Clarification of the Antagonistic Effect of the Lipopeptides Produced by Bacillus amyloliquefaciens BPD1 against Pyricularia oryzae via In Situ MALDI-TOF IMS Analysis

Abstract

This study tried to clarify the antagonistic effect of the lipopeptides secreted by Bacillus amyloliquefaciens strain BPD1 (Ba-BPD1) against Pyricularia oryzae Cavara (PO). To determine the major antifungal lipopeptides effective against PO, single and dual cultures were carried out in solid-state media. The matrix-assisted laser desorption/ionization-time of flight imaging mass spectrometry (MALDI-TOF IMS) was used to identify the most effective lipopeptide in situ. Meanwhile, the morphology of pathogen fungi treated with lipopeptides was observed via the SEM. Of the three lipopeptide families, surfactin, iturin, and fengycin, the last was identified as the most effective for inhibiting mycelium growth and conidial germination of PO. The conidia and hyphae of fengycin-treated PO were shown to become deformed and tumorous under exposure. This study provides insights into the antagonistic effect of Ba-BPD1 against fungal phytopathogens. Such insights are helpful in the development of reagents for biological control applications.

Identification and ultra‐high‐performance liquid chromatography coupled with high‐resolution mass spectrometry characterization of biosurfactants, including a new surfactin, isolated from oil‐contaminated environments

“…2). The m/z 370.2570 corresponded to glutamic acid residue with aliphatic fatty acid chains containing 15 carbons, indicating similarities between the proposed surfactin A (C15) produced by all five selected samples and literature surfactin (Liao et al, 2016). S1-S17.…”

“…). The m/z 370.2570 corresponded to glutamic acid residue with aliphatic fatty acid chains containing 15 carbons, indicating similarities between the proposed surfactin A (C15) produced by all five selected samples and literature surfactin (Liao et al ., ). Additional fragment ions [M+H] + confirmed the presence of amino acid residues sequence as m/z 227.1750 [Leu+Leu+H] + , m/z 328.1862 [Leu+Asp+Val+H] + , m/z 441.2699 [Leu+Asp+Val+Leu+H] + and m/z 554.3536 [Leu+Asp+Val+Leu+Leu+H] + .…”

Soil Bacteria Isolated From Tunisian Arid Areas Show Promising Antimicrobial Activities Against Gram-Negatives

“…The m/z 370.2595 corresponded to glutamic acid residue with aliphatic fatty acid chains containing 15 carbons, indicating similarities between the proposed surfactin A (C15) produced by Bacillus sp. M21a and the known surfactin ( Liao et al, 2016 ). Additional fragment ions [M + H] + confirmed the presence of amino acids sequence as m/ z 227.1766 [Leu + Leu + H] + , m/z 328.1873 [Leu + Asp + Val + H] + , m/z 441.2721 [Leu + Asp + Val + Leu + H] + , and m/z 554.3560 [Leu + Asp + Val + Leu + Leu + H] + (Supplementary Figure 5 ).…”

Rice phyllosphere bacteria producing antifungal compounds as biological control agents of blast disease

“…Suriani et al (2015) declared that the alteration of hyphae and spores size of P. oryzae caused by lysis of mycelium cell phenomenon. Additionally, Liao et al (2016) also informed that the application of fengycin from B. amyloliquifaciens BPD1 toward P. oryzae resulted in swollen and cracked mycelium. The inhibition of fungal growth by antifungal compounds from isolate STGG 14 informs us that the crude extract displays fungistatic mode of action, because the extracted antifungal compounds only inhibit the growth of P. oryzae race 173 without killing the pathogen.…”