Search for Articles:
Title / Keyword
Author / Affiliation / Email
Journal
Article Type
 
 
Advanced Search
 
Section
Special Issue
Volume
Issue
Number
Page
 
6.4
4.5
Journals
Microorganisms
Special Issues
Antimicrobial Peptides: Therapeutic Potentials 2.0
share announcement

Antimicrobial Peptides: Therapeutic Potentials 2.0

A special issue of Microorganisms (ISSN 2076-2607). This special issue belongs to the section "Antimicrobial Agents and Resistance".

Deadline for manuscript submissions: 20 July 2024 | Viewed by 5080

Special Issue Editor

Dr. Kai Hilpert

E-Mail Website
Guest Editor
Institute of Infection and Immunology, St George’s, University of London, London SW17 0RE, UK
Interests: antimicrobial peptides; anticancer peptides; wound healing peptides; diagnostics of mycobacteria; neuro-immunology
Special Issues, Collections and Topics in MDPI journals

Special Issue Information

Dear Colleagues,

The WHO has classified antimicrobial resistance as one of the biggest threats to global health, food security, and development today (http://www.who.int/mediacentre/factsheets/antibiotic-resistance/en/). A recent study investigated 23 pathogens and 88 pathogen–drug combinations in 204 countries and found that about 4.95 million deaths are associated with antimicrobial resistance bacterial infections (doi.org/10.1016/S0140-6736(21)02724-0). In the O’Neil Report, it is estimated that by 2050 these numbers will increase to 10,000,000, more people than currently killed by cancer. It is estimated that the additional healthcare cost for this impact will reach US$100 trillion. The situation might even intensify since the number of newly-developed antibiotics is steadily declining. FDA approval of new antimicrobials dropped to three new molecular entities (NME) in this decade. One reason for this is that most major pharmaceutical companies have stalled their research efforts for new antimicrobial compounds. In 1985 more than 30 companies undertook active anti-bacterial programs, whereas in 2013 it was less than 10.

Antimicrobial peptides (AMPs) have been recognised for their ability to kill multidrug-resistant bacteria and do not easily induce resistance, two features that make them very attractive as drug candidates. In addition, the overall peptide drug market is steadily growing, from US$18.9 billion in 2013 to US$23.7 billion in 2020. This has led to improved scale-up technologies and new large-scale GMP facilities and innovative drug administration regimes. Supported by the price increase for novel antimicrobials and the “ready to use” technology, antimicrobial peptides can become a viable option for urgently needed new antimicrobial drugs. In the last two decades of AMP research, it became clear that these molecules have multiple biological activities, like antimicrobial, antiparasitic, anticancer and immunomodulatory. In the same time period, multiple targets of AMPs for their antibacterial activities were discovered.

In this Special Issue of Microorganisms, we invite you to send contributions concerning any biological activities related to the therapeutic potential of antimicrobial peptides, including direct (e.g. killing of pathogens/parasites/cancer cells) and indirect (e.g. immunomodulatory effects) modes of action.

Dr. Kai Hilpert
Guest Editor

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Microorganisms is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2700 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • antimicrobial peptides
  • host defence peptides
  • multi-drug resistant bacteria
  • novel antimicrobials
  • immunomodulation
  • immunotherapy
  • anticancer peptides
  • antiparasitic peptides
  • antifungal peptides
  • wound healing peptides

Published Papers (4 papers)

Download All Papers
Order results
Result details
Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:

Research

13 pages, 3215 KiB  
Article
Identification of Genes Associated with Resistance to Persulcatusin, a Tick Defensin from Ixodes persulcatus
by So Shimoda, Junya Ito, Tasuke Ando, Ryuta Tobe, Kiyotaka Nakagawa and Hiroshi Yoneyama
Microorganisms 2024, 12(2), 412; https://doi.org/10.3390/microorganisms12020412 - 19 Feb 2024
Viewed by 826
Abstract
Antimicrobial peptides (AMPs) are present in a wide range of plants, animals, and microorganisms. Since AMPs are characterized by their effectiveness against emergent antibiotic-resistant bacteria, they are attracting attention as next-generation antimicrobial compounds that could solve the problem of drug-resistant bacteria. Persulcatusin (IP), [...] Read more.
Antimicrobial peptides (AMPs) are present in a wide range of plants, animals, and microorganisms. Since AMPs are characterized by their effectiveness against emergent antibiotic-resistant bacteria, they are attracting attention as next-generation antimicrobial compounds that could solve the problem of drug-resistant bacteria. Persulcatusin (IP), an antibacterial peptide derived from the hard tick Ixodes persulcatus, shows high antibacterial activity against various Gram- positive bacteria as well as multidrug-resistant bacteria. However, reports on the antibacterial action and resistance mechanisms of IP are scarce. In this study, we spontaneously generated mutants showing increased a minimum inhibitory concentration (MIC) of IP and analyzed their cross-resistance to other AMPs and antibiotics. We also used fluorescent probes to investigate the target of IP activity by evaluating IP-induced damage to the bacterial cytoplasmic membrane. Our findings suggest that the antimicrobial activity of IP on bacterial cytoplasmic membranes occurs via a mechanism of action different from that of known AMPs. Furthermore, we screened for mutants with high susceptibility to IP using a transposon mutant library and identified 16 genes involved in IP resistance. Our results indicate that IP, like other AMPs, depolarizes the bacterial cytoplasmic membrane, but it may also alter membrane structure and inhibit cell-wall synthesis. Full article
(This article belongs to the Special Issue Antimicrobial Peptides: Therapeutic Potentials 2.0)
►▼ Show Figures

Figure 1

21 pages, 3864 KiB  
Article
Antibiofilm Activity and Biocompatibility of Temporin-SHa: A Promising Antimicrobial Peptide for Control of Fluconazole-Resistant Candida albicans
by Luana Mendonça Dias, Eduardo Maffud Cilli, Karine Sousa Medeiros, Maria Carolina Oliveira de Arruda Brasil, Lina Maria Marin, Walter L. Siqueira and Ana Claudia Pavarina
Microorganisms 2024, 12(1), 99; https://doi.org/10.3390/microorganisms12010099 - 04 Jan 2024
Viewed by 859
Abstract
The aim of the study was to investigate the effect of antimicrobial peptides (AMPs) Hylin−a1, KR−12-a5, and Temporin-SHa in Candida albicans as well as the biocompatibility of keratinocytes spontaneously immortalized (NOK-si) and human gingival fibroblasts (FGH) cells. Initially, the susceptible (CaS—ATCC 90028) and [...] Read more.
The aim of the study was to investigate the effect of antimicrobial peptides (AMPs) Hylin−a1, KR−12-a5, and Temporin-SHa in Candida albicans as well as the biocompatibility of keratinocytes spontaneously immortalized (NOK-si) and human gingival fibroblasts (FGH) cells. Initially, the susceptible (CaS—ATCC 90028) and fluconazole-resistant (CaR—ATCC 96901) C. albicans strains were grown to evaluate the effect of each AMP in planktonic culture, biofilm, and biocompatibility on oral cells. Among the AMPs evaluated, temporin−SHa showed the most promising results. After 24 h of Temporin-SHa exposure, the survival curve results showed that CaS and CaR suspensions reduced 72% and 70% of cell viability compared to the control group. The minimum inhibitory/fungicide concentrations (MIC and MFC) showed that Temporin−SHa was able to reduce ≥50% at ≥256 µg/mL for both strains. The inhibition of biofilm formation, efficacy against biofilm formation, and total biomass assays were performed until 48 h of biofilm maturation, and Temporin-SHa was able to reduce ≥50% of CaS and CaR growth. Furthermore, Temporin−SHa (512 µg/mL) was classified as non-cytotoxic and slightly cytotoxic for NOK-si and FGH, respectively. Temporin−SHa demonstrated an anti-biofilm effect against CaS and CaR and was biocompatible with NOK-si and FGH oral cells in monolayer. Full article
(This article belongs to the Special Issue Antimicrobial Peptides: Therapeutic Potentials 2.0)
►▼ Show Figures

Figure 1

14 pages, 4747 KiB  
Article
Aquiluscidin, a Cathelicidin from Crotalus aquilus, and the Vcn-23 Derivative Peptide, Have Anti-Microbial Activity against Gram-Negative and Gram-Positive Bacteria
by Edwin Esaú Hernández-Arvizu, Teresa Monserrat Silis-Moreno, José Alejandro García-Arredondo, Angelina Rodríguez-Torres, José Antonio Cervantes-Chávez and Juan Mosqueda
Microorganisms 2023, 11(11), 2778; https://doi.org/10.3390/microorganisms11112778 - 15 Nov 2023
Viewed by 1097
Abstract
Anti-microbial peptides play a vital role in the defense mechanisms of various organisms performing functions that range from the elimination of microorganisms, through diverse mechanisms, to the modulation of the immune response, providing protection to the host. Among these peptides, cathelicidins, a well-studied [...] Read more.
Anti-microbial peptides play a vital role in the defense mechanisms of various organisms performing functions that range from the elimination of microorganisms, through diverse mechanisms, to the modulation of the immune response, providing protection to the host. Among these peptides, cathelicidins, a well-studied family of anti-microbial peptides, are found in various animal species, including reptiles. Due to the rise in anti-microbial resistance, these compounds have been suggested as potential candidates for developing new drugs. In this study, we identified and characterized a cathelicidin-like peptide called Aquiluscidin (Aq-CATH) from transcripts obtained from the skin and oral mucosa of the Querétaro’s dark rattlesnake, Crotalus aquilus. The cDNA was cloned, sequenced, and yielded a 566-base-pair sequence. Using bioinformatics, we predicted that the peptide precursor contains a signal peptide, a 101-amino-acid conserved cathelin domain, an anionic region, and a 34-amino-acid mature peptide in the C-terminal region. Aq-CATH and a derived 23-amino-acid peptide (Vcn-23) were synthesized, and their anti-microbial activity was evaluated against various species of bacteria in in vitro assays. The minimal inhibitory concentrations against bacteria ranged from 2 to 8 μg/mL for both peptides. Furthermore, at concentrations of up to 50 μM, they exhibited no significant hemolytic activity (<2.3% and <1.2% for Aquiluscidin and Vcn-23, respectively) against rat erythrocytes and displayed no significant cytotoxic activity at low concentrations (>65% cell viability at 25 µM). Finally, this study represents the first identification of an antimicrobial peptide in Crotalus aquilus, which belongs to the cathelicidin family and exhibits the characteristic features of these peptides. Both Aq-CATH and its derived molecule, Vcn-23, displayed remarkable inhibitory activity against all tested bacteria, highlighting their potential as promising candidates for further antimicrobial research. Full article
(This article belongs to the Special Issue Antimicrobial Peptides: Therapeutic Potentials 2.0)
►▼ Show Figures

Figure 1

22 pages, 5795 KiB  
Article
Discovery of Antimicrobial Peptides That Can Accelerate Culture Diagnostics of Slow-Growing Mycobacteria Including Mycobacterium tuberculosis
by Kai Hilpert, Tulika Munshi, Paula M. López-Pérez, Joana Sequeira-Garcia, Sven Hofmann and Tim J. Bull
Microorganisms 2023, 11(9), 2225; https://doi.org/10.3390/microorganisms11092225 - 02 Sep 2023
Cited by 3 | Viewed by 1329
Abstract
Antimicrobial peptides (AMPs) can directly kill Gram-positive bacteria, Gram-negative bacteria, mycobacteria, fungi, enveloped viruses, and parasites. At sublethal concentrations, some AMPs and also conventional antibiotics can stimulate bacterial response increasing their resilience, also called the hormetic response. This includes stimulation of growth, mobility, [...] Read more.
Antimicrobial peptides (AMPs) can directly kill Gram-positive bacteria, Gram-negative bacteria, mycobacteria, fungi, enveloped viruses, and parasites. At sublethal concentrations, some AMPs and also conventional antibiotics can stimulate bacterial response increasing their resilience, also called the hormetic response. This includes stimulation of growth, mobility, and biofilm production. Here, we describe the discovery of AMPs that stimulate the growth of certain mycobacteria. Peptide 14 showed a growth stimulating effect on Mycobacteria tuberculosis (MTB), M. bovis, M. avium subsp. paratuberculosis (MAP), M. marinum, M. avium-intracellulare, M. celatum, and M. abscessus. The effect was more pronounced at low bacterial inocula. The peptides induce a faster transition from the lag phase to the log phase and keep the bacteria longer in the log phase before entering stationary phase when compared to nontreated controls. In some cases, an increase in the division rate was observed. An initial screen using MAP and a collection of 75 peptides revealed 13 peptides with a hormetic effect. For MTB, a collection of 25 artificial peptides were screened and 13 were found to reduce the time to positivity (TTP) by at least 5%, improving growth. A screen of 43 naturally occurring peptides, 11 fragments of naturally occurring peptides and 5 designed peptides, all taken from the database APD3, identified a further 44 peptides that also lowered TTP by at least 5%. Lasioglossin LL-III (Bee) and Ranacyclin E (Frog) were the most active natural peptides, and the human cathelicidin LL37 fragment GF-17 and a porcine cathelicidin protegrin-1 fragment were the most active fragments of naturally occurring peptides. Peptide 14 showed growth-stimulating activity between 10 ng/mL and 10 µg/mL, whereas the stability-optimised Peptide 14D had a narrow activity range of 0.1–1 µg/mL. Peptides identified in this study are currently in commercial use to improve recovery and culture for the diagnostics of mycobacteria in humans and animals. Full article
(This article belongs to the Special Issue Antimicrobial Peptides: Therapeutic Potentials 2.0)
►▼ Show Figures

Figure 1

Show export options expand_more Show export options expand_less
Select all
Export citation of selected articles as:
 
Displaying articles 1-4
Back to TopTop