Structure-function relationships in bombinins H, antimicrobial peptides from Bombina skin secretions☆

Hevein-like antimicrobial peptides (AMPs) comprise a family of plant AMPs with antifungal activity, which harbor a chitin-binding site involved in interactions with chitin of fungal cell walls. However, the mode of action of hevein-like AMPs remains poorly understood. This work reports the structure–function relationship in WAMPs—hevein-like AMPs found in wheat (Triticum kiharae Dorof. et Migush.) and later in other Poaceae species. The effect of WAMP homologues differing at position 34 and the antifungal activity of peptide fragments derived from the central, N- and C-terminal regions of one of the WAMPs, namely WAMP-2, on spore germination of different plant pathogenic fungi were studied. Additionally, the ability of WAMP-2-derived peptides to potentiate the fungicidal effect of tebuconazole, one of the triazole fungicides, towards five cereal-damaging fungi was explored in vitro by co-application of WAMP-2 fragments with Folicur® EC 250 (25% tebuconazole). The antifungal activity of WAMP homologues and WAMP-2-derived peptides varied depending on the fungus, suggesting multiple modes of action for WAMPs against diverse pathogens. Folicur® combined with the WAMP-2 fragments inhibited the spore germination at a much greater level than the fungicide alone, and the type of interactions was either synergistic or additive, depending on the target fungus and concentration combinations of the compounds. The combinations, which resulted in synergism and drastically enhanced the sensitivity to tebuconazole, were revealed for all five fungi by a checkerboard assay. The ability to synergistically interact with a fungicide and exacerbate the sensitivity of plant pathogenic fungi to a commercial antifungal agent is a novel and previously uninvestigated property of hevein-like AMPs.

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Development of Antimicrobial Peptides from Amphibians

Antibiotics ◽

10.3390/antibiotics9110772 ◽

2020 ◽

Vol 9 (11) ◽

pp. 772

Author(s):

Maria Luisa Mangoni ◽

Bruno Casciaro

Keyword(s):

Xenopus Laevis ◽

Antimicrobial Peptides ◽

Anuran Species ◽

Skin Secretions

Since the discovery of magainins from the skin secretions of the African toad Xenopus laevis by Michael Zasloff in 1987, an increasing number of antimicrobial peptides (AMPs) has been identified in different anuran species and studied in detail [...]

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Development and Challenges of Antimicrobial Peptides for Therapeutic Applications

Antibiotics ◽

10.3390/antibiotics9010024 ◽

2020 ◽

Vol 9 (1) ◽

pp. 24 ◽

Cited By ~ 34

Author(s):

Charles H. Chen ◽

Timothy K. Lu

Keyword(s):

Antimicrobial Peptides ◽

Soil Bacteria ◽

Bacterial Infections ◽

Mechanisms Of Action ◽

The Body ◽

Antimicrobial Drugs ◽

Skin Secretions ◽

Approved Drugs ◽

Topical Medications ◽

Fda Approved Drugs

More than 3000 antimicrobial peptides (AMPs) have been discovered, seven of which have been approved by the U.S. Food and Drug Administration (FDA). Now commercialized, these seven peptides have mostly been utilized for topical medications, though some have been injected into the body to treat severe bacterial infections. To understand the translational potential for AMPs, we analyzed FDA-approved drugs in the FDA drug database. We examined their physicochemical properties, secondary structures, and mechanisms of action, and compared them with the peptides in the AMP database. All FDA-approved AMPs were discovered in Gram-positive soil bacteria, and 98% of known AMPs also come from natural sources (skin secretions of frogs and toxins from different species). However, AMPs can have undesirable properties as drugs, including instability and toxicity. Thus, the design and construction of effective AMPs require an understanding of the mechanisms of known peptides and their effects on the human body. This review provides an overview to guide the development of AMPs that can potentially be used as antimicrobial drugs.

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Antimicrobial peptides in silkworm

Animal Biology ◽

10.1163/15707563-20191065 ◽

2019 ◽

Vol 69 (4) ◽

pp. 391-410 ◽

Cited By ~ 1

Author(s):

Zhi Li ◽

Yan Ma ◽

Xuan Liu ◽

Yi Li ◽

Fangyin Dai

Keyword(s):

Antioxidant Activity ◽

Clinical Practice ◽

Antimicrobial Peptides ◽

Structure Function ◽

Broad Spectrum ◽

Antibacterial Properties ◽

Antimicrobial Activities ◽

Vital Role ◽

Bacteria Resistance

Abstract Antimicrobial peptides (AMPs) are a type of small molecular proteins that play a vital role in the resistance to alien pathogens. AMPs are widespread in bacteria, archaea, protists, fungi, plants and animals. AMPs have a broad spectrum of antimicrobial activities and they rarely induce bacteria resistance; thus, they are thought to be good candidates for antibiotics in clinical practice. Recently, AMPs are increasingly attracting attention because of their outstanding features and functions. In addition to their known antibacterial properties, some kinds of AMPs have also been reported to have antiviral, anticancer, antiparasitic, and antioxidant activity. In this review, we introduce the diversity of AMPs, including their structure, function and related mechanisms. We focus primarily on recent studies of silkworm AMPs and summarize their classification, activities and possible mechanisms. Finally, based on the review, probable directions and perspectives for studies of the AMPs of silkworm are discussed and proposed.

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Insights into the Effect of the Membrane Environment on the Three-dimensional Structure-function Relationship of Antimicrobial Peptides

Biophysical Journal ◽

10.1016/j.bpj.2019.11.1394 ◽

2020 ◽

Vol 118 (3) ◽

pp. 236a

Author(s):

William J. Zamora ◽

Silvana De Souza ◽

Frances Separovic ◽

Fco. Javier Luque

Keyword(s):

Antimicrobial Peptides ◽

Structure Function ◽

Three Dimensional ◽

Dimensional Structure ◽

Three Dimensional Structure ◽

Structure Function Relationship ◽

Function Relationship ◽

Relationship Of

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Antimicrobial Peptides in Frog Skin Secretions

Methods in Molecular Biology - Antimicrobial Peptides ◽

10.1007/978-1-60761-594-1_1 ◽

2009 ◽

pp. 3-14 ◽

Cited By ~ 30

Author(s):

J. Michael Conlon ◽

Agnes Sonnevend

Keyword(s):

Antimicrobial Peptides ◽

Frog Skin ◽

Skin Secretions

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Using fluorescence microscopy to shed light on the mechanisms of antimicrobial peptides

Future Medicinal Chemistry ◽

10.4155/fmc-2019-0095 ◽

2019 ◽

Vol 11 (18) ◽

pp. 2445-2458

Author(s):

Anne K Buck ◽

Donald E Elmore ◽

Louise EO Darling

Keyword(s):

Fluorescence Microscopy ◽

Antimicrobial Peptides ◽

Structure Function ◽

Temporal Resolution ◽

Cellular Localization ◽

Bacterial Resistance ◽

Mechanisms Of Action ◽

Membrane Interaction ◽

Research Questions ◽

Shed Light

Antimicrobial peptides (AMPs) are promising in the fight against increasing bacterial resistance, but the development of AMPs with enhanced activity requires a thorough understanding of their mechanisms of action. Fluorescence microscopy is one of the most flexible and effective tools to characterize AMPs, particularly in its ability to measure the membrane interactions and cellular localization of peptides. Recent advances have increased the scope of research questions that can be addressed via microscopy through improving spatial and temporal resolution. Unique combinations of fluorescent labels and dyes can simultaneously consider different aspects of peptide–membrane interaction mechanisms. This review emphasizes the central role that fluorescence microscopy will continue to play in the interrogation of AMP structure–function relationships and the engineering of more potent peptides.

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