title: An Insight into the Secondary Metabolism of Muscodor yucatanensis: Small-Molecule Epigenetic Modifiers Induce Expression of Secondary Metabolism-Related Genes and Production of New Metabolites in the Endophyte.
abstract: Muscodor spp. are proficient producers of bioactive volatile organic compounds (VOCs) with many potential applications. However, all members of this genus produce varying amounts and types of VOCs which suggests the involvement of epigenetics as a possible explanation. The members of this genus are poorly explored for the production of soluble compounds (extrolites). In this study, the polyketide synthase (PKS) and non-ribosomal peptide synthetase (NRPS) genes from an endophyte, Muscodor yucatanensis Ni30, were cloned and sequenced. The PKS genes belonged to reduced, partially reduced, non-reduced, and highly reduced subtypes. Strains over-expressing PKS genes were developed through the use of small-molecule epigenetic modifiers (suberoylanilide hydroxamic acid (SAHA) and 5-azacytidine). The putative epigenetic variants of this organism differed considerably from the wild type in morphological features and cultural characteristics as well as metabolites that were produced. Each variant produced a different set of VOCs distinct from the wild type, and several VOCs including methyl 3-(3,5-di-tert-butyl-4-hydroxyphenyl)hexane-2,4-diol and 2-carboxymethyl-3-n-hexylmaleic appeared in the variant strains, the production of which could be attributed to the activity of otherwise silent PKS genes. The bioactive extrolite brefeldin A was isolated and characterized from the wild type. However, this metabolite was not detected in EV-1, but instead, two other products were isolated and characterized as ergosterol and xylaguaianol C. Hence, M. yucatanensis has the genetic potential to produce several previously undetectable VOCs and organic solvent soluble products. It is also the case that small-molecule epigenetic modifiers can be used to produce stable variant strains of fungi with the potential to produce new molecules. Finally, this work hints to the prospect that the epigenetics of an endophytic microorganism can be influenced by any number of environmental and chemical factors associated with its host plant which may help to explain the enormous chemical diversity of secondary metabolic products found in Muscodor spp.
authors.affiliation: Microbial Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.
authors.forename: Masroor
authors.initials: M
authors.lastname: Qadri
authors.affiliation: Natural Product Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.|Academy of Scientific and Innovative Research (AcSIR), CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.
authors.forename: Yedukondalu
authors.initials: Y
authors.lastname: Nalli
authors.affiliation: Natural Product Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.|Academy of Scientific and Innovative Research (AcSIR), CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.
authors.forename: Shreyans K
authors.initials: SK
authors.lastname: Jain
authors.affiliation: Academy of Scientific and Innovative Research (AcSIR), CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.|Fermentation Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.
authors.forename: Asha
authors.initials: A
authors.lastname: Chaubey
authors.affiliation: Natural Product Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.|Academy of Scientific and Innovative Research (AcSIR), CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.
authors.forename: Asif
authors.initials: A
authors.lastname: Ali
authors.affiliation: Department of Plant Sciences, Montana State University, Bozeman, MT, 59717, USA.
authors.forename: Gary A
authors.initials: GA
authors.lastname: Strobel
authors.affiliation: Natural Product Chemistry Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.|Academy of Scientific and Innovative Research (AcSIR), CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India.
authors.forename: Ram A
authors.initials: RA
authors.lastname: Vishwakarma
authors.affiliation: Microbial Biotechnology Division, CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India. srhassan@iiim.ac.in.|Academy of Scientific and Innovative Research (AcSIR), CSIR-Indian Institute of Integrative Medicine, Canal Road, Jammu Tawi, 180001, India. srhassan@iiim.ac.in.
authors.forename: Syed
authors.initials: S
authors.lastname: Riyaz-Ul-Hassan
mesh_terms: D000595:Amino Acid Sequence; D001374:Azacitidine / Q000378:metabolism; D020126:Brefeldin A / Q000378:metabolism; D004271:DNA, Fungal; D060026:Endophytes / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism; D057890:Epigenomics; D004875:Ergosterol / Q000378:metabolism; D015966:Gene Expression Regulation, Fungal / Q000235:genetics*; D005800:Genes, Fungal; D006877:Hydroxamic Acids / Q000378:metabolism; D010453:Peptide Synthases / Q000737:chemistry / Q000235:genetics; D010641:Phenotype; D010802:Phylogeny; D048630:Polyketide Synthases / Q000737:chemistry / Q000235:genetics; D016133:Polymerase Chain Reaction / Q000379:methods; D011487:Protein Conformation; D064210:Secondary Metabolism / Q000235:genetics*; D016415:Sequence Alignment; D055549:Volatile Organic Compounds / Q000032:analysis / Q000737:chemistry / Q000378:metabolism; D000077337:Vorinostat; D013098:Xylariales / Q000145:classification / Q000201:enzymology* / Q000235:genetics* / Q000378:metabolism
chemical_list: D004271:DNA, Fungal; D006877:Hydroxamic Acids; D055549:Volatile Organic Compounds; D020126:Brefeldin A; D000077337:Vorinostat; D048630:Polyketide Synthases; D010453:Peptide Synthases; C104385:non-ribosomal peptide synthase; D001374:Azacitidine; D004875:Ergosterol
keywords: Brefeldin A; Epigenetic modifiers; Ergosterol; Muscodor; Polyketide synthase; Xylaguaianol C