Cecropin

Antimicrobial peptides are potential alternatives to traditional antibiotics in the face of increasing bacterial resistance. Insects possess many antimicrobial peptides and have become a valuable source of novel and highly effective antimicrobial peptides. Hermetia illucens as a resource insect, for example, has the highest number of antimicrobial peptides of any dipteran. However, most antimicrobial peptides, especially cecropin, have not been comprehensively identified and have not been evaluated for their antimicrobial ability...

The prevalence of multidrug-resistant highly virulent Klebsiella pneumoniae (MDR-hvKP) requires the development of new therapeutic agents. Herein, a novel lytic phage vB_KpnS_ZX4 against MDR-hvKP was discovered in hospital sewage. Phage vB_KpnS_ZX4 had a short latent period (5 min) and a large burst size (230 PFU/cell). It can rapidly reduce the number of bacteria in vitro and improve survival rates of bacteremic mice in vivo from 0 to 80% with a single injection of 108 PFU. LysZX4, an endolysin derived from vB_KpnS_ZX4, exhibits potent antimicrobial activity in vitro in combination with ethylenediaminetetraacetic acid (EDTA)...

Mounting evidence indicates that the gut microbiota influences the neurodevelopment and behavior of insects through the gut-brain axis. However, it is currently unclear whether the gut microbiota affect the head profiles and immune pathway in pests. Here, we find that gut bacteria is essential for the immune and neural development of adult Spodoptera frugiperda, which is an extremely destructive agricultural pest worldwide. 16 S rRNA sequencing analysis showed that antibiotics exposure significantly disturbed the composition and diversity of gut bacteria...

Antimicrobial peptides are key components of the immune system. These peptides affect the membrane in various ways; some form nano-sized pores, while others only produce minor defects. Since these peptides are increasingly important in developing antimicrobial drugs, understanding the mechanism of their interactions with lipid bilayers is critical. Here, using atomic force microscopy (AFM), we investigated the effect of a synthetic hybrid peptide, CM15, on the membrane surface comprising E. coli polar lipid extract...

Egypt has witnessed the emergence of multidrug-resistant (MDR) Klebsiella pneumoniae, which has posed a serious healthcare challenge. The proper treatment choice for MDR-KP infections is not well determined which renders the problem more complicated, thus making the control of such infections a serious challenge for healthcare professionals. This study aims to encapsulate the cationic antimicrobial peptide; Cecropin-B (Cec-B), to increase its lifetime, drug targeting, and efficacy and study the antimicrobial effect of free and encapsulated recombinant rCec-B peptide on multidrug-resistant K...

Aedes aegypti is a vector of various disease-causing arboviruses. Chemical insecticide-based methods for mosquito control have increased resistance in different parts of the world. Thus, alternative control agents such as the entomopathogenic fungi are excellent candidates to control mosquitoes as part of an ecofriendly strategy. There is evidence of the potential of entomopathogenic fungal conidia and blastospores for biological control of eggs, larval and adult stages, as well as the pathogenicity of fungal microsclerotia against adults and eggs...

Antibiotic resistance is a significant and growing threat to global public health. However, antimicrobial peptides (AMPs) have shown promise as they exhibit a broad spectrum of antibacterial activities with low potential for resistance development. Insects, which inhabit a wide range of environments and are incredibly diverse, remain largely unexplored as a source of novel AMPs. To address this, we conducted a screening of the representative transcriptomes from the 1000 Insect Transcriptome Evolution (1KITE) dataset, focusing on the homologous reference genes of Cecropins, the first identified AMPs in insects known for its high efficiency...

As effector molecules of the innate immune system, antimicrobial peptides (AMPs) have gathered substantial interest as a potential future generation of antibiotics. Here, we demonstrate the anti- Pseudomonas activity and lipopolysaccharide (LPS)-binding ability of HC1 and HC10, two cecropin peptides from the black soldier fly ( Hermetia Illucens ). Both peptides are active against a wide range of Pseudomonas aeruginosa strains, including drug-resistant clinical isolates. Moreover, HC1 and HC10 can bind to lipid A, the toxic center of LPS and reduce the LPS-induced nitric oxide and cytokine production in murine macrophage cells...

[This corrects the article DOI: 10.3389/fmicb.2022.821936.].

The growing challenge of chronic wounds and antibiotic resistance has spotlighted the potential of dual-function peptides (antimicrobial and wound healing) as novel therapeutic strategies. The investigation aimed to characterize and correlate in silico the physicochemical attributes of these peptides with their biological activity. We sourced a dataset of 207 such peptides from various peptide databases, followed by a detailed analysis of their physicochemical properties using bioinformatic tools. Utilizing statistical tools like clustering, correlation, and principal component analysis (PCA), patterns and relationships were discerned among these properties...

Antimicrobial Peptides (AMPs) are key constituents of the invertebrate innate immune system and provide critical protection against microbial threat. Nematodes display diverse life strategies where they are exposed to heterogenous, microbe rich, environments highlighting their need for an innate immune system. Within the Ecdysozoa, arthropod AMPs have been well characterised, however nematode-derived AMP knowledge is limited. In this study the distribution and abundance of putative AMP-encoding genes was examined in 134 nematode genomes providing the most comprehensive profile of AMP candidates within phylum Nematoda...

The cabbage looper Trichoplusia ni is an important agricultural pest worldwide and is frequently used as a model organism for assessing entomopathogenic fungi virulence, though few studies have measured the host response repertoire to fungal biocontrol agents. Here, we quantified the immune response of T. ni larvae following exposure to two entomopathogenic fungal species: Beauveria bassiana and Cordyceps javanica . Results from our study demonstrate that T. ni larvae exposed to fungal entomopathogens had higher total phenoloxidase activity compared to controls, indicating that the melanization cascade is one of the main immune components driving defense against fungal infection and contrasting observations from other insect-fungi interaction studies...

Pseudomonas aeruginosa is an opportunistic Gram-negative bacterium responsible for severe nosocomial infections and is considered a critical pulmonary pathogen for both immunocompromised and cystic fibrosis patients. Planktonic cells of P. aeruginosa possess intrinsic and acquired resistances, inactivating several classes of conventional antibiotics. Additionally, this bacterium can grow, forming biofilms, and complex structures, further hampering the action of multiple antibiotics. Here, we report the biological properties of D-Q53 CecB, an all-D enantiomer of the silkworm natural peptide Q53 CecB...

Mosquitoes are prolific vectors of human pathogens; a clear and accurate understanding of the organization of their antimicrobial defenses is crucial for informing the development of transmission control strategies. The canonical infection response in insects, as described in the insect model Drosophila melanogaster , is pathogen type-dependent, with distinct stereotypical responses to Gram-negative bacteria and Gram-positive bacteria/fungi mediated by the activation of the Imd and Toll pathways, respectively...

The opportunistic yeast Candida albicans is the most common cause of candidiasis. With only four classes of antifungal drugs on the market, resistance is becoming a problem in the treatment of fungal infections, especially in immunocompromised patients. The development of novel antifungal drugs with different modes of action is urgent. In 2016, we developed a groundbreaking new medium-throughput method to distinguish the effects of antibacterial agents. Using small-angle X-ray scattering for biological samples (BioSAXS), it is now possible to screen hundreds of new antibacterial compounds and select those with the highest probability for a novel mode of action...

Insect herbivores frequently encounter plant defense molecules, but the physiological and ecological consequences for their immune systems are not fully understood. The majority of studies attempting to relate levels of plant defensive chemistry to herbivore immune responses have used natural population or species-level variation in plant defensive chemistry. Yet, this potentially confounds the effects of plant defense chemistry with other potential plant trait differences that may affect the expression of herbivore immunity...

Cancer is a multifaceted health issue that affects people globally and it is considered one of the leading causes of death with a high percentage of victims worldwide. In recent years, research studies have uncovered great advances in cancer diagnosis and treatment. But, there are still major drawbacks of the conventional therapies used including severe side effects, toxicity, and drug resistance. That is why it is critical to develop new drugs with advantages like low cytotoxicity and no treatment resistance to the cancer cells...

This study investigates the synergistic effect of ultrasonication and antimicrobial action of antimicrobial peptide cecropin P1 on the inactivation of Escherichia coli O157:H7 in a cylindrical ultrasonication system. The inactivation of E. coli at pH 7.4 was performed using: ultrasonication (14, 22, and 47 kHz), cecropin P1 (20 µg/mL), and a combination of both. We found the treatment at 22 kHz, 8W for 15 min of exposure and a combination of ultrasound at higher frequency (47 kHz, 8 W) and cecropin P1 for one minute of exposure were more efficient, reducing the cell density by six orders of magnitude, compared to individual treatments (ultrasound or cecropin P1 only)...

The spread of colistin-resistant bacteria is a serious threat to public health. As an alternative to traditional antibiotics, antimicrobial peptides (AMPs) show promise against multidrug resistance. In this study, we investigated the activity of the insect AMP Tricoplusia ni cecropin A ( T. ni cecropin) against colistin-resistant bacteria. T. ni cecropin exhibited significant antibacterial and antibiofilm activities against colistin-resistant Escherichia coli (ColREC) with low cytotoxicity against mammalian cells in vitro...

The extensive use of antibiotics in animal production has led to the development of antibiotic-resistant microorganisms and the search for alternative antimicrobial agents in animal production. One such compound may be antimicrobial peptides (AMPs), which are characterized by, among others, a wide range of biocidal activity. According to scientific data, insects produce the largest number of antimicrobial peptides, and the changing EU legislation has allowed processed animal protein derived from insects to be used in feed for farm animals, which, in addition to a protein supplement, may prove to be an alternative to antibiotics and antibiotic growth promoters due to their documented beneficial impact on livestock health...