{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,10,7]],"date-time":"2026-10-07T17:56:09Z","timestamp":1791395769498,"version":"4.3.3"},"reference-count":34,"publisher":"MDPI AG","issue":"4","license":[{"start":{"date-parts":[[2015,4,22]],"date-time":"2015-04-22T00:00:00Z","timestamp":1429660800000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Marine Drugs"],"abstract":"<jats:p>Introduction of neomycin-resistance into a marine-derived, wild-type  Penicillium purpurogenum G59 resulted in activation of silent biosynthetic pathways for the secondary metabolite production. Upon treatment of G59 spores with neomycin and dimethyl sulfoxide (DMSO), a total of 56 mutants were obtained by single colony isolation. The acquired resistance of mutants to neomycin was testified by the resistance test.  In contrast to the G59 strain, the EtOAc extracts of 28 mutants inhibited the human cancer K562 cells, indicating that the 28 mutants have acquired the capability to produce bioactive metabolites. HPLC-photodiode array detector (PDAD)-UV and HPLC-electron spray ionization (ESI)-MS analyses further indicated that diverse secondary metabolites have been newly produced in the bioactive mutant extracts. Followed isolation and characterization demonstrated that five bioactive secondary metabolites, curvularin (1), citrinin (2), penicitrinone A (3), erythro-23-O-methylneocyclocitrinol (4) and 22E-7\u03b1-methoxy-5\u03b1, 6\u03b1-epoxyergosta-8(14),22-dien-3\u03b2-ol (5), were newly produced by a mutant, 4-30, compared to the G59 strain. All 1\u20135 were also not yet found in the secondary metabolites of other wild type P. purpurogenum strains. Compounds 1\u20135 inhibited human cancer K562, HL-60, HeLa and BGC-823 cells to varying extents. Both present bioassays and  chemical investigations demonstrated that the introduction of neomycin-resistance into the  marine-derived fungal G59 strain could activate silent secondary metabolite production. The present work not only extended the previous DMSO-mediated method for introducing drug-resistance in fungi both in DMSO concentrations and antibiotics, but also additionally exemplified effectiveness of this method for activating silent fungal secondary metabolites. This method could be applied to other fungal isolates to elicit their metabolic potentials  to investigate secondary metabolites from silent biosynthetic pathways.<\/jats:p>","DOI":"10.3390\/md13042465","type":"journal-article","created":{"date-parts":[[2015,4,22]],"date-time":"2015-04-22T12:14:23Z","timestamp":1429704863000},"page":"2465-2487","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":36,"title":["Activation of the Silent Secondary Metabolite Production by Introducing Neomycin-Resistance in a Marine-Derived Penicillium purpurogenum G59"],"prefix":"10.3390","volume":"13","author":[{"ORCID":"https:\/\/orcid.org\/0000-0001-9196-8532","authenticated-orcid":false,"given":"Chang-Jing","family":"Wu","sequence":"first","affiliation":[{"name":"State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China"},{"name":"Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education,  School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University,  Shenyang 110016, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Le","family":"Yi","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Cheng-Bin","family":"Cui","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China"},{"name":"Key Laboratory of Structure-Based Drug Design & Discovery of Ministry of Education,  School of Traditional Chinese Materia Medica, Shenyang Pharmaceutical University,  Shenyang 110016, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Chang-Wei","family":"Li","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Nan","family":"Wang","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Xiao","family":"Han","sequence":"additional","affiliation":[{"name":"State Key Laboratory of Toxicology and Medical Countermeasures, Beijing Institute of Pharmacology and Toxicology, Beijing 100850, China"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2015,4,22]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"2745","DOI":"10.2174\/15680266113136660197","article-title":"New and highly potent antitumor natural products from marine-derived fungi: Covering the period from 2003 to 2012","volume":"13","author":"Pejin","year":"2013","journal-title":"Curr. 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