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Tenebro CP, Trono DJVL, Balida LAP, Bayog LKA, Bruna JR, Sabido EM, Caspe DPC, de Los Santos ELC, Saludes JP, Dalisay DS. Synergy between Genome Mining, Metabolomics, and Bioinformatics Uncovers Antibacterial Chlorinated Carbazole Alkaloids and Their Biosynthetic Gene Cluster from Streptomyces tubbatahanensis sp. nov., a Novel Actinomycete Isolated from Sulu Sea, Philippines. Microbiol Spectr 2023; 11:e0366122. [PMID: 36809153 PMCID: PMC10100901 DOI: 10.1128/spectrum.03661-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2022] [Accepted: 01/30/2023] [Indexed: 02/23/2023] Open
Abstract
In this study, a novel actinomycete strain, DSD3025T, isolated from the underexplored marine sediments in Tubbataha Reefs Natural Park, Sulu Sea, Philippines, with the proposed name Streptomyces tubbatahanensis sp. nov., was described using polyphasic approaches and characterized using whole-genome sequencing. Its specialized metabolites were profiled using mass spectrometry and nuclear magnetic resonance analyses, followed by antibacterial, anticancer, and toxicity screening. The S. tubbatahanensis DSD3025T genome was comprised of 7.76 Mbp with a 72.3% G+C content. The average nucleotide identity and digital DNA-DNA hybridization values were 96.5% and 64.1%, respectively, compared with its closest related species, thus delineating the novelty of Streptomyces species. The genome encoded 29 putative biosynthetic gene clusters (BGCs), including a BGC region containing tryptophan halogenase and its associated flavin reductase, which were not found in its close Streptomyces relatives. The metabolite profiling unfolded six rare halogenated carbazole alkaloids, with chlocarbazomycin A as the major compound. A biosynthetic pathway for chlocarbazomycin A was proposed using genome mining, metabolomics, and bioinformatics platforms. Chlocarbazomycin A produced by S. tubbatahanensis DSD3025T has antibacterial activities against Staphylococcus aureus ATCC BAA-44 and Streptococcus pyogenes and showed antiproliferative activity against colon (HCT-116) and ovarian (A2780) human cancer cell lines. Chlocarbazomycin A exhibited no toxicity to liver cells but moderate and high toxicity to kidney and cardiac cell lines, respectively. IMPORTANCE Streptomyces tubbatahanensis DSD3025T is a novel actinomycete with antibiotic and anticancer activities from Tubbataha Reefs Natural Park, a United Nations Educational, Scientific and Cultural Organization World Heritage Site in Sulu Sea and considered one of the Philippines' oldest and most-well-protected marine ecosystems. In silico genome mining tools were used to identify putative BGCs that led to the discovery of genes involved in the production of halogenated carbazole alkaloids and new natural products. By integrating bioinformatics-driven genome mining and metabolomics, we unearthed the hidden biosynthetic richness and mined the associated chemical entities from the novel Streptomyces species. The bioprospecting of novel Streptomyces species from marine sediments of underexplored ecological niches serves as an important source of antibiotic and anticancer drug leads with unique chemical scaffolds.
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Affiliation(s)
- Chuckcris P. Tenebro
- Center for Chemical Biology and Biotechnology, University of San Agustin, Iloilo City, Philippines
| | - Dana Joanne V. L. Trono
- Center for Chemical Biology and Biotechnology, University of San Agustin, Iloilo City, Philippines
| | - Lex Aliko P. Balida
- Center for Chemical Biology and Biotechnology, University of San Agustin, Iloilo City, Philippines
| | - Leah Katrine A. Bayog
- Center for Chemical Biology and Biotechnology, University of San Agustin, Iloilo City, Philippines
| | - Julyanna R. Bruna
- Center for Chemical Biology and Biotechnology, University of San Agustin, Iloilo City, Philippines
| | - Edna M. Sabido
- Center for Chemical Biology and Biotechnology, University of San Agustin, Iloilo City, Philippines
| | - Dion Paul C. Caspe
- Center for Natural Drug Discovery and Development, University of San Agustin, Iloilo City, Philippines
| | - Emmanuel Lorenzo C. de Los Santos
- Research Analytics, Early Solutions Data & Translational Services, UCB Celltech, Slough, Berkshire, United Kingdom
- Balik Scientist Program, Department of Science and Technology, Philippine Council for Health Research and Development, Bicutan, Taguig City, Philippines
| | - Jonel P. Saludes
- Center for Natural Drug Discovery and Development, University of San Agustin, Iloilo City, Philippines
- Balik Scientist Program, Department of Science and Technology, Philippine Council for Health Research and Development, Bicutan, Taguig City, Philippines
- Department of Chemistry, College of Liberal Arts, Sciences, and Education, University of San Agustin, Iloilo City, Philippines
| | - Doralyn S. Dalisay
- Center for Chemical Biology and Biotechnology, University of San Agustin, Iloilo City, Philippines
- Balik Scientist Program, Department of Science and Technology, Philippine Council for Health Research and Development, Bicutan, Taguig City, Philippines
- Department of Biology, College of Liberal Arts, Sciences, and Education, University of San Agustin, Iloilo City, Philippines
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Shen Y, Zhang L, Yang M, Shi T, Li Y, Li L, Yu Y, Deng H, Lin HW, Zhou Y. Switching Prenyl Donor Specificities in Squalene Synthase-Like Aromatic Prenyltransferases from Bacterial Carbazole Alkaloid Biosynthesis. ACS Chem Biol 2023; 18:123-133. [PMID: 36608315 DOI: 10.1021/acschembio.2c00756] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023]
Abstract
Lavanduquinocin (LDQ) is a potent neuroprotective carbazole alkaloid from Streptomyces species that features a rare cyclic monoterpene/cyclolavandulyl moiety attached to the tricyclic carbazole nucleus. We elucidated the biosynthetic logic of LDQ by enzymatically reconstituting the total biosynthetic pathway and identified the genes required for generating the cyclolavandulyl moiety in LDQ based on mutagenetic analysis, including a cyclolavandulyl diphosphate synthase gene ldqA and a squalene synthase-like aromatic prenyltransferase gene ldqG. LdqG is homologous to carbazole prenyltransferases, NzsG and CqsB4, discovered from the biosynthetic pathways of two bacterial carbazoles, neocarazostatin and carquinostatin. Based on analysis of the sequences and modeled protein structures, further in vitro and in vivo site-directed mutagenetic analyses led to identification of two residue sites, F53 and C57 in NzsG vs I54 and A58 in LdqG, which play crucial roles in governing the prenyl donor specificities toward cyclolavandulyl, dimethylallyl, and geranyl diphosphates. By applying this knowledge in strain engineering, prenyl donor delivery was rationally switched to produce the desired prenylated carbazoles. The study provides an opportunity to rationally manipulate the prenylation modification to carbazole alkaloids, which could influence the biological activities by increasing the affinity for membranes as well as the interactions with cellular targets.
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Affiliation(s)
- Yaoyao Shen
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Liu Zhang
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Ming Yang
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Ting Shi
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yongzhen Li
- State Key Laboratory of Microbial Metabolism, Joint International Research Laboratory of Metabolic and Developmental Sciences, School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Lei Li
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Yi Yu
- Institute of TCM and Natural Products, Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education), School of Pharmaceutical Sciences, Wuhan University, Wuhan 430071, China
| | - Hai Deng
- Department of Chemistry, University of Aberdeen, Aberdeen AB24 3UE, U.K
| | - Hou-Wen Lin
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
| | - Yongjun Zhou
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University, Shanghai 200127, China
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Chemoenzymatic Synthesis of Indole-Containing Acyloin Derivatives. MOLECULES (BASEL, SWITZERLAND) 2023; 28:molecules28010354. [PMID: 36615552 PMCID: PMC9822442 DOI: 10.3390/molecules28010354] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 11/25/2022] [Revised: 12/28/2022] [Accepted: 12/29/2022] [Indexed: 01/04/2023]
Abstract
Indole-containing acyloins are either key intermediates of many antimicrobial/antiviral natural products or building blocks in the synthesis of biologically active molecules. As such, access to structurally diverse indole-containing acyloins has attracted considerable attention. In this report, we present a pilot study of using biotransformation to provide acyloins that contain various indole substituents. The biotransformation system contains the tryptophan synthase standalone β-subunit variant, PfTrpB6, generated from directed evolution in the literature; a commercially available L-amino acid oxidase (LAAO); and the thiamine-diphosphate (ThDP)-dependent enzyme NzsH, encoded in the biosynthetic gene cluster (nzs) of the bacterial carbazole alkaloid natural product named neocarazostatin A. The utilization of the first two enzymes, the PfTrpB variant and LAAO, is designed to provide structurally diverse indole 3-pyruvate derivatives as donor substrates for NzsH-catalysed biotransformation to provide acyloin derivatives. Our results demonstrate that NzsH displays a considerable substrate profile toward donor substrates for production of acyloins with different indole ring systems, suggesting that NzsH could be further explored as a potential biocatalyst via directed evolution to improve the catalytic efficiency in the future.
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Tang C, Wang W, Luo G, Song C, Bao Z, Li P, Hao G, Chi YR, Jin Z. Carbene‐Catalyzed Activation of C−Si Bonds for Chemo‐ and Enantioselective Cross Brook–Benzoin Reaction. Angew Chem Int Ed Engl 2022; 61:e202206961. [DOI: 10.1002/anie.202206961] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/12/2022] [Indexed: 01/06/2023]
Affiliation(s)
- Chenghao Tang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Guiyang 550025 China
- School of Life and Health Science Kaili University Kaili 556011 China
| | - Wei Wang
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Guiyang 550025 China
| | - Guoyong Luo
- School of Pharmacy Guizhou University of Traditional Chinese Medicine Guiyang 550025 China
| | - Chaoyang Song
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Guiyang 550025 China
| | - Zhaowei Bao
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Guiyang 550025 China
| | - Pei Li
- School of Life and Health Science Kaili University Kaili 556011 China
| | - Gefei Hao
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Guiyang 550025 China
| | - Yonggui Robin Chi
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Guiyang 550025 China
- Division of Chemistry & Biological Chemistry School of Physical & Mathematical Sciences Nanyang Technological University Singapore 637371 Singapore
| | - Zhichao Jin
- State Key Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Guizhou University Guiyang 550025 China
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Tang C, Wang W, Luo G, Song C, Bao Z, Li P, Hao G, Chi YR, Jin Z. Carbene‐Catalyzed Activation of C‐Si Bonds for Chemo‐ and Enantioselective Cross Brook‐Benzoin Reaction. Angew Chem Int Ed Engl 2022. [DOI: 10.1002/ange.202206961] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
| | - Wei Wang
- Guizhou University Chemistry CHINA
| | - Guoyong Luo
- Guizhou University Of Traditional Chinese Medicine Chemistry CHINA
| | | | | | - Pei Li
- Kaili University Chemistry CHINA
| | | | - Yonggui Robin Chi
- Nanyang Technological University Division of Chemistry and Biological Chemistry SINGAPORE
| | - Zhichao Jin
- Guizhou University Laboratory Breeding Base of Green Pesticide and Agricultural Bioengineering, Key Laboratory of Green Pesticide and Agricultural Bioengineering Ministry of Education Huaxi District 550025 Guiyang CHINA
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Cheng Y, Chen N, Li J, Su J, Yang J, Zhang C, Lin H, Zhou Y. Antimicrobial Chlorinated Carbazole Alkaloids from the
Sponge‐Associated
Actinomycete
Streptomyces diacarni
LHW51701. CHINESE J CHEM 2021. [DOI: 10.1002/cjoc.202000736] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Affiliation(s)
- Yijia Cheng
- School of Pharmaceutical Science Guangzhou University of Chinese Medicine Guangzhou Guangdong 510006 China
| | - Nannan Chen
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai 200127 China
| | - Jing Li
- College of Food Science and Technology, Shanghai Ocean University Shanghai 201306 China
| | - Jun‐Cheng Su
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai 200127 China
| | - Jingya Yang
- College of Food Science and Technology, Shanghai Ocean University Shanghai 201306 China
| | - Cui‐Xian Zhang
- School of Pharmaceutical Science Guangzhou University of Chinese Medicine Guangzhou Guangdong 510006 China
| | - Hou‐Wen Lin
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai 200127 China
| | - Yongjun Zhou
- Research Center for Marine Drugs, State Key Laboratory of Oncogenes and Related Genes, Department of Pharmacy, Ren Ji Hospital, School of Medicine, Shanghai Jiao Tong University Shanghai 200127 China
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Kim GS, Jang JP, Kwon M, Oh TH, Heo KT, Lee B, Lee JS, Ko SK, Hong YS, Ahn JS, Jang JH. Jejucarbazoles A–C, carbazole glycosides with indoleamine 2,3-dioxygenase 1 inhibitory activity from Streptomyces sp. KCB15JA151. RSC Adv 2021; 11:19805-19812. [PMID: 35479225 PMCID: PMC9033820 DOI: 10.1039/d1ra02895b] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/14/2021] [Accepted: 05/23/2021] [Indexed: 12/19/2022] Open
Abstract
A bioassay-guided investigation led to the isolation of three new carbazole glycosides, jejucarbazoles A–C (1–3), from Streptomyces sp. KCB15JA151. Their planar structures were elucidated by detailed NMR and MS spectroscopic analysis with a literature study. Their relative and absolute configurations were established by ROESY correlations, coupling constants, LC-MS analysis of thiocarbamoyl-thiazolidine carboxylate derivatives, and ECD calculation. Compounds 1–3 showed indoleamine 2,3-dioxygenase 1 (IDO1) inhibitory activity with IC50 values of 18.38, 9.17, and 8.81 μM. The molecular docking analysis suggested that all compounds act as heme-displacing inhibitors against IDO1 enzyme. This study presents the isolation and structure elucidation of jejucarbazoles A–C, isolated from Streptomyces sp. KCB15JA15 and their inhibitory effect and molecular docking analysis against the IDO1 enzyme.![]()
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Discovery of New Antibacterial Accramycins from a Genetic Variant of the Soil Bacterium, Streptomyces sp. MA37. Biomolecules 2020; 10:biom10101464. [PMID: 33092156 PMCID: PMC7590149 DOI: 10.3390/biom10101464] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/16/2020] [Revised: 10/12/2020] [Accepted: 10/18/2020] [Indexed: 12/29/2022] Open
Abstract
Continued mining of natural products from the strain Streptomyces sp. MA37 in our laboratory led to the discovery of a minor specialized metabolite (SM) called accramycin A. Owing to its low yield (0.2 mg/L) in the wild type strain, we investigated the roles of regulatory genes in the corresponding biosynthetic gene cluster (acc BGC) through gene inactivation with the aim of improving the titer of this compound. One of the resulting mutants (∆accJ) dramatically upregulated the production of accramycin A 1 by 330-fold (66 mg/L). Furthermore, ten new metabolites, accramycins B-K 2-11, were discovered, together with two known compounds, naphthacemycin B112 and fasamycin C 13 from the mutant extract. This suggested that accJ, annotated as multiple antibiotic resistance regulator (MarR), is a negative regulator gene in the accramycin biosynthesis. Compounds 1-13 inhibited the Gram-positive pathogens (Staphylococcus aureus, Enterococcus faecalis) and clinical isolates Enterococcus faecium (K59-68 and K60-39) and Staphylococcus haemolyticus with minimal inhibitory concentration (MIC) values in the range of 1.5-12.5 µg/mL. Remarkably, compounds 1-13 displayed superior activity against K60-39 (MIC = 3.1-6.3 µg/mL) compared to ampicillin (MIC = 25 µg/mL), and offered promising potential for the development of accramycin-based antibiotics that target multidrug-resistant Enterococcus clinical isolates. Our results highlight the importance of identifying the roles of regulatory genes in natural product discovery.
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Kobayashi M, Kuzuyama T. Recent Advances in the Biosynthesis of Carbazoles Produced by Actinomycetes. Biomolecules 2020; 10:biom10081147. [PMID: 32764478 PMCID: PMC7466098 DOI: 10.3390/biom10081147] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/04/2020] [Revised: 08/01/2020] [Accepted: 08/03/2020] [Indexed: 12/12/2022] Open
Abstract
Structurally diverse carbazole alkaloids are valuable due to their pharmaceutical properties and have been isolated from nature. Experimental knowledge on carbazole biosynthesis is limited. The latest development of in silico analysis of the biosynthetic gene clusters for bacterial carbazoles has allowed studies on the biosynthesis of a carbazole skeleton, which was established by sequential enzyme-coupling reactions associated with an unprecedented carbazole synthase, a thiamine-dependent enzyme, and a ketosynthase-like enzyme. This review describes the carbazole biosynthetic mechanism, which includes a key step in enzymatic formation of a tricyclic carbazole skeleton, followed by modifications such as prenylation and hydroxylation in the skeleton.
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Affiliation(s)
- Masaya Kobayashi
- Biotechnology Research Center, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan;
| | - Tomohisa Kuzuyama
- Graduate School of Agricultural and Life Sciences, The University of Tokyo, 1-1-1 Yayoi, Bunkyo-ku, Tokyo 113-8657, Japan
- Correspondence: ; Fax: +81-3-5841-3080
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A Co-Culturing Approach Enables Discovery and Biosynthesis of a Bioactive Indole Alkaloid Metabolite. Molecules 2020; 25:molecules25020256. [PMID: 31936318 PMCID: PMC7024260 DOI: 10.3390/molecules25020256] [Citation(s) in RCA: 30] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/29/2019] [Revised: 12/26/2019] [Accepted: 01/03/2020] [Indexed: 12/19/2022] Open
Abstract
Whole-genome sequence data of the genus Streptomyces have shown a far greater chemical diversity of metabolites than what have been discovered under typical laboratory fermentation conditions. In our previous natural product discovery efforts on Streptomyces sp. MA37, a bacterium isolated from the rhizosphere soil sample in Legon, Ghana, we discovered a handful of specialised metabolites from this talented strain. However, analysis of the draft genome of MA37 suggested that most of the encoded biosynthetic gene clusters (BGCs) remained cryptic or silent, and only a small fraction of BGCs for the production of specialised metabolites were expressed when cultured in our laboratory conditions. In order to induce the expression of the seemingly silent BGCs, we have carried out a co-culture experiment by growing the MA37 strain with the Gram-negative bacterium Pseudomonas sp. in a co-culture chamber that allows co-fermentation of two microorganisms with no direct contact but allows exchange of nutrients, metabolites, and other chemical cues. This co-culture approach led to the upregulation of several metabolites that were not previously observed in the monocultures of each strain. Moreover, the co-culture induced the expression of the cryptic indole alkaloid BGC in MA37 and led to the characterization of the known indolocarbazole alkaloid, BE-13793C 1. Neither bacterium produced compound 1 when cultured alone. The structure of 1 was elucidated by Nuclear Magnetic Resonance (NMR), mass spectrometry analyses and comparison of experimental with literature data. A putative biosynthetic pathway of 1 was proposed. Furthermore, BE-13793C 1 showed strong anti-proliferative activity against HT-29 (ATCC HTB-38) cells but no toxic effect to normal lung (ATCC CCL-171) cells. To the best of our knowledge, this is the first report for the activity of 1 against HT-29. No significant antimicrobial and anti-trypanosomal activities for 1 were observed. This research provides a solid foundation for the fact that a co-culture approach paves the way for increasing the chemical diversity of strain MA37. Further characterization of other upregulated metabolites in this strain is currently ongoing in our laboratory.
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