title: Metabolite and Mechanistic Basis of Antifungal Property Exhibited by Endophytic Bacillus amyloliquefaciens BmB 1.
abstract: Plants are ubiquitously colonized by endophytic microorganisms which contribute significantly to plant health through production of plant growth regulators or disease suppression. In the present study, an endophytic bacterial isolate designated as BmB 1 with significant antifungal and plant growth promoting properties was isolated from the stem tissue of Bacopa monnieri (L.) Pennell. The isolate was studied in detail for the molecular and chemical basis of its bioactivity which proved it to have the presence of surfactin, iturin, and type I polyketide synthase (PKS) genes. For the analysis of the chemical basis of antifungal property, extract of the isolate was initially checked for its activity on test pathogens and LC-MS/MS based analysis further confirmed the presence of bacillomycin (m/z (M+H(+)) 1031.8) and surfactin (m/z (M+H(+)) 1008.6 and 1022.6) in the extract prepared. The light microscopic and SEM analysis of the treated and untreated mycelia of the pathogens clearly revealed the hypal destruction caused by the compounds produced by the selected isolate. This confirms the ability of the organism to directly inhibit the growth of the tested pathogens. The GC-MS analysis also confirmed the isolate to have the presence of volatile compounds with the expected role to induce induced systemic resistance (ISR) of the plant. Because of the multitargeted antifungal property, the isolate which was identified as Bacillus amyloliquefaciens can have potential biocontrol applications.
authors.affiliation: School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560.
authors.forename: B
authors.initials: B
authors.lastname: Jasim
authors.affiliation: School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560.
authors.forename: Rosemin
authors.initials: R
authors.lastname: Benny
authors.affiliation: School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560.
authors.forename: Rohini
authors.initials: R
authors.lastname: Sabu
authors.affiliation: School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560.
authors.forename: Jyothis
authors.initials: J
authors.lastname: Mathew
authors.affiliation: School of Biosciences, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560. radhakrishnanek@mgu.ac.in.|Inter University Instrumentation Centre, Mahatma Gandhi University, PD Hills (PO), Kottayam, Kerala, India, 686 560. radhakrishnanek@mgu.ac.in.
authors.forename: E K
authors.initials: EK
authors.lastname: Radhakrishnan
mesh_terms: D000935:Antifungal Agents / Q000737:chemistry / Q000302:isolation & purification; D000069977:Bacillus amyloliquefaciens / Q000737:chemistry* / Q000302:isolation & purification / Q000378:metabolism; D034681:Bacopa / Q000254:growth & development / Q000378:metabolism* / Q000382:microbiology; D060026:Endophytes / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*; D055666:Lipopeptides / Q000737:chemistry / Q000302:isolation & purification; D010935:Plant Diseases / Q000235:genetics / Q000382:microbiology; D013559:Symbiosis / Q000235:genetics; D055549:Volatile Organic Compounds / Q000737:chemistry / Q000302:isolation & purification / Q000378:metabolism*
chemical_list: D000935:Antifungal Agents; D055666:Lipopeptides; D055549:Volatile Organic Compounds
keywords: B. monnieri; Endophytic B. amyloliquefaciens; GC-MS analysis; LC-MS/MS; PCR screening; Peptide antibiotics; SEM analysis