Isolation and Characterization of an Endophytic Fungus Colletotrichum coccodes Producing Tyrosol From Houttuynia cordata Thunb. Using ITS2 RNA Secondary Structure and Molecular Docking Study

Abstract

An endophytic fungus isolated from healthy leaf tissues of Houttuynia cordata Thunb., an ethnomedicinal plant of North East India, showed a considerable amount of antimicrobial activity. The ethyl acetate extract of the fungal culture filtrates displayed promising antimicrobial activity against a panel of clinically significant pathogens including Candida albicans, Staphylococcus aureus, Escherichia coli, and Pseudomonas aeruginosa. Bioassay guided purification of the organic extract using column and thin layer chromatography yielded a pure homogenous compound which was identified using spectroscopic methods (essentially by 1H NMR and MS) as tyrosol, a well-known phenylethanoid present in several natural sources. Besides, molecular docking studies against tyrosyl tRNA synthetases (TyrRS) of S. aureus (PDB ID: 1JIL) and E. coli (PDB ID: 1VBM), and CYP45014α-lanosterol demethylase (CYP51) of C. albicans (PDB ID: 5FSA) revealed tyrosol has a strong binding affinity with the enzyme active site residues. The fungus was identified as Colletotrichum sp. and characterized by its genomic ITS rDNA and ITS2 sequences. Phylogenetic analyses showed clustering of our isolate with Colletotrichum coccodes. Species of Colletotrichum are also reported to be plant pathogens. Therefore, to confirm the endophytic lifestyle of the isolate, ITS2 RNA secondary structure study was undertaken. The result indicated our isolate exhibited differences in the folding pattern as well as in motif structures when compared to those of pathogenic C. coccodes. The findings indicated that endophytic fungi harboring H. cordata could be explored as a potent source of antimicrobial agents.

Truncatenolide, a Bioactive Disubstituted Nonenolide Produced by Colletotrichum truncatum, the Causal Agent of Anthracnose of Soybean in Argentina: Fungal Antagonism and SAR Studies

“…Recently, compound 3 was also produced by an endophytic fungus collected in India from Houttuynia cordata Thunb. Tyrosol showed strong antimicrobial activity against a plethora of clinically severe pathogens such as Staphylococcus aureus, Candida albicans, Pseudomonas aeruginosa, and Escherichia coli . Acetyltyramine ( N -(4-hydroxyphenetyl)­acetamide) belongs to the alkylamide family of naturally occurring compounds found in at least 33 plant families.…”

“…Tyrosol showed strong antimicrobial activity against a plethora of clinically severe pathogens such as Staphylococcus aureus, Candida albicans, Pseudomonas aeruginosa, and Escherichia coli. 46 Acetyltyramine (N-(4-hydroxyphenetyl)acetamide) belongs to the alkylamide family of naturally occurring compounds found in at least 33 plant families. Considering their structural variability associated with important biological activities (such as antimicrobial, immunomodulatory, larvicidal, antiviral, antioxidant, and insecticidal properties), they were recently the object of an extensive review focused essentially on cinnamoyltyramine.…”

Rapid Detection of Candida tropicalis in Clinical Samples From Different Sources Using RPA-LFS

“…Several studies have evaluated various methods for detecting C. tropicalis infection in clinical samples from different sources. Among these methods, the ITS2 gene was most frequently used as a detection target (Turenne et al, 1999;Talukdar et al, 2021). Therefore, we designed a pair of primer probes to detect C. tropicalis.…”

Metabolites of medicine food homology-derived endophytic fungi and their activities

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