A Novel Chimeric Anti-HCV Peptide Derived from Camel Lactoferrin and Molecular Level Insight on Its Interaction with E2

The emerging role of Fusobacteria in carcinogenesis

The Fusobacterium genus comprises Gram-negative, obligate anaerobic bacteria that typically reside in the periodontium of the oral cavity, gastrointestinal tract, and female genital tract. The association of Fusobacterial spp. with colorectal tumours is widely accepted, with further evidence that this pathogen may also be implicated in the development of other malignancies. Fusobacterial spp. influence malignant cell behaviours and the tumour microenvironment in various ways, which can be related to the multiple surface adhesins expressed. These adhesins include Fap2 (fibroblast-activated protein 2), CpbF (CEACAM binding protein of Fusobacteria), FadA (Fusobacterium adhesin A) and FomA (Fusobacterial outer membrane protein A). This review outlines the influence of Fusobacteria in promoting cancer initiation and progression, impacts of therapeutic outcomes and discusses potential therapeutic interventions where appropriate.

Recombinant Antimicrobial Peptides (rAMPs); Potential Applications in Medicine and Veterinary Medicine: A Review

Antibiotic resistance has become a major public health concern worldwide. Treatment of humans and animals is becoming increasingly challenging due to antibiotic resistance. Antibiotic-resistant bacteria can be transmitted from animals to humans by several routes, including direct contact, contaminated food or water, or environmental exposure. Various factors contribute to the rising problem, such as the widespread and indiscriminate exploitation of antimicrobials in both human and animal healthcare, over-prescription, misuse of antibiotics, the role of agriculture in spreading antibiotic resistance, and poor animal husbandry practices. According to the preliminary findings, recombinant antimicrobial peptides are an interesting novel area of biotechnology and medical innovation that might be employed as a secure and effective substitute for antibiotics. In this review study, we briefly examine the factors contributing to the rise of antibiotic resistance. We then introduce and discuss recombinant antimicrobial peptides as a promising strategy to address this growing problem.

A Review on cLF36, a Novel Recombinant Antimicrobial Peptide-Derived Camel Lactoferrin

Lactoferrin is an antimicrobial peptide (AMP) playing a pivotal role in numerous biological processes. The primary antimicrobial efficacy of lactoferrin is associated with its N-terminal end, which contains various peptides, such as lactoferricin and lactoferrampin. In this context, our research team has developed a refined chimeric 42-mer peptide known as cLF36 over the past few years. This peptide encompasses the complete amino acid sequence of camel lactoferrampin and partial amino acid sequence of lactoferricin. The peptide's activity against human, avian, and plant bacterial pathogens has been assessed using different biological platforms, including prokaryotic (P170 and pET) and eukaryotic (HEK293) expression systems. The peptide positively influenced the growth performance and intestinal morphology of chickens challenged with pathogen bacteria. Computational methods and in vitro studies showed the peptide's antiviral effects against hepatitis C virus, influenza virus, and rotavirus. The chimeric peptide exhibited higher activity against certain tumor cell lines compared to normal cells, which may be attributed to the peptide's interaction with negatively charged glycosaminoglycans on the surface of tumor cells. Importantly, this peptide exhibited no toxicity against host cells and demonstrated remarkable thermal and protease stability in serum. In conclusion, while our investigations suggest that the chimeric peptide, cLF36, may offer potential as a candidate or complementary option to some available antibiotics, antiviral agents, and chemical pesticides, significant uncertainties remain regarding its cost-effectiveness, as well as its pharmacodynamic and pharmacokinetic characteristics, which require further elucidation.

Optimized Antimicrobial Peptide Jelleine-I Derivative Br-J-I Inhibits Fusobacterium Nucleatum to Suppress Colorectal Cancer Progression

Colorectal cancer (CRC) is a major health burden worldwide due to its high morbidity, mortality, and complex etiology. Fusobacterium nucleatum (Fn), a Gram-negative anaerobe found in 30% of CRC patients, promotes CRC carcinogenesis, metastasis, and chemoresistance. Effective antimicrobial treatment is an unmet need for the rising CRC burden. Antimicrobial peptides (AMPs) represent a new class of antimicrobial drugs. In our previous study, we did the structure-activity study of Jelleine-I (J-I) and identified several halogenated J-I derivatives Cl-J-I, Br-J-I, and I-J-I. To determine whether those J-I derivatives can be a new therapy for bacterial-associated CRC, here we tested the antibacterial activities of these AMPs against Fn and their effects on CRC development. We found that Br-J-I showed the highest anti-Fn activity and Br-J-I may target membrane-associated FadA for Fn membrane disruption. More importantly, Fn promoted the growth of CRC cells-derived xenograft tumors. Br-J-I suppressed Fn load, colon inflammation, and Fn-induced CRC growth. Of note, Br-J-I induced better anti-CRC effects than common antibiotic metronidazole and Br-J-I sensitized the cancer-killing effect of chemotherapy drug 5-fluorouracil. These results suggest that Br-J-I could be considered as an adjunctive agent for CRC treatment and AMPs-based combination treatment is a new strategy for CRC in the future.

Molecular modeling of lactoferrin for food and nutraceutical applications: insights from in silico techniques

Lactoferrin is a protein, primarily found in milk that has attracted the interest of the food industries due to its health properties. Nevertheless, the instability of lactoferrin has limited its commercial application. Recent studies have focused on encapsulation to enhance the stability of lactoferrin. However, the molecular insights underlying the changes of structural properties of lactoferrin and the interaction with protectants remain poorly understood. Computational approaches have proven useful in understanding the structural properties of molecules and the key binding with other constituents. In this review, comprehensive information on the structure and function of lactoferrin and the binding with various molecules for food purposes are reviewed, with a special emphasis on the use of molecular dynamics simulations. The results demonstrate the application of modeling and simulations to determine key residues of lactoferrin responsible for its stability and interactions with other biomolecular components under various conditions, which are also associated with its functional benefits. These have also been extended into the potential creation of enhanced lactoferrin for commercial purposes. This review provides valuable strategies in designing novel nutraceuticals for food science practitioners and those who have interests in acquiring familiarity with the application of computational modeling for food and health purposes.

Effects of Antimicrobial Peptide Microcin C7 on Growth Performance, Immune and Intestinal Barrier Functions, and Cecal Microbiota of Broilers

Microcin C7 is an antimicrobial peptide produced by Escherichia coli, composed of a heptapeptide with a modified adenosine monophosphate. This study was performed to evaluate the effects of Microcin C7 as a potential substrate to traditional antibiotics on growth performance, immune functions, intestinal barrier, and cecal microbiota of broilers. In the current study, 300 healthy Arbor Acres broiler chicks were randomly assigned to one of five treatments including a corn-soybean basal diet and basal diet supplemented with antibiotic or 2, 4, and 6 mg/kg Microcin C7. Results showed that Microcin C7 significantly decreased the F/G ratio of broilers; significantly increased the levels of serum cytokine IL-10, immunoglobulins IgG and IgM, and ileal sIgA secretion; significantly decreased the level of serum cytokine TNF-α. Microcin C7 significantly increased villus height and V/C ratio and significantly decreased crypt depth in small intestine of broilers. Microcin C7 significantly increased gene expression of tight junction protein Occludin and ZO-1 and significantly decreased gene expression of pro-inflammatory and chemokine TNF-α, IL-8, IFN-γ, Toll-like receptors TLR2 and TLR4, and downstream molecular MyD88 in the jejunum of broilers. Microcin C7 significantly increased the number of Lactobacillus and decreased the number of total bacteria and Escherichia coli in the cecum of broilers. Microcin C7 also significantly increased short-chain fatty acid (SCFA) and lactic acid levels in the ileum and cecum of broilers. In conclusion, diet supplemented with Microcin C7 significantly improved growth performance, strengthened immune functions, enhanced intestinal barrier, and regulated cecal microbiota of broilers. Therefore, the antimicrobial peptide Microcin C7 may have the potential to be an ideal alternative to antibiotic.

Antimicrobial peptides and other peptide-like therapeutics as promising candidates to combat SARS-CoV-2

Introduction: There are currently no specific drugs and universal vaccines for Coronavirus disease 2019 (COVID-19), hence urgent effective measures are needed to discover and develop therapeutic agents. Applying peptide therapeutics and their related compounds is a promising strategy to achieve this goal. This review is written based on the literature search using several databases, previous studies, scientific reports, our current knowledge about the antimicrobial peptides (AMPs), and our personal analyses on the potential of the antiviral peptides for the treatment of COVID-19.

Areas covered: In this review, we begin with a brief description of SARS-CoV2 followed by a comprehensive description of antiviral peptides (AVPs) including natural and synthetic AMPs or AVPs and peptidomimetics. Subsequently, the structural features, mechanisms of action, limitations, and therapeutic applications of these peptides are explained.

Expert opinion: Regarding the lack and the limitations of drugs against COVID-19, AMPs, AVPs, and other peptide-like compounds such as peptidomimetics have captured the attention of researchers due to their potential antiviral activities. Some of these compounds comprise unique properties and have demonstrated the potential to fight SARS-CoV2, particularly melittin, lactoferrin, enfuvirtide, and rupintrivir that have the potential to enter animal and clinical trials for the treatment of COVID-19.

Generation of an engineered food-grade Lactococcus lactis strain for production of an antimicrobial peptide: in vitro and in silico evaluation

BACKGROUND

Foodborne pathogens and their biofilms are considered as one of the most serious problems in human health and food industry. Moreover, safety of foods is a main global concern because of the increasing use of chemical food additives. Ensuring food safety enhances interest in discovery of new alternative compounds such as antimicrobial peptides (AMPs), which can be used as bio-preservatives in the food industry. In this study, the most important antimicrobial peptides of camel milk lactoferrin (lactoferrampin and lactoferricin) were recombinantly expressed in the form of chimeric peptide (cLFchimera) in a food-grade L. lactis strain. P170 expression system was used to express secreted cLFchimera using pAMJ1653 expression vector which harbors a safe (non-antibiotic) selectable marker.

RESULTS

Peptide purification was carried out using Ni-NTA agarose column from culture medium with concentration of 0.13 mg/mL. The results of disk diffusion test revealed that cLFchimera had considerable antimicrobial activity against a number of major foodborne bacteria. Furthermore, this chimeric peptide showed strong and weak inhibitory effect on biofilm formation against P. aeruginosa, S. aureus E. faecalis, and E. coli, respectively. Antioxidant activity and thermal stability of the chimeric peptide was determined. The results showed that cLFchimera had antioxidant activity (IC50: 310 μ/mL) and its activity was not affected after 40 min of boiling. Finally, we evaluated the interaction of the peptide with LPS and DNA in bacteria using molecular dynamic simulation as two main intra and extra cellular targets for AMPs, respectively. Our in silico analysis showed that cLFchimera had strong affinity to both of these targets by positive charged residues after 50 ns molecular dynamic simulation.

CONCLUSIONS

Overall, the engineered food-grade L. lactis generated in the present study successfully expressed a secreted chimeric peptide with antimicrobial properties and could be considered as a promising bio-preservative in the food industry.