AUTHOR=Xu Xiao-Yan , Shen Xiao-Ting , Yuan Xiao-Jie , Zhou Yuan-Ming , Fan Huan , Zhu Li-Ping , Du Feng-Yu , Sadilek Martin , Yang Jie , Qiao Bin , Yang Song 

TITLE=Metabolomics Investigation of an Association of Induced Features and Corresponding Fungus during the Co-culture of Trametes versicolor and Ganoderma applanatum

JOURNAL=Frontiers in Microbiology

VOLUME=8

YEAR=2018

URL=https://www.frontiersin.org/journals/microbiology/articles/10.3389/fmicb.2017.02647

DOI=10.3389/fmicb.2017.02647

ISSN=1664-302X

ABSTRACT=<p>The co-culture of <italic>Trametes versicolor</italic> and <italic>Ganoderma applanatum</italic> is a model of intense basidiomycete interaction, which induces many newly synthesized or highly produced features. Currently, one of the major challenges is an identification of the origin of induced features during the co-culture. Herein, we report a <sup>13</sup>C-dynamic labeling analysis used to determine an association of induced features and corresponding fungus even if the identities of metabolites were not available or almost nothing was known of biochemical aspects. After the co-culture of <italic>T. versicolor</italic> and <italic>G. applanatum</italic> for 10 days, the mycelium pellets of <italic>T. versicolor</italic> and <italic>G. applanatum</italic> were sterilely harvested and then mono-cultured in the liquid medium containing half fresh medium with <sup>13</sup>C-labeled glucose as carbon source and half co-cultured supernatants collected on day 10. <sup>13</sup>C-labeled metabolome analyzed by LC-MS revealed that 31 induced features including 3-phenyllactic acid and orsellinic acid were isotopically labeled in the mono-culture after the co-culture stimulation. Twenty features were derived from <italic>T. versicolor</italic>, 6 from <italic>G. applanatum</italic>, and 5 features were synthesized by both <italic>T. versicolor</italic> and <italic>G. applanatum</italic>. <sup>13</sup>C-labeling further suggested that 12 features such as previously identified novel xyloside [N-(4-methoxyphenyl)formamide 2-O-beta-D-xyloside] were likely induced through the direct physical interaction of mycelia. Use of molecular network analysis combined with <sup>13</sup>C-labeling provided an insight into the link between the generation of structural analogs and producing fungus. Compound <bold>1</bold> with m/z 309.0757, increased 15.4-fold in the co-culture and observed <sup>13</sup>C incorporation in the mono-culture of both <italic>T. versicolor</italic> and <italic>G. applanatum</italic>, was purified and identified as a phenyl polyketide, 2,5,6-trihydroxy-4, 6-diphenylcyclohex-4-ene-1,3-dione. The biological activity study indicated that this compound has a potential to inhibit cell viability of leukemic cell line U937. The current work sets an important basis for further investigations including novel metabolites discovery and biosynthetic capacity improvement.</p>