Expression of an Antimicrobial Peptide via the Chloroplast Genome to Control Phytopathogenic Bacteria and Fungi

Biosurfactant immunomodulatory activities in mammals, nematodes, and plants have been investigated. However, the immune activation property of biosurfactants in insects has not been reported. Therefore, here, we studied the defense response triggered by lipopeptides (fengycin and iturin A), glycolipids (rhamnolipid), and cyclic polypeptides (bacitracin) in the coleopteran insect, mealworm Tenebrio molitor. The in vitro antimicrobial activities against Gram-positive (Staphylococcus aureus) and Gram-negative (Escherichia coli) bacteria and fungi (Candida albicans) were assessed by mixing these pathogens with the hemolymph of biosurfactant-immune-activated larvae. E. coli growth was remarkably inhibited by this hemolymph. The antimicrobial peptide (AMP) induction results also revealed that all biosurfactants tested induced several AMPs, exclusively in hemocytes. The survivability analysis of T. molitor larvae challenged by E. coli (106 CFU/µL) at 24 h post biosurfactant-immune activation showed that fengycin, iturin A, and rhamnopid significantly increased survivability against E. coli. Biosurfactant-induced TmSpatzles activation was also monitored, and the results showed that TmSpz3 and TmSpz-like were upregulated in the hemocytes of iturin A-injected larvae, while TmSpz4 and TmSpz6 were upregulated in the fat bodies of the fengycin-, iturin A-, and rhamnolipid-injected larvae. Overall, these results suggest that lipopeptide and glycolipid biosurfactants induce the expression of AMPs in T. molitor via the activation of spätzle genes, thereby increasing the survivability of T. molitor against E. coli.

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Expression of the antimicrobial peptides in plants to control phytopathogenic bacteria and fungi

Plant Cell Reports ◽

10.1007/s00299-005-0102-5 ◽

2006 ◽

Vol 25 (6) ◽

pp. 561-572 ◽

Cited By ~ 42

Author(s):

S. V. Oard ◽

F. M. Enright

Keyword(s):

Antimicrobial Peptides ◽

Phytopathogenic Bacteria ◽

Bacteria And Fungi

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Chemical composition and antimicrobial activity of essential oils from Acantholippia deserticola, Artemisia proceriformis, Achillea micrantha and Libanotis buchtormensis against phytopathogenic bacteria and fungi

Natural Product Research ◽

10.1080/14786419.2015.1091453 ◽

2015 ◽

Vol 30 (17) ◽

pp. 1950-1955 ◽

Cited By ~ 16

Author(s):

Diego A. Sampietro ◽

Emilio F. Lizarraga ◽

Zharkyn A. Ibatayev ◽

Akerke B. Omarova ◽

Yerlan M. Suleimen ◽

...

Keyword(s):

Antimicrobial Activity ◽

Chemical Composition ◽

Essential Oils ◽

Phytopathogenic Bacteria ◽

Bacteria And Fungi

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A Systematic Study of the Stability, Safety, and Efficacy of the de novo Designed Antimicrobial Peptide PepD2 and Its Modified Derivatives Against Acinetobacter baumannii

Frontiers in Microbiology ◽

10.3389/fmicb.2021.678330 ◽

2021 ◽

Vol 12 ◽

Author(s):

Sung-Pang Chen ◽

Eric H-L Chen ◽

Sheng-Yung Yang ◽

Pin-Shin Kuo ◽

Hau-Ming Jan ◽

...

Keyword(s):

Antimicrobial Activity ◽

Antimicrobial Peptide ◽

Acinetobacter Baumannii ◽

De Novo ◽

Multidrug Resistant ◽

Hek293 Cells ◽

Amino Acid Residues ◽

Bacteria And Fungi ◽

The Stability

Searching for new antimicrobials is a pressing issue to conquer the emergence of multidrug-resistant (MDR) bacteria and fungi. Antimicrobial peptides (AMPs) usually have antimicrobial mechanisms different from those of traditional antibiotics and bring new hope in the discovery of new antimicrobials. In addition to antimicrobial activity, stability and target selectivity are important concerns to decide whether an antimicrobial peptide can be applied in vivo. Here, we used a simple de novo designed peptide, pepD2, which contains only three kinds of amino acid residues (W, K, L), as an example to evaluate how the residues and modifications affect the antimicrobial activity against Acinetobacter baumannii, stability in plasma, and toxicity to human HEK293 cells. We found that pepI2 with a Leu→Ile substitution can decrease the minimum bactericidal concentrations (MBC) against A. baumannii by one half (4 μg/mL). A D-form peptide, pepdD2, in which the D-enantiomers replaced the L-enantiomers of the Lys(K) and Leu(L) residues, extended the peptide half-life in plasma by more than 12-fold. PepD3 is 3-residue shorter than pepD2. Decreasing peptide length did not affect antimicrobial activity but increased the IC50 to HEK293 cells, thus increased the selectivity index (SI) between A. baumannii and HEK293 cells from 4.7 to 8.5. The chain length increase of the N-terminal acyl group and the Lys→Arg substitution greatly enhanced the hemolytic activity, hence those modifications are not good for clinical application. Unlike colistin, the action mechanism of our peptides relies on negatively charged lipids rather than lipopolysaccharides. Therefore, not only gram-negative bacteria but also gram-positive bacteria can be killed by our peptides.

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Methods of Determinating the Drug-resistant Strains in Phytopathogenic Bacteria and Fungi and its Epidemiology in the Field

Journal of Pesticide Science ◽

10.1584/jpestics.2.177 ◽

1977 ◽

Vol 2 (2) ◽

pp. 177-186 ◽

Cited By ~ 2

Author(s):

Hisashi SAKURAI

Keyword(s):

Drug Resistant ◽

Phytopathogenic Bacteria ◽

Resistant Strains ◽

Bacteria And Fungi ◽

Drug Resistant Strains

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Immunological detection of AcAMP antimicrobial peptide secreted by Aspergillus clavatus

Iranian Journal of Microbiology ◽

10.18502/ijm.v13i2.5985 ◽

2021 ◽

Author(s):

Ehsan Zamani ◽

Jamil Zargan ◽

Hossein Honar ◽

Abbas Hajizade ◽

Ashkan Haji Noor Mohammadi ◽

...

Keyword(s):

Escherichia Coli ◽

Antimicrobial Peptide ◽

Western Blotting ◽

Broad Spectrum ◽

Pathogenic Bacteria ◽

Expression Vector ◽

Multidrug Resistant ◽

Aspergillus Clavatus ◽

Natural Antimicrobial ◽

Bacteria And Fungi

Background and Objectives: Aspergillus clavatus antimicrobial peptide (AcAMP) is a fungi-derived peptide with a broad spectrum of activity against pathogenic bacteria and fungi. Natural antimicrobial peptides, including AcAMP, have attracted many attentions in the development of new natural antibiotics against pathogenic bacteria, especially multidrug resistant ones. Materials and Methods: In the present study, acamp gene was codon-optimized and chemically synthesized in pUC57 cloning vector, subcloned into pET28a (+) expression vector and transferred into competent Escherichia coli BL21 (DE3) cells. The expression of AcAMP was induced by addition of Isopropyl β- d-1-thiogalactopyranoside (IPTG) and the expressed peptide was purified by Ni-NTA. BALB/c mice were immunized with the purified peptide and the ability of the immunized mice sera for the detection of the native AcAMP secreted by A. clavatus IRAN 142C was examined through ELISA and Western blotting techniques. Results: Both ELISA and Western blotting demonstrated the ability of the sera of the immunized mice to detect the native AcAMP. Conclusion: The results of the present work show that the raised antibody against recombinant AcAMP can be used to detect AcAMP peptide, an issue which paves the way to develop detection kits for the detection of AcAMP-producing organisms, purification of this valuable peptide for further investigations.

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