{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,11,5]],"date-time":"2026-11-05T12:56:30Z","timestamp":1793883390518,"version":"4.7.0"},"reference-count":77,"publisher":"MDPI AG","issue":"7","license":[{"start":{"date-parts":[[2023,6,28]],"date-time":"2023-06-28T00:00:00Z","timestamp":1687910400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"name":"German Federal State of North Rhine\u2013Westphalia and the European Union","award":["GRK2341"],"award-info":[{"award-number":["GRK2341"]}]},{"name":"European Regional Development Fund, Investing in Your Future (Research Infrastructure \u2018Center for System-based Antibiotic Research (CESAR)\u2019","award":["GRK2341"],"award-info":[{"award-number":["GRK2341"]}]},{"DOI":"10.13039\/501100001659","name":"German Research Foundation (DFG)","doi-asserted-by":"publisher","award":["GRK2341"],"award-info":[{"award-number":["GRK2341"]}],"id":[{"id":"10.13039\/501100001659","id-type":"DOI","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["Antibiotics"],"abstract":"<jats:p>Bacteria of the genus Streptomyces produce various specialized metabolites. Single biosynthetic gene clusters (BGCs) can give rise to different products that can vary in terms of their biological activities. For example, for alnumycin and the shunt product K115, antimicrobial activity was described, while no antimicrobial activity was detected for the shunt product 1,6-dihydro 8-propylanthraquinone. To investigate the antibacterial activity of 1,6-dihydro 8-propylanthraquinone, we produced alnumycin and 1,6-dihydro 8-propylanthraquinone from a Streptomyces isolate containing the alnumycin BGC. The strain was cultivated in liquid glycerol\u2013nitrate\u2013casein medium (GN), and both compounds were isolated using an activity and mass spectrometry-guided purification. The structures were validated via nuclear magnetic resonance (NMR) spectroscopy. A minimal inhibitory concentration (MIC) test revealed that 1,6-dihydro 8-propylanthraquinone exhibits antimicrobial activity against E.\u00a0coli \u0394tolC, B.\u00a0subtilis, an S.\u00a0aureus type strain, and a vancomycin intermediate-resistance S. aureus strain (VISA). Activity of 1,6-dihydro 8-propylanthraquinone against E.\u00a0coli \u0394tolC was approximately 10-fold higher than that of alnumycin. We were unable to confirm gyrase inhibition for either compound and believe that the modes of action of both compounds are worth reinvestigating.<\/jats:p>","DOI":"10.3390\/antibiotics12071116","type":"journal-article","created":{"date-parts":[[2023,6,29]],"date-time":"2023-06-29T00:41:45Z","timestamp":1687999305000},"page":"1116","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":7,"title":["Characterization of the Antibacterial Activity of Quinone-Based Compounds Originating from the Alnumycin Biosynthetic Gene Cluster of a Streptomyces Isolate"],"prefix":"10.3390","volume":"12","author":[{"ORCID":"https:\/\/orcid.org\/0009-0000-0660-791X","authenticated-orcid":false,"given":"Leonie","family":"Sagurna","sequence":"first","affiliation":[{"name":"Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2193-5422","authenticated-orcid":false,"given":"Sascha","family":"Heinrich","sequence":"additional","affiliation":[{"name":"Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Lara-Sophie","family":"Kaufmann","sequence":"additional","affiliation":[{"name":"Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9722-4435","authenticated-orcid":false,"given":"Christian","family":"R\u00fcckert-Reed","sequence":"additional","affiliation":[{"name":"Technology Platform Genomics, Center for Biotechnology, Bielefeld University, 33594 Bielefeld, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Tobias","family":"Busche","sequence":"additional","affiliation":[{"name":"Technology Platform Genomics, Center for Biotechnology, Bielefeld University, 33594 Bielefeld, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Alexander","family":"Wolf","sequence":"additional","affiliation":[{"name":"Lead Discovery Center GmbH, 44227 Dortmund, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-5537-438X","authenticated-orcid":false,"given":"Jan","family":"Eickhoff","sequence":"additional","affiliation":[{"name":"Lead Discovery Center GmbH, 44227 Dortmund, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Bert","family":"Klebl","sequence":"additional","affiliation":[{"name":"Lead Discovery Center GmbH, 44227 Dortmund, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-9052-1998","authenticated-orcid":false,"given":"J\u00f6rn","family":"Kalinowski","sequence":"additional","affiliation":[{"name":"Technology Platform Genomics, Center for Biotechnology, Bielefeld University, 33594 Bielefeld, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Julia E.","family":"Bandow","sequence":"additional","affiliation":[{"name":"Applied Microbiology, Faculty of Biology and Biotechnology, Ruhr University Bochum, 44780 Bochum, Germany"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2023,6,28]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"770","DOI":"10.1021\/acs.jnatprod.9b01285","article-title":"Natural Products as sources of new drugs over the nearly four decades from 01\/1981 to 09\/2019","volume":"83","author":"Newman","year":"2020","journal-title":"J. Nat. Prod."},{"key":"ref_2","doi-asserted-by":"crossref","first-page":"311","DOI":"10.1021\/np200906s","article-title":"Natural products as sources of new drugs over the 30 years from 1981 to 2010","volume":"75","author":"Newman","year":"2012","journal-title":"J. Nat. Prod."},{"key":"ref_3","doi-asserted-by":"crossref","first-page":"17544","DOI":"10.1038\/s41598-021-96886-4","article-title":"Multiple strain analysis of Streptomyces species from Philippine marine sediments reveals intraspecies heterogeneity in antibiotic activities","volume":"11","author":"Tenebro","year":"2021","journal-title":"Sci. Rep."},{"key":"ref_4","doi-asserted-by":"crossref","first-page":"3086","DOI":"10.1128\/AEM.03859-14","article-title":"Red soils harbor diverse culturable actinomycetes that are promising sources of novel secondary metabolites","volume":"81","author":"Guo","year":"2015","journal-title":"Appl. Environ. Microbiol."},{"key":"ref_5","doi-asserted-by":"crossref","first-page":"2408","DOI":"10.3390\/microorganisms10122408","article-title":"Genomic investigation of desert Streptomyces huasconensis D23 reveals its environmental adaptability and antimicrobial activity","volume":"10","author":"Wen","year":"2022","journal-title":"Microorganisms"},{"key":"ref_6","doi-asserted-by":"crossref","first-page":"24","DOI":"10.1007\/s00203-022-03364-0","article-title":"Diversity of actinomycete and their metabolites isolated from Howz Soltan Lake, Iran","volume":"205","author":"Salehghamari","year":"2023","journal-title":"Arch. Microbiol."},{"key":"ref_7","doi-asserted-by":"crossref","first-page":"1012867","DOI":"10.3389\/fmicb.2022.1012867","article-title":"Isolation, antibacterial screening, and identification of bioactive cave dwelling bacteria in Fiji","volume":"13","author":"Pipite","year":"2022","journal-title":"Front. Microbiol."},{"key":"ref_8","doi-asserted-by":"crossref","first-page":"625","DOI":"10.1038\/nchembio.1890","article-title":"Minimum information about a biosynthetic gene cluster","volume":"11","author":"Medema","year":"2015","journal-title":"Nat. Chem. Biol."},{"key":"ref_9","doi-asserted-by":"crossref","first-page":"2727","DOI":"10.1002\/j.1460-2075.1989.tb08414.x","article-title":"Analysis of the nucleotide sequence of the Streptomyces glaucescens tcmI genes provides key information about the enzymology of polyketide antibiotic biosynthesis","volume":"8","author":"Bibb","year":"1989","journal-title":"EMBO J."},{"key":"ref_10","doi-asserted-by":"crossref","first-page":"856","DOI":"10.1016\/j.funbio.2018.04.011","article-title":"Diversity and evolution of polyketide biosynthesis gene clusters in the Ceratocystidaceae","volume":"122","author":"Sayari","year":"2018","journal-title":"Fungal. Biol."},{"key":"ref_11","doi-asserted-by":"crossref","first-page":"381","DOI":"10.7164\/antibiotics.51.381","article-title":"Alnumycin a new naphtoquinone antibiotic produced by an endophytic, Streptomyces sp.","volume":"51","author":"Bieber","year":"1998","journal-title":"J. Antibiot."},{"key":"ref_12","doi-asserted-by":"crossref","first-page":"545","DOI":"10.7164\/antibiotics.51.545","article-title":"K1115 A, a new anthraquinone that inhibits the binding of activator protein-1 (AP-1) to its recognition sites","volume":"51","author":"Naruse","year":"1998","journal-title":"J. Antibiot."},{"key":"ref_13","doi-asserted-by":"crossref","first-page":"401","DOI":"10.1007\/BF00280297","article-title":"Organisation and functions of the actVA region of the actinorhodin biosynthetic gene cluster of Streptomyces coelicolor","volume":"230","author":"Caballero","year":"1991","journal-title":"Mol. Genet. Genom."},{"key":"ref_14","doi-asserted-by":"crossref","first-page":"1633","DOI":"10.1099\/mic.0.26310-0","article-title":"Cloning, sequencing and heterologous expression of the medermycin biosynthetic gene cluster of Streptomyces sp. AM-7161: Towards comparative analysis of the benzoisochromanequinone gene clusters","volume":"149","author":"Ichinose","year":"2003","journal-title":"Microbiology"},{"key":"ref_15","doi-asserted-by":"crossref","first-page":"647","DOI":"10.1016\/S1074-5521(98)90292-7","article-title":"The granaticin biosynthetic gene cluster of Streptomyces violaceoruber T\u00fc22: Sequence analysis and expression in a heterologous host","volume":"5","author":"Ichinose","year":"1998","journal-title":"Chem. Biol."},{"key":"ref_16","doi-asserted-by":"crossref","first-page":"24854","DOI":"10.1016\/S0021-9258(17)31469-2","article-title":"DNA sequence and functions of the actVI region of the actinorhodin biosynthetic gene cluster of Streptomyces coelicolor A3(2)","volume":"269","author":"Caballero","year":"1994","journal-title":"J. Biol. Chem."},{"key":"ref_17","doi-asserted-by":"crossref","first-page":"19278","DOI":"10.1016\/S0021-9258(18)41772-3","article-title":"Nucleotide sequence and deduced functions of a set of cotranscribed genes of Streptomyces coelicolor A3(2) including the polyketide synthase for the antibiotic actinorhodin","volume":"267","author":"Boto","year":"1992","journal-title":"J. Biol. Chem."},{"key":"ref_18","doi-asserted-by":"crossref","first-page":"769","DOI":"10.1016\/0092-8674(91)90120-N","article-title":"The act cluster contains regulatory and antibiotic export genes, direct targets for translational control by the bldA tRNA gene of Streptomyces","volume":"66","author":"Caballero","year":"1991","journal-title":"Cell"},{"key":"ref_19","doi-asserted-by":"crossref","first-page":"1046","DOI":"10.1016\/j.chembiol.2008.07.022","article-title":"Characterization of the alnumycin gene cluster reveals unusual gene products for pyran ring formation and dioxan biosynthesis","volume":"15","author":"Oja","year":"2008","journal-title":"Chem. Biol."},{"key":"ref_20","doi-asserted-by":"crossref","first-page":"1291","DOI":"10.1073\/pnas.1207407110","article-title":"Structural basis for C-ribosylation in the alnumycin A biosynthetic pathway","volume":"110","author":"Oja","year":"2013","journal-title":"Proc. Natl. Acad. Sci. USA"},{"key":"ref_21","unstructured":"Bieber, B., and N\u00fcske, J. (1997). Alnumycin Useful as Antibiotic. (DE19745914A), German Patent Application."},{"key":"ref_22","doi-asserted-by":"crossref","first-page":"6046","DOI":"10.1128\/AAC.00991-15","article-title":"Effective antibiofilm polyketides against Staphylococcus aureus from the pyranonaphthoquinone biosynthetic pathways of Streptomyces species","volume":"59","author":"Oja","year":"2015","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_23","doi-asserted-by":"crossref","first-page":"2829","DOI":"10.1128\/JB.00228-12","article-title":"Characterization of the two-component monooxygenase system AlnT\/AlnH reveals early timing of quinone formation in alnumycin biosynthesis","volume":"194","author":"Grocholski","year":"2012","journal-title":"J. Bacteriol."},{"key":"ref_24","doi-asserted-by":"crossref","first-page":"533","DOI":"10.1080\/14786410600898961","article-title":"Anthraquinone derivatives from Micromonospora rhodorangea","volume":"23","author":"Xue","year":"2009","journal-title":"Nat. Prod. Res."},{"key":"ref_25","doi-asserted-by":"crossref","first-page":"1450","DOI":"10.1515\/znb-2006-1122","article-title":"New anthraquinones from a marine Streptomyces sp.\u2014Isolation, structure determination and biological activities","volume":"61","author":"Poumale","year":"2006","journal-title":"Z. Naturforsch."},{"key":"ref_26","doi-asserted-by":"crossref","first-page":"495","DOI":"10.1080\/10286020500172285","article-title":"Two new compounds from marine Streptomyces sp. FX-58","volume":"8","author":"Huang","year":"2006","journal-title":"J. Asian. Nat. Prod. Res."},{"key":"ref_27","doi-asserted-by":"crossref","first-page":"709826","DOI":"10.3389\/fmicb.2021.709826","article-title":"Anthraquinones as potential antibiofilm agents against methicillin-resistant Staphylococcus aureus","volume":"12","author":"Song","year":"2021","journal-title":"Front. Microbiol."},{"key":"ref_28","first-page":"583","article-title":"In vitro antibacterial properties of nalidixic acid, a new drug active against gram-negative organisms","volume":"161","author":"Deitz","year":"1963","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_29","doi-asserted-by":"crossref","first-page":"693","DOI":"10.1016\/0300-9084(84)90258-X","article-title":"The spacing of Escherichia coli DNA gyrase sites cleaved in vivo by treatment with oxolinic acid and sodium dodecyl sulfate","volume":"66","year":"1984","journal-title":"Biochemie"},{"key":"ref_30","doi-asserted-by":"crossref","first-page":"1994","DOI":"10.1128\/AAC.45.7.1994-2000.2001","article-title":"Interaction between DNA gyrase and quinolones: Effects of alanine mutations at GyrA subunit residues Ser83 and Asp87","volume":"45","author":"Barnard","year":"2001","journal-title":"Antimicrob. Agents Chemother."},{"key":"ref_31","doi-asserted-by":"crossref","first-page":"35927","DOI":"10.1074\/jbc.274.50.35927","article-title":"Quinolones inhibit DNA religation mediated by Staphylococcus aureus topoisomerase IV","volume":"274","author":"Anderson","year":"1999","journal-title":"J. Biol. Chem."},{"key":"ref_32","doi-asserted-by":"crossref","first-page":"627","DOI":"10.1006\/jmbi.1996.0274","article-title":"DNA gyrase and topoisomerase IV on the bacterial chromosome: Quinolone-induced DNA cleavage","volume":"258","author":"Chen","year":"1996","journal-title":"J. Mol. Biol."},{"key":"ref_33","doi-asserted-by":"crossref","first-page":"22615","DOI":"10.1074\/jbc.273.35.22615","article-title":"The DNA gyrase-quinolone complex","volume":"273","author":"Kampranis","year":"1998","journal-title":"J. Biol. Chem."},{"key":"ref_34","doi-asserted-by":"crossref","first-page":"1308","DOI":"10.3892\/etm.2014.1857","article-title":"Effect of emodin on the cariogenic properties of Streptococcus mutans and the development of caries in rats","volume":"8","author":"Xu","year":"2014","journal-title":"Exp. Ther. Med."},{"key":"ref_35","doi-asserted-by":"crossref","first-page":"3101","DOI":"10.3390\/molecules25133101","article-title":"The inhibitory activity of anthraquinones against pathogenic protozoa, bacteria, and fungi and the relationship to structure","volume":"25","author":"Friedman","year":"2020","journal-title":"Molecules"},{"key":"ref_36","doi-asserted-by":"crossref","first-page":"1595","DOI":"10.1016\/j.phytochem.2007.03.037","article-title":"Anthraquinones from the stem bark of Stereospermum zenkeri with antimicrobial activity","volume":"68","author":"Lenta","year":"2007","journal-title":"Phytochemistry"},{"key":"ref_37","doi-asserted-by":"crossref","first-page":"375","DOI":"10.1007\/s12562-011-0341-z","article-title":"Antibacterial properties of anthraquinones extracted from rhubarb against Aeromonas hydrophila","volume":"77","author":"Lu","year":"2011","journal-title":"Fish. Sci."},{"key":"ref_38","doi-asserted-by":"crossref","first-page":"2434","DOI":"10.3390\/microorganisms10122434","article-title":"An in-silico evaluation of anthraquinones as potential inhibitors of DNA gyrase B of Mycobacterium tuberculosis","volume":"10","author":"Amorim","year":"2022","journal-title":"Microorganisms"},{"key":"ref_39","doi-asserted-by":"crossref","first-page":"7699","DOI":"10.1007\/s00253-015-6657-3","article-title":"The direct anti-MRSA effect of emodin via damaging cell membrane","volume":"99","author":"Liu","year":"2015","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_40","doi-asserted-by":"crossref","first-page":"1041","DOI":"10.1016\/j.jep.2012.03.051","article-title":"Antioxidant, antimicrobial and antiverotoxic potentials of extracts of Curtisia dentata","volume":"141","author":"Doughari","year":"2012","journal-title":"J. Ethnopharmacol."},{"key":"ref_41","doi-asserted-by":"crossref","first-page":"117","DOI":"10.1016\/j.fsi.2020.04.024","article-title":"Rheum officinale extract promotes the innate immunity of orange-spotted grouper (Epinephelus coioides) and exerts strong bactericidal activity against six aquatic pathogens","volume":"102","author":"Kuo","year":"2020","journal-title":"Fish. Shellfish. Immunol."},{"key":"ref_42","doi-asserted-by":"crossref","first-page":"901","DOI":"10.1186\/s40064-016-2599-1","article-title":"Antibacterial activities and structure\u2013activity relationships of a panel of 48 compounds from Kenyan plants against multidrug resistant phenotypes","volume":"5","author":"Omosa","year":"2016","journal-title":"Springerplus"},{"key":"ref_43","doi-asserted-by":"crossref","first-page":"108","DOI":"10.1016\/j.jphotobiol.2010.09.009","article-title":"Antibacterial activity of anthraquinone derivatives from Heterophyllaea pustulata (Rubiaceae)","volume":"102","author":"Comini","year":"2011","journal-title":"J. Photochem. Photobiol. B"},{"key":"ref_44","doi-asserted-by":"crossref","first-page":"485","DOI":"10.1139\/cjpp-2014-0465","article-title":"Emodin is identified as the active component of ether extracts from Rhizoma Polygoni Cuspidati, for anti-MRSA activity","volume":"93","author":"Cao","year":"2015","journal-title":"Can. J. Physiol. Pharmacol."},{"key":"ref_45","doi-asserted-by":"crossref","first-page":"318","DOI":"10.1016\/j.bbrc.2017.10.033","article-title":"Comparative analysis of methicillin-sensitive and resistant Staphylococcus aureus exposed to emodin based on proteomic profiling","volume":"494","author":"Ji","year":"2017","journal-title":"Biochem. Biophys. Res. Commun."},{"key":"ref_46","doi-asserted-by":"crossref","first-page":"928","DOI":"10.1038\/202928a0","article-title":"Selection of media for isolation of streptomycetes","volume":"202","author":"Williams","year":"1964","journal-title":"Nature"},{"key":"ref_47","unstructured":"Kieser, T., Bibb, M., Buttner, M., Chater, K., and Hopwood, D. (1985). Practical Streptomyces Genetics, John Innes Foundation."},{"key":"ref_48","doi-asserted-by":"crossref","first-page":"722","DOI":"10.1101\/gr.215087.116","article-title":"Canu: Scalable and accurate long-read assembly via adaptive k-mer weighting and repeat separation","volume":"27","author":"Koren","year":"2017","journal-title":"Genome Res."},{"key":"ref_49","doi-asserted-by":"crossref","first-page":"312","DOI":"10.1016\/j.ygeno.2010.03.001","article-title":"Assembly algorithms for next-generation sequencing data","volume":"95","author":"Miller","year":"2010","journal-title":"Genomics"},{"key":"ref_50","doi-asserted-by":"crossref","unstructured":"Wick, R., Judd, L., Gorrie, C., and Holt, K. (2017). Unicycler: Resolving bacterial genome assemblies from short and long sequencing reads. PLoS Comput. Biol., 13.","DOI":"10.1371\/journal.pcbi.1005595"},{"key":"ref_51","doi-asserted-by":"crossref","first-page":"2182","DOI":"10.1038\/s41467-019-10210-3","article-title":"TYGS is an automated high-throughput platform for state-of-the-art genome-based taxonomy","volume":"10","year":"2019","journal-title":"Nat. Commun."},{"key":"ref_52","doi-asserted-by":"crossref","first-page":"D801","DOI":"10.1093\/nar\/gkab902","article-title":"TYGS and LPSN: A database tandem for fast and reliable genome-based classification and nomenclature of prokaryotes","volume":"50","author":"Carbasse","year":"2022","journal-title":"Nucleic Acids Res."},{"key":"ref_53","doi-asserted-by":"crossref","first-page":"339","DOI":"10.1093\/nar\/gkr466","article-title":"AntiSMASH: Rapid identification, annotation and analysis of secondary metabolite biosynthesis gene clusters in bacterial and fungal genome sequences","volume":"39","author":"Medema","year":"2011","journal-title":"Nucleic Acids Res."},{"key":"ref_54","doi-asserted-by":"crossref","first-page":"29","DOI":"10.1093\/nar\/gkab335","article-title":"AntiSMASH 6.0: Improving cluster detection and comparison capabilities","volume":"49","author":"Blin","year":"2021","journal-title":"Nucleic Acids Res."},{"key":"ref_55","doi-asserted-by":"crossref","first-page":"403","DOI":"10.1016\/S0022-2836(05)80360-2","article-title":"Basic local alignment search tool","volume":"215","author":"Altschul","year":"1990","journal-title":"J. Mol. Biol."},{"key":"ref_56","doi-asserted-by":"crossref","first-page":"293","DOI":"10.1128\/jb.62.3.293-300.1951","article-title":"Studies on lysogenesis. I. The mode of phage liberation by lysogenic Escherichia coli","volume":"62","author":"Bertani","year":"1951","journal-title":"J. Bacteriol."},{"key":"ref_57","unstructured":"(2009). Method for Dilution Antimicrobial Susceptibility Tests for Bacteria That Grow Aerobically. Standard No. CLSI M07-A8."},{"key":"ref_58","doi-asserted-by":"crossref","first-page":"139","DOI":"10.1016\/0378-1119(90)90148-K","article-title":"Cloning of the DNA gyrase genes under tac promoter control: Overproduction of the gyrase A and B proteins","volume":"93","author":"Hallett","year":"1990","journal-title":"Gene"},{"key":"ref_59","doi-asserted-by":"crossref","first-page":"60","DOI":"10.1186\/1471-2105-14-60","article-title":"Genome sequence-based species delimitation with confidence intervals and improved distance functions","volume":"14","author":"Auch","year":"2013","journal-title":"BMC Bioinform."},{"key":"ref_60","doi-asserted-by":"crossref","first-page":"1231","DOI":"10.1080\/00275514.1971.12019223","article-title":"Amino acids and growth factors in vitamin-free casamino acids","volume":"63","author":"Nolan","year":"1971","journal-title":"Mycologia"},{"key":"ref_61","doi-asserted-by":"crossref","first-page":"290","DOI":"10.1128\/am.24.2.290-291.1972","article-title":"Elemental analysis of vitamin-free casamino acids","volume":"24","author":"Nolan","year":"1972","journal-title":"Appl. Microbiol."},{"key":"ref_62","doi-asserted-by":"crossref","first-page":"52","DOI":"10.34297\/AJBSR.2019.04.000758","article-title":"Malt extract as a healthy substitute for refined sugar","volume":"4","year":"2019","journal-title":"Am. J. Biomed. Sci. Res."},{"key":"ref_63","doi-asserted-by":"crossref","first-page":"640","DOI":"10.1002\/bit.10608","article-title":"Toward consistent and productive complex media for industrial fermentations: Studies on yeast extract for a recombinant yeast fermentation process","volume":"82","author":"Zhang","year":"2003","journal-title":"Biotechnol. Bioeng."},{"key":"ref_64","doi-asserted-by":"crossref","first-page":"869","DOI":"10.1128\/jb.84.4.869-870.1962","article-title":"Minor element composition of yeast extract","volume":"84","author":"Grant","year":"1962","journal-title":"J. Bacteriol."},{"key":"ref_65","doi-asserted-by":"crossref","first-page":"557","DOI":"10.1007\/s11746-003-0737-6","article-title":"Variability in soy flour composition","volume":"80","author":"Porter","year":"2003","journal-title":"JAOCS"},{"key":"ref_66","first-page":"194","article-title":"Effects of peptone supplementation in different culture media on growth, metabolic pathway and productivity of CHO DG44 cells; a new insight into amino acid profiles","volume":"19","author":"Davami","year":"2015","journal-title":"Iran Biomed. J."},{"key":"ref_67","doi-asserted-by":"crossref","first-page":"181","DOI":"10.1016\/j.enzmictec.2007.01.004","article-title":"Enhance of anthraquinone production by effect of proline and aminoindan-2-phosphonic acid in Rubia tinctorum suspension cultures","volume":"41","author":"Perassolo","year":"2007","journal-title":"Enzyme Microb. Technol."},{"key":"ref_68","doi-asserted-by":"crossref","first-page":"1119","DOI":"10.1007\/s00253-007-1083-9","article-title":"pH shock induces overexpression of regulatory and biosynthetic genes for actinorhodin productionin Streptomyces coelicolor A3(2)","volume":"76","author":"Kim","year":"2007","journal-title":"Appl. Microbiol. Biotechnol."},{"key":"ref_69","first-page":"944","article-title":"Three new anthraquinone derivatives isolated from Symplocos racemosa and their antibiofilm activity","volume":"15","author":"Farooq","year":"2017","journal-title":"Chin. J. Nat. Med."},{"key":"ref_70","doi-asserted-by":"crossref","first-page":"107","DOI":"10.1016\/j.jbiotec.2008.10.013","article-title":"Ketosynthase III as a gateway to engineering the biosynthesis of antitumoral benastatin derivatives","volume":"140","author":"Xu","year":"2009","journal-title":"J. Biotechnol."},{"key":"ref_71","doi-asserted-by":"crossref","first-page":"14855","DOI":"10.1021\/bi0113723","article-title":"In vitro reconstitution and analysis of the chain initiating enzymes of the R1128 polyketide synthase","volume":"40","author":"Meadows","year":"2001","journal-title":"Biochemistry"},{"key":"ref_72","doi-asserted-by":"crossref","first-page":"9546","DOI":"10.1021\/bi049157k","article-title":"The acyltransferase homologue from the initiation module of the R1128 polyketide synthase is an acyl-ACP thioesterase that edits acetyl primer units","volume":"43","author":"Tang","year":"2004","journal-title":"Biochemistry"},{"key":"ref_73","doi-asserted-by":"crossref","first-page":"5917","DOI":"10.1016\/j.bmc.2004.08.026","article-title":"Remarkably different structures and reaction mechanisms of ketoreductases for the opposite stereochemical control in the biosynthesis of BIQ antibiotics","volume":"12","author":"Taguchi","year":"2004","journal-title":"Bioorg. Med. Chem."},{"key":"ref_74","doi-asserted-by":"crossref","first-page":"132501","DOI":"10.1016\/j.tet.2021.132501","article-title":"Recent total syntheses of anthraquinone-based natural products","volume":"105","author":"Gartman","year":"2022","journal-title":"Tetrahedron"},{"key":"ref_75","doi-asserted-by":"crossref","first-page":"498","DOI":"10.1016\/j.bmc.2010.11.001","article-title":"Synthesis and antibacterial activity study of a novel class of cationic anthraquinone analogs","volume":"19","author":"Zhang","year":"2011","journal-title":"Bioorg. Med. Chem."},{"key":"ref_76","doi-asserted-by":"crossref","first-page":"206","DOI":"10.1021\/acsinfecdis.6b00176","article-title":"Antimicrobial activity, AME resistance, and A-Site binding studies of anthraquinone\u2013neomycin conjugates","volume":"3","author":"Degtyareva","year":"2017","journal-title":"ACS Infect. Dis."},{"key":"ref_77","doi-asserted-by":"crossref","first-page":"2549","DOI":"10.1021\/jacs.9b12522","article-title":"Total synthesis and biological evaluation of tiancimycins A and B, yangpumicin A, and related anthraquinone-fused enediyne antitumor antibiotics","volume":"142","author":"Nicolaou","year":"2020","journal-title":"J. Am. Chem. Soc."}],"container-title":["Antibiotics"],"original-title":[],"language":"en","link":[{"URL":"https:\/\/www.mdpi.com\/2079-6382\/12\/7\/1116\/pdf","content-type":"unspecified","content-version":"vor","intended-application":"similarity-checking"}],"deposited":{"date-parts":[[2025,10,10]],"date-time":"2025-10-10T20:02:45Z","timestamp":1760126565000},"score":1,"resource":{"primary":{"URL":"https:\/\/www.mdpi.com\/2079-6382\/12\/7\/1116"}},"subtitle":[],"short-title":[],"issued":{"date-parts":[[2023,6,28]]},"references-count":77,"journal-issue":{"issue":"7","published-online":{"date-parts":[[2023,7]]}},"alternative-id":["antibiotics12071116"],"URL":"https:\/\/doi.org\/10.3390\/antibiotics12071116","relation":{},"ISSN":["2079-6382"],"issn-type":[{"value":"2079-6382","type":"electronic"}],"subject":[],"published":{"date-parts":[[2023,6,28]]}}}