Insecticidal Activity of Doxycycline against the Common Bedbug.
Ontology highlight
ABSTRACT:
SUBMITTER: Pietri JE
PROVIDER: S-EPMC7179621 | biostudies-literature | 2020 Apr
REPOSITORIES: biostudies-literature
Publications
Insecticidal Activity of Doxycycline against the Common Bedbug.
Pietri Jose E JE Liang Dangsheng D
Antimicrobial agents and chemotherapy 20200421 5
There is an ongoing need for safe and effective anti-bedbug compounds. Here, we tested the toxicity of three antimicrobial agents against bedbugs when administered orally. We reveal that doxycycline has direct insecticidal activity at 250 μg/ml (0.025%) that is particularly strong against immature bedbugs and appears to be independent of antimicrobial activity. Future studies to determine the mechanisms behind this property could be useful for the development of orally active insecticides or ant ...[more]
Similar Datasets
Project description:Bacillus thuringiensis is the most successful microbial insecticide agent and its proteins have been studied for many years due to its toxicity against insects mainly belonging to the orders Lepidoptera, Diptera and Coleoptera, which are pests of agro-forestry and medical-veterinary interest. However, studies on the interactions between this bacterium and the insect species classified in the order Coleoptera are more limited when compared to other insect orders. To date, 45 Cry proteins, 2 Cyt proteins, 11 Vip proteins, and 2 Sip proteins have been reported with activity against coleopteran species. A number of these proteins have been successfully used in some insecticidal formulations and in the construction of transgenic crops to provide protection against main beetle pests. In this review, we provide an update on the activity of Bt toxins against coleopteran insects, as well as specific information about the structure and mode of action of coleopteran Bt proteins.
| S-EPMC7404982 | biostudies-literature
Project description:Food availability in the environment is often low and variable, constraining organisms in their resource allocation to different life-history traits. For example, variation in food availability is likely to induce condition-dependent investment in reproduction. Further, diet has been shown to affect ejaculate size, composition and quality. How these effects translate into male reproductive success or change male mating behavior is still largely unknown. Here, we concentrated on the effect of meal size on ejaculate production, male reproductive success and mating behavior in the common bedbug Cimex lectularius. We analyzed the production of sperm and seminal fluid within three different feeding regimes in six different populations. Males receiving large meals produced significantly more sperm and seminal fluid than males receiving small meals or no meals at all. While such condition-dependent ejaculate production did not affect the number of offspring produced after a single mating, food-restricted males could perform significantly fewer matings than fully fed males. Therefore, in a multiple mating context food-restricted males paid a fitness cost and might have to adjust their mating strategy according to the ejaculate available to them. Our results indicate that meal size has no direct effect on ejaculate quality, but food availability forces a condition-dependent mating rate on males. Environmental variation translating into variation in male reproductive traits reveals that natural selection can interact with sexual selection and shape reproductive traits. As males can modulate their ejaculate size depending on the mating situation, future studies are needed to elucidate whether environmental variation affecting the amount of ejaculate available might induce different mating strategies.
| S-EPMC4797159 | biostudies-literature
Project description:Vegetative insecticidal proteins 3A (Vip3A) were important insecticidal proteins for control of lepidopteran pests. Previous study demonstrated that Vip3Aa and Vip3Ad showed significant difference in insecticidal activities against Spodoptera exigua, while the molecular mechanism remained ambiguous. Here we demonstrated that the difference in insecticidal activities between Vip3Aa and Vip3Ad might be caused by the difference in stability of Vip3Aa and Vip3Ad in S. exigua midgut protease. Vip3Aa was quite stable while Vip3Ad could be further degraded. Molecular dynamics simulation revealed that Vip3Aa was more stable than Vip3Ad, with smaller RMSD and RMSF value. Amino acid sequence alignment indicated that three were three extra prolines (P591, P605 and P779) located on Vip3Aa. We further identified that residue P591 played a crucial role on stability and insecticidal activity of Vip3Aa. Taken together, our study demonstrated that the stability was essential for the insecticidal activity of Vip3A toxins, which might provide new insight into the action mode of Vip3A toxins and contribute to the design Vip3A variants with improved stability and insecticidal activity.
| S-EPMC9283630 | biostudies-literature
Project description:Whitefly infestation of cotton crop imparts enormous damage to cotton yield by severely affecting plant health, vigour and transmitting Cotton Leaf Curl Virus (CLCuV). Genetic modification of cotton helps to overcome both the direct whitefly infestation as well as CLCuV based cotton yield losses. We have constitutively overexpressed asparaginase (ZmASN) gene in Gossypium hirsutum to overcome the cotton yield losses imparted by whitefly infestation. We achieved 2.54% transformation efficiency in CIM-482 by Agrobacterium-mediated shoot apex transformation method. The relative qRT-PCR revealed 40-fold higher transcripts of asparaginase in transgenic cotton line vs. non-transgenic cotton lines. Metabolic analysis showed higher contents of aspartic acid and glutamic acid in seeds and phloem sap of the transgenic cotton lines. Phenotypically, the transgenic cotton lines showed vigorous growth and height, greater number of bolls, and yield. Among six representative transgenic cotton lines, line 14 had higher photosynthetic rate, stomatal conductance, smooth fiber surface, increased fiber convolutions (SEM analysis) and 95% whitefly mortality as compared to non-transgenic cotton line. The gene integration analysis by fluorescence in situ hybridization showed single copy gene integration at chromosome number 1. Collectively, asparaginase gene demonstrated potential to control whitefly infestation, post-infestation damages and improve cotton plant health and yield: a pre-requisite for farmer's community.
| S-EPMC7265412 | biostudies-literature
Project description:The spotted wing drosophila (SWD), Drosophila suzukii Matsumura (Diptera: Drosophilidae), is an invasive polyphagous pest of soft-skinned fruit that has started to threaten small fruit production in Europe since 2008. High reproductive capacity, short generation time, and difficulties in visualizing early damage contribute to its rapid spread. Currently, the control strategy against D. suzukii mostly relies on treatment with synthetic insecticides. Keeping in mind that this pest causes the greatest damage during the harvesting period, control using chemicals is not recommended due to the increased risk of high pesticide residue levels in the fruit. With the aim of reducing the use of insecticides, there is a need for developing an environmentally safer way of control. Alternative solutions could rely on the use of essential oils (EOs), which can be used in conventional and organic production systems. Four essential oils, geranium (Pelargonium graveolens), dill (Anethum graveolens), Scots pine (Pinus sylvestris), and bergamot (Citrus bergamia), were assessed for their insecticidal effects using four different tests (contact toxicity, fumigant-contact toxicity, repellent effect, and multiple-choice tests). The EOs applied were dissolved in acetone at three different concentrations. The most promising one was the geranium essential oil, which had the best effect in all conducted tests, even at the lowest applied concentration. Geranium oil caused very high mortality (95%), even at the lowest concentration applied, after 24 h in the fumigant-contact test, and it caused a mortality of over 85% in the contact test. It was also noticed that geranium demonstrated a deterrent effect by repelling females from laying eggs for four days after at the lowest applied concentration. Scots pine and dill EOs have moderate to strong effects in most tests. The mortality of 100% was achieved for the highest applied concentration in the fumigant-contact and contact tests. Bergamot EO did not have any significant insecticidal activity. Geranium, Scots pine, and dill have great potential to be used as an environmentally friendly way of controlling D. suzukii as they exhibit deterrent, repellent, and insecticidal effects.
| S-EPMC10647715 | biostudies-literature
Project description:The diamondback moth, Plutella xylostella, is one of the most important pests of cruciferous crops. We have earlier shown that N6-(2-hydroxyethyl)-adenosine (HEA) exhibits insecticidal activity against P. xylostella. In the present study we investigated the possible mechanism of insecticidal action of HEA on P. xylostella. HEA is a derivative of adenosine, therefore, we speculated whether it acts via P. xylostella adenosine receptor (PxAdoR). We used RNAi approach to silence PxAdoR gene and used antagonist of denosine receptor (AdoR) to study the insecticidal effect of HEA. We cloned the whole sequence of PxAdoR gene. A BLAST search using NCBI protein database showed a 61% identity with the Drosophila adenosine receptor (DmAdoR) and a 32-35% identity with human AdoR. Though the amino acids sequence of PxAdoR was different compared to other adenosine receptors, most of the amino acids that are known to be important for adenosine receptor ligand binding and signaling were present. However, only 30% binding sites key residues was similar between PxAdoR and A1R. HEA, at a dose of 1 mg/mL, was found to be lethal to the second-instar larvae of P. xylostella, and a significant reduction of mortality and growth inhibition ratio were obtained when HEA was administered to the larvae along with PxAdoR-dsRNA or antagonist of AdoR (SCH58261) for 36, 48, or 60 h. Especially at 48 h, the rate of growth inhibition of the PxAdoR knockdown group was 3.5-fold less than that of the HEA group, and the corrected mortality of SCH58261 group was reduced almost 2-fold compared with the HEA group. Our findings show that HEA may exert its insecticidal activity against P. xylostella larvae via acting on PxAdoR.
| S-EPMC5036850 | biostudies-literature
Project description:A novel Bacillus thuringiensis crystal protein with a silent activity against the Colorado potato beetle is described. The crystal proteins are produced as bipyramidal crystals. These crystals contain a protein of 129 kDa with a trypsin-resistant core fragment of 72 kDa. Neither a spore-crystal mixture nor in vitro-solubilized crystals are toxic to any of several Lepidoptera and Coleoptera species tested. In contrast, a trypsin-treated solution containing the 72-kDa tryptic core fragment of the protoxin is highly toxic to Colorado potato beetle larvae. The crystal protein-encoding gene was cloned and sequenced. The inferred amino acid sequence of the putative toxic fragment has 37, 32, and 33% homology to the CryIIIA, CryIIIB, and CryIIID toxins, respectively. Interestingly, the 501 C-terminal amino acids show 41 to 48% amino acid identity with corresponding C-terminal amino acid sequences of other crystal proteins. Because of the toxicity of the fragment to the Colorado potato beetle and because of the distinct similarities of the toxic fragment with the other CryIII proteins, this gene was given a new subclass name (cryIIIC) within the CryIII class of coleopteran-active crystal proteins. CryIIIC represents the first example of a crystal protein with a silent activity towards coleopteran insect larvae. Natural CryIIIC crystals are not toxic. Toxicity is revealed only after an in vitro solubilization and activation step.
| S-EPMC195818 | biostudies-other
Project description:Many bacteria live on host surfaces, in cells and in specific organ systems. In comparison with gut microbiomes, the bacterial communities of reproductive organs (genital microbiomes) have received little attention. During mating, male and female genitalia interact and copulatory wounds occur, providing an entrance for sexually transmitted microbes. Besides being potentially harmful to the host, invading microbes might interact with resident genital microbes and affect immunity. Apart from the investigation of sexually transmitted symbionts, few studies have addressed how mating changes genital microbiomes. We dissected reproductive organs from virgin and mated common bedbugs, Cimex lectularius L., and sequenced their microbiomes to investigate composition and mating-induced changes. We show that mating changes the genital microbiomes, suggesting bacteria are sexually transmitted. Also, genital microbiomes varied between populations and the sexes. This provides evidence for local and sex-specific adaptation of bacteria and hosts, suggesting bacteria might play an important role in shaping the evolution of reproductive traits. Coadaptation of genital microbiomes and reproductive traits might further lead to reproductive isolation between populations, giving reproductive ecology an important role in speciation. Future studies should investigate the transmission dynamics between the sexes and populations to uncover potential reproductive barriers.
| S-EPMC7282915 | biostudies-literature
Project description:Interaction between insect herbivores and host plants can be modulated by endogenous and exogenous compounds present in the source of food and might be successfully exploited in Colorado potato beetle (CPB) pest management. Feeding tests with CPB larvae reared on three solanaceous plants (potato, eggplant and tomato) resulted in variable larval growth rates and differential susceptibility to Bacillus thuringiensis Cry3Aa toxin as a function of the host plant. An inverse correlation with toxicity was observed in Cry3Aa proteolytic patterns generated by CPB midgut brush-border membrane vesicles (BBMV) from Solanaceae-fed larvae, being the toxin most extensively proteolyzed on potato, followed by eggplant and tomato. We found that CPB cysteine proteases intestains may interact with Cry3Aa toxin and, in CPB BBMV from larvae fed all three Solanaceae, the toxin was able to compete for the hydrolysis of a papain substrate. In response to treatment with the JA-dependent plant inducer Hexanoic acid (Hx), we showed that eggplant reduced OPDA basal levels and both, potato and eggplant induced JA-Ile. CPB larvae feeding on Hx-induced plants exhibited enhanced Cry3Aa toxicity, which correlated with altered papain activity. Results indicated host-mediated effects on B. thuringiensis efficacy against CPB that can be enhanced in combination with Hx plant induction.
| S-EPMC3709778 | biostudies-literature
Project description:Many plants show significant biological activity against pests due to their unique chemical constituents. It is important to identify effective constituents for their development and utilization as botanical pesticides. Our previous study showed that Artemisia lavandulaefolia essential oil had biological activity against Plutella xylostella. Here, we isolated and identified the constituents of essential oil from A. lavandulaefolia by silica gel column chromatography. The main constituents identified were eucalyptol and caryophyllene oxide, and they were confirmed by gas chromatography-mass spectrometry (GC-MS). Eucalyptol and caryophyllene oxide showed strong contact toxicity against P. xylostella larvae after 24 h of application (Median lethal dose, LD50 = 76.97 μL/mL and 20.71 mg/mL. Furthermore, the two active constituents against P. xylostella adults showed significant fumigant activity (Mmedian lethal concentration, LC50 = 3.25 μL/L and 1.06 mg/L, respectively. Finally, we measured the detoxification enzymes and acetylcholinesterase of the larvae treated with active constituents. The eucalyptol-treated larvae displayed enhanced carboxylesterase (CarE) and glutathione-S-transferase (GST) activities in an in vivo experiment, but it was lower for acetylcholinesterase (AchE) activity. The activities of the CarE and GST significantly decreased when exposed to caryophyllene oxide. In general, the two active constituents, eucalyptol and caryophyllene oxide, showed high insecticidal activity, which demonstrates their potential to be used as natural insecticides.
| S-EPMC8707372 | biostudies-literature