Analysis of Antimicrobial Peptide Metabolome of Bacterial Endophyte Isolated From Traditionally Used Medicinal Plant Millettia pachycarpa Benth

Abstract

Increasing prevalence of antimicrobial resistance (AMR) has posed a major health concern worldwide, and the addition of new antimicrobial agents is diminishing due to overexploitation of plants and microbial resources. Inevitably, alternative sources and new strategies are needed to find novel biomolecules to counter AMR and pandemic circumstances. The association of plants with microorganisms is one basic natural interaction that involves the exchange of biomolecules. Such a symbiotic relationship might affect the respective bio-chemical properties and production of secondary metabolites in the host and microbes. Furthermore, the discovery of taxol and taxane from an endophytic fungus, Taxomyces andreanae from Taxus wallachiana, has stimulated much research on endophytes from medicinal plants. A gram-positive endophytic bacterium, Paenibacillus peoriae IBSD35, was isolated from the stem of Millettia pachycarpa Benth. It is a rod-shaped, motile, gram-positive, and endospore-forming bacteria. It is neutralophilic as per Joint Genome Institute’s (JGI) IMG system analysis. The plant was selected based on its ethnobotany history of traditional uses and highly insecticidal properties. Bioactive molecules were purified from P. peoriae IBSD35 culture broth using 70% ammonium sulfate and column chromatography techniques. The biomolecule was enriched to 151.72-fold and the yield percentage was 0.05. Peoriaerin II, a highly potent and broad-spectrum antimicrobial peptide against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Candida albicans ATCC 10231 was isolated. LC-MS sequencing revealed that its N-terminal is methionine. It has four negatively charged residues (Asp + Glu) and a total number of two positively charged residues (Arg + Lys). Its molecular weight is 4,685.13 Da. It is linked to an LC-MS/MS inferred biosynthetic gene cluster with accession number A0A2S6P0H9, and blastp has shown it is 82.4% similar to fusaricidin synthetase of Paenibacillus polymyxa SC2. The 3D structure conformation of the BGC and AMP were predicted using SWISS MODEL homology modeling. Therefore, combining both genomic and proteomic results obtained from P. peoriae IBSD35, associated with M. pachycarpa Benth., will substantially increase the understanding of antimicrobial peptides and assist to uncover novel biological agents.

Integrated genomics and proteomics analysis of Paenibacillus peoriae IBSD35 and insights into its antimicrobial characteristics

“…Paenibacillus peoriae IBSD35 from the stock solution has retained antimicrobial activity against S. aureus ATCC 25923, indicating its inherent antimicrobial potential 66 . Endospore forming traits may help its endophytic association with the host plant 67 .…”

“…An endophytic bacterium P. peoriae IBSD35 isolated from the stem of M. pachycarpa in our previous experiment was picked in our present context 7 – 9 , 66 . It was sub-cultured from 15% phosphate buffer saline (PBS) glycerol stock preserved in the Institute of Bioresources and Sustainable Development-Microbial Resources Division (IBSD-MRC) repository (Accession No.…”

“…2 l of the production medium (pH 7 ± 2) was inoculated with an overnight grown culture of P. peoriae IBSD35 and incubated in a shaker incubator at 80 rpm (Eppendorf innova R42 Rotary shaker). Its optimum pH, OD, and temperature concerning antimicrobial activity were determined by aseptically aspirating out the inoculum from the fermentation broth 66 . The production medium was harvested by centrifugation at 3200× g for 15 min at 4 °C.…”

Plant Antimicrobial Peptides (PAMPs): Features, Applications, Production, Expression, and Challenges

“…The work offers great promise for the use of plant AMPs in the regulatory processes of evolutionary importance to exploit them as next-generation molecules against pathogens. Ngashangva, Mukherjee [112] analyzed the AMP's metabolome of bacterial endophyte isolated from the traditionally used medicinal plant Millettia pachycarpa Benth. The outcome of this work revealed that both genomic and proteomic results would substantially increase the understanding of AMPs and assist the discovery of novel biological agents.…”

Comparative genomic and functional analyses of Paenibacillus peoriae ZBSF16 with biocontrol potential against grapevine diseases, provide insights into its genes related to plant growth-promoting and biocontrol mechanisms

“…Previously, P. peoriae was reported to act as a plant growth-promoting rhizobacteria (PGPR), which can produce biofilms, stably colonize the rhizosphere of plants and compete with other microbiota ( Von der Weid et al, 2003 ; Vejan et al, 2016 ; Jiang et al, 2022 ). Meanwhile, P. peoriae has the ability to act as a biological control agent against many plant pathogens, including Fusarium spp., Diplodia macrospora , D. maydis , Verticillium dahlia , Rhizoctonia solani , Colletotrichum gloeosporioides , and C. graminicola ( Von der Weid et al, 2003 ; Yadav D. et al, 2021 ; Jiang et al, 2022 ), and even the antimicrobial peptide purified from P. peoriae could protect against Staphylococcus aureus , Escherichia coli , and Candida albicans ( Ngashangva et al, 2021 ).…”