Structural and functional characterization of NDBP-4 family antimicrobial peptides from the scorpion Mesomexovis variegatus

Sources of Lipopeptides and Their Applications in Food and Human Health: A Review

Lipopeptides (LPs) are widely sourced surface-active natural products with a wide range of functions and low toxicity, high potency, and good biodegradability. In this paper, we summarize, for the first time, the plant, animal, microbial, and synthetic sources of LPs. We also introduce the applications of LPs in food and human health, including (1) LPs can inhibit the growth of food microorganisms during production and preservation. They can also be added to food packaging materials for preservation and freshness during transportation, and can be used as additives to improve the taste of food. (2) LPs can provide amino acids and promote protein synthesis and cellular repair. Due to their broad-spectrum antimicrobial properties, they exhibit good anticancer effects and biological activities. This review summarizes, for the first time, the sources of LPs and their applications in food and human health, laying the foundation for the development and application of LPs.

Novel Synthetic Peptide Agelaia-12 Has Improved Activity Against Mycobacterium abscessus Complex

Fast-growing mycobacteria cause difficult-to-treat infections due to their high intrinsic resistance to antibiotics as well as disinfectant agents. Mycobacterium abscessus complex (MAC) is the main cause of nontuberculous mycobacteria diseases. In this work, we evaluated the activity of the novel synthetic antimicrobial peptide, Agelaia-12, against Mycobacterium abscessus and M. massiliense. Agelaia-12 showed a minimum inhibitory concentration (MIC) of 25 μM detected against M. abscessus and M. massiliense with no cytotoxicity. The scanning electronic microscopy analysis of mycobacterial treated with Agelaia-12 demonstrated the presence of filamentous structures and aggregation of the cells. Congo red binding assay of M. abscessus exhibited altered dye accumulation after treatment with Agelaia-12. Treatment of M. abscessus- or M. massiliense-infected murine macrophages with Agelaia-12 decreased the mycobacterial load by 92% for the tested strains. Additionally, IFN-y KO mice infected with M. abscessus or M. massiliense and treated with Agelaia-12 showed a 98% reduction in lung bacterial load. Thus, the synthetic peptide Agelaia-12 may be a promising biomolecule for the treatment of mycobacteriosis, and its structural properties may serve as a foundational model for the design and development of novel pharmaceutical agents aimed at combating this disease.

A Critical Review of Short Antimicrobial Peptides from Scorpion Venoms, Their Physicochemical Attributes, and Potential for the Development of New Drugs

Scorpion venoms have proven to be excellent sources of antimicrobial agents. However, although many of them have been functionally characterized, they remain underutilized as pharmacological agents, despite their evident therapeutic potential. In this review, we discuss the physicochemical properties of short scorpion venom antimicrobial peptides (ssAMPs). Being generally short (13-25 aa) and amidated, their proven antimicrobial activity is generally explained by parameters such as their net charge, the hydrophobic moment, or the degree of helicity. However, for a complete understanding of their biological activities, also considering the properties of the target membranes is of great relevance. Here, with an extensive analysis of the physicochemical, structural, and thermodynamic parameters associated with these biomolecules, we propose a theoretical framework for the rational design of new antimicrobial drugs. Through a comparison of these physicochemical properties with the bioactivity of ssAMPs in pathogenic bacteria such as Staphylococcus aureus or Acinetobacter baumannii, it is evident that in addition to the net charge, the hydrophobic moment, electrostatic energy, or intrinsic flexibility are determining parameters to understand their performance. Although the correlation between these parameters is very complex, the consensus of our analysis suggests that there is a delicate balance between them and that modifying one affects the rest. Understanding the contribution of lipid composition to their bioactivities is also underestimated, which suggests that for each peptide, there is a physiological context to consider for the rational design of new drugs.

Scorpion venom peptides: Molecular diversity, structural characteristics, and therapeutic use from channelopathies to viral infections and cancers

Animal venom is an important evolutionary innovation in nature. As one of the most representative animal venoms, scorpion venom contains an extremely diverse set of bioactive peptides. Scorpion venom peptides not only are 'poisons' that immobilize, paralyze, kill, or dissolve preys but also become important candidates for drug development and design. Here, the review focuses on the molecular diversity of scorpion venom peptides, their typical structural characteristics, and their multiple therapeutic or pharmaceutical applications in channelopathies, viral infections and cancers. Especially, the group of scorpion toxin TRPTx targeting transient receptor potential (TRP) channels is systematically summarized and worthy of attention because TRP channels play a crucial role in the regulation of homeostasis and the occurrence of diseases in human. We also further establish the potential relationship between the molecular characteristics and functional applications of scorpion venom peptides to provide a research basis for modern drug development and clinical utilization of scorpion venom resources.

The remarkably enzyme-rich venom of the Big Bend Scorpion (Diplocentrus whitei)

Scorpion venoms have long been studied for their peptide discovery potential, with modern high-throughput venom-characterization techniques paving the way for the discovery of thousands of novel putative toxins. Research into these toxins has provided insight into the pathology and treatment of human diseases, even resulting in the development of one compound with Food and Drug Administration (FDA) approval. Although most of this research has focused on the toxins of scorpion species considered medically significant to humans, the venom of harmless scorpion species possess toxins that are homologous to those from medically significant species, indicating that harmless scorpion venoms may also serve as valuable sources of novel peptide variants. Furthermore, as harmless scorpions represent a vast majority of scorpion species diversity, and therefore venom toxin diversity, venoms from these species likely contain entirely new toxin classes. We sequenced the venom-gland transcriptome and venom proteome of two male Big Bend scorpions (Diplocentrus whitei), providing the first high-throughput venom characterization for a member of this genus. We identified a total of 82 toxins in the venom of D. whitei, 25 of which were identified in both the transcriptome and proteome, and 57 of which were only identified in the transcriptome. Furthermore, we identified a unique, enzyme-rich venom dominated by serine proteases and the first arylsulfatase B toxins identified in scorpions.

Antimicrobial Activity Developed by Scorpion Venoms and Its Peptide Component

Microbial infections represent a problem of great importance at the public health level, with a high rate of morbidity-mortality worldwide. However, treating the different diseases generated by microorganisms requires a gradual increase in acquired resistance when applying or using them against various antibiotic therapies. Resistance is caused by various molecular mechanisms of microorganisms, thus reducing their effectiveness. Consequently, there is a need to search for new opportunities through natural sources with antimicrobial activity. One alternative is using peptides present in different scorpion venoms, specifically from the Buthidae family. Different peptides with biological activity in microorganisms have been characterized as preventing their growth or inhibiting their replication. Therefore, they represent an alternative to be used in the design and development of new-generation antimicrobial drugs in different types of microorganisms, such as bacteria, fungi, viruses, and parasites. Essential aspects for its disclosure, as shown in this review, are the studies carried out on different types of peptides in scorpion venoms with activity against pathogenic microorganisms, highlighting their high therapeutic potential.

Functional characterization, antimicrobial effects, and potential antibacterial mechanisms of new mastoparan peptides from hornet venom (Vespa ducalis, Vespa mandarinia, and Vespa affinis)

Antibiotic-resistant bacteria are a major threat to global public health, and there is an urgent need to find effective, antimicrobial treatments that can be well tolerated by humans. Hornet venom is known to have antimicrobial properties, and contains peptides with similarity to known antimicrobial eptides (AMPs), mastoparans. We identified multiple new AMPs from the venom glands of Vespa ducalis (U-VVTX-Vm1a, U-VVTX-Vm1b, and U-VVTX-Vm1c), Vespa mandarinia (U-VVTX-Vm1d), and Vespa affinis (U-VVTX-Vm1e). All of these AMPs have highly similar sequences and are related to the toxic peptide, mastoparan. Our newly identified AMPs have α-helical structures, are amphiphilic, and have antimicrobial properties. Both U-VVTX-Vm1b and U-VVTX-Vm1e killed bacteria, Staphylococcus aureus ATCC25923 and Escherichia coli ATCC25922, at the concentrations of 16 μg/mL and 32 μg/mL, respectively. None of the five AMPs exhibited strong toxicity as measured via their hemolytic activity on red blood cells. U-VVTX-Vm1b was able to increase the permeability of E. coli ATCC25922 and degrade its genomic DNA. These results are promising, demonstrate the value of investigating hornet venom as an antimicrobial treatment, and add to the growing arsenal of such naturally derived treatments.