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Abstract Peptide toxins found in sea anemones venom have diverse properties that make them important research subjects in the fields of pharmacology, neuroscience and biotechnology. This study used high-throughput sequencing technology to systematically analyze the venom components of the tentacles, column, and mesenterial filaments of sea anemone Heteractis crispa, revealing the diversity and complexity of sea anemone toxins in different tissues. A total of 1049 transcripts were identified and categorized into 60 families, of which 91.0% were proteins and 9.0% were peptides. Of those 1049 transcripts, 416, 291, and 307 putative proteins and peptide precursors were identified from tentacles, column, and mesenterial filaments respectively, while 428 were identified when the datasets were combined. Of these putative toxin sequences, 42 were detected in all three tissues, including 33 proteins and 9 peptides, with the majority of peptides being ShKT domain, β-defensin, and Kunitz-type. In addition, this study applied bioinformatics approaches to predict the family classification, 3D structures, and functional annotation of these representative peptides, as well as the evolutionary relationships between peptides, laying the foundation for the next step of peptide pharmacological activity research.

AbstractContext Our previous studies have found that total flavonoid of Alpinia officinarum Hance (Zingiberaceae) (F.AOH) had protective effects on gastric ulcer (GU).Objective To investigate the protective mechanism of F.AOH on acetic acid-induced chronic GUs in rats and ethanol-induced GES-1 cells damage.Materials and methods In vivo: Gastric damage was induced in SD rats by administering acetic acid after oral treatment with F-AOH at 54, 27 and 13.5 mg/kg (2 weeks of continuous gavage). After a comprehensive evaluation of rats’ serum and gastric tissue-related indicators, gene transcriptome sequencing, qPCR and Western blotting were used to investigate the mechanism further. In vivo: GES-1 cells were incubated with F-AOH (8, 4 and 2 μg/mL) for 16 h and treated with 7% ethanol for 4 h. Transwell and flow cytometry were employed to detect migration and apoptosis of cells.Results F.AOH effectively reduced the area of GUs in rats (from 11.2 ± 1.89 to 2.19 ± 0.95), reversing ethanol-induced cells apoptosis (from 23 ± 1.3 to 8.11 ± 0.93%). It also inhibited the expression of endothelin-1 (ET-1) and iNOS proteins, decreasing the levels of TNF-α IL-6 in serum, improving oxidative stress levels and increasing the expression of Bcl-2/Bax dimer genes. In addition, 4005 differentially expressed genes between the acetic acid model and the drug groups. Through experimental verification, F.AOH can inhibit the activation of TLR4/NF-κB signalling pathway and TRPV1 receptor.Conclusions F.AOH, as an effective gastric protective plant component, had potential therapeutic value in anti-inflammatory pain and antioxidative stress gastrointestinal diseases.

The escalating resistance of agricultural pests to chemical insecticides necessitates the development of novel, efficient, and safe biological insecticides. Conus quercinus, a vermivorous cone snail, yields a crude venom rich in peptides for marine worm predation. This study screened six α-conotoxins with insecticidal potential from a previously constructed transcriptome database of C. quercinus, characterized by two disulfide bonds. These conotoxins were derived via solid-phase peptide synthesis (SPPS) and folded using two-step iodine oxidation for further insecticidal activity validation, such as CCK-8 assay and insect bioassay. The final results confirmed the insecticidal activities of the six α-conotoxins, with Qc1.15 and Qc1.18 exhibiting high insecticidal activity. In addition, structural analysis via homology modeling and functional insights from molecular docking offer a preliminary look into their potential insecticidal mechanisms. In summary, this study provides essential references and foundations for developing novel insecticides.

Sea anemone venom, abundant in protein and peptide toxins, serves primarily for predatory defense and competition. This study delves into the insulin-like peptides (ILPs) present in sea anemones, particularly focusing on their role in potentially inducing hypoglycemic shock in prey. We identified five distinct ILPs in Exaiptasia diaphana, exhibiting varied sequences. Among these, ILP-Ap04 was successfully synthesized using solid phase peptide synthesis (SPPS) to evaluate its hypoglycemic activity. When tested in zebrafish, ILP-Ap04 significantly reduced blood glucose levels in a model of diabetes induced by streptozotocin (STZ) and glucose, concurrently affecting the normal locomotor behavior of zebrafish larvae. Furthermore, molecular docking studies revealed ILP-Ap04’s unique interaction with the human insulin receptor, characterized by a detailed hydrogen-bonding network, which supports a unique mechanism for its hypoglycemic effects. Our findings suggest that sea anemones have evolved sophisticated strategies to activate insulin receptors in vertebrates, providing innovative insights into the design of novel drugs for the treatment of diabetes.

IntroductionAlpinia oxyphylla Miquel (A. oxyphylla), one of the “Four Famous South Medicines” in China, is an essential understory cash crop that is planted widely in the Hainan, Guangdong, Guangxi, and Fujian provinces. Particularly, A. oxyphylla from Hainan province is highly valued as the best national product for geo-herbalism and is an important indicator of traditional Chinese medicine efficacy. However, the molecular mechanism underlying the formation of its quality remains unspecified.MethodsTo this end, we employed a multi-omics approach to investigate the authentic quality formation of A. oxyphylla.ResultsIn this study, we present a high-quality chromosome-level genome assembly of A. oxyphylla, with contig N50 of 76.96 Mb and a size of approximately 2.08Gb. A total of 38,178 genes were annotated, and the long terminal repeats were found to have a high frequency of 61.70%. Phylogenetic analysis demonstrated a recent whole-genome duplication event (WGD), which occurred before A. oxyphylla’s divergence from W. villosa (~14 Mya) and is shared by other species from the Zingiberaceae family (Ks, ~0.3; 4DTv, ~0.125). Further, 17 regions from four provinces were comprehensively assessed for their metabolite content, and the quality of these four regions varied significantly. Finally, genomic, metabolic, and transcriptomic analyses undertaken on these regions revealed that the content of nootkatone in Hainan was significantly different from that in other provinces.DiscussionOverall, our findings provide novel insights into germplasm conservation, geo-herbalism evaluation, and functional genomic research for the medicinal plant A. oxyphylla.

The venoms of various sea anemones are rich in diverse toxins, which usually play a dual role in capturing prey and deterring predators. However, the complex components of such venoms have not been well known yet. Here, venomics of integrating transcriptomic and proteomic technologies was applied for the first time to identify putative protein and peptide toxins from different tissues of the representative sea anemone, Heteractis magnifica. The transcriptomic analysis of H. magnifica identified 728 putative toxin sequences, including 442 and 381 from the tentacles and the column, respectively, and they were assigned to 68 gene superfamilies. The proteomic analysis confirmed 101 protein and peptide toxins in the venom, including 91 in the tentacles and 39 in the column. The integrated venomics also confirmed that some toxins such as the ShK-like peptides and defensins are co-expressed in both the tentacles and the column. Meanwhile, a homology analysis was conducted to predict the three-dimensional structures and potential activity of seven representative toxins. Altogether, this venomics study revealed the venom complexity of H. magnifica, which will help deepen our understanding of cnidarian toxins, thereby supporting the in-depth development of valuable marine drugs.

Cone snails possess a diverse array of novel peptide toxins, which selectively target ion channels and receptors in the nervous and cardiovascular systems. These numerous novel peptide toxins are a valuable resource for future marine drug development. In this review, we compared and analyzed the sequence diversity, three-dimensional structural variations, and evolutionary aspects of venom insulin derived from different cone snail species. The comparative analysis reveals that there are significant variations in the sequences and three-dimensional structures of venom insulins from cone snails with different feeding habits. Notably, the venom insulin of some piscivorous cone snails exhibits a greater similarity to humans and zebrafish insulins. It is important to emphasize that these venom insulins play a crucial role in the predatory strategies of these cone snails. Furthermore, a phylogenetic tree was constructed to trace the lineage of venom insulin sequences, shedding light on the evolutionary interconnections among cone snails with diverse diets.

As primitive metazoa, sea anemones are rich in various bioactive peptide neurotoxins. These peptides have been applied to neuroscience research tools or directly developed as marine drugs. To date, more than 1100 species of sea anemones have been reported, but only 5% of the species have been used to isolate and identify sea anemone peptide neurotoxins. There is an urgent need for more systematic discovery and study of peptide neurotoxins in sea anemones. In this review, we have gathered the currently available methods from crude venom purification and gene cloning to venom multiomics, employing these techniques for discovering novel sea anemone peptide neurotoxins. In addition, the three-dimensional structures and targets of sea anemone peptide neurotoxins are summarized. Therefore, the purpose of this review is to provide a reference for the discovery, development, and utilization of sea anemone peptide neurotoxins.

Individual cone snail (Conus sp.) contains thousands of bioactive peptides, but there are limited studies on its antimicrobial peptides (AMPs). Here, we investigated AMPs along with AMP-derived genes in the representative Chinese tubular cone snail (C. betulinus) by integration of our previously published multi-omics (genomics, transcriptomics, and peptidomics) data. We identified a total of 466 putative AMP-derived genes from the genome, and most of them were annotated as histones. While at the mRNA level, only 77 AMP-derived genes were confirmed with transcriptomic evidence, among them Ubiquicidin, cgUbiquitin, Ap, and VK10 were the most abundant transcripts in the venom gland. In addition, 30 AMPs were further validated by peptidomics data. After in silico analysis including 3D modeling, 11 putative AMPs were chemically synthesized for an in vitro assessment, and eight peptides were proved with good antifungal activity. In summary, this work systematically characterized the AMP repertoire in C. betulinus. This valuable genetic resource provides a solid foundation for in-depth therapeutic applications and drug development.

Marine cone snail venoms represent a vast library of bioactive peptides with proven potential as research tools, drug leads, and therapeutics. In this study, a transcriptome library of four different organs, namely radular sheath, venom duct, venom gland, and salivary gland, from piscivorous Conus striatus was constructed and sequenced using both Illumina next-generation sequencing (NGS) and PacBio third-generation sequencing (TGS) technologies. A total of 428 conotoxin precursor peptides were retrieved from these transcriptome data, of which 413 conotoxin sequences assigned to 13 gene superfamilies, and 15 conotoxin sequences were classified as unassigned families. It is worth noting that there were significant differences in the diversity of conotoxins identified from the NGS and TGS data: 82 conotoxins were identified from the NGS datasets while 366 conotoxins from the TGS datasets. Interestingly, we found point mutations in the signal peptide sequences of some conotoxins with the same mature sequence. Therefore, TGS broke the traditional view of the conservation of conotoxin signal peptides and the variability of mature peptides obtained by NGS technology. These results shed light on the integrated NGS and TGS technologies to mine diverse conotoxins in Conus species, which will greatly contribute to the discovery of novel conotoxins and the development of new marine drugs.

Objective(s): Experimental studies have revealed that Alpinia officinarum Hance (Zingiberaceae) exhibits a gastrointestinal protective effect. The present study aimed to investigate the effects of diphenylheptanes (DPHs) extracted from A. officinarum rhizomes on ethanol-induced gastric ulcers in BALB/c mice.Materials and Methods: A total of 60 female BALB/c mice were divided into six groups as follows: negative control, which received sodium carboxymethyl cellulose; positive control, which received ethanol; treatment control, which received ethanol+ranitidine; ethanol+high dose of DPHs; ethanol+medium dose of DPHs; ethanol+low dose of DPHs. Different doses of DPHs were administered orally once daily for seven consecutive days before the animals were subjected to ethanol-induced gastric ulcers.Results: Various doses of DPHs significantly reduced Gastric ulcers index when compared with the positive control. DPHs treatments and treatment control increased the activity of superoxide dismutase; decreased the levels of inflammatory mediators, malondialdehyde, motilin, and gastrin; decreased the activity of inducible nitric oxide synthase and cyclooxygenase-2; and inhibited the expression of Toll-like receptor 4, myeloid differentiation factor 88, and nuclear factor-κB at the protein and mRNA levels. In addition, DPHs inhibited the expression of transient receptor potential vanilloid 1, calcitonin gene-related peptide, and increased the expression of substance P at the protein and mRNA levels. Conclusion: The protective effect of DPHs extracted from A. officinarum rhizomes against ethanol-induced gastric damages in mice suggests that the extract can be used as an auxiliary supplement for the prevention and treatment of gastric ulcers.

Abstract Although there are various Conus species with publicly available transcriptome and proteome data, no genome assembly has been reported yet. Here, using Chinese tubular cone snail (C. betulinus) as a representative, we sequenced and assembled the first Conus genome with original identification of 133 genome-widely distributed conopeptide genes. After integration of our genomics, transcriptomics, and peptidomics data in the same species, we established a primary genetic central dogma of diverse conopeptides, assuming a rough number ratio of ~1:1:1:10s for the total genes: transcripts: proteins: post-translationally modified peptides. This ratio may be special for this worm-hunting Conus species, due to the high diversity of various Conus genomes and the big number ranges of conopeptide genes, transcripts, and peptides in previous reports of diverse Conus species. Only a fraction (45.9%) of the identified conotopeptide genes from our achieved genome assembly are transcribed with transcriptomic evidence, and few genes individually correspond to multiple transcripts possibly due to intraspecies or mutation-based variances. Variable peptide processing at the proteomic level, generating a big diversity of venom conopeptides with alternative cleavage sites, post-translational modifications, and N-/C-terminal truncations, may explain how the 133 genes and ~123 transcripts can generate thousands of conopeptides in the venom of individual C. betulinus. We also predicted many conopeptides with high stereostructural similarities to the putative analgesic ω-MVIIA, addiction therapy AuIB and insecticide ImI, suggesting that our current genome assembly for C. betulinus is a valuable genetic resource for high-throughput prediction and development of potential pharmaceuticals.

Sea anemone venom is a marine drug resource library with pharmacological and biotechnology value, and it contains complex and diverse functional peptide neurotoxins. However, the venom components of only a limited number of sea anemone species have been globally evaluated by transcriptomics and proteomics. In this study, 533 putative protein as well as peptide toxin sequences were found on a large scale from dissimilar developmental stages of sea anemone Exaiptasia diaphana, which can be divided into 75 known superfamilies according to the predicted functions. Among them, the proportion of protein is 72.98%, and its main families are metalloproteases, chymotrypsinogen like, collagen, pancreatic lipase-associated protein like, and G-protein coupled receptor, while the proportion of peptides is 27.02%, and main families are ShK domain, thrombin, Kunitz-type, defensin, as well as insulin-like peptide. Finally, typical anemone peptide neurotoxins were screened, and the 3D structure and pharmacological activity of these anemone peptide neurotoxins were predicted by homology modeling. We elucidate on a valuable high-throughput approach for obtaining sea anemone proteins and peptides. Our findings form the basis for targeted studies on the diversity as well as pharmacological effects of sea anemone peptide neurotoxins.

The complete mitochondrial genome of the tubular cone snail Conus betulinus is presented in this study. The C. betulinus mitochondrial genome was 16,240 bp with 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, 2 ribosomal RNA (rRNA) genes, and a non-coding AT-rich region (D-loop). The overall base composition was estimated to be 25.67% for A, 38.26% for T, 21.38% for G, and 14.69% for C, with a high A + T content of 63.93%. Phylogenetic analyses based on 13 PCGs showed the close relationship of vermivorous C. betulinus with the common ancestor of molluscivorous Conus textile and Conus gloriamaris, providing a basis for further studies on the phylogenetics of cone snails according to their dietary type.

Cone snail venoms have been considered a valuable treasure for international scientists and businessmen, mainly due to their pharmacological applications in development of marine drugs for treatment of various human diseases. To date, around 800 Conus species are recorded, and each of them produces over 1,000 venom peptides (termed as conopeptides or conotoxins). This reflects the high diversity and complexity of cone snails, although most of their venoms are still uncharacterized. Advanced multiomics (such as genomics, transcriptomics, and proteomics) approaches have been recently developed to mine diverse Conus venom samples, with the main aim to predict and identify potentially interesting conopeptides in an efficient way. Some bioinformatics techniques have been applied to predict and design novel conopeptide sequences, related targets, and their binding modes. This review provides an overview of current knowledge on the high diversity of conopeptides and multiomics advances in high-throughput prediction of novel conopeptide sequences, as well as molecular modeling and design of potential drugs based on the predicted or validated interactions between these toxins and their molecular targets.

Alpinia oxyphylla Miq. (A. oxyphylla) is an important edible and traditional herbal medicine. In this study, the complete chloroplast genome of A. oxyphylla was sequenced, analysed, and compared to five species in the Zingiberaceae family. The size of the A. oxyphylla chloroplast genome was 161351 bp, which consisted of a large single-copy (LSC, 87248 bp) and small single-copy (SSC, 16175 bp) region separated by a pair of inverted repeats (IRa and IRb, 28964 bp each). The genome encoded 132 unique genes, including 87 protein-coding genes, 37 tRNAs and four rRNAs. The GC content of the genome was 36.17%. A total of 53 simple sequence repeats (SSRs) and 80 long repeats were identified in the A. oxyphylla chloroplast genome. The chloroplast genome of A. oxyphylla shared the highest sequence similarity of >90% with the chloroplast genome of A. zerumbet, and six chloroplast genomes in the Zingiberaceae family were compared by using CGView Comparison Tool (CCT). According to the phylogenetic tree, the Zingiberaceae family is divided into two categories, which coincide with the classification of the characteristics of sun-like and shade-like in plants. Our results reveal the phototrophic component of NADH-dehydrogenase (ndhB and ndhC), photosystem II (psbZ) and ATP synthase (atpE, atpF) exhibit adaptive evolution under different environments, and the strength of light is an important trigger for the adaptations at the chloroplast level.

Complete mitochondrial genome (mitogenome) sequence of a worm-hunting cone snail, Conus quercinus, was reported in this study. Its mitogenome, the longest one (16,460 bp) among reported Conus specie, is composed of 13 protein-coding genes (PCGs), 22 transfer RNA (tRNA) genes, two ribosomal RNA (rRNA) genes and one D-loop region. The mitochondrial gene arrangement is highly-conserved and identical to other reported. However, the D-loop region of C. quercinus is the longest (943 bp) with the higher A+T content (71.3%) and a long AT tandem repeat stretch (68 bp). Subsequent phylogenetic analysis demonstrated that three different dietary types (vermivorous, molluscivorous and piscivorous) of cone snails are clustered separately, suggesting that the phylogenetics of cone snails is related to their dietary types. In conclusion, our current work improves our understanding of the mitogenomic structure and evolutionary status of the vermivorous C. quercinus, which support the putative hypothesis that the Conus ancestor was vermivorous.

The primary objective of this study was to realize the large-scale discovery of conotoxin sequences from different organs (including the venom duct, venom bulb and salivary gland) of the vermivorous Oak cone snail, Conus quercinus. Using high-throughput transcriptome sequencing, we identified 133 putative conotoxins that belong to 34 known superfamilies, of which nine were previously reported while the remaining 124 were novel conotoxins, with 17 in new and unassigned conotoxin groups. A-, O1-, M-, and I2- superfamilies were the most abundant, and the cysteine frameworks XIII and VIII were observed for the first time in the A- and I2-superfamilies. The transcriptome data from the venom duct, venom bulb and salivary gland showed considerable inter-organizational variations. Each organ had many exclusive conotoxins, and only seven of all the inferred mature peptides were common in the three organs. As expected, most of the identified conotoxins were synthesized in the venom duct at relatively high levels; however, a number of conotoxins were also identified in the venom bulb and the salivary gland with very low transcription levels. Therefore, various organs have different conotoxins with high diversity, suggesting greater contributions from several organs to the high-throughput discovery of new conotoxins for future drug development.

Marine drugs have developed rapidly in recent decades. Cone snails, a group of more than 700 species, have always been one of the focuses for new drug discovery. These venomous snails capture prey using a diverse array of unique bioactive neurotoxins, usually named as conotoxins or conopeptides. These conotoxins have proven to be valuable pharmacological probes and potential drugs due to their high specificity and affinity to ion channels, receptors, and transporters in the nervous systems of target prey and humans. Several research groups, including ours, have examined the venom gland of cone snails using a combination of transcriptomic and proteomic sequencing, and revealed the existence of hundreds of conotoxin transcripts and thousands of conopeptides in each Conus species. Over 2000 nucleotide and 8000 peptide sequences of conotoxins have been published, and the number is still increasing quickly. However, more than 98% of these sequences still lack 3D structural and functional information. With the rapid development of genomics and bioinformatics in recent years, functional predictions and investigations on conotoxins are making great progress in promoting the discovery of novel drugs. For example, ω-MVIIA was approved by the U.S. Food and Drug Administration in 2004 to treat chronic pain, and nine more conotoxins are at various stages of preclinical or clinical evaluation. In short, the genus Conus, the big family of cone snails, has become an important genetic resource for conotoxin identification and drug development.

Conotoxins in the venom of cone snails (Conus spp.) are a mixture of active peptides that work as blockers, agonists, antagonists, or inactivators of various ion channels. Recently we reported a high-throughput method to identify 215 conotoxin transcripts from the Chinese tubular cone snail, C. betulinus. Here, based on the previous datasets of four transcriptomes from three venom ducts and one venom bulb, we explored ion channel-based conotoxins and predicted their related ion channel receptors. Homologous analysis was also performed for the most abundant ion channel protein, voltage-gated potassium (Kv; with Kv1.1 as the representative), and the most studied ion channel receptor, nicotinic acetylcholine receptor (nAChR; with α2-nAChR as the representative), in different animals. Our transcriptomic survey demonstrated that ion channel-based conotoxins and related ion channel proteins/receptors transcribe differentially between the venom duct and the venom bulb. In addition, we observed that putative κ-conotoxins were the most common conotoxins with the highest transcription levels in the examined C. betulinus. Furthermore, Kv1.1 and α2-nAChR were conserved in their functional domains of deduced protein sequences, suggesting similar effects of conotoxins via the ion channels in various species, including human beings. In a word, our present work suggests a high-throughput way to develop conotoxins as potential drugs for treatment of ion channel-associated human diseases.

Most previous studies have focused on analgesic and anti-cancer activities for the conotoxins identified from piscivorous and molluscivorous cone snails, but little attention has been devoted to insecticidal activity of conotoxins from the dominant vermivorous species. As a representative vermivorous cone snail, the Chinese tubular cone snail (Conus betulinus) is the dominant Conus species inhabiting the South China Sea. We sequenced related venom transcriptomes from C. betulinus using both the next-generation sequencing and traditional Sanger sequencing technologies, and a comprehensive library of 215 conotoxin transcripts was constructed. In our current study, six conotoxins with potential insecticidal activity were screened out from our conotoxin library by homologous search with a reported positive control (alpha-conotoxin ImI from C. imperialis) as the query. Subsequently, these conotoxins were synthesized by chemical solid-phase and oxidative folding for further insecticidal activity validation, such as MTT assay, insect bioassay and homology modeling. The final results proved insecticidal activities of our achieved six conotoxins from the transcriptome-based dataset. Interestingly, two of them presented a lot of high insecticidal activity, which supports their usefulness for a trial as insecticides in field investigations. In summary, our present work provides a good example for high throughput development of biological insecticides on basis of the accumulated genomic resources.

The voltage-gated sodium channel (Nav) is widely present in mammals and can generate cell action potentials, which are related to many diseases. The μ-Conotoxins (μ-CTx) isolated from the venom of cone snails can specifically block the voltage-gated sodium channel ; it can be widely used as a necessary probe to distinguish the Nav channel subtypes. In this study, the effects of eight μ-CTx on different Nav channel isoforms were reviewed, and sequence alignment and protein homologous modeling were used to predict their biological activities, and the structure-activity relationship between μ-CTx and mutagenesis strategies. [ABSTRACT FROM AUTHOR]

[Objectives] Peptides was extracted from Haemadipsa hainana and its activity was studied. [Methods] Electric stimulation, water extraction and ul-trasonic extraction were used to extract the peptides from H hainana. Then the protein content and molecular weight distribution of H haipana peptides were de-tected by the BCA method and SDS-PAGE method, respectively. The antithrombin activity and analgesic activity of the three peptide extracts of H haipana were detected by Markwardt thrombin titration method and mouse hot plate experiment, respectively. [Results] There extraction methods of electric stimulation, water extraction and ultrasonic extraction were used to extract the peptide extract of H haiiana, and the yields were as foUows: water extraction > electrical stimulation > ultrasonic extraction. The three peptide extracts from H hainana had antithrombin activity, and the antithrombin activity was as foUows: water extraction > ultrasonic extraction > electrical stimulation. Through the hot plate experiment in mice, it was verified that the three peptide extracts of H haiiana had analgesic activity, and the analgesic activity was water extraction > electric stimulation > ultrasonic extraction. The analgesic activity of high-dose (100 mg/kg) group of H hainana obtained by water extraction was slightly weaker than that of tramadol. [ Conclusions] This study confirmed that the peptide extract of H haiiana had certain antithrombin and analgesic activity, laying a foundation for the subsequent development and application of H haiiana. [ABSTRACT FROM AUTHOR]

[Objectives] This study was conducted to investigate the chemical synthesis of peptide K-CTx-btgf)2. [Methods]Linear peptide-CTx-btgO2 was synthesized by solid phase peptide synthesis (SPPS). After oxidation and folding of the linear peptide, mass spectrometry identification and high performance liquid chromatography (HPLC) purification were performed. Then, the MTT method and insect injection method were applied to study its insecticidal activity. [Results] The peptide K-CTx-btgO2 was successfully synthesized by the SPPS method, and identified for the formation of disulfide bonds by mass spectrometry identification, and the purity after HPLC separation was greater than 95%. The MTT experiment showed that the peptide K-CTx-btgO2 could inhibit the growth of insect cells sf9, with a half effective dose of 0.13 nM. The insect injection experiment showed that the peptide-CTx-btgf)2 could effectively kill Tenebrio molitor, with a half lethal dose of 15.6 nM. The results of the electrophysiological experiment showed that 10 jjlM peptide K-CTx-btgO2 had no blocking activity on murine acetylcholine α2β3 and α3β4. Therefore, the peptide tc-CTx-btgO2 had a good inhibitory effect on the growth of insect cells, highly effective insecticidal activity and weak mammalian toxicity. [Conclusions]This study lays a foundation for the development of new, safe and efficient peptide biological insecticides. [ABSTRACT FROM AUTHOR]

[Objectives] This study was conducted to synthesize sea anemone peptide Ap-GI and investigate its insecticidal activity. [Methods] The linear peptide Ap-GI was synthesized by solid phase peptide synthesis(SPPS), and the linear peptide was subjected to the two-step oxidative folding, mass spectrometry identification and high performance liquid chromatography(HPLC) purification. Then, the MTT method and insect injection method were used to study its insecticidal activity. [Results] The synthesized sea anemone peptide had a purity of 95%. The test results of the MTT method showed that the peptide Ap-GI had the activity of inhibiting the growth of insect cells sf9 with the median effective dose of 0.7 nM; and the test results of the injection method on yellow mealworms showed that the peptide Ap-GI had high insecticidal activity, and the median lethal dose was 16.9 nM. [Conclusions] The sea anemone peptide Ap-GI from Aiptasia pallida has a good inhibitory effect on the growth of insect cells and high-efficiency insecticidal activity, which can lay a foundation for the development of new, safe and efficient peptide biological insecticides. [ABSTRACT FROM AUTHOR]