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One natural antimicrobial peptide (EpVP2a, Eumenes pomiformis Venom Peptide 2a) found in the venom of a potter wasp (Eumenes pomiformis) and six analogs were synthesized and tested to compare their antimicrobial, antifungal, pesticide, and hemolytic activity with the wild type. Our results indicated that while the original peptide and the synthetic analogs had no antifungal activity or anti-bacterial activity against Pseudomonas aeruginosa, the original peptide and the analog with substitution of the aspartic acid on the sequence by a lysine (EpVP2a-D2K2) had activity against Escherichia coli, Staphylococcus aureus and Bacillus subtilis. This same analog also shows significant insecticide activity. The analog with substitution of lysine with a slightly smaller ornithine had activity against E. coli and B. subtilis. All analogs show low hemolytic activity compared to the natural peptide. The peptide with a reverse sequence to the natural one (EpVp2a Retro) shows low helix structure which can also explain why it has no antibacterial activity and low hemolytic activity. Circular dichroism spectra show that these peptides form an alpha helix structure and their amino acid positions predict an amphipathic nature., Competing Interests: Declaration of competing interest The authors declare that they have no known competing financial interests or personal relationships that could have appeared to influence the work reported in this paper., (Copyright © 2023 Elsevier Ltd. All rights reserved.)

Solitary aculeate wasps are abundant and diverse hymenopteran insects that disable prey using venom. The venom may possess neuromodulation, immunomodulatory, metabolic-modulatory and antimicrobial functions. Venom analysis of transcriptomes and proteomes has been previously performed in social and parasitoid wasp species. We develop methodologies including mass spectrometry-based shotgun proteomics to analyse the protein constituents from venom sacs of the solitary aculeate wasp Cerceris rybyensis. The venom sac constituents of C. rybyensis are discussed with respect to other wasp species., (Copyright © 2019 Elsevier Ltd. All rights reserved.)

Vespa tropica, a social wasp locally found in Thailand is responsible for many out off the record accidental stings due to close encounters with human activities and because of the animal's highly potent venom. Phospholipase (PLA) is one of the major proteins commonly found in insect venom. In this work, V. tropica phospholipase was successfully isolated, purified and characterized. Three isoforms PLAs have been purified using reversed phase HPLC, and are named VesT1s (VesT1.01a, VesT1.01b and VesT1.02). They are not glycoproteins. VesT1.01s has a molecular weight of 33.72 kDa while for VesT1.02 a mass of 34 kDa was found. The deduced sequence of the mature VesT1.02 protein is composed of 301 amino acid residues (1005 bp), including the catalytic triad (Ser-His-Asp), which is similar to other wasp venom PLAs. The 12 cysteine residues found are conserved among venom PLA1. They form six disulfide bonds, and therefore have no free sulfhydryl groups. Based on homology modelling, VesT1.02 belongs to the α/β hydrolase fold family. Its structure is composed of 10 β-sheets and 11 α-helixes, characterized by a β-strand/εSer/α-helix structural motif, which contains the Gly-X-Ser-X-Gly consensus sequence. The shortened lid and shortened β9 loop, which play important roles in substrate selectivity, cause this enzyme to only exhibit PLA activity. Moreover, these PLAs have been shown to be highly thermally stable after heating at 100 °C for 5 min. We propose that an inserted Pro residue might be involved in this high thermo-stability., (Copyright © 2018 Elsevier Ltd. All rights reserved.)

The encyrtid parasitoid, Diversinervus elegans (Hymenoptera: Encyrtidae), is a natural enemy of the notorious scale pests belonging to the family of Coccidae. Venom containing a rich source of bioactive molecules is a key virulent factor used to regulate host physiology by parasitoids. Although knowledge regarding venom constituents accumulated from limited parasitoids has provided insights into their roles in host-parasitoid interaction, toxins involving in manipulating scale physiology remain sparsely documented. Here, a total number of 48 putative venom proteins were identified from D. elegans using an integrative transcriptomic and proteomic approach. The majority of them such as serine protease, esterase, and major royal jelly protein have been found in venom of other several parasitoid species. Several venom proteins including three novel proteins having unknown function were firstly revealed. Quantitative real time PCR analysis demonstrated that 16 venom genes displayed female-biased expression, which might be important for parasitism success. These data enrich our understanding of parasitoid venom evolution and diversity, and will undoubtedly help deciphering functional venom proteins as potential candidates for pest control., (Copyright © 2017 Elsevier Ltd. All rights reserved.)

Peptide agents are regarded as potential candidates for overcoming the life-threatening resistance of pathogenic microorganisms to classic antibiotics. Accordingly, a peptidomic and genomic investigation of natural antimicrobial peptides (AMPs) can provide structure-functional information for designing peptide antibiotics with therapeutic potential. In the present study, we identified nine AMPs from the venom gland of the wasp Vespa tropica using combined methods of peptidomics and genomics. These AMPs were classified into two different families based on sequence similarity, mastoparan and vespid chemotactic peptides (VCPs), and thus named mastoparan-VT1 to -VT7, VCP-VT1 and -VT2. Among these nine AMPs, mastoparan-VT1 and VCP-VT1 are identical to peptides from other wasps. These AMPs exerted broad-spectrum antimicrobial activity against standard and clinically isolated strains of bacteria. In addition, they showed weak hemolytic activity toward human erythrocytes. Our results reveal that identical AMPs are widely distributed in different wasp venoms and might provide templates for the development of novel peptide antibiotics., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

Hymenoptera venoms are constituted by a complex mixture of chemically or pharmacologically bioactive agents, such as phospholipases, hyaluronidases and mastoparans. Venoms can also contain substances that are able to inhibit and/or diminish the genotoxic or mutagenic action of other compounds that are capable of promoting damages in the genetic material. Thus, the present study aimed to assess the effect of the venom of Polybia paulista, a neotropical wasp, by assays with HepG2 cells maintained in culture. The cytotoxic potential of the wasp venom, assessed by the methyl thiazolyl tetrazolium assay (MTT assay), was tested for the concentrations of 10 μg/mL, 5 μg/mL and 1 μg/mL. As these concentrations were not cytotoxic, they were used to evaluate the genotoxic (comet assay) and mutagenic potential (micronucleus test) of the venom. In this study, it was verified that these concentrations induced damages in the DNA of the exposed cells, and it was necessary to test lower concentrations until it was found those that were not considered genotoxic and mutagenic. The concentrations of 1 ng/mL, 100 pg/mL and 10 pg/mL, which did not induce genotoxicity and mutagenicity, were used in four different treatments (post-treatment, pre-treatment, simultaneous treatment with and without incubation), in order to evaluate if these concentrations were able to inhibit or decrease the genotoxic and mutagenic action of methyl methanesulfonate (MMS). None of the concentrations was able to inhibit and/or decrease the MMS activity. The genotoxic and mutagenic activity of the venom of P. paulista could be caused by the action of phospholipase, mastoparan and hyaluronidase, which are able to disrupt the cell membrane and thereby interact with the genetic material of the cells or even facilitate the entrance of other compounds of the venom that can act on the DNA. Another possible explanation for the genotoxicity and mutagenicity of the venom can be the presence of substances able to trigger inflammatory process and, consequently, generate oxygen reactive species that can interact with the DNA of the exposed cells., (Copyright © 2013 Elsevier Ltd. All rights reserved.)

The Thai banded tiger wasp (Vespa affinis) is one of the most dangerous vespid species in Southeast Asia, and stinging accidents involving this species still cause fatalities. In the present study, four forms of V. affinis phospholipase A(1) were identified through a proteomics approach. Two of these enzymes were purified by reverse-phase chromatography, and their biochemical properties were characterised. These enzymes, designated Ves a 1s, are not glycoproteins and exist as 33441.5 and 33474.4 Da proteins, which corresponded with the 34-kDa band observed via SDS-PAGE. The thermal stabilities of these enzymes were stronger than snake venom. Using an in vivo assay, no difference was found in the toxicities of the different isoforms. Furthermore, the toxicity of these enzymes does not appear to be correlated with their PLA(1) activity. The cDNAs of the full-length version of Ves a 1s revealed that the Ves a 1 gene consists of a 1005-bp ORF, which encodes 334 amino acid residues, and 67- and 227-bp 5' and 3' UTRs, respectively. The two isoforms are different by three nucleotide substitutions, resulting in the replacement of two amino acids. Through sequence alignment, these enzymes were classified as members of the pancreatic lipase family. The structural modelling of Ves a 1 used the rat pancreatic lipase-related protein 2 (1bu8A) as a template because it has PLA(1) activity, which demonstrated that this enzyme belongs to the α/β hydrolase fold family. The Ves a 1 structure, which is composed of seven α-helixes and eleven β-strands, contains the β-strand/ɛSer/α-helix structural motif, which contains the Gly-X-Ser-X-Gly consensus sequence. The typical surface structures that play important roles in substrate selectivity (the lid domain and the β9 loop) were shortened in the Ves a 1 structure, which suggests that this enzyme may only exhibit phospholipase activity. Moreover, the observed insertion of proline into the lid domain of the Ves a 1 structure is rare. We therefore propose that this proline residue might be involved in the stability and activity of Ves a 1s., (Copyright © 2012 Elsevier Ltd. All rights reserved.)

The venom of social wasps has been poorly studied so far, despite the high number of accidents in humans and assessment of the use of these wasps as a biological control of pests. The study of the pharmacological effects of the venom is of great importance since the poisoning is dangerous causing serious systemic effects, including death in the case of multiple attacks. In this study, the pharmacological activities of venom from the social wasp Synoeca cyanea were evaluated by the following assays: LD50 in mice, the behavioural effects and the hemorrhagic activity induced by the venom in mice, the oedematogenic activity in rat, the haemolysis in human blood, the stimulating effect on guinea-pig smooth muscle, and the antimicrobial activity. The aim was to determine the toxic effects of venom and to perform a comparative study with earlier work conducted with venom from other wasp species. Results showed that S. cyanea venom produced a potent dose-dependent oedema, as well as antibacterial and haemolytic activities, suggesting the presence of histamine, serotonin, kinins and other molecules related to increased vascular permeability and cytolytic activity in this venom. Despite previous studies with wasp venoms, S. cyanea venom presented a slight hemorrhagic effect. Data obtained in the smooth muscle assay also suggest the presence of BK or analogues in S. cyanea whole venom. The knowledge of symptoms and effects produced by S. cyanea venom is critical for health organizations, in order to improve clinical treatment in accidents caused by wasp stings., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Four novel peptides were isolated from the venoms of the solitary eumenine wasps Eumenes rubrofemoratus and Eumenes fraterculus. Their sequences were determined by MALDI-TOF/TOF (matrix assisted laser desorption/ionization time-of-flight mass spectrometry) analysis, Edman degradation and solid-phase synthesis. Two of them, eumenitin-R (LNLKGLIKKVASLLN) and eumenitin-F (LNLKGLFKKVASLLT), are highly homologous to eumenitin, an antimicrobial peptide from a solitary eumenine wasp, whereas the other two, EMP-ER (FDIMGLIKKVAGAL-NH(2)) and EMP-EF (FDVMGIIKKIAGAL-NH(2)), are similar to eumenine mastoparan-AF (EMP-AF), a mast cell degranulating peptide from a solitary eumenine wasp. These sequences have the characteristic features of linear cationic cytolytic peptides; rich in hydrophobic and basic amino acids with no disulfide bond, and accordingly, they can be predicted to adopt an amphipathic α-helix secondary structure. In fact, the CD (circular dichroism) spectra of these peptides showed significant α-helical conformation content in the presence of TFE (trifluoroethanol), SDS (sodium dodecylsulfate) and asolectin vesicles. In the biological evaluation, all the peptides exhibited a significant broad-spectrum antimicrobial activity, and moderate mast cell degranulation and leishmanicidal activities, but showed virtually no hemolytic activity., (Copyright © 2011 Elsevier Ltd. All rights reserved.)

Secretory proteins were identified in the venoms of two solitary hunting wasps, Eumenes pomiformis and Orancistrocerus drewseni, by SDS-PAGE in conjunction with mass analysis. More than 30 protein bands (2-300 kDa) were detected from the crude venom of each wasp. With the aid of the previously constructed venom gland/sac-specific EST libraries, a total of 31 and 20 proteins were identified from 18 to 20 distinctive protein bands of E. pomiformis and O. drewseni venoms, respectively. Arginine kinase was the most predominant protein in both wasp venoms. Along with the full-length arginine kinase, a truncated form, which was known to have paralytic activity on a spider, was a common predominant protein in the two wasp venoms. Insulin/insulin-like peptide-binding protein was abundantly found only in E. pomiformis venom, which might be due to its unique behaviors of oviposition and provision. The presence of various immune response-related proteins and antioxidants suggested that wasps might use their venom to maintain prey fresh while feeding wasp larvae by protecting the prey from microbial invasion and physiological stresses. It seemed that some venom proteins are secreted into venom fluid from venom gland cells via exosomes, not by signal sequence-mediated transport processes., (Copyright 2010 Elsevier Ltd. All rights reserved.)

The venom volatiles of five paper wasp species, four European belonging to the subgenus Polistes sensu stricto (P. dominulus, P. gallicus, P. nimphus, P. sulcifer) and one belonging to the Asian subgenus Gyrostoma (P. olivaceus), have been sampled by headspace solid phase micro-extraction and analysed by gas chromatography-mass spectrometry. The venom volatile components of Polistes wasps have never been fully investigated before, although the presence of some spiroacetals has been previously reported in literature. The composition of the venom was qualitatively and quantitatively different among the analysed species with the major substances tentatively identified, on the basis of their mass spectra, as: spiroacetals, mainly 2,8-dimethyl-1,7-dioxaspiro[5.5]undecane, two amides, N-(3-methylbutyl)acetamide and N-(3-methylbutyl)propanamide and acetates of saturated, mono- and di-unsaturated 2-alcohols with an odd number of carbon atoms in the chain. The acetate of a di-unsaturated 2-alcohol, present in two isomeric forms, identified as (E)- and (Z)-5-tangerinol has never been reported in literature for insects. Propanoates of the same 2-alcohols were only found in the venom of P. gallicus. Both the amides and the above-mentioned spiroacetal have been already shown to be alarm pheromones in other social wasps, while the acetates and propanoates have ever been reported in this taxon.

The hornet possesses highly toxic venom, which is rich in toxin, enzymes and biologically active peptides. Many bioactive substances were identified from wasp venom. Two families of antimicrobial peptides were purified and characterized from the venom of the wasp, Vespamagnifica (Smith). The primary structures of these peptides are homologous to those of chemotactic peptides and mastoparans isolated from other vespid venoms. They also share similarity to temporins which are amphibian antimicrobial peptides identified from the skin of the frog, Ranaboylii. These peptides show antimicrobial activities against bacteria and fungi. However, they show little hemolytic activity against human blood red cells.

Crude venoms from two parasitoid species, Pteromalus puparum and Nasonia vitripennis (Hymenoptera: Pteromalidae) were assayed for biological activities toward hemocytes from two species of their natural hosts and eight species of their non-natural hosts as well as two lines of cultured Lepidoptera cells, respectively. By inhibiting the spreading and viability of insect hemocytes, the venom from P. puparum displayed significantly higher activities toward plasmatocytes and granular cells from both larvae and pupae of two natural hosts, Pieris rapae and Papilio xuthus, and lower activity toward those from Spodoptera litura, Musca domestica and Sarcophaga peregrina. However, no effect was found towards any type of hemocytes from other five insects tested, namely, Ectropis oblique, Galleria mellonella, Sesamia inferens, Bombyx mori and Parnara guttata. In contrast, the venom from N. vitripennis showed a narrower range of targeted insects. It appeared to have highly adverse effects on the spreading and viability of plasmatocytes and granular cells only from the natural hosts, M. domestica and S. peregrina, little toxicity to cells from P. rapae and P. xuthus, and no effect on any of the other insects tested. Pteromalus puparum venom also apparently presented a high ability to block the spreading of Tn-5B1-4 cells derived from Trichoplusia ni, and high cytotoxicity to the cells and Ha cells derived from Helicoverpa armigera. Nasonia vitripennis venom, however, only had a marked lethal effect to Ha cells. In addition, the possibility that the host range of a defined parasitoid could be assessed using our method of treating hemocytes from candidate insects with venom in vitro, and the potential of our venoms tested in the development of bio-insecticides, insect-resistant transgenic plants, are discussed.

The venom of the neotropical social wasp Agelaia pallipes pallipes was fractionated by RP-HPLC resulting in the elution of seven fractions; the last two were re-fractionated under RP-HPLC by using isocratic elution conditions and the purity of the fractions were confirmed by using ESI-MS analysis. Both fractions are constituted of peptide components, which were sequenced by Edman degradation chemistry, resulting in the following sequences: Protonectin I-L-G-T-I-L-G-L-L-K-G-L-NH(2). Agelaia-MP I-N-W-L-K-L-G-K-A-I-I-D-A-L-NH(2). Both peptides are manually synthesized on solid-phase and functionally characterized by using Wistar rats cells. Protonectin is a non-hemolytic chemotactic peptide for polymorphonucleated leukocytes (PMNL), presenting some mast cell degranulating activity and potent antimicrobial action both against Gram-positive and Gram-negative bacteria. Agelaia-MP was characterized as a hemolytic mast cell degranulator toxin, presenting a poor antimicrobial action and no chemotaxis for PMNL.

We describe a simple method for obtaining good a quantity of pure venom from a small parasitoid wasp, Melittobia digitata. Crushing the insect's head causes venom to be extruded from the ovipositor that dries rapidly as it is collected onto an insect pin. This technique may be applicable to other parasitic Hymenoptera.

A review is presented of our ongoing research projects on the protein components of the saliva of human body lice and of the non-paralyzing venom of wasps in the subfamily Cheloninae. Sodium dodecyl sulfate-polyacryamide gel electrophoretic analysis of lice salivary gland proteins showed a predominance of high and intermediate mol. wt proteins. Immunoblotting with a low titer polyclonal antiserum to lice salivary proteins indicated that some, but not all, of the predominant high mol. wt salivary gland proteins are injected into the host during feeding. The venom of a Chelonus sp. wasp contains a chitinase, and a 33,000 mol. wt protein with a primary structure composed mostly of a series of 12 tandem repeats of a 14-residue sequence. The N-terminus of this protein and its homologs in a related species of Ascogaster share a conserved adjacent pair of acidic residues. Epitope mapping/immunoprecipitation experiments now in progress will provide information on which linear motifs are on the surface of the protein, and will thereby provide information on the tertiary structure of the protein.