An LCI‐like protein APC ₂ protects ginseng root from Fusarium solani infection

Abstract

Aims: We aimed to purify an antimicrobial protein from Bacillus amyloliquefaciens FS6 culture supernatant, verify its antimicrobial activity against Fusarium solani and evaluate its biocontrol potential for ginseng root rot. Methods and Results: The antimicrobial protein was purified from FS6 culture supernatant using ammonium sulphate precipitation, anion exchange and gel chromatography. Based on mass spectrometry results, the purified protein was identified as an antimicrobial protein of the LCI family and was designated APC 2. The APC 2 recombinant protein expressed in Escherichia coli (BL21) significantly inhibited F. solani and decreased the infection and spread of F. solani in ginseng root. An overexpressing APC 2 strain FS6-APC 2 was constructed and shown to have enhanced antimicrobial activity compared to the wild-type strain FS6. Conclusions: The APC 2 protein shows strong antimicrobial activity against F. solani, reduces the incidence and severity of ginseng root rot caused by F. solani and exhibits a great biocontrol potential. Significance and Impact of the Study: This study reports the inhibitory activity of APC 2 protein (LCI family) against F. solani and its protective efficacy on ginseng root rot. These findings provide a scientific basis for future research on the biocontrol mechanism, as well as the development and application of FS6. 1996; Haas and D efago 2005; Nicolopoulou-Stamati et al. 2016). Biological control is environmentally friendly and less toxic to humans and animals. The application of biocontrol agents can minimize the progression towards pathogen resistance and represent the future of ginseng disease

The use of Bacillus spp. as bacterial biocontrol agents to control plant diseases

“…LCI peptide, purified from B. subtilis A014 and considered as bacteriocin-like inhibitory substances, have antibacterial activities against Xanthomonas campestris and R. solanacearum. The APC2 protein, a so-called LCI-like peptide produced by B. amyloliquefaciens FS6, has been shown to prevent Fusarium solani infection (Gong et al, 2011;Fan et al, 2018;Saikia et al, 2019;Wang et al, 2020a).…”

“…Surfactin production has been reported to be inhibited at pH 5 (Yi et al, 2017). Efficient synthesis of lipopeptides is favoured in mild-acidic to neutral environments, which is often the case for rhizosphere due to multiple processes related notably to plant exudation and root/microflora activity (Cosby et al, 1998;Akpa et al, 2001;Hinsinger et al, 2009;Wang et al, 2020a).…”

Regulating Root Fungal Community Using Mortierella alpina for Fusarium oxysporum Resistance in Panax ginseng

“…Currently, ginseng soil-borne diseases are mainly controlled by chemical agents. The frequent use of chemical fungicides has led to many problems, including increased pathogen resistance to fungicides, destruction of the soil microenvironment, high levels of toxic substances in ginseng, and environmental pollution ( Wang et al, 2021a ). Biological control is an environmentally friendly method of controlling plant diseases using beneficial microorganisms to regulate the microbiological composition of the soil.…”

Rhizospheric microbiota of suppressive soil protect plants against Fusarium solani infection

“…The antifungal activity of microbial strains against F. solani was tested by the plate confrontation method with slight modifications. 19 Bacterial strains were incubated in TS medium at 37 °C at 200 rpm for 12 h. Fungal strains were incubated in PD medium at 28 °C at 200 rpm for 5 days. The culture was centrifuged at 8000 × g for 10 min.…”