suggested that Y chromosomes retain genes related to male function, far less is known about W chromosomes and whether they retain genes related to female-specific function. RESULTS: Here, we built a chromosome-level genome assembly of the Asian corn borer, Ostrinia furnacalis Guenée (Lepidoptera: Crambidae, Pyraloidea), an economically important pest in corn, from a female, including both the Z and W chromosome. Despite deep conservation of the Z chromosome across Lepidoptera, our chromosome-level W assembly reveals little conservation with available W chromosome sequence in related species or with the Z chromosome, consistent with a non-canonical origin of the W chromosome. The W chromosome has accumulated significant repetitive elements and experienced rapid gene gain from the remainder of the genome, with most genes exhibiting pseudogenization after duplication to the W. The genes that retain significant expression are largely enriched for functions in DNA recombination, the nucleosome, chromatin, and DNA binding, likely related to meiotic and mitotic processes within the female gonad. CONCLUSIONS: Overall, our chromosome-level genome assembly supports the non-canonical origin of the W chromosome in O. furnacalis, which experienced rapid gene gain and loss, with the retention of genes related to female-specific function.


Asunto(s)
Cromosomas de Insectos , Mariposas Nocturnas , Cromosomas Sexuales , Animales , Mariposas Nocturnas/genética , Femenino , Cromosomas Sexuales/genética , Cromosomas de Insectos/genética , Masculino , Evolución Molecular , Genoma de los Insectos
5.
Biol Lett ; 20(5): 20230610, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38747686

RESUMEN

Echolocating bats and their eared insect prey are in an acoustic evolutionary war. Moths produce anti-bat sounds that startle bat predators, signal noxiousness, mimic unpalatable models and jam bat sonar. Tiger beetles (Cicindelidae) also purportedly produce ultrasound in response to bat attacks. Here we tested 19 tiger beetle species from seven genera and showed that they produce anti-bat signals to playback of authentic bat echolocation. The dominant frequency of beetle sounds substantially overlaps the sonar calls of sympatric bats. As tiger beetles are known to produce defensive chemicals such as benzaldehyde and hydrogen cyanide, we hypothesized that tiger beetle sounds are acoustically advertising their unpalatability. We presented captive big brown bats (Eptesicus fuscus) with seven different tiger beetle species and found that 90 out of 94 beetles were completely consumed, indicating that these tiger beetle species are not aposematically signalling. Instead, we show that the primary temporal and spectral characteristics of beetle warning sounds overlap with sympatric unpalatable tiger moth (Arctinae) sounds and that tiger beetles are probably Batesian mimics of noxious moth models. We predict that many insect taxa produce anti-bat sounds and that the acoustic mimicry rings of the night sky are hyperdiverse.


Asunto(s)
Quirópteros , Escarabajos , Ecolocación , Mariposas Nocturnas , Animales , Mariposas Nocturnas/fisiología , Quirópteros/fisiología , Escarabajos/fisiología , Conducta Predatoria , Mimetismo Biológico
6.
J Med Microbiol ; 73(5)2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38743467

RESUMEN

Introduction . Acinetobacter baumannii is a critical priority pathogen for novel antimicrobials (World Health Organization) because of the rise in nosocomial infections and its ability to evolve resistance to last resort antibiotics. A. baumannii is thus a priority target for phage therapeutics. Two strains of a novel, virulent bacteriophage (LemonAid and Tonic) able to infect carbapenem-resistant A. baumannii (strain NCTC 13420), were isolated from environmental water samples collected through a citizen science programme.Gap statement. Phage-host coevolution can lead to emergence of host resistance, with a concomitant reduction in the virulence of host bacteria; a potential benefit to phage therapy applications.Methodology. In vitro and in vivo assays, genomics and microscopy techniques were used to characterize the phages; determine mechanisms and impact of phage resistance on host virulence, and the efficacy of the phages against A. baumannii.Results. A. baumannii developed resistance to both viruses, LemonAid and Tonic. Resistance came at a cost to virulence, with the resistant variants causing significantly reduced mortality in a Galleria mellonella larval in vivo model. A replicated 8 bp insertion increased in frequency (~40 % higher frequency than in the wild-type) within phage-resistant A. baumannii mutants, putatively resulting in early truncation of a protein of unknown function. Evidence from comparative genomics and an adsorption assay suggests this protein acts as a novel phage receptor site in A. baumannii. We find no evidence linking resistance to changes in capsule structure, a known virulence factor. LemonAid efficiently suppressed growth of A. baumanni in vitro across a wide range of titres. However, in vivo, while survival of A. baumannii infected larvae significantly increased with both remedial and prophylactic treatment with LemonAid (107 p.f.u. ml-1), the effect was weak and not sufficient to save larvae from morbidity and mortality.Conclusion. While LemonAid and Tonic did not prove effective as a treatment in a Galleria larvae model, there is potential to harness their ability to attenuate virulence in drug-resistant A. baumannii.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Bacteriófagos , Acinetobacter baumannii/virología , Acinetobacter baumannii/efectos de los fármacos , Acinetobacter baumannii/patogenicidad , Acinetobacter baumannii/genética , Bacteriófagos/genética , Bacteriófagos/fisiología , Virulencia , Infecciones por Acinetobacter/microbiología , Animales , Mariposas Nocturnas/microbiología , Mariposas Nocturnas/virología , Terapia de Fagos , Antibacterianos/farmacología , Farmacorresistencia Bacteriana , Larva/microbiología , Larva/virología
7.
J Agric Food Chem ; 72(19): 10958-10969, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38703118

RESUMEN

Demand for the exploration of botanical pesticides continues to increase due to the detrimental effects of synthetic chemicals on human health and the environment and the development of resistance by pests. Under the guidance of a bioactivity-guided approach and HSQC-based DeepSAT, 16 coumarin derivatives were discovered from the leaves of Ailanthus altissima (Mill.) Swingle, including seven undescribed monoterpenoid coumarins, three undescribed monoterpenoid phenylpropanoids, and two new coumarin derivatives. The structure and configurations of these compounds were established and validated via extensive spectroscopic analysis, acetonide analysis, and quantum chemical calculations. Biologically, 5 exhibited significant antifeedant activity toward the Plutella xylostella. Moreover, tyrosinase being closely related to the growth and development of larva, the inhibitory potentials of 5 against tyrosinase was evaluated in vitro and in silico. The bioactivity evaluation results highlight the prospect of 5 as a novel category of botanical insecticide.


Asunto(s)
Ailanthus , Cumarinas , Insecticidas , Extractos Vegetales , Hojas de la Planta , Hojas de la Planta/química , Animales , Cumarinas/farmacología , Cumarinas/química , Ailanthus/química , Extractos Vegetales/química , Extractos Vegetales/farmacología , Insecticidas/química , Insecticidas/farmacología , Estructura Molecular , Larva/efectos de los fármacos , Larva/crecimiento & desarrollo , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/crecimiento & desarrollo , Monofenol Monooxigenasa/antagonistas & inhibidores , Monofenol Monooxigenasa/metabolismo , Bioensayo , Monoterpenos/farmacología , Monoterpenos/química , Conducta Alimentaria/efectos de los fármacos , Inhibidores Enzimáticos/farmacología , Inhibidores Enzimáticos/química
8.
J Agric Food Chem ; 72(19): 10794-10804, 2024 May 15.
Artículo en Inglés | MEDLINE | ID: mdl-38711396

RESUMEN

Chitin-degrading enzymes are critical components in regulating the molting process of the Asian corn borer and serve as potential targets for controlling this destructive pest of maize. Here, we used a scaffold-hopping strategy to design a series of efficient naphthylimide insecticides. Among them, compound 8c exhibited potent inhibition of chitinase from OfChi-h and OfChtI at low nanomolar concentrations (IC50 = 1.51 and 9.21 nM, respectively). Molecular docking simulations suggested that 8c binds to chitinase by mimicking the interaction of chitin oligosaccharide substrates with chitinase. At low ppm concentrations, compound 8c performed comparably to commercial insecticides in controlling the highly destructive plant pest, the Asian corn borer. Tests on a wide range of nontarget organisms indicate that compound 8c has very low toxicity. In addition, the effect of inhibitor treatment on the expression of genes associated with the Asian corn borer chitin-degrading enzymes was further investigated by quantitative real-time polymerase chain reaction. In conclusion, our study highlights the potential of 8c as a novel chitinase-targeting insecticide for effective control of the Asian corn borer, providing a promising solution in the quest for sustainable pest management.


Asunto(s)
Quitina , Quitinasas , Proteínas de Insectos , Insecticidas , Simulación del Acoplamiento Molecular , Mariposas Nocturnas , Zea mays , Animales , Quitinasas/química , Quitinasas/genética , Quitinasas/metabolismo , Mariposas Nocturnas/enzimología , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/genética , Quitina/química , Quitina/metabolismo , Insecticidas/química , Insecticidas/farmacología , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Proteínas de Insectos/química , Proteínas de Insectos/antagonistas & inhibidores , Zea mays/química , Zea mays/parasitología , Inhibidores Enzimáticos/química , Inhibidores Enzimáticos/farmacología , Diseño de Fármacos , Control de Insectos , Larva/crecimiento & desarrollo , Larva/efectos de los fármacos , Relación Estructura-Actividad
9.
Environ Microbiol Rep ; 16(3): e13213, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38738810

RESUMEN

Since a significant proportion of plant matter is consumed by herbivores, a necessary adaptation for many phyllosphere microbes could be to survive through the guts of herbivores. While many studies explore the gut microbiome of herbivores by surveying the microbiome in their frass, few studies compare the phyllosphere microbiome to the gut microbiome of herbivores. High-throughput metabarcode sequencing was used to track the fungal community from milkweed (Asclepias spp.) leaves to monarch caterpillar frass. The most commonly identified fungal taxa that dominated the caterpillar frass after the consumption of leaves were yeasts, mostly belonging to the Basidiomycota phylum. While most fungal communities underwent significant bottlenecks and some yeast taxa increased in relative abundance, a consistent directional change in community structure was not identified from leaf to caterpillar frass. These results suggest that some phyllosphere fungi, especially diverse yeasts, can survive herbivory, but whether herbivory is a key stage of their life cycle remains uncertain. For exploring phyllosphere fungi and the potential coprophilous lifestyles of endophytic and epiphytic fungi, methods that target yeast and Basidiomycota fungi are recommended.


Asunto(s)
Asclepias , Hongos , Herbivoria , Hojas de la Planta , Animales , Hojas de la Planta/microbiología , Asclepias/microbiología , Hongos/clasificación , Hongos/genética , Hongos/aislamiento & purificación , Hongos/fisiología , Levaduras/clasificación , Levaduras/aislamiento & purificación , Levaduras/genética , Micobioma , Basidiomycota/clasificación , Basidiomycota/genética , Basidiomycota/fisiología , Basidiomycota/aislamiento & purificación , Microbioma Gastrointestinal , Larva/microbiología , Mariposas Nocturnas/microbiología
10.
Nat Commun ; 15(1): 4036, 2024 May 13.
Artículo en Inglés | MEDLINE | ID: mdl-38740750

RESUMEN

Microbial Ni2+ homeostasis underpins the virulence of several clinical pathogens. Ni2+ is an essential cofactor in urease and [NiFe]-hydrogenases involved in colonization and persistence. Many microbes produce metallophores to sequester metals necessary for their metabolism and starve competing neighboring organisms. The fungal metallophore aspergillomarasmine A (AMA) shows narrow specificity for Zn2+, Ni2+, and Co2+. Here, we show that this specificity allows AMA to block the uptake of Ni2+ and attenuate bacterial Ni-dependent enzymes, offering a potential strategy for reducing virulence. Bacterial exposure to AMA perturbs H2 metabolism, ureolysis, struvite crystallization, and biofilm formation and shows efficacy in a Galleria mellonella animal infection model. The inhibition of Ni-dependent enzymes was aided by Zn2+, which complexes with AMA and competes with the native nickelophore for the uptake of Ni2+. Biochemical analyses demonstrated high-affinity binding of AMA-metal complexes to NikA, the periplasmic substrate-binding protein of the Ni2+ uptake system. Structural examination of NikA in complex with Ni-AMA revealed that the coordination geometry of Ni-AMA mimics the native ligand, Ni-(L-His)2, providing a structural basis for binding AMA-metal complexes. Structure-activity relationship studies of AMA identified regions of the molecule that improve NikA affinity and offer potential routes for further developing this compound as an anti-virulence agent.


Asunto(s)
Proteínas Bacterianas , Níquel , Níquel/metabolismo , Níquel/química , Animales , Virulencia/efectos de los fármacos , Proteínas Bacterianas/metabolismo , Biopelículas/efectos de los fármacos , Zinc/metabolismo , Zinc/química , Mariposas Nocturnas/microbiología , Ureasa/metabolismo , Ureasa/antagonistas & inhibidores , Transporte Biológico
11.
Theor Appl Genet ; 137(6): 122, 2024 May 07.
Artículo en Inglés | MEDLINE | ID: mdl-38713254

RESUMEN

KEY MESSAGE: By deploying a multi-omics approach, we unraveled the mechanisms that might help rice to combat Yellow Stem Borer infestation, thus providing insights and scope for developing YSB resistant rice varieties. Yellow Stem Borer (YSB), Scirpophaga incertulas (Walker) (Lepidoptera: Crambidae), is a major pest of rice, that can lead to 20-60% loss in rice production. Effective management of YSB infestation is challenged by the non-availability of adequate sources of resistance and poor understanding of resistance mechanisms, thus necessitating studies for generating resources to breed YSB resistant rice and to understand rice-YSB interaction. In this study, by using bulk-segregant analysis in combination with next-generation sequencing, Quantitative Trait Loci (QTL) intervals in five rice chromosomes were mapped that could be associated with YSB resistance at the vegetative phase in a resistant rice line named SM92. Further, multiple SNP markers that showed significant association with YSB resistance in rice chromosomes 1, 5, 10, and 12 were developed. RNA-sequencing of the susceptible and resistant lines revealed several genes present in the candidate QTL intervals to be differentially regulated upon YSB infestation. Comparative transcriptome analysis revealed a putative candidate gene that was predicted to encode an alpha-amylase inhibitor. Analysis of the transcriptome and metabolite profiles further revealed a possible link between phenylpropanoid metabolism and YSB resistance. Taken together, our study provides deeper insights into rice-YSB interaction and enhances the understanding of YSB resistance mechanism. Importantly, a promising breeding line and markers for YSB resistance have been developed that can potentially aid in marker-assisted breeding of YSB resistance among elite rice cultivars.


Asunto(s)
Mapeo Cromosómico , Mariposas Nocturnas , Oryza , Sitios de Carácter Cuantitativo , Oryza/genética , Oryza/parasitología , Oryza/inmunología , Animales , Mariposas Nocturnas/fisiología , Polimorfismo de Nucleótido Simple , Enfermedades de las Plantas/parasitología , Enfermedades de las Plantas/genética , Enfermedades de las Plantas/inmunología , Resistencia a la Enfermedad/genética , Genómica/métodos , Fenotipo , Multiómica
12.
Sci Data ; 11(1): 461, 2024 May 06.
Artículo en Inglés | MEDLINE | ID: mdl-38710675

RESUMEN

Oriental tobacco budworm (Helicoverpa assulta) and cotton bollworm (Helicoverpa armigera) are two closely related species within the genus Helicoverpa. They have similar appearances and consistent damage patterns, often leading to confusion. However, the cotton bollworm is a typical polyphagous insect, while the oriental tobacco budworm belongs to the oligophagous insects. In this study, we used Nanopore, PacBio, and Illumina platforms to sequence the genome of H. assulta and used Hifiasm to create a haplotype-resolved draft genome. The Hi-C technique helped anchor 33 primary contigs to 32 chromosomes, including two sex chromosomes, Z and W. The final primary haploid genome assembly was approximately 415.19 Mb in length. BUSCO analysis revealed a high degree of completeness, with 99.0% gene coverage in this genome assembly. The repeat sequences constituted 38.39% of the genome assembly, and we annotated 17093 protein-coding genes. The high-quality genome assembly of the oriental tobacco budworm serves as a valuable genetic resource that enhances our comprehension of how they select hosts in a complex odour environment. It will also aid in developing an effective control policy.


Asunto(s)
Genoma de los Insectos , Haplotipos , Mariposas Nocturnas , Animales , Mariposas Nocturnas/genética , Cromosomas de Insectos , Helicoverpa armigera
13.
Zhonghua Yu Fang Yi Xue Za Zhi ; 58(5): 649-655, 2024 May 06.
Artículo en Chino | MEDLINE | ID: mdl-38715505

RESUMEN

Objective: To evaluate the virulence levels of carbapenem-resistant Acinetobacter baumannii ST191, ST195, and ST208, and to analyze the differences in virulence factors among these epidemic clones. Methods: The study involved the genomic sequencing of 233 Acinetobacter baumannii strains that were isolated from the Fifth Medical Center of the Chinese People's Liberation Army General Hospital (North Hospital) between 2011 and 2019. The genomic data was cross-referenced with the Virulence Factor Database (VFDB) to examine the presence of virulence genes in the strains. Furthermore, a Galleria mellonella infection survival model was used to evaluate the virulence levels of the strains, and the association between virulence levels and virulence genes was analyzed. Results: The study included 38 strains of the ST191 clone, 104 strains of the ST195 clone, and 91 strains of the ST208 clone. In the Galleria mellonella infection survival experiment, the average mortality rate for ST191 was 23.0%, with 3 (7.9%) highly virulent strains. For ST195, the average mortality rate was 53.0%, with 34 (32.7%) highly virulent strains. For ST208, the average mortality rate was 47.0%, with 20 (21.9%) highly virulent strains. There was a significant statistical difference in mortality rates between ST191 and ST195 (χ2=13.9, P<0.001) as well as between ST191 and ST208 (χ2=15.2, P<0.001). A comparison of the strains with the VFDB revealed significant differences in the virulence genes carried by the clones. Specifically, the type Ⅵ secretion system-related genes (clpV/tssH, hcp/tssD, tagX, tssA, tssB, tssC, tssE, tssF, tssG, tssK, ssL, tssM) and the sugar transferase gene ACICU_RS00475 were found to be universally absent in ST191 strains (0%) while being prevalent in ST195 (100.0%) and ST208 (>82.0%) strains. Statistical analysis revealed an association between the mortality rate of the clones and the presence of virulence genes(clpV/tssH P<0.001, hcp/tssD P=0.001, tagX P<0.001, tssA P<0.001, tssB P=0.001, tssC P=0.001, tssE P=0.001, tssF P=0.001, tssG P<0.001, tssK P<0.001, tssL P<0.001, tssM P=0.001, ACICU_RS00475 P=0.001). Conclusion: Among the carbapenem-resistant epidemic clones of Acinetobacter baumannii, the ST191 clone shows lower mortality rates in Galleria mellonella, possibly because of the lack of type Ⅵ secretion system and sugar transferase genes.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Carbapenémicos , Factores de Virulencia , Acinetobacter baumannii/genética , Acinetobacter baumannii/patogenicidad , Carbapenémicos/farmacología , Virulencia/genética , Infecciones por Acinetobacter/microbiología , Infecciones por Acinetobacter/epidemiología , Factores de Virulencia/genética , Animales , Mariposas Nocturnas/microbiología , Antibacterianos/farmacología , Humanos , Farmacorresistencia Bacteriana
14.
PLoS One ; 19(5): e0302941, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38709777

RESUMEN

Insecticidal Bacillus thuringiensis Berliner (Bt) toxins produced by transgenic cotton (Gossypium hirsutum L.) plants have become an essential component of cotton pest management. Bt toxins are the primary management tool in transgenic cotton for lepidopteran pests, the most important of which is the bollworm (Helicoverpa zea Boddie) (Lepidoptera: Noctuidae) in the United States (U.S.). However, bollworm larvae that survive after consuming Bt toxins may experience sublethal effects, which could alter interactions with other organisms, such as natural enemies. Experiments were conducted to evaluate how sublethal effects of a commercial Bt product (Dipel) incorporated into artificial diet and from Bt cotton flowers impact predation from the convergent lady beetle (Hippodamia convergens Guérin-Méneville) (Coleoptera: Coccinellidae), common in cotton fields of the mid-southern U.S. Sublethal effects were detected through reduced weight and slower development in bollworm larvae which fed on Dipel incorporated into artificial diet, Bollgard II, and Bollgard 3 cotton flowers. Sublethal effects from proteins incorporated into artificial diet were found to significantly alter predation from third instar lady beetle larvae. Predation of bollworm larvae also increased significantly after feeding for three days on a diet incorporated with Bt proteins. These results suggest that the changes in larval weight and development induced by Bt can be used to help predict consumption of bollworm larvae by the convergent lady beetle. These findings are essential to understanding the potential level of biological control in Bt cotton where lepidopteran larvae experience sublethal effects.


Asunto(s)
Bacillus thuringiensis , Escarabajos , Flores , Gossypium , Larva , Plantas Modificadas Genéticamente , Conducta Predatoria , Animales , Escarabajos/efectos de los fármacos , Escarabajos/fisiología , Gossypium/parasitología , Gossypium/genética , Conducta Predatoria/efectos de los fármacos , Larva/efectos de los fármacos , Control Biológico de Vectores , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/fisiología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Toxinas de Bacillus thuringiensis
15.
Front Cell Infect Microbiol ; 14: 1382145, 2024.
Artículo en Inglés | MEDLINE | ID: mdl-38736748

RESUMEN

Carbapenem-resistant Acinetobacter baumannii (CRAB) has become a new threat in recent years, owing to its rapidly increasing resistance to antibiotics and new effective therapies are needed to combat this pathogen. Phage therapy is considered to be the most promising alternative for treating CRAB infections. In this study, a novel phage, Ab_WF01, which can lyse clinical CRAB, was isolated and characterized from hospital sewage. The multiplicity of infection, morphology, one-step growth curve, stability, sensitivity, and lytic activity of the phage were also investigated. The genome of phage Ab_WF01 was 41, 317 bp in size with a GC content of 39.12% and encoded 51 open reading frames (ORFs). tRNA, virulence, and antibiotic resistance genes were not detected in the phage genome. Comparative genomic and phylogenetic analyses suggest that phage Ab_WF01 is a novel species of the genus Friunavirus, subfamily Beijerinckvirinae, and family Autographiviridae. The in vivo results showed that phage Ab_WF01 significantly increased the survival rate of CRAB-infected Galleria mellonella (from 0% to 70% at 48 h) and mice (from 0% to 60% for 7 days). Moreover, after day 3 post-infection, phage Ab_WF01 reduced inflammatory response, with strongly ameliorated histological damage and bacterial clearance in infected tissue organs (lungs, liver, and spleen) in mouse CRAB infection model. Taken together, these results show that phage Ab_WF01 holds great promise as a potential alternative agent with excellent stability for against CRAB infections.


Asunto(s)
Infecciones por Acinetobacter , Acinetobacter baumannii , Bacteriófagos , Carbapenémicos , Genoma Viral , Terapia de Fagos , Filogenia , Aguas del Alcantarillado , Acinetobacter baumannii/virología , Acinetobacter baumannii/efectos de los fármacos , Aguas del Alcantarillado/virología , Aguas del Alcantarillado/microbiología , Animales , Carbapenémicos/farmacología , Bacteriófagos/genética , Bacteriófagos/fisiología , Bacteriófagos/clasificación , Bacteriófagos/aislamiento & purificación , Infecciones por Acinetobacter/microbiología , Ratones , Antibacterianos/farmacología , Sistemas de Lectura Abierta , Modelos Animales de Enfermedad , Mariposas Nocturnas/virología , Mariposas Nocturnas/microbiología , Composición de Base
16.
Glob Chang Biol ; 30(5): e17294, 2024 May.
Artículo en Inglés | MEDLINE | ID: mdl-38738554

RESUMEN

The potential for climate change to disrupt phenology-mediated interactions in interaction networks has attracted considerable attention in recent decades. Frequently, studies emphasize the fragility of ephemeral seasonal interactions, and the risks posed by phenological asynchrony. Here, we argue that the fitness consequences of asynchrony in phenological interactions may often be more buffered than is typically acknowledged. We identify three main forms that buffering may take: (i) mechanisms that reduce asynchrony between consumer and resource; (ii) mechanisms that reduce the costs of being asynchronous; and (iii) mechanisms that dampen interannual variance in performance across higher organizational units. Using synchrony between the hatching of winter moth caterpillars and the leafing of their host-plants as a case study, we identify a wide variety of buffers that reduce the detrimental consequences of phenological asynchrony on caterpillar individuals, populations, and meta-populations. We follow this by drawing on examples across a breadth of taxa, and demonstrate that these buffering mechanisms may be quite general. We conclude by identifying key gaps in our knowledge of the fitness and demographic consequences of buffering, in the context of phenological mismatch. Buffering has the potential to substantially alter our understanding of the biotic impacts of future climate change-a greater recognition of the contribution of these mechanisms may reveal that many trophic interactions are surprisingly resilient, and also serve to shift research emphasis to those systems with fewer buffers and towards identifying the limits of those buffers.


Asunto(s)
Cambio Climático , Mariposas Nocturnas , Animales , Mariposas Nocturnas/fisiología , Larva/fisiología , Larva/crecimiento & desarrollo , Estaciones del Año , Hojas de la Planta/crecimiento & desarrollo , Hojas de la Planta/fisiología
17.
Molecules ; 29(9)2024 May 04.
Artículo en Inglés | MEDLINE | ID: mdl-38731627

RESUMEN

A concise synthesis of the sex pheromones of elm spanworm as well as painted apple moth has been achieved. The key steps were the alkylation of acetylide ion, Sharpless asymmetric epoxidation and Brown's P2-Ni reduction. This approach provided the sex pheromone of the elm spanworm (1) in 31% total yield and those of the painted apple moth (2, 3) in 26% and 32% total yields. The ee values of three final products were up to 99%. The synthesized pheromones hold promising potential for use in the management and control of these pests.


Asunto(s)
Compuestos Epoxi , Mariposas Nocturnas , Atractivos Sexuales , Animales , Atractivos Sexuales/síntesis química , Atractivos Sexuales/química , Compuestos Epoxi/química , Estructura Molecular
18.
Mol Immunol ; 170: 76-87, 2024 Jun.
Artículo en Inglés | MEDLINE | ID: mdl-38640818

RESUMEN

Peroxiredoxins are antioxidant proteins that detoxify peroxynitrite, hydrogen peroxide, and organic hydroperoxides, impacting various physiological processes such as immune responses, apoptosis, cellular homeostasis, and so on. In the present study, we identified and characterized peroxiredoxin 1 from Antheraea pernyi (thereafter designated as ApPrx-1) that encodes a predicted 195 amino acid residue protein with a 21.8 kDa molecular weight. Quantitative real-time PCR analysis revealed that the mRNA level of ApPrx-1 was highest in the hemocyte, fat body, and midgut. Immune-challenged larval fat bodies and hemocytes showed increased ApPrx-1 transcript. Moreover, ApPrx-1 expression was induced in hemocytes and the whole body of A. pernyi following exogenous H2O2 administration. A DNA cleavage assay performed using recombinant ApPrx-1 protein showed that rApPrx-1 protein manifests the ability to protect supercoiled DNA damage from oxidative stress. To test the rApPrx-1 protein antioxidant activity, the ability of the rApPrx-1 protein to remove H2O2 was assessed in vitro using rApPrx-1 protein and DTT, while BSA + DDT served as a control group. The results revealed that ApPrx-1 can efficiently remove H2O2 in vitro. In the loss of function analysis, we found that ApPrx-1 significantly increased the levels of H2O2 in ApPrx-1-depleted larvae compared to the control group. We also found a significantly lower survival rate in the larvae in which ApPrx-1 was knocked down. Interestingly, the antibacterial activity was significantly higher in the ApPrx-1 depleted larvae, compared to the control. Collectively, evidence strongly suggests that ApPrx-1 may regulate physiological activities and provides a reference for further studies to validate the utility of the key genes involved in reliving oxidative stress conditions and regulating the immune responses of insects.


Asunto(s)
Hemocitos , Peróxido de Hidrógeno , Mariposas Nocturnas , Estrés Oxidativo , Peroxirredoxinas , Animales , Peroxirredoxinas/genética , Peroxirredoxinas/metabolismo , Peroxirredoxinas/inmunología , Mariposas Nocturnas/inmunología , Mariposas Nocturnas/genética , Estrés Oxidativo/genética , Peróxido de Hidrógeno/farmacología , Hemocitos/metabolismo , Hemocitos/inmunología , Proteínas de Insectos/genética , Proteínas de Insectos/metabolismo , Larva/genética , Antioxidantes/metabolismo , Secuencia de Aminoácidos , Daño del ADN
19.
Cell Rep ; 43(4): 114082, 2024 Apr 23.
Artículo en Inglés | MEDLINE | ID: mdl-38583155

RESUMEN

Infections caused by methicillin-resistant Staphylococcus aureus (MRSA) are alarmingly common, and treatment is confined to last-line antibiotics. Vancomycin is the treatment of choice for MRSA bacteremia, and treatment failure is often associated with vancomycin-intermediate S. aureus isolates. The regulatory 3' UTR of the vigR mRNA contributes to vancomycin tolerance and upregulates the autolysin IsaA. Using MS2-affinity purification coupled with RNA sequencing, we find that the vigR 3' UTR also regulates dapE, a succinyl-diaminopimelate desuccinylase required for lysine and peptidoglycan synthesis, suggesting a broader role in controlling cell wall metabolism and vancomycin tolerance. Deletion of the 3' UTR increased virulence, while the isaA mutant is completely attenuated in a wax moth larvae model. Sequence and structural analyses of vigR indicated that the 3' UTR has expanded through the acquisition of Staphylococcus aureus repeat insertions that contribute sequence for the isaA interaction seed and may functionalize the 3' UTR.


Asunto(s)
Regiones no Traducidas 3' , Infecciones Estafilocócicas , Staphylococcus aureus , Animales , Regiones no Traducidas 3'/genética , Antibacterianos/farmacología , Proteínas Bacterianas/genética , Proteínas Bacterianas/metabolismo , Secuencia de Bases , Regulación Bacteriana de la Expresión Génica , Staphylococcus aureus Resistente a Meticilina/genética , Staphylococcus aureus Resistente a Meticilina/patogenicidad , Staphylococcus aureus Resistente a Meticilina/efectos de los fármacos , Mariposas Nocturnas/microbiología , Infecciones Estafilocócicas/microbiología , Infecciones Estafilocócicas/tratamiento farmacológico , Staphylococcus aureus/genética , Staphylococcus aureus/patogenicidad , Staphylococcus aureus/efectos de los fármacos , Vancomicina/farmacología , Virulencia/genética
20.
Sci Rep ; 14(1): 9299, 2024 04 23.
Artículo en Inglés | MEDLINE | ID: mdl-38653843

RESUMEN

Phthorimaea absoluta is a global constraint to tomato production and can cause up to 100% yield loss. Farmers heavily rely on synthetic pesticides to manage this pest. However, these pesticides are detrimental to human, animal, and environmental health. Therefore, exploring eco-friendly, sustainable Integrated Pest Management approaches, including biopesticides as potential alternatives, is of paramount importance. In this context, the present study (i) evaluated the efficacy of 10 Bacillus thuringiensis isolates, neem, garlic, and fenugreek; (ii) assessed the interactions between the most potent plant extracts and B. thuringiensis isolates, and (iii) evaluated the gut microbial diversity due to the treatments for the development of novel formulations against P. absoluta. Neem recorded the highest mortality of 93.79 ± 3.12% with an LT50 value of 1.21 ± 0.24 days, Bt HD263 induced 91.3 ± 3.68% mortality with LT50 of 2.63 ± 0.11 days, compared to both Bt 43 and fenugreek that caused < 50% mortality. Larval mortality was further enhanced to 99 ± 1.04% when Bt HD263 and neem were combined. Furthermore, the microbiome analyses showed that Klebsiella, Escherichia and Enterobacter had the highest abundance in all treatments with Klebsiella being the most abundant. In addition, a shift in the abundance of the bacterial genera due to the treatments was observed. Our findings showed that neem, garlic, and Bt HD263 could effectively control P. absoluta and be integrated into IPM programs after validation by field efficacy trials.


Asunto(s)
Bacillus thuringiensis , Extractos Vegetales , Trigonella , Animales , Extractos Vegetales/farmacología , Extractos Vegetales/química , Trigonella/química , Control Biológico de Vectores/métodos , Mariposas Nocturnas/efectos de los fármacos , Mariposas Nocturnas/microbiología , Larva/efectos de los fármacos , Larva/microbiología , Ajo/química , Microbioma Gastrointestinal/efectos de los fármacos , Solanum lycopersicum/microbiología
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