title: Activation of the dormant secondary metabolite production by introducing gentamicin-resistance in a marine-derived Penicillium purpurogenum G59.
abstract: A new approach to activate silent gene clusters for dormant secondary metabolite production has been developed by introducing gentamicin-resistance to an originally inactive, marine-derived fungal strain Penicillium purpurogenum G59. Upon treatment of the G59 spores with a high concentration of gentamicin in aqueous DMSO, a total of 181 mutants were obtained by single colony isolation. In contrast to the strain G59, the EtOAc extracts of nine mutant cultures showed inhibitory effects on K562 cells, indicating that the nine mutants had acquired capability to produce antitumor metabolites. This was evidenced by TLC and HPLC analysis of EtOAc extracts of G59 and the nine mutants. Further isolation and characterization demonstrated that four antitumor secondary metabolites, janthinone (1), fructigenine A (2), aspterric acid methyl ester (3) and citrinin (4), were newly produced by mutant 5-1-4 compared to the parent strain G59, and which were also not found in the secondary metabolites of other Penicillium purpurogenum strains. However, Compounds 1-4 inhibited the proliferation of K562 cells with inhibition rates of 34.6% (1), 60.8% (2), 31.7% (3) and 67.1% (4) at 100 μg/mL, respectively. The present study demonstrated the effectiveness of a simple, yet practical approach to activate the production of dormant fungal secondary metabolites by introducing acquired resistance to aminoglycoside antibiotics, which could be applied to the studies for eliciting dormant metabolic potential of fungi to obtain cryptic secondary metabolites.
authors.affiliation: Beijing Institute of Pharmacology and Toxicology, 27 Tai-Ping Road, Haidian District, Beijing 100850, China.
authors.forename: Yun-Jing
authors.initials: YJ
authors.lastname: Chai
authors.affiliation: Beijing Institute of Pharmacology and Toxicology, 27 Tai-Ping Road, Haidian District, Beijing 100850, China.
authors.forename: Cheng-Bin
authors.initials: CB
authors.lastname: Cui
authors.affiliation: Beijing Institute of Pharmacology and Toxicology, 27 Tai-Ping Road, Haidian District, Beijing 100850, China.
authors.forename: Chang-Wei
authors.initials: CW
authors.lastname: Li
authors.affiliation: Beijing Institute of Pharmacology and Toxicology, 27 Tai-Ping Road, Haidian District, Beijing 100850, China.
authors.forename: Chang-Jing
authors.initials: CJ
authors.lastname: Wu
authors.affiliation: Beijing Institute of Pharmacology and Toxicology, 27 Tai-Ping Road, Haidian District, Beijing 100850, China.
authors.forename: Cong-Kui
authors.initials: CK
authors.lastname: Tian
authors.affiliation: Beijing Institute of Pharmacology and Toxicology, 27 Tai-Ping Road, Haidian District, Beijing 100850, China.
authors.forename: Wei
authors.initials: W
authors.lastname: Hua
mesh_terms: D000900:Anti-Bacterial Agents / Q000494:pharmacology*; D000903:Antibiotics, Antineoplastic / Q000096:biosynthesis / Q000302:isolation & purification / Q000494:pharmacology; D059001:Aquatic Organisms; D057005:Bioengineering; D049109:Cell Proliferation / Q000187:drug effects; D002851:Chromatography, High Pressure Liquid; D002855:Chromatography, Thin Layer; D004396:Coloring Agents; D024881:Drug Resistance, Bacterial / Q000235:genetics*; D005285:Fermentation; D005839:Gentamicins / Q000494:pharmacology*; D006801:Humans; D020014:K562 Cells; D008826:Microbial Sensitivity Tests; D005810:Multigene Family; D009154:Mutation / Q000235:genetics; D010407:Penicillium / Q000235:genetics* / Q000378:metabolism*; D010641:Phenotype; D012270:Ribosomes / Q000235:genetics; D013172:Spores, Fungal / Q000254:growth & development; D013778:Tetrazolium Salts; D013844:Thiazoles
chemical_list: D000900:Anti-Bacterial Agents; D000903:Antibiotics, Antineoplastic; D004396:Coloring Agents; D005839:Gentamicins; D013778:Tetrazolium Salts; D013844:Thiazoles; C022616:thiazolyl blue