UCE-based phylogenomics of the lepidopteran endoparasitoid wasp subfamily Rogadinae (Hymenoptera: Braconidae) unveils a new Neotropical tribe.

During the past two decades, the phylogenetic relationships and higher-level classification of the subfamily Rogadinae have received relevant contributions based on Sanger, mitogenome and genome-wide nuclear DNA sequence data. These studies have helped to update the circumscription and tribal classification of this subfamily, with six tribes currently recognised (Aleiodini, Betylobraconini, Clinocentrini, Rogadini, Stiropiini and Yeliconini). The tribal relationships within Rogadinae, however, are yet to be fully resolved, including the status of tribe Facitorini, previously regarded as betylobraconine, with respect to the members of Yeliconini. We conducted a phylogenomic analysis among the tribes of Rogadinae based on genomic ultraconserved element (UCE) data and extensive taxon sampling including three undescribed genera of uncertain tribal placement. Our almost fully supported estimate of phylogeny confirmed the basal position of Rogadini within the subfamily and a Facitorini clade (Yeliconini+Aleiodini) that led us to propose the former group as a valid rogadine tribe (Facitorini stat. res.). Stiropiini, however, was recovered for the first time as sister to the remaining rogadine tribes except Rogadini, and Clinocentrini as sister to a clade with Betylobraconini+the three undescribed genera. The relationships recovered and morphological examination of the material included led us to place the latter three new genera and recently described genus Gondwanocentrus within a new rogadine tribe, Gondwanocentrini Shimbori & Zaldívar-Riverón trib. nov. We described these genera (Ghibli Shimbori & Zaldívar-Riverón gen. nov., Racionais Shimbori & Zaldívar-Riverón gen. nov. and Soraya Shimbori gen. nov.) with two or three new species each (G. miyazakii Shimbori & Zaldívar-Riverón sp. nov., G. totoro Shimbori & Zaldívar-Riverón sp. nov., R. brunus Shimbori & Zaldívar-Riverón sp. nov., R. kaelejay Shimbori & Zaldívar-Riverón sp. nov., R. superstes Shimbori & Zaldívar-Riverón sp. nov., S. alencarae Shimbori sp. nov. and S. venus Shimbori & Zaldívar-Riverón sp. nov.). A new species of Facitorini, Jannya pasargadae Gadelha & Shimbori sp. nov., is also described. Our newly proposed classification expands the number of tribes and genera within Rogadinae to 8 and 66 respectively. ZooBank: urn:lsid:zoobank.org:pub:51951C78-069A-4D8B-B5F0-7EBD4D9D21CE.

Anti-virulence potential of iclaprim, a novel folic acid synthesis inhibitor, against Staphylococcus aureus.

Infections caused by Staphylococcus aureus pose a significant global public problem. Therefore, new antibiotics and therapeutic strategies are needed to combat this pathogen. This investigation delves into the effects of iclaprim, a newly discovered inhibitor of folic acid synthesis, on S. aureus virulence. The phenotypic and genotypic effects of iclaprim were thoroughly examined in relation to virulence factors, biofilm formation, and dispersal, as well as partial virulence-encoding genes associated with exoproteins, adherence, and regulation in S. aureus MW2, N315, and ATCC 25923. Then, the in vivo effectiveness of iclaprim on S. aureus pathogenicity was explored by a Galleria mellonella larvae infection model. The use of iclaprim at sub-inhibitory concentrations (sub-MICs) resulted in a reduction of α-hemolysin (Hla) production and a differential effect on the activity of coagulase in S. aureus strains. The results of biofilm formation and eradication assay showed that iclaprim was highly effective in depolymerizing the mature biofilm of S. aureus strains at concentrations of 1 MIC or greater, however, inhibited the biofilm-forming ability of only strains N315 and ATCC 25923 at sub-MICs. Interestingly, treatment of strains with sub-MICs of iclaprim resulted in significant stimulation or suppression of most virulence-encoding genes expression. Iclaprim did not affect the production of δ-hemolysin or staphylococcal protein A (SpA), nor did it impact the total activity of proteases, nucleases, and lipases. In vivo testing showed that sub-MICs of iclaprim significantly improves infected larvae survival. The present study offered valuable insights towards a better understating of the influence of iclaprim on different strains of S. aureus. The findings suggest that iclaprim may have potential as an anti-virulence and antibiofilm agent, thus potentially mitigating the pathogenicity of S. aureus and improving clinical outcomes associated with infections caused by this pathogen. KEY POINTS: • Iclaprim effectively inhibits α-hemolysin production and biofilm formation in a strain-dependent manner and was an excellent depolymerizing agent of mature biofilm • Iclaprim affected the mRNA expression of virulence-encoding genes associated with exoproteins, adherence, and regulation • In vivo study in G. mellonella larvae challenged with S. aureus exhibited that iclaprim improves larvae survival.

A synthetic peptide mimic kills Candida albicans and synergistically prevents infection.

More than two million people worldwide are affected by life-threatening, invasive fungal infections annually. Candida species are the most common cause of nosocomial, invasive fungal infections and are associated with mortality rates above 40%. Despite the increasing incidence of drug-resistance, the development of novel antifungal formulations has been limited. Here we investigate the antifungal mode of action and therapeutic potential of positively charged, synthetic peptide mimics to combat Candida albicans infections. Our data indicates that these synthetic polymers cause endoplasmic reticulum stress and affect protein glycosylation, a mode of action distinct from currently approved antifungal drugs. The most promising polymer composition damaged the mannan layer of the cell wall, with additional membrane-disrupting activity. The synergistic combination of the polymer with caspofungin prevented infection of human epithelial cells in vitro, improved fungal clearance by human macrophages, and significantly increased host survival in a Galleria mellonella model of systemic candidiasis. Additionally, prolonged exposure of C. albicans to the synergistic combination of polymer and caspofungin did not lead to the evolution of tolerant strains in vitro. Together, this work highlights the enormous potential of these synthetic peptide mimics to be used as novel antifungal formulations as well as adjunctive antifungal therapy.

Comparative Proteomics and Metabonomics Analysis of Different Diapause Stages Revealed a New Regulation Mechanism of Diapause in Loxostege sticticalis (Lepidoptera: Pyralidae).

Histone acetylation is an important epigenetic mechanism that has been shown to play a role in diapause regulation. To explore the physiological and molecular mechanisms of histone deacetylase in the diapause process, LC-MS/MS analysis was used to perform TMT proteomic and metabolomic analysis on non-diapause (ND), pre-diapause (PreD), diapause (D), cold treatment (CT), and post-diapause (RD) stages of the meadow moth. A total of 5367 proteins were identified by proteomics, including 1179 differentially expressed proteins. We found 975 (602 up-regulated and 373 down-regulated), 997 (608 up-regulated and 389 down-regulated), 1119 (726 up-regulated and 393 down-regulated), 1179 (630 up-regulated and 549 down-regulated), 94 (51 up-regulated and 43 down-regulated), 111 (63 up-regulated and 48 down-regulated), 533 (243 up-regulated and 290 down-regulated), 58 (31 up-regulated and 27 down-regulated), and 516 (228 up-regulated and 288 down-regulated) proteins in ND and PreD, ND and D, ND and CT, ND and RD, PreD and D, PreD and CT, PreD and RD, D and CT, D and RD, and CT and RD stages, respectively. A total of 1255 differentially expressed metabolites were annotated by metabolomics. Through KEGG analysis and time series analysis of differentially expressed metabolites, we found that phospholipids were annotated in significantly different modules, demonstrating their important role in the diapause process of the meadow moth. Using phospholipids as an indicator for weighted gene co-expression network analysis, we analyzed the most relevant differentially expressed proteins in the module and found that ribosomal 40s and 60s subunits were the most relevant proteins for diapause. Because there have been studies that have shown that histone deacetylase is associated with the diapause of meadow moths, we believe that histone deacetylase regulates the 40s and 60s subunits of ribosomes, which in turn affects the diapause of meadow moths. This finding expands our understanding of the regulation of meadow moth diapause and provides new insights into its control mechanism.

Antimicrobial Evaluation of Two Polycyclic Polyprenylated Acylphloroglucinol Compounds: PPAP23 and PPAP53.

Polycyclic polyprenylated acylphloroglucinols (PPAPs) comprise a large group of compounds of mostly plant origin. The best-known compound is hyperforin from St. John's wort with its antidepressant, antitumor and antimicrobial properties. The chemical synthesis of PPAP variants allows the generation of compounds with improved activity and compatibility. Here, we studied the antimicrobial activity of two synthetic PPAP-derivatives, the water-insoluble PPAP23 and the water-soluble sodium salt PPAP53. In vitro, both compounds exhibited good activity against methicillin-resistant Staphylococcus aureus (MRSA) and vancomycin-resistant Enterococcus faecium. Both compounds had no adverse effects on Galleria mellonella wax moth larvae. However, they were unable to protect the larvae from infection with S. aureus because components of the larval coelom neutralized the antimicrobial activity; a similar effect was also seen with serum albumin. In silico docking studies with PPAP53 revealed that it binds to the F1 pocket of human serum albumin with a binding energy of -7.5 kcal/mol. In an infection model of septic arthritis, PPAP23 decreased the formation of abscesses and S. aureus load in kidneys; in a mouse skin abscess model, topical treatment with PPAP53 reduced S. aureus counts. Both PPAPs were active against anaerobic Gram-positive gut bacteria such as neurotransmitter-producing Clostridium, Enterococcus or Ruminococcus species. Based on these results, we foresee possible applications in the decolonization of pathogens.

Gut Microbiota Mediate Plutella xylostella Susceptibility to Bt Cry1Ac Protoxin and Exopolysaccharides.

Exopolysaccharides (EPSs) are carbohydrate polymers that are synthesized and secreted into the extracellular during the growth of microorganisms. Bacillus thuringiensis (Bt) is a type of entomopathogenic bacterium, that produces various insecticidal proteins and EPSs. In our previous study, the EPSs produced by Bt strains were first found to enhance the toxicity of insecticidal crystal proteins against Plutella xylostella. However, the response of the intestinal bacterial communities of P. xylostella under the action of EPSs is still unelucidated. In this study, 16S rRNA amplicon sequencing was used to characterize the intestinal bacterial communities in P. xylostella treated with EPSs alone, Cry1Ac protoxin alone, and both the Cry1Ac protoxin and EPSs. Compared with the control group, alpha diversity indices, the Chao1 and ACE indices were significantly altered after treatment with EPSs alone, and no significant difference was observed between the groups treated with Cry1Ac protoxin alone and Cry1Ac protoxin + EPSs. However, compared with the gut bacterial community feeding on Cry1Ac protoxin alone, the relative abundance of 31 genera was significantly changed in the group treated with Cry1Ac protoxin and EPSs. The intestinal bacteria, through the oral of Cry1Ac protoxin and EPSs, significantly enhanced the toxicity of the Cry1Ac protoxin towards the axenic P. xylostella. In addition, the relative abundance of the 16S rRNA gene in the chloroplasts of Brassica campestris decreased after adding EPSs. Taken together, these results show the vital contribution of the gut microbiota to the Bt strain-killing activity, providing new insights into the mechanism of the synergistic insecticidal activity of Bt proteins and EPSs.

Death-Associated LIM-Only Protein Reduces Cry1Ac Toxicity by Sequestration of Cry1Ac Protoxin and Activated Toxin in Helicoverpa armigera.

The extensive use of Bacillus thuringiensis (Bt) in pest management has driven the evolution of pest resistance to Bt toxins, particularly Cry1Ac. Effective management of Bt resistance necessitates a good understanding of which pest proteins interact with Bt toxins. In this study, we screened a Helicoverpa armigera larval midgut cDNA library and captured 208 potential Cry1Ac-interacting proteins. Among these, we further examined the interaction between Cry1Ac and a previously unknown Cry1Ac-interacting protein, HaDALP (H. armigera death-associated LIM-only protein), as well as its role in toxicology. The results revealed that HaDALP specifically binds to both the Cry1Ac protoxin and activated toxin, significantly enhancing cell and larval tolerance to Cry1Ac. Additionally, HaDALP was overexpressed in a Cry1Ac-resistant H. armigera strain. These findings reveal a greater number of Cry1Ac-interacting proteins than previously known and demonstrate, for the first time, that HaDALP reduces Cry1Ac toxicity by sequestering both the protoxin and activated toxin.

Functional Characterization of Peripheral Neurons and a Receptor Recognizing Sex Pheromones in Hyphantria cunea (Erebidae).

Hyphantria cunea (Lepidoptera: Erebidae) is difficult and costly to control as a quarantine pest found globally. Sex pheromone trapping is an effective measure for its population monitoring and control; however, the peripheral neural mechanism of sex pheromone recognition in H. cunea remains unclear. An electrophysiological analysis showed that both male and female moths of H. cunea responded to four components of sex pheromones and the responses of male moths were stronger than those of the female moths. We identified three types of trichoid sensilla (ST) responsive to sex pheromones using the single sensillum recording technique. Each type was involved in recognizing 9R, 10S-epoxy-1, Z3, Z6-heneicosatriene (1, Z3, Z6-9S, 10R-epoxy-21Hy). Four peripheral neurons involved in the olfactory encoding of sex pheromones were identified. Four candidate pheromone receptor (PR) genes, HcunPR1a, HcunPR1b, HcunPR3, and HcunPR4, were screened by transcriptome sequencing. All of them were highly expressed in the antennae of males, except for HcunPR4, which was highly expressed in the antennae of females. Functional identification showed that HcunPR1a responded to sex pheromone. Other HcunPRs were not functionally identified. In summary, neurons involved in sex pheromone recognition of H. cunea were located in the ST, and HcunPR1a recognized secondary pheromone components 1, Z3, Z6-9S, 10R-epoxy-21Hy. Interestingly, PRs that recognize the main components of the sex pheromone may be located in an unknown branch of the olfactory receptor and merit further study. Our findings provide a better understanding of the peripheral neural coding mechanism of type II sex pheromones, and HcunPR1a may provide a target for the subsequent development of highly effective and specific biopesticides for H. cunea.

Fitness costs, realized heritability, and mechanism of resistance to tenvermectin B in Plutella xylostella.

Tenvermectin B (TVM-B) and five TVM-B analogs were produced by fermentation of a genetically engineered strain Streptomyces avermitilis HU02, and TVM-B is being developed as a new insecticide. Through 11 generations of resistance selection against TVM-B in the diamondback moth, Plutella xylostella, the median lethal concentration (LC50) was increased from 14.84 to 1213.73 mg L-1. The resistance to TVM-B in P. xylostella developed fast and its realized heritability was high (h2 = 0.2901 (F7), h2 = 0.4070 (F11)). However, the relative fitness was 0.6916 suggesting a fitness cost in the resistant strains. The fitness cost was partially explained by the upregulation of the detoxification enzyme activity by 2.15 folds in carboxylate esterase (CarE) and the gene expressions of ATP-binding cassette transporter gene (ABCC2) and the alpha subunit of the glutamate-gated chloride channel (GluCl) by 1.70- and 2.32 folds, respectively. The resistance was also explained by two points of mutations at the alpha subunit of the glutamate-gated chloride channel in the P. xylostella (PxGluClα) subunit in F11. However, there was little change in the binding affinity. These results provided helpful information for the mechanism study of TVM-B resistance and will be conducive to designing rational resistance management strategies in P. xylostella.

Phylogenetic structure of moth communities (Geometridae, Lepidoptera) along a complete rainforest elevational gradient in Papua New Guinea.

We use community phylogenetics to elucidate the community assembly mechanisms for Geometridae moths (Lepidoptera) collected along a complete rainforest elevational gradient (200-3700 m a.s.l) on Mount Wilhelm in Papua New Guinea. A constrained phylogeny based on COI barcodes for 604 species was used to analyse 1390 species x elevation occurrences at eight elevational sites separated by 500 m elevation increments. We obtained Nearest Relatedness Index (NRI), Nearest Taxon Index (NTI) and Standardised Effect Size of Faith's Phylogenetic Diversity (SES.PD) and regressed these on temperature, plant species richness and predator abundance as key abiotic and biotic predictors. We also quantified beta diversity in the moth communities between elevations using the Phylogenetic Sorensen index. Overall, geometrid communities exhibited phylogenetic clustering, suggesting environmental filters, particularly at higher elevations at and above 2200 m a.s.l and no evidence of overdispersion. NRI, NTI and SES.PD showed no consistent trends with elevation or the studied biotic and abiotic variables. Change in community structure was driven by turnover of phylogenetic beta-diversity, except for the highest 2700-3200 m elevations, which were characterised by nested subsets of lower elevation communities. Overall, the elevational signal of geometrid phylogeny was weak-moderate. Additional insect community phylogeny studies are needed to understand this pattern.

Lipases are differentially regulated by hormones to maintain free fatty acid homeostasis for insect brain development.

BACKGROUND: Free fatty acids (FFAs) play vital roles as energy sources and substrates in organisms; however, the molecular mechanism regulating the homeostasis of FFA levels in various circumstances, such as feeding and nonfeeding stages, is not fully clarified. Holometabolous insects digest dietary triglycerides (TAGs) during larval feeding stages and degrade stored TAGs in the fat body during metamorphosis after feeding cessation, which presents a suitable model for this study. RESULTS: This study reported that two lipases are differentially regulated by hormones to maintain the homeostasis of FFA levels during the feeding and nonfeeding stages using the lepidopteran insect cotton bollworm Helicoverpa armigera as a model. Lipase member H-A-like (Lha-like), related to human pancreatic lipase (PTL), was abundantly expressed in the midgut during the feeding stage, while the monoacylglycerol lipase ABHD12-like (Abhd12-like), related to human monoacylglycerol lipase (MGL), was abundantly expressed in the fat body during the nonfeeding stage. Lha-like was upregulated by juvenile hormone (JH) via the JH intracellular receptor methoprene-tolerant 1 (MET1), and Abhd12-like was upregulated by 20-hydroxyecdysone (20E) via forkhead box O (FOXO) transcription factor. Knockdown of Lha-like decreased FFA levels in the hemolymph and reduced TAG levels in the fat body. Moreover, lipid droplets (LDs) were small, the brain morphology was abnormal, the size of the brain was small, and the larvae showed the phenotype of delayed pupation, small pupae, and delayed tissue remodeling. Knockdown of Abhd12-like decreased FFA levels in the hemolymph; however, TAG levels increased in the fat body, and LDs remained large. The development of the brain was arrested at the larval stage, and the larvae showed a delayed pupation phenotype and delayed tissue remodeling. CONCLUSIONS: The differential regulation of lipases expression by different hormones determines FFAs homeostasis and different TAG levels in the fat body during the feeding larval growth and nonfeeding stages of metamorphosis in the insect. The homeostasis of FFAs supports insect growth, brain development, and metamorphosis.

Genes required for phosphosphingolipid formation in Caulobacter crescentus contribute to bacterial virulence.

Sphingolipids are ubiquitous in membranes of eukaryotes and are associated with important cellular functions. Although sphingolipids occur scarcely in bacteria, for some of them they are essential and, in other bacteria, they contribute to fitness and stability of the outer membrane, such as in the well-studied α-proteobacterium Caulobacter crescentus. We previously defined five structural genes for ceramide synthesis in C. crescentus, among them the gene for serine palmitoyltransferase, the enzyme that catalyzes the committed step of sphingolipid biosynthesis. Other mutants affected in genes of this same genomic region show cofitness with a mutant deficient in serine palmitoyltransferase. Here we show that at least two phosphosphingolipids are produced in C. crescentus and that at least another six gene products are needed for the decoration of ceramide upon phosphosphingolipid formation. All eleven genes participating in phosphosphingolipid formation are also required in C. crescentus for membrane stability and for displaying sensitivity towards the antibiotic polymyxin B. The genes for the formation of complex phosphosphingolipids are also required for C. crescentus virulence on Galleria mellonella insect larvae.

A First-in-Class Pyrazole-isoxazole Enhanced Antifungal Activity of Voriconazole: Synergy Studies in an Azole-Resistant Candida albicans Strain, Computational Investigation and in Vivo Validation in a Galleria mellonella Fungal Infection Model.

The widespread and irrational use of azole antifungal agents has led to an increase of azole-resistant Candida albicans strains with an urgent need for combination drug therapy, enhancing the treatment efficacy. Here, we report the discovery of a first-in-class pyrazole-isoxazole, namely, 5b, that showed remarkable growth inhibition against the C. albicans ATCC 10231 strain in combination with voriconazole, acting as a downregulator of ERG 11 (Cyp51) gene expression with a significant reduction of the yeast-to-hypha morphological transition. Furthermore, C. albicans CYP51 enzyme assay and in-depth molecular docking studies unveiled the unique ability of the combination of 5b and voriconazole to completely fill the CYP51 binding sites. In vivo studies using a Galleria mellonella model confirmed the previously in vitro observed synergistic effect of 5b with voriconazole. Also considering its biocompatibility in a cellular model of human keratinocytes, these results indicate that 5b represents a promising compound for a further optimization campaign.

Experimental evidence of a Neotropical pest insect moderately tolerant to complete freezing.

Due to climate change, many regions are experiencing progressively milder winters. Consequently, pest insects from warm regions, particularly those with some tolerance to low temperatures, could expand their geographic range into these traditionally colder regions. The palm borer moth (Paysandisia archon) is a Neotropical insect that in recent decades has reached Europe and Asia as one of the worst pests of palm trees. Little is known about its ability to tolerate moderately cold winters and, therefore, to colonize new areas. In this work, we characterized the cold tolerance of Paysandisia archon by measuring its thermal limits: median lethal-temperature, LT50, chill-coma onset temperature, CTmin, supercooling point, SCP, freezing time and freezing survival. We found that this species was able to survive short periods of complete freezing, with survival rates of 87% after a 30-min freezing exposure, and 33% for a 1 h-exposure. It is then a moderately freeze-tolerant species, in contrast to all other lepidopterans native to warm areas, which are freeze-intolerant. Additionally, we investigated whether this insect improved its cold tolerance after either short or long pre-exposure to sub-lethal low temperatures. To that end, we studied potential changes in the main thermo-tolerance parameters and, using X-ray Computed Tomography, also in the morphological components of pretreated animals. We found that short pre-exposures did not imply significant changes in the SCP and CTmin values. In contrast, larvae with long pretreatments improved their survival to both freezing and low temperatures, and required longer times for complete freezing than the other groups. These long-term pre-exposed larvae also presented several morphological changes, including a reduction in water content that probably explained, at least in part, their longer freezing time and higher freezing survival. Our results represent the first cold tolerance characterization of this pest insect, which could be relevant to better design strategies to combat it.

CRY1 is involved in the take-off behaviour of migratory Cnaphalocrocis medinalis individuals.

BACKGROUND: Numerous insect species undertake long-distance migrations on an enormous scale, with great implications for ecosystems. Given that take-off is the point where it all starts, whether and how the external light and internal circadian rhythm are involved in regulating the take-off behaviour remains largely unknown. Herein, we explore this issue in a migratory pest, Cnaphalocrocis medinalis, via behavioural observations and RNAi experiments. RESULTS: The results showed that C. medinalis moths took off under conditions where the light intensity gradually weakened to 0.1 lx during the afternoon or evening, and the take-off proportions under full spectrum or blue light were significantly higher than that under red and green light. The ultraviolet-A/blue light-sensitive type 1 cryptochrome gene (Cmedcry1) was significantly higher in take-off moths than that of non-take-off moths. In contrast, the expression of the light-insensitive CRY2 (Cmedcry2) and circadian genes (Cmedtim and Cmedper) showed no significant differences. After silencing Cmedcry1, the take-off proportion significantly decreased. Thus, Cmedcry1 is involved in the decrease in light intensity induced take-off behaviour in C. medinalis. CONCLUSIONS: This study can help further explain the molecular mechanisms behind insect migration, especially light perception and signal transmission during take-off phases.

Bioactivity of silverleaf nightshade (Solanum elaeagnifolium Cav.) berries parts against Galleria mellonella and Erwinia carotovora and LC-MS chemical profile of its potential extract.

Natural products received much attention as an environmentally beneficial solution for pest management. Therefore, the extracts of invasive silverleaf nightshade (Solanum elaeagnifolium Cav.) weeds using their berries parts (seeds, peels and mucilage) supported by bioassay-guided fractionation were tested against both the greater wax moth (Galleria mellonella) and Erwinia carotovora pv. carotovora causes of the blackleg of potatoes. The seeds and peels of S. elaeagnifolium were successively extracted by maceration using dichloromethane (DCM), ethyl acetate (EtOAc), and ethanol (EtOH), respectively. While, its mucilage was extracted using EtOAc. The successive EtOH extract of the plant seeds had promising inhibition efficacy and the best minimal inhibition concentration (MIC) of 50 µg/ml against E. Carotovora amongst other extracts (DCM and EtOAc of the plant berries parts). Depending on dose response activity, EtOH extract had G. mellonella larval mortality and pupal duration rates (LC50; 198.30 and LC95; 1294.73 µg/ml), respectively. Additionally, this EtOH extract of seeds was fractionated using preparative TLC to three characteristic bands. The insecticidal and bacterial activities of these isolated bands (SEA, SEB, and SEC) were evaluated at a dose of 100 µg/ml, causing mortality by 48.48, 62.63 and 92.93% (G. mellonella larvae) and inhibition by 15.22, 0.00 and 31.66 mm (E. carotovora), respectively. Moreover, the separated major three bands were tentatively identified using LC-ESI-MS analysis revealing the presence of two phenolic acids; chlorogenic acid (SEA) and dicaffeoyl quinic acid (SEB) in addition to one steroidal saponin (SEC) annotated as borassoside E or yamoscin. Finally, the plant seeds' successive EtOH extract as well as its active constituents, exhibited potential broad-spectrum activity and the ability to participate in future pest management initiatives. A field study is also recommended to validate its bio-efficacy against selected pests and to develop its formulations.

Temperatures above 37°C increase virulence of a convergent Klebsiella pneumoniae sequence type 307 strain.

Background: Convergence of Klebsiella pneumoniae (KP) pathotypes has been increasingly reported in recent years. These pathogens combine features of both multidrug-resistant and hypervirulent KP. However, clinically used indicators for hypervirulent KP identification, such as hypermucoviscosity, appear to be differentially expressed in convergent KP, potential outbreak clones are difficult to identify. We aimed to fill such knowledge gaps by investigating the temperature dependence of hypermucoviscosity and virulence in a convergent KP strain isolated during a clonal outbreak and belonging to the high-risk sequence type (ST)307. Methods: Hypermucoviscosity, biofilm formation, and mortality rates in Galleria mellonella larvae were examined at different temperatures (room temperature, 28°C, 37°C, 40°C and 42°C) and with various phenotypic experiments including electron microscopy. The underlying mechanisms of the phenotypic changes were explored via qPCR analysis to evaluate plasmid copy numbers, and transcriptomics. Results: Our results show a temperature-dependent switch above 37°C towards a hypermucoviscous phenotype, consistent with increased biofilm formation and in vivo mortality, possibly reflecting a bacterial response to fever-like conditions. Furthermore, we observed an increase in plasmid copy number for a hybrid plasmid harboring carbapenemase and rmpA genes. However, transcriptomic analysis revealed no changes in rmpA expression at higher temperatures, suggesting alternative regulatory pathways. Conclusion: This study not only elucidates the impact of elevated temperatures on hypermucoviscosity and virulence in convergent KP but also sheds light on previously unrecognized aspects of its adaptive behavior, underscoring its resilience to changing environments.

A ghost moth olfactory prototype of the lepidopteran sex communication.

Sex role differentiation is a widespread phenomenon. Sex pheromones are often associated with sex roles and convey sex-specific information. In Lepidoptera, females release sex pheromones to attract males, which evolve sophisticated olfactory structures to relay pheromone signals. However, in some primitive moths, sex role differentiation becomes diverged. Here, we introduce the chromosome-level genome assembly from ancestral Himalaya ghost moths, revealing a unique olfactory evolution pattern and sex role parity among Lepidoptera. These olfactory structures of the ghost moths are characterized by a dense population of trichoid sensilla, both larger male and female antennal entry parts of brains, compared to the evolutionary later Lepidoptera. Furthermore, a unique tandem of 34 odorant receptor 19 homologs in Thitarodes xiaojinensis (TxiaOr19) has been identified, which presents overlapped motifs with pheromone receptors (PRs). Interestingly, the expanded TxiaOr19 was predicted to have unconventional tuning patterns compared to canonical PRs, with nonsexual dimorphic olfactory neuropils discovered, which contributes to the observed equal sex roles in Thitarodes adults. Additionally, transposable element activity bursts have provided traceable loci landscapes where parallel diversifications occurred between TxiaOr19 and PRs, indicating that the Or19 homolog expansions were diversified to PRs during evolution and thus established the classic sex roles in higher moths. This study elucidates an olfactory prototype of intermediate sex communication from Himalaya ghost moths.

Response of growth and physiological enzyme activities in Eriogyna pyretorum to various host plants.

Morphological attributes and chemical composition of host plants shape growth and development of phytophagous insects via influences on their behavior and physiological processes. This research delves into the relationship between Eriogyna pyretorum and various host plants through studuying how feeding on different host tree species affect growth, development, and physiological enzyme activities. We examined E. pyretorum response to three distinct host plants: Camphora officinarum, Liquidambar formosana and Pterocarya stenoptera. Notably, larvae feeding on C. officinarum and L. formosana displayed accelerated development, increased pupal length, and higher survival rates compared to those on P. stenoptera. This underlines the pivotal role of host plant selection in shaping the E. pyretorum's life cycle. The activities of a-amylase, lipase and protective enzymes were the highest in larvae fed on the most suitable host L. formosana which indicated that the increase of these enzyme activities was closely related to growth and development. Furthermore, our investigation revealed a relationship between enzymatic activities and host plants. Digestive enzymes, protective enzymes, and detoxifying enzymes exhibited substantial variations contingent upon the ingested host plant. Moreover, the total phenolics content in the host plant leaves manifested a noteworthy positive correlation with catalase and lipase activities. In contrast, a marked negative correlation emerged with glutathione S-transferase and α-amylase activities. The total developmental duration of larvae exhibited a significant positive correlation with the activities of GST and CarE. The survival rate of larvae showed a significant positive correlation with CYP450. These observations underscore the insect's remarkable adaptability in orchestrating metabolic processes in accordance with available nutritional resources. This study highlights the interplay between E. pyretorum and its host plants, offering novel insights into how different vegetation types influence growth, development, and physiological responses. These findings contribute to a deeper comprehension of insect-plant interactions, with potential applications in pest management and ecological conservation.

Exploration-exploitation model of moth-inspired olfactory navigation.

Navigation of male moths towards females during the mating search offers a unique perspective on the exploration-exploitation (EE) model in decision-making. This study uses the EE model to explain male moth pheromone-driven flight paths. Wind tunnel measurements and three-dimensional tracking using infrared cameras have been leveraged to gain insights into male moth behaviour. During the experiments in the wind tunnel, disturbance to the airflow has been added and the effect of increased fluctuations on moth flights has been analysed, in the context of the proposed EE model. The exploration and exploitation phases are separated using a genetic algorithm to the experimentally obtained dataset of moth three-dimensional trajectories. First, the exploration-to-exploitation rate (EER) increases with distance from the source of the female pheromone is demonstrated, which can be explained in the context of the EE model. Furthermore, our findings reveal a compelling relationship between EER and increased flow fluctuations near the pheromone source. Using an olfactory navigation simulation and our moth-inspired navigation model, the phenomenon where male moths exhibit an enhanced EER as turbulence levels increase is explained. This research extends our understanding of optimal navigation strategies based on general biological EE models and supports the development of bioinspired navigation algorithms.