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Park J, Shin YH, Hwang S, Kim J, Moon DH, Kang I, Ko YJ, Chung B, Nam H, Kim S, Moon K, Oh KB, Cho JC, Lee SK, Oh DC. Discovery of Terminal Oxazole-Bearing Natural Products by a Targeted Metabologenomic Approach. Angew Chem Int Ed Engl 2024; 63:e202402465. [PMID: 38482567 DOI: 10.1002/anie.202402465] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2024] [Indexed: 04/13/2024]
Abstract
A targeted metabologenomic method was developed to selectively discover terminal oxazole-bearing natural products from bacteria. For this, genes encoding oxazole cyclase, a key enzyme in terminal oxazole biosynthesis, were chosen as the genomic signature to screen bacterial strains that may produce oxazole-bearing compounds. Sixteen strains were identified from the screening of a bacterial DNA library (1,000 strains) using oxazole cyclase gene-targeting polymerase chain reaction (PCR) primers. The PCR amplicon sequences were subjected to phylogenetic analysis and classified into nine clades. 1H-13C coupled-HSQC NMR spectra obtained from the culture extracts of the hit strains enabled the unequivocal detection of the target compounds, including five new oxazole compounds, based on the unique 1JCH values and chemical shifts of oxazole: lenzioxazole (1) possessing an unprecedented cyclopentane, permafroxazole (2) bearing a tetraene conjugated with carboxylic acid, tenebriazine (3) incorporating two modified amino acids, and methyl-oxazolomycins A and B (4 and 5). Tenebriazine displayed inhibitory activity against pathogenic fungi, whereas methyl-oxazolomycins A and B (4 and 5) selectively showed anti-proliferative activity against estrogen receptor-positive breast cancer cells. This metabologenomic method enables the logical and efficient discovery of new microbial natural products with a target structural motif without the need for isotopic labeling.
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Affiliation(s)
- Jiyoon Park
- Natural Products Research Institute, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Yern-Hyerk Shin
- Natural Products Research Institute, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Sunghoon Hwang
- Natural Products Research Institute, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jungwoo Kim
- Natural Products Research Institute, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Dong Hyun Moon
- Natural Products Research Institute, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Ilnam Kang
- Department of Biological Sciences, Inha University, 100 Inha-ro, Michuhol-gu, Incheon, 22212, Republic of Korea
| | - Yoon-Joo Ko
- Laboratory of Nuclear Magnetic Resonance, National Center for Inter-University Research Facilities (NCIRF), Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Beomkoo Chung
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences and Natural Products Research Institute, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Hyungsung Nam
- Department of Chemistry, College of Natural Sciences, and Natural Products Research Institute, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Seokhee Kim
- Department of Chemistry, College of Natural Sciences, and Natural Products Research Institute, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Kyuho Moon
- College of Pharmacy, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, Republic of Korea
| | - Ki-Bong Oh
- Department of Agricultural Biotechnology, College of Agriculture and Life Sciences and Natural Products Research Institute, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Jang-Cheon Cho
- Department of Biological Sciences, Inha University, 100 Inha-ro, Michuhol-gu, Incheon, 22212, Republic of Korea
| | - Sang Kook Lee
- Natural Products Research Institute, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
| | - Dong-Chan Oh
- Natural Products Research Institute, College of Pharmacy, Seoul National University, 1 Gwanak-ro, Gwanak-gu, Seoul, 08826, Republic of Korea
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2
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Li H, Li W, Song K, Liu Y, Zhao G, Du YL. Nitric oxide synthase-guided genome mining identifies a cytochrome P450 enzyme for olefin nitration in bacterial specialized metabolism. Synth Syst Biotechnol 2024; 9:127-133. [PMID: 38304063 PMCID: PMC10831120 DOI: 10.1016/j.synbio.2024.01.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/12/2023] [Revised: 01/08/2024] [Accepted: 01/09/2024] [Indexed: 02/03/2024] Open
Abstract
The biological signaling molecule nitric oxide (NO) has recently emerged as a metabolic precursor for the creation of microbial natural products with diversified structures and biological activities. Within the biosynthetic gene clusters (BGCs) of these compounds, genes associated with NO production pathways have been pinpointed. In this study, we employ a nitric oxide synthase (NOS)-guided genome mining strategy for the targeted discovery of NO-derived bacterial natural products and NO-utilizing biocatalysts. We show that a conserved NOS-containing BGC, distributed across several actinobacterial genomes, is responsible for the biosynthesis of lajollamycin, a unique nitro-tetraene-containing antibiotic whose biosynthetic mechanism remains elusive. Through a combination of in vivo and in vitro studies, we unveil the first cytochrome P450 enzyme capable of catalyzing olefin nitration in natural product biosynthesis. These results not only expand the current knowledge about biosynthetic nitration processes but also offer an efficient way for targeted identification of NO-utilizing metabolic pathways and novel nitrating biocatalysts.
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Affiliation(s)
- Hu Li
- Polytechnic Institute, Zhejiang University, Hangzhou, 310022, China
| | - Wei Li
- Department of Microbiology, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Kaihui Song
- Department of Microbiology, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Yu Liu
- College of Life Sciences, Zhejiang University, 310058, Hangzhou, China
| | - Guiyun Zhao
- Department of Microbiology, Zhejiang University School of Medicine, Hangzhou, 310058, China
| | - Yi-Ling Du
- Polytechnic Institute, Zhejiang University, Hangzhou, 310022, China
- Department of Microbiology, Zhejiang University School of Medicine, Hangzhou, 310058, China
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3
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Mannaa M, Han G, Jeong T, Kang M, Lee D, Jung H, Seo YS. Taxonomy-guided selection of Paraburkholderia busanensis sp. nov.: a versatile biocontrol agent with mycophagy against Colletotrichum scovillei causing pepper anthracnose. Microbiol Spectr 2023; 11:e0242623. [PMID: 37861313 PMCID: PMC10715207 DOI: 10.1128/spectrum.02426-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/09/2023] [Accepted: 09/04/2023] [Indexed: 10/21/2023] Open
Abstract
IMPORTANCE Traditional control methods for postharvest diseases rely on fungicides, which cause human health and environmental concerns. This study introduces a taxonomy-guided strategy for selecting biocontrol agents. By focusing on Paraburkholderia group, which harbors diverse plant-beneficial strains, the inadvertent selection of harmful strains was circumvented, thereby obviating the need for laborious in vitro screening assays. A highly promising candidate, strain P39, has been identified, exhibiting remarkable biocontrol activity against Colletotrichum scovillei. Through comprehensive genomic, physiological, and biochemical analyses, P39 was characterized as a novel species within the Paraburkholderia genus and designated Paraburkholderia busanensis. Moreover, these findings deepen our understanding of bacterial-fungal interactions, as they elucidate a potential pathway for the utilization of fungal chitin, thereby enhancing our understanding of bacterial mycophagy. P. busanensis is a promising source of antifungal volatiles and putative novel secondary metabolites.
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Affiliation(s)
- Mohamed Mannaa
- Department of Microbiology, Pusan National University, Busan, South Korea
- Department of Integrated Biological Science, Pusan National University, Busan, South Korea
- Department of Plant Pathology, Faculty of Agriculture, Cairo University, Giza, Egypt
| | - Gil Han
- Department of Microbiology, Pusan National University, Busan, South Korea
- Department of Integrated Biological Science, Pusan National University, Busan, South Korea
| | - Taeho Jeong
- Department of Microbiology, Pusan National University, Busan, South Korea
- Department of Integrated Biological Science, Pusan National University, Busan, South Korea
| | - Minhee Kang
- Department of Microbiology, Pusan National University, Busan, South Korea
- Department of Integrated Biological Science, Pusan National University, Busan, South Korea
| | - Duyoung Lee
- Department of Microbiology, Pusan National University, Busan, South Korea
- Department of Integrated Biological Science, Pusan National University, Busan, South Korea
| | - Hyejung Jung
- Department of Microbiology, Pusan National University, Busan, South Korea
- Department of Integrated Biological Science, Pusan National University, Busan, South Korea
| | - Young-Su Seo
- Department of Microbiology, Pusan National University, Busan, South Korea
- Department of Integrated Biological Science, Pusan National University, Busan, South Korea
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4
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Sulheim S, Fossheim FA, Wentzel A, Almaas E. Automatic reconstruction of metabolic pathways from identified biosynthetic gene clusters. BMC Bioinformatics 2021; 22:81. [PMID: 33622234 PMCID: PMC7901079 DOI: 10.1186/s12859-021-03985-0] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2020] [Accepted: 01/18/2021] [Indexed: 12/17/2022] Open
Abstract
Background A wide range of bioactive compounds is produced by enzymes and enzymatic complexes encoded in biosynthetic gene clusters (BGCs). These BGCs can be identified and functionally annotated based on their DNA sequence. Candidates for further research and development may be prioritized based on properties such as their functional annotation, (dis)similarity to known BGCs, and bioactivity assays. Production of the target compound in the native strain is often not achievable, rendering heterologous expression in an optimized host strain as a promising alternative. Genome-scale metabolic models are frequently used to guide strain development, but large-scale incorporation and testing of heterologous production of complex natural products in this framework is hampered by the amount of manual work required to translate annotated BGCs to metabolic pathways. To this end, we have developed a pipeline for an automated reconstruction of BGC associated metabolic pathways responsible for the synthesis of non-ribosomal peptides and polyketides, two of the dominant classes of bioactive compounds. Results The developed pipeline correctly predicts 72.8% of the metabolic reactions in a detailed evaluation of 8 different BGCs comprising 228 functional domains. By introducing the reconstructed pathways into a genome-scale metabolic model we demonstrate that this level of accuracy is sufficient to make reliable in silico predictions with respect to production rate and gene knockout targets. Furthermore, we apply the pipeline to a large BGC database and reconstruct 943 metabolic pathways. We identify 17 enzymatic reactions using high-throughput assessment of potential knockout targets for increasing the production of any of the associated compounds. However, the targets only provide a relative increase of up to 6% compared to wild-type production rates. Conclusion With this pipeline we pave the way for an extended use of genome-scale metabolic models in strain design of heterologous expression hosts. In this context, we identified generic knockout targets for the increased production of heterologous compounds. However, as the predicted increase is minor for any of the single-reaction knockout targets, these results indicate that more sophisticated strain-engineering strategies are necessary for the development of efficient BGC expression hosts.
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Affiliation(s)
- Snorre Sulheim
- Department of Biotechnology and Food Science, NTNU - Norwegian University of Science and Technology, Sem Sælands vei 8, 7034, Trondheim, Norway. .,Department of Biotechnology and Nanomedicine, SINTEF Industry, Richard Birkelands vei 3, 7034, Trondheim, Norway.
| | - Fredrik A Fossheim
- Department of Biotechnology and Food Science, NTNU - Norwegian University of Science and Technology, Sem Sælands vei 8, 7034, Trondheim, Norway
| | - Alexander Wentzel
- Department of Biotechnology and Nanomedicine, SINTEF Industry, Richard Birkelands vei 3, 7034, Trondheim, Norway
| | - Eivind Almaas
- Department of Biotechnology and Food Science, NTNU - Norwegian University of Science and Technology, Sem Sælands vei 8, 7034, Trondheim, Norway.,K.G. Jebsen Center for Genetic Epidemiology, NTNU - Norwegian University of Science and Technology, Håkon Jarls gate 11, 7030, Trondheim, Norway
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5
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Hou SY, Zhang MY, Wang HD, Zhang YX. Biosynthesis Gene Cluster and Oxazole Ring Formation Enzyme for Inthomycins in Streptomyces sp. Strain SYP-A7193. Appl Environ Microbiol 2020; 86:e01388-20. [PMID: 32801183 PMCID: PMC7531957 DOI: 10.1128/aem.01388-20] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2020] [Accepted: 08/08/2020] [Indexed: 11/20/2022] Open
Abstract
Inthomycins belong to a growing family of oxazole-containing polyketides and exhibit a broad spectrum of anti-oomycete and herbicidal activities. In this study, we purified inthomycins A and B from the metabolites of Streptomyces sp. strain SYP-A7193 and determined their chemical structures. Genome sequencing, comparative genomic analysis, and gene disruption of Streptomyces sp. SYP-A7193 showed that the inthomycin biosynthetic gene cluster (itm) belonged to the hybrid polyketide synthase (PKS)/nonribosomal peptide synthetase (NRPS) system. Functional domain comparison and disruption/complementation experiments of itm12 resulted in the complete loss of inthomycins A and B and the subsequent restoration of their production, confirming that itm12 encodes a discrete acyltransferase (AT), and hence, itm was considered to belong to the trans-AT type I PKS system. Moreover, the disruption/complementation experiments of itm15 also resulted in the loss and restoration of inthomycin A and B formation. Further gene cloning, expression, purification, and activity verification of itm15 revealed that Itm15 is a cyclodehydratase that catalyzes a straight-chain dehydration reaction to form an oxazole ring for the biosynthesis of inthomycins A and B. Thus, we discovered a novel enzyme that catalyzes oxazole ring formation and elucidated the complete biosynthetic pathway of inthomycins.IMPORTANCEStreptomyces species produce numerous secondary metabolites with diverse structures and pharmacological activities that are beneficial for human health and have several applications in agriculture. In this study, hybrid nonribosomal peptide synthetase/polyketide synthase metabolites inthomycins A and B were isolated from after fermenting Streptomyces sp. SYP-A7193. Genome sequencing, gene disruption, gene complementation, heterologous expression, and activity assay revealed that the biosynthesis gene assembly line of inthomycins A and B was a 95.3-kb trans-AT type I PKS system in the strain SYP-A7193. More importantly, Itm15, a cyclodehydratase, was identified to be an oxazole ring formation enzyme required for the biosynthesis of inthomycins A and B; it is significant to discover this catalyzation reaction in the PKS/NRPS system in the field of microbiology. Our findings could provide further insights into the diversity of trans-AT type I PKS systems and the mechanism of oxazole cyclization involved in the biosynthesis of natural products.
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Affiliation(s)
- Shao-Yang Hou
- School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, People's Republic of China
| | - Meng-Yue Zhang
- School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, People's Republic of China
| | - Hong-Da Wang
- School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, People's Republic of China
| | - Yi-Xuan Zhang
- School of Life Science and Biopharmaceutics, Shenyang Pharmaceutical University, Shenyang, People's Republic of China
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6
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Komaki H, Tamura T. Reclassification of Streptomyces hygroscopicus subsp. glebosus and Streptomyces libani subsp. rufus as later heterotypic synonyms of Streptomyces platensis. Int J Syst Evol Microbiol 2020; 70:4398-4405. [DOI: 10.1099/ijsem.0.004279] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/09/2023] Open
Abstract
We investigated the taxonomic relationships among
Streptomyces hygroscopicus
subsp.
glebosus
,
Streptomyces libani
subsp.
rufus
and
Streptomyces platensis
. The three species formed a single clade in the phylogenetic trees based on 16S rRNA gene sequence and multilocus sequence analyses. Digital DNA–DNA hybridization using whole genome sequences suggested that
S. hygroscopicus
subsp.
glebosus
,
S. libani
subsp.
rufus
and
S. platensis
belong to the same genomospecies. Previously reported phenotypic data also supported this synonymy. Therefore,
S. hygroscopicus
subsp.
glebosus
and
S. libani
subsp.
rufus
should be reclassified as later heterotypic synonyms of
S. platensis
.
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Affiliation(s)
- Hisayuki Komaki
- Biological Resource Center, National Institute of Technology and Evaluation (NBRC), Chiba 292-0818, Japan
| | - Tomohiko Tamura
- Biological Resource Center, National Institute of Technology and Evaluation (NBRC), Chiba 292-0818, Japan
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Song H, Rao C, Deng Z, Yu Y, Naismith JH. The Biosynthesis of the Benzoxazole in Nataxazole Proceeds via an Unstable Ester and has Synthetic Utility. Angew Chem Int Ed Engl 2020. [DOI: 10.1002/ange.201915685] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Affiliation(s)
- Haigang Song
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education)School of Pharmaceutical SciencesWuhan University 185 East Lake Road Wuhan 430071 P. R. China
- Division of Structural BiologyWellcome Centre for Human Genetics Roosevelt Drive Oxford OX3 7BN UK
- The Research Complex at Harwell Harwell Campus OX11 0FA UK
- The Rosalind Franklin Institute Harwell Campus OX11 0FA UK
| | - Cong Rao
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education)School of Pharmaceutical SciencesWuhan University 185 East Lake Road Wuhan 430071 P. R. China
| | - Zixin Deng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education)School of Pharmaceutical SciencesWuhan University 185 East Lake Road Wuhan 430071 P. R. China
| | - Yi Yu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education)School of Pharmaceutical SciencesWuhan University 185 East Lake Road Wuhan 430071 P. R. China
| | - James H. Naismith
- Division of Structural BiologyWellcome Centre for Human Genetics Roosevelt Drive Oxford OX3 7BN UK
- The Research Complex at Harwell Harwell Campus OX11 0FA UK
- The Rosalind Franklin Institute Harwell Campus OX11 0FA UK
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Antimicrobial biosynthetic potential and diversity of culturable soil actinobacteria from forest ecosystems of Northeast India. Sci Rep 2020; 10:4104. [PMID: 32139731 PMCID: PMC7057963 DOI: 10.1038/s41598-020-60968-6] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 02/06/2020] [Indexed: 02/07/2023] Open
Abstract
Actinobacteria is a goldmine for the discovery of abundant secondary metabolites with diverse biological activities. This study explores antimicrobial biosynthetic potential and diversity of actinobacteria from Pobitora Wildlife Sanctuary and Kaziranga National Park of Assam, India, lying in the Indo-Burma mega-biodiversity hotspot. A total of 107 actinobacteria were isolated, of which 77 exhibited significant antagonistic activity. 24 isolates tested positive for at least one of the polyketide synthase type I, polyketide synthase type II or non-ribosomal peptide synthase genes within their genome. Their secondary metabolite pathway products were predicted to be involved in the production of ansamycin, benzoisochromanequinone, streptogramin using DoBISCUIT database. Molecular identification indicated that these actinobacteria predominantly belonged to genus Streptomyces, followed by Nocardia and Kribbella. 4 strains, viz. Streptomyces sp. PB-79 (GenBank accession no. KU901725; 1313 bp), Streptomyces sp. Kz-28 (GenBank accession no. KY000534; 1378 bp), Streptomyces sp. Kz-32 (GenBank accession no. KY000536; 1377 bp) and Streptomyces sp. Kz-67 (GenBank accession no. KY000540; 1383 bp) showed ~89.5% similarity to the nearest type strain in EzTaxon database and may be considered novel. Streptomyces sp. Kz-24 (GenBank accession no. KY000533; 1367 bp) showed only 96.2% sequence similarity to S. malaysiensis and exhibited minimum inhibitory concentration of 0.024 µg/mL against methicilin resistant Staphylococcus aureus ATCC 43300 and Candida albicans MTCC 227. This study establishes that actinobacteria isolated from the poorly explored Indo-Burma mega-biodiversity hotspot may be an extremely rich reservoir for production of biologically active compounds for human welfare.
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Song H, Rao C, Deng Z, Yu Y, Naismith JH. The Biosynthesis of the Benzoxazole in Nataxazole Proceeds via an Unstable Ester and has Synthetic Utility. Angew Chem Int Ed Engl 2020; 59:6054-6061. [PMID: 31903677 PMCID: PMC7204872 DOI: 10.1002/anie.201915685] [Citation(s) in RCA: 21] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/08/2019] [Indexed: 11/25/2022]
Abstract
Heterocycles, a class of molecules that includes oxazoles, constitute one of the most common building blocks in current pharmaceuticals and are common in medicinally important natural products. The antitumor natural product nataxazole is a model for a large class of benzoxazole‐containing molecules that are made by a pathway that is not characterized. We report structural, biochemical, and chemical evidence that benzoxazole biosynthesis proceeds through an ester generated by an ATP‐dependent adenylating enzyme. The ester rearranges via a tetrahedral hemiorthoamide to yield an amide, which is a shunt product and not, as previously thought, an intermediate in the pathway. A second zinc‐dependent enzyme catalyzes the formation of hemiorthoamide from the ester but, by shuttling protons, the enzyme eliminates water, a reverse hydrolysis reaction, to yield the benzoxazole and avoids the amide. These insights have allowed us to harness the pathway to synthesize a series of novel halogenated benzoxazoles.
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Affiliation(s)
- Haigang Song
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education)School of Pharmaceutical SciencesWuhan University185 East Lake RoadWuhan430071P. R. China
- Division of Structural BiologyWellcome Centre for Human GeneticsRoosevelt DriveOxfordOX3 7BNUK
- The Research Complex at HarwellHarwell CampusOX11 0FAUK
- The Rosalind Franklin InstituteHarwell CampusOX11 0FAUK
| | - Cong Rao
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education)School of Pharmaceutical SciencesWuhan University185 East Lake RoadWuhan430071P. R. China
| | - Zixin Deng
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education)School of Pharmaceutical SciencesWuhan University185 East Lake RoadWuhan430071P. R. China
| | - Yi Yu
- Key Laboratory of Combinatorial Biosynthesis and Drug Discovery (Ministry of Education)School of Pharmaceutical SciencesWuhan University185 East Lake RoadWuhan430071P. R. China
| | - James H. Naismith
- Division of Structural BiologyWellcome Centre for Human GeneticsRoosevelt DriveOxfordOX3 7BNUK
- The Research Complex at HarwellHarwell CampusOX11 0FAUK
- The Rosalind Franklin InstituteHarwell CampusOX11 0FAUK
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10
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Oleksak P, Gonda J, Nepovimova E, Kuca K, Musilek K. The oxazolomycin family: a review of current knowledge. RSC Adv 2020; 10:40745-40794. [PMID: 35519217 PMCID: PMC9057759 DOI: 10.1039/d0ra08396h] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2020] [Accepted: 10/25/2020] [Indexed: 12/19/2022] Open
Abstract
Oxazolomycin A and neooxazolomycin were firstly isolated in 1985 by the group of Uemura et al. from the Streptomyces sp. bacteria.
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Affiliation(s)
- Patrik Oleksak
- University of Hradec Kralove
- Faculty of Science
- Department of Chemistry
- Hradec Kralove
- Czech Republic
| | - Jozef Gonda
- Pavol Jozef Safarik University
- Faculty of Science
- Department of Organic Chemistry
- Kosice
- Slovak Republic
| | - Eugenie Nepovimova
- University of Hradec Kralove
- Faculty of Science
- Department of Chemistry
- Hradec Kralove
- Czech Republic
| | - Kamil Kuca
- University of Hradec Kralove
- Faculty of Science
- Department of Chemistry
- Hradec Kralove
- Czech Republic
| | - Kamil Musilek
- University of Hradec Kralove
- Faculty of Science
- Department of Chemistry
- Hradec Kralove
- Czech Republic
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11
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Computational identification of co-evolving multi-gene modules in microbial biosynthetic gene clusters. Commun Biol 2019; 2:83. [PMID: 30854475 PMCID: PMC6395733 DOI: 10.1038/s42003-019-0333-6] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2018] [Accepted: 01/22/2019] [Indexed: 11/09/2022] Open
Abstract
The biosynthetic machinery responsible for the production of bacterial specialised metabolites is encoded by physically clustered group of genes called biosynthetic gene clusters (BGCs). The experimental characterisation of numerous BGCs has led to the elucidation of subclusters of genes within BGCs, jointly responsible for the same biosynthetic function in different genetic contexts. We developed an unsupervised statistical method able to successfully detect a large number of modules (putative functional subclusters) within an extensive set of predicted BGCs in a systematic and automated manner. Multiple already known subclusters were confirmed by our method, proving its efficiency and sensitivity. In addition, the resulting large collection of newly defined modules provides new insights into the prevalence and putative biosynthetic role of these modular genetic entities. The automated and unbiased identification of hundreds of co-evolving group of genes is an essential breakthrough for the discovery and biosynthetic engineering of high-value compounds.
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12
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Wang Q, Teng M, Li X. Functional and structural characterization of a novel catechol-O-methyltransferase from Schizosaccharomyces pombe. IUBMB Life 2018; 71:330-339. [PMID: 30501007 DOI: 10.1002/iub.1977] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2018] [Revised: 10/24/2018] [Accepted: 10/31/2018] [Indexed: 11/08/2022]
Abstract
Catechol-O-methyltransferase (COMT1 ) catalyzes the transfer of a methyl group from S-adenosylmethionine (SAM) to various catechol substrates. COMTs play vital roles in physiological processes in animals, plants, and fungi, as well as bacteria, and have essential application values in industry. spCOMT is a probable COMT from Schizosaccharomyces pombe. It has an extraordinary intracellular distribution different from other homologs and would thus be predicted to perform a distinct physiological function. In this report, recombinant spCOMT was purified and kinetically characterized for the first time. The enzymology assays indicate that spCOMT is a metal-dependent enzyme and belongs to class I OMTs. In addition, the crystal structures of apo-spCOMT and SAM-complexed spCOMT were also presented, revealing that spCOMT possesses a conserved SAM-binding site and Mg2+ pocket, but a distinct substrate pocket was not present in homologs. The mutagenesis ITC analysis revealed the SAM recognition characteristics of spCOMT. Based on all of the above findings, we speculated about the putative substrates' characteristics and the substrate recognition mechanisms of spCOMT. This work will help in elucidating the physiological functions of spCOMT in S. pombe. © 2018 IUBMB Life, 71(3):330-339, 2019.
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Affiliation(s)
- Qing Wang
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, People's Republic of China.,Key Laboratory of Structural Biology, Chinese Academy of Sciences, Hefei, Anhui, People's Republic of China
| | - Maikun Teng
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, People's Republic of China.,Key Laboratory of Structural Biology, Chinese Academy of Sciences, Hefei, Anhui, People's Republic of China
| | - Xu Li
- Hefei National Laboratory for Physical Sciences at Microscale, School of Life Sciences, University of Science and Technology of China, Hefei, Anhui, People's Republic of China.,Key Laboratory of Structural Biology, Chinese Academy of Sciences, Hefei, Anhui, People's Republic of China
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13
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Vander Wood DA, Keatinge-Clay AT. The modules of trans-acyltransferase assembly lines redefined with a central acyl carrier protein. Proteins 2018. [PMID: 29524261 DOI: 10.1002/prot.25493] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Here, the term "module" is redefined for trans-acyltransferase (trans-AT) assembly lines to agree with how its domains cooperate and evolutionarily co-migrate. The key domain in both the polyketide synthase (PKS) and nonribosomal peptide synthetase (NRPS) modules of assembly lines is the acyl carrier protein (ACP). ACPs not only relay growing acyl chains through the assembly line but also collaborate with enzymes in modules, both in cis and in trans, to add a specific chemical moiety. A ketosynthase (KS) downstream of ACP often plays the role of gatekeeper, ensuring that only a single intermediate generated by the enzymes of a module is passed downstream. Bioinformatic analysis of 526 ACPs from 33 characterized trans-AT assembly lines reveals ACPs from the same module type generally clade together, reflective of the co-evolution of these domains with their cognate enzymes. While KSs downstream of ACPs from the same module type generally also clade together, KSs upstream of ACPs do not-in disagreement with the traditional definition of a module. Beyond nomenclature, the presented analysis impacts our understanding of module function, the evolution of assembly lines, pathway prediction, and assembly line engineering.
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Affiliation(s)
- Drew A Vander Wood
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
| | - Adrian T Keatinge-Clay
- Department of Molecular Biosciences, The University of Texas at Austin, Austin, TX, 78712, USA
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14
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Harunari E, Komaki H, Igarashi Y. Biosynthetic origin of butyrolactol A, an antifungal polyketide produced by a marine-derived Streptomyces. Beilstein J Org Chem 2017; 13:441-450. [PMID: 28382182 PMCID: PMC5355916 DOI: 10.3762/bjoc.13.47] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2017] [Accepted: 02/20/2017] [Indexed: 11/23/2022] Open
Abstract
Butyrolactol A is an antifungal polyketide of Streptomyces bearing an uncommon tert-butyl starter unit and a polyol system in which eight hydroxy/acyloxy carbons are contiguously connected. Except for its congener butyrolactol B, there exist no structurally related natural products to date. In this study, inspired by our previous genomic analysis, incorporation of 13C- and 2H-labeled precursors into butyrolactol A was investigated. Based on the labeling pattern and sequencing analytical data, we confirmed that the tert-butyl group is derived from valine and its C-methylation with methionine and the polyol carbons are derived from a glycolysis intermediate, possibly hydroxymalonyl-ACP.
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Affiliation(s)
- Enjuro Harunari
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
| | - Hisayuki Komaki
- Biological Resource Center, National Institute of Technology and Evaluation (NBRC), 2-5-8 Kazusakamatari, Kisarazu, Chiba 292-0818, Japan
| | - Yasuhiro Igarashi
- Biotechnology Research Center and Department of Biotechnology, Toyama Prefectural University, 5180 Kurokawa, Imizu, Toyama 939-0398, Japan
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15
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Hemmerling F, Hahn F. Biosynthesis of oxygen and nitrogen-containing heterocycles in polyketides. Beilstein J Org Chem 2016; 12:1512-50. [PMID: 27559404 PMCID: PMC4979870 DOI: 10.3762/bjoc.12.148] [Citation(s) in RCA: 42] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/01/2016] [Accepted: 06/22/2016] [Indexed: 01/01/2023] Open
Abstract
This review highlights the biosynthesis of heterocycles in polyketide natural products with a focus on oxygen and nitrogen-containing heterocycles with ring sizes between 3 and 6 atoms. Heterocycles are abundant structural elements of natural products from all classes and they often contribute significantly to their biological activity. Progress in recent years has led to a much better understanding of their biosynthesis. In this context, plenty of novel enzymology has been discovered, suggesting that these pathways are an attractive target for future studies.
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Affiliation(s)
- Franziska Hemmerling
- Institut für Organische Chemie and Zentrum für Biomolekulare Wirkstoffe, Gottfried Wilhelm Leibniz Universität Hannover, Schneiderberg 38, 30167 Hannover, Germany; Fakultät für Biologie, Chemie und Geowissenschaften, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany
| | - Frank Hahn
- Institut für Organische Chemie and Zentrum für Biomolekulare Wirkstoffe, Gottfried Wilhelm Leibniz Universität Hannover, Schneiderberg 38, 30167 Hannover, Germany; Fakultät für Biologie, Chemie und Geowissenschaften, Universität Bayreuth, Universitätsstraße 30, 95440 Bayreuth, Germany
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16
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Helfrich EJN, Piel J. Biosynthesis of polyketides by trans-AT polyketide synthases. Nat Prod Rep 2016; 33:231-316. [DOI: 10.1039/c5np00125k] [Citation(s) in RCA: 230] [Impact Index Per Article: 28.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/18/2022]
Abstract
This review discusses the biosynthesis of natural products that are generated bytrans-AT polyketide synthases, a family of catalytically versatile enzymes that represents one of the major group of proteins involved in the production of bioactive polyketides.
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Affiliation(s)
- Eric J. N. Helfrich
- Institute of Microbiology
- Eidgenössische Technische Hochschule (ETH) Zurich
- 8093 Zurich
- Switzerland
| | - Jörn Piel
- Institute of Microbiology
- Eidgenössische Technische Hochschule (ETH) Zurich
- 8093 Zurich
- Switzerland
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17
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Jiang H, Wang YY, Guo YY, Shen JJ, Zhang XS, Luo HD, Ren NN, Jiang XH, Li YQ. An acyltransferase domain of FK506 polyketide synthase recognizing both an acyl carrier protein and coenzyme A as acyl donors to transfer allylmalonyl and ethylmalonyl units. FEBS J 2015; 282:2527-39. [PMID: 25865045 DOI: 10.1111/febs.13296] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/10/2015] [Revised: 04/07/2015] [Accepted: 04/08/2015] [Indexed: 11/30/2022]
Abstract
UNLABELLED Acyltransferase (AT) domains of polyketide synthases (PKSs) usually use coenzyme A (CoA) as an acyl donor to transfer common acyl units to acyl carrier protein (ACP) domains, initiating incorporation of acyl units into polyketides. Two clinical immunosuppressive agents, FK506 and FK520, are biosynthesized by the same PKSs in several Streptomyces strains. In this study, characterization of AT4FkbB (the AT domain of the fourth module of FK506 PKS) in transacylation reactions showed that AT4FkbB recognizes both an ACP domain (ACPT csA) and CoA as acyl donors for transfer of a unique allylmalonyl (AM) unit to an acyl acceptor ACP domain (ACP4FkbB), resulting in FK506 production. In addition, AT4FkbB uses CoA as an acyl donor to transfer an unusual ethylmalonyl (EM) unit to ACP4FkbB, resulting in FK520 production, and transfers AM units to non-native ACP acceptors. Characterization of AT4FkbB in self-acylation reactions suggests that AT4FkbB controls acyl unit specificity in transacylation reactions but not in self-acylation reactions. Generally, AT domains of PKSs only recognize one acyl donor; however, we report here that AT4FkbB recognizes two acyl donors for the transfer of different acyl units. DATABASE Nucleotide sequence data have been submitted to the GenBank database under accession numbers KJ000382 and KJ000383.
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Affiliation(s)
- Hui Jiang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.,Key Laboratory of Microbial Biochemistry and Metabolism Engineering of Zhejiang Province, Hangzhou, Zhejiang, China
| | - Yue-Yue Wang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yuan-Yang Guo
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Jie-Jie Shen
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xiao-Sheng Zhang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Hong-Dou Luo
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Ni-Ni Ren
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Xin-Hang Jiang
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China
| | - Yong-Quan Li
- College of Life Sciences, Zhejiang University, Hangzhou, Zhejiang, China.,Key Laboratory of Microbial Biochemistry and Metabolism Engineering of Zhejiang Province, Hangzhou, Zhejiang, China
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18
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Wang XJ, Zhang B, Yan YJ, An J, Zhang J, Liu CX, Xiang WS. Characterization and analysis of an industrial strain of Streptomyces bingchenggensis by genome sequencing and gene microarray. Genome 2014; 56:677-89. [PMID: 24299107 DOI: 10.1139/gen-2013-0098] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/14/2023]
Abstract
Streptomyces bingchenggensis is a soil bacterium that produces milbemycins, a family of macrolide antibiotics that are commercially important in crop protection and veterinary medicine. In addition, S. bingchenggensis produces many other natural products including the polyether nanchangmycin and novel cyclic pentapeptides. To identify the gene clusters involved in the biosynthesis of these compounds, and better clarify the biochemical pathways of these gene clusters, the whole genome of S. bingchenggensis was sequenced, and the transcriptome profile was subsequently investigated by microarray. In comparison with other sequenced genomes in Streptomyces, S. bingchenggensis has the largest linear chromosome consisting of 11 936 683 base pairs (bp), with an average GC content of 70.8%. The 10 023 predicted protein-coding sequences include at least 47 gene clusters correlated with the biosynthesis of known or predicted secondary metabolites. Transcriptional analysis demonstrated an extremely high expression level of the milbemycin gene cluster during the entire growth period and a moderately high expression level of the nanchangmycin gene cluster during the initial hours that subsequently decreased. However, other gene clusters appear to be silent. The genome-wide analysis of the secondary metabolite gene clusters in S. bingchenggensis, coupled with transcriptional analysis, will facilitate the rational development of high milbemycins-producing strains as well as the discovery of new natural products.
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Affiliation(s)
- Xiang-Jing Wang
- a School of Life Science, Northeast Agricultural University, Harbin 150030, China
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19
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Identification of the incednine biosynthetic gene cluster: characterization of novel β-glutamate-β-decarboxylase IdnL3. J Antibiot (Tokyo) 2013; 66:691-9. [DOI: 10.1038/ja.2013.76] [Citation(s) in RCA: 33] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2013] [Revised: 06/11/2013] [Accepted: 06/21/2013] [Indexed: 12/18/2022]
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20
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Du YL, Dalisay DS, Andersen RJ, Ryan KS. N-carbamoylation of 2,4-diaminobutyrate reroutes the outcome in padanamide biosynthesis. ACTA ACUST UNITED AC 2013; 20:1002-11. [PMID: 23911586 DOI: 10.1016/j.chembiol.2013.06.013] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2013] [Revised: 06/05/2013] [Accepted: 06/25/2013] [Indexed: 01/07/2023]
Abstract
Padanamides are linear tetrapeptides notable for the absence of proteinogenic amino acids in their structures. In particular, two unusual heterocycles, (S)-3-amino-2-oxopyrrolidine-1-carboxamide (S-Aopc) and (S)-3-aminopiperidine-2,6-dione (S-Apd), are found at the C-termini of padanamides A and B, respectively. Here we identify the padanamide biosynthetic gene cluster and carry out systematic gene inactivation studies. Our results show that padanamides are synthesized by highly dissociated hybrid nonribosomal peptide synthetase/polyketide synthase machinery. We further demonstrate that carbamoyltransferase gene padQ is critical to the formation of padanamide A but dispensable for biosynthesis of padanamide B. Biochemical investigations show that PadQ carbamoylates the rare biosynthetic precursor l-2,4-diaminobutyrate, generating l-2-amino-4-ureidobutyrate, the presumed precursor to the C-terminal residue of padanamide A. By contrast, the C-terminal residue of padanamide B may derive from glutamine. An unusual thioesterase-catalyzed cyclization is proposed to generate the S-Aopc/S-Apd heterocycles.
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Affiliation(s)
- Yi-Ling Du
- Department of Chemistry, University of British Columbia, Vancouver, BC V6T 1Z1, Canada
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21
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Angelov P, Chau YKS, Fryer PJ, Moloney MG, Thompson AL, Trippier PC. Biomimetic synthesis, antibacterial activity and structure-activity properties of the pyroglutamate core of oxazolomycin. Org Biomol Chem 2012; 10:3472-85. [PMID: 22437843 DOI: 10.1039/c2ob00042c] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/03/2023]
Abstract
Biomimetic intramolecular aldol reactions on oxazolidine templates derived from serine may be used to generate densely functionalised pyroglutamates, which are simpler mimics of the right hand side of oxazolomycin. Some of the compounds from this sequence exhibit in vivo activity against S. aureus and E. coli, suggesting that pyroglutamate scaffolds may be useful templates for the development of novel antibacterials, and cheminformatic analysis has been used to provide some structure-activity data.
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Affiliation(s)
- Plamen Angelov
- Department of Chemistry, Chemistry Research Laboratory, The University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, UK
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22
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Musiol EM, Weber T. Discrete acyltransferases involved in polyketide biosynthesis. MEDCHEMCOMM 2012. [DOI: 10.1039/c2md20048a] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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23
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Kang Q, Bai L, Deng Z. Toward steadfast growth of antibiotic research in China: from natural products to engineered biosynthesis. Biotechnol Adv 2011; 30:1228-41. [PMID: 21930196 DOI: 10.1016/j.biotechadv.2011.09.001] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/01/2011] [Revised: 09/04/2011] [Accepted: 09/05/2011] [Indexed: 11/30/2022]
Abstract
Antibiotics are widely used for clinical treatment and preventing or curing diseases in agriculture. Cloning and studies of their biosynthetic gene clusters are vital for yield enhancement and engineering new derivatives with new and prominent activities. In recent years, research in this aspect is impressively active in China. This article reviews biosynthetic progress on 28 antibiotics, including polyketides, nonribosomal peptides, hybrid polyketide-nonribosomal peptides, peptidyl nucleoside, nucleoside, and others. Their biosynthetic mechanisms were disclosed, and their derivatives with new structures/activities were obtained by gene inactivation, mutasynthesis and combinatorial biosynthesis.
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Affiliation(s)
- Qianjin Kang
- State key Laboratory of Microbial Metabolism and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
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24
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Gulder TAM, Freeman MF, Piel J. The Catalytic Diversity of Multimodular Polyketide Synthases: Natural Product Biosynthesis Beyond Textbook Assembly Rules. Top Curr Chem (Cham) 2011. [PMID: 21360321 DOI: 10.1007/128_2010_113] [Citation(s) in RCA: 23] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
Bacterial multimodular polyketide synthases (PKSs) are responsible for the biosynthesis of a wide range of pharmacologically active natural products. These megaenzymes contain numerous catalytic and structural domains and act as biochemical templates to generate complex polyketides in an assembly line-like fashion. While the prototypical PKS is composed of only a few different domain types that are fused together in a combinatorial fashion, an increasing number of enzymes is being found that contain additional components. These domains can introduce remarkably diverse modifications into polyketides. This review discusses our current understanding of such noncanonical domains and their role in expanding the biosynthetic versatility of bacterial PKSs.
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25
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Karki S, Kwon SY, Yoo HG, Suh JW, Park SH, Kwon HJ. The methoxymalonyl-acyl carrier protein biosynthesis locus and the nearby gene with the beta-ketoacyl synthase domain are involved in the biosynthesis of galbonolides in Streptomyces galbus, but these loci are separate from the modular polyketide synthase gene cluster. FEMS Microbiol Lett 2010; 310:69-75. [PMID: 20662933 DOI: 10.1111/j.1574-6968.2010.02048.x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022] Open
Abstract
Galbonolides A and B are antifungal compounds, which are produced by Streptomyces galbus. A multimodular polyketide synthase (PKS) was predicted to catalyze their biosynthesis, and a methoxymalonyl-acyl carrier protein (methoxymalonyl-ACP) was expected to be involved in the biosynthesis of galbonolide A. Cloning of a methoxymalonyl-ACP biosynthesis locus (galGHIJK) and the flanking regions has revealed that the locus is colocalized with beta-ketoacyl synthase (KAS)-related genes (orf3, 4, and 5), but separated from any multimodular PKS gene cluster in S. galbus. A galI-disruption mutant (SK-galI-5) is unable to produce galbonolide A, but can synthesize galbonolide B, indicating that galGHIJK is involved in the biosynthesis of galbonolide A. A disruption mutant of orf4 is severely impaired in the production of both galbonolides A and B. These results indicate that galGHIJK and the KAS genes are involved in the biosynthesis of galbonolides, although they are not colocalized with a multimodular PKS gene cluster. We further propose that a single galbonolide PKS generates two discrete structures, galbonolides A and B, by alternatively incorporating methoxymalonate and methylmalonate, respectively.
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Affiliation(s)
- Suman Karki
- Department of Biological Science, Division of Bioscience and Bioinformatics, Myongji University, San 38-2 Nam-dong, Yongin-si, Gyunggi-do, Korea
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26
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Abstract
This review discusses the biosynthesis of natural products that are generated by trans-AT polyketide synthases, a family of catalytically versatile enzymes that have recently been recognized as one of the major group of proteins involved in the production of bioactive polyketides. 436 references are cited.
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Affiliation(s)
- Jörn Piel
- Kekulé Institute of Organic Chemistry and Biochemistry, University of Bonn, Bonn, Germany.
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27
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Zhao C, Coughlin JM, Ju J, Zhu D, Wendt-Pienkowski E, Zhou X, Wang Z, Shen B, Deng Z. Oxazolomycin biosynthesis in Streptomyces albus JA3453 featuring an "acyltransferase-less" type I polyketide synthase that incorporates two distinct extender units. J Biol Chem 2010; 285:20097-108. [PMID: 20406823 DOI: 10.1074/jbc.m109.090092] [Citation(s) in RCA: 65] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The oxazolomycins (OZMs) are a growing family of antibiotics produced by several Streptomyces species that show diverse and important antibacterial, antitumor, and anti-human immunodeficiency virus activity. Oxazolomycin A is a peptide-polyketide hybrid compound containing a unique spiro-linked beta-lactone/gamma-lactam, a 5-substituted oxazole ring. The oxazolomycin biosynthetic gene cluster (ozm) was identified from Streptomyces albus JA3453 and localized to 79.5-kb DNA, consisting of 20 open reading frames that encode non-ribosomal peptide synthases, polyketide synthases (PKSs), hybrid non-ribosomal peptide synthase-PKS, trans-acyltransferases (trans-ATs), enzymes for methoxymalonyl-acyl carrier protein (ACP) synthesis, putative resistance genes, and hypothetical regulation genes. In contrast to classical type I polyketide or fatty acid biosynthases, all 10 PKS modules in the gene cluster lack cognate ATs. Instead, discrete ATs OzmM (with tandem domains OzmM-AT1 and OzmM-AT2) and OzmC were equipped to carry out all of the loading functions of both malonyl-CoA and methoxymalonyl-ACP extender units. Strikingly, only OzmM-AT2 is required for OzmM activity for OZM biosynthesis, whereas OzmM-AT1 seemed to be a cryptic AT domain. The above findings, together with previous results using isotope-labeled precursor feeding assays, are assembled for the OZM biosynthesis model to be proposed. The incorporation of both malonyl-CoA (by OzmM-AT2) and methoxymalonyl-ACP (by OzmC) extender units seemed to be unprecedented for this class of trans-AT type I PKSs, which might be fruitfully manipulated to create structurally diverse novel compounds.
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Affiliation(s)
- Chunhua Zhao
- Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiaotong University, Shanghai 200030, China
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28
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Bagwell CL, Moloney MG, Yaqoob M. Oxazolomycins: Natural product lead structures for novel antibacterials by click fragment conjugation. Bioorg Med Chem Lett 2010; 20:2090-4. [DOI: 10.1016/j.bmcl.2010.02.066] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2010] [Revised: 02/17/2010] [Accepted: 02/17/2010] [Indexed: 12/25/2022]
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29
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Cloning of separate meilingmycin biosynthesis gene clusters by use of acyltransferase-ketoreductase didomain PCR amplification. Appl Environ Microbiol 2010; 76:3283-92. [PMID: 20348291 DOI: 10.1128/aem.02262-09] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Five meilingmycins, A to E, with A as the major component, were isolated from Streptomyces nanchangensis NS3226. Through nuclear magnetic resonance (NMR) characterization, meilingmycins A to E proved to be identical to reported milbemycins alpha11, alpha13, alpha14, beta1, and beta9, respectively. Sequencing of a previously cloned 103-kb region identified three modular type I polyketide synthase genes putatively encoding the last 11 elongation steps, three modification proteins, and one transcriptional regulatory protein for meilingmycin biosynthesis. However, the expected loading module and the first two elongation modules were missing. In meilingmycin, the presence of a methyl group at C-24 and a hydroxyl group at C-25 suggests that the elongation module 1 contains a methylmalonyl-coenzyme A (CoA)-specific acyltransferase (ATp) domain and a ketoreductase (KR) domain. Based on the conserved motifs of the ATp and KR domains, a pair of primers was designed for PCR amplification, and a 1.40-kb expected fragment was amplified, whose sequence shows significant homology with the elongation module 1 of the aveA1-encoded enzyme AVES1. A polyketide synthase (PKS) gene encoding one loading and two elongation modules, with a downstream C-5-O-methyltransferase gene, meiD, was subsequently localized 55 kb apart from the previously sequenced region, and its deletion abolishes meilingmycin production. A series of deletions within the 55-kb intercluster region rules out its involvement in meilingmycin biosynthesis. Furthermore, gene deletion of meiD eliminates meilingmycins D and E, with methyls at C-5. Our work provides a more specific strategy for the cloning of modular type I PKS gene clusters. The cloning of the meilingmycin gene clusters paves the way for its pathway engineering.
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30
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Cheng YQ, Coughlin JM, Lim SK, Shen B. Type I polyketide synthases that require discrete acyltransferases. Methods Enzymol 2009; 459:165-86. [PMID: 19362640 DOI: 10.1016/s0076-6879(09)04608-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/22/2023]
Abstract
The diverse structures of polyketide natural products are reflected by the equally diverse polyketide biosynthetic enzymes, namely polyketide synthases (PKSs). Three major classes of PKSs are known-noniterative type I PKSs, iterative type II PKSs and acyl carrier protein-independent type III PKSs, each of which consists of additional variants. One such variant is the noniterative type I PKS in which each PKS module lacks the cognate acyltransferase (AT) domain. The essential AT activity is instead provided by a discrete AT in trans. Termed "AT-less" type I PKSs, the loading of the malonate extender units by the discrete AT enzyme LnmG to each of the AT-less PKS modules of LnmI and LnmJ was confirmed experimentally for biosynthesis of the anticancer antibiotic leinamycin (LNM). The LNM PKS has since served as a model for the continuous discovery of numerous additional AT-less type I PKSs incorporating variable extender units. However, biochemical characterization of AT-less type I PKSs remains very limited, and the mechanism by which AT-less type I PKSs accommodate multiple extender units is unknown. This chapter provides the protocols used to establish and characterize the LNM PKS. Application of these methods to other AT-less type I PKSs should aid the biochemical characterization and hence possible exploitation of these unique PKSs for polyketide natural product structural diversity by combinatorial biosynthetic methods.
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Affiliation(s)
- Yi-Qiang Cheng
- Department of Chemistry and Biochemistry, University of Wisconsin-Milwaukee, Milwaukee, Wisconsin, USA
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31
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Olano C, Méndez C, Salas JA. Antitumor compounds from marine actinomycetes. Mar Drugs 2009; 7:210-48. [PMID: 19597582 PMCID: PMC2707044 DOI: 10.3390/md7020210] [Citation(s) in RCA: 215] [Impact Index Per Article: 14.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2009] [Revised: 06/08/2009] [Accepted: 06/11/2009] [Indexed: 11/16/2022] Open
Abstract
Chemotherapy is one of the main treatments used to combat cancer. A great number of antitumor compounds are natural products or their derivatives, mainly produced by microorganisms. In particular, actinomycetes are the producers of a large number of natural products with different biological activities, including antitumor properties. These antitumor compounds belong to several structural classes such as anthracyclines, enediynes, indolocarbazoles, isoprenoides, macrolides, non-ribosomal peptides and others, and they exert antitumor activity by inducing apoptosis through DNA cleavage mediated by topoisomerase I or II inhibition, mitochondria permeabilization, inhibition of key enzymes involved in signal transduction like proteases, or cellular metabolism and in some cases by inhibiting tumor-induced angiogenesis. Marine organisms have attracted special attention in the last years for their ability to produce interesting pharmacological lead compounds.
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Affiliation(s)
- Carlos Olano
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, 33006 Oviedo, Spain; E-Mails:
(C.O.);
(C.M.)
| | - Carmen Méndez
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, 33006 Oviedo, Spain; E-Mails:
(C.O.);
(C.M.)
| | - José A. Salas
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (I.U.O.P.A), Universidad de Oviedo, 33006 Oviedo, Spain; E-Mails:
(C.O.);
(C.M.)
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32
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McAlpine JB. Advances in the understanding and use of the genomic base of microbial secondary metabolite biosynthesis for the discovery of new natural products. JOURNAL OF NATURAL PRODUCTS 2009; 72:566-572. [PMID: 19199817 DOI: 10.1021/np800742z] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Over the past decade major changes have occurred in the access to genome sequences that encode the enzymes responsible for the biosynthesis of secondary metabolites, knowledge of how those sequences translate into the final structure of the metabolite, and the ability to alter the sequence to obtain predicted products via both homologous and heterologous expression. Novel genera have been discovered leading to new chemotypes, but more surprisingly several instances have been uncovered where the apparently general rules of modular translation have not applied. Several new biosynthetic pathways have been unearthed, and our general knowledge grows rapidly. This review aims to highlight some of the more striking discoveries and advances of the decade.
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Affiliation(s)
- James B McAlpine
- Thallion Pharmaceuticals Inc., 7150 Alexander-Fleming, Montreal H4S 2C8, Canada.
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Abstract
This review covers the biosynthesis of extender units that are utilized for the assembly of polyketides by polyketide synthases. The metabolic origins of each of the currently known polyketide synthase extender units are covered.
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Affiliation(s)
- Yolande A. Chan
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, WI 53706, USA
| | - Angela M. Podevels
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Brian M. Kevany
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
| | - Michael G. Thomas
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI 53706, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, WI 53706, USA
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Selective removal of aberrant extender units by a type II thioesterase for efficient FR-008/candicidin biosynthesis in Streptomyces sp. strain FR-008. Appl Environ Microbiol 2008; 74:7235-42. [PMID: 18836004 DOI: 10.1128/aem.01012-08] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Gene fscTE, encoding a putative type II thioesterase (TEII), was associated with the FR-008/candicidin gene cluster. Deletion of fscTE reduced approximately 90% of the FR-008/candicidin production, while the production level was well restored when fscTE was added back to the mutant in trans. FscTE was unable to compensate for the release of the maturely elongated polyketide as site-directed inactivation of the type I thioesterase (TEI) totally abolished FR-008/candicidin production. Direct biochemical analysis of FscTE in parallel with its homologue TylO from the tylosin biosynthetic pathway demonstrated their remarkable preferences for acyl-thioesters (i.e., propionyl-S-N-acetylcysteamine [SNAC] over methylmalonyl-SNAC and acetyl-SNAC over malonyl-SNAC) and thus concluded that TEII could maintain effective polyketide biosynthesis by selectively removing the nonelongatable residues bound to acyl carrier proteins. Overexpression of FscTE under the strong constitutive ermE*p promoter in the wild-type strain did not suppress FR-008/candicidin formation, which confirmed its substrate specificity in vivo. Furthermore, successful complementation of the fscTE mutant was obtained with fscTE and tylO, whereas no complementation was detected with nonribosomal peptide synthetase (NRPS) TEII tycF and srfAD, reflecting substrate specificities of TEIIs distinctive from those of either polyketide synthases or NRPSs.
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35
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On the antibiotic activity of oxazolomycin. Bioorg Med Chem Lett 2008; 18:4081-6. [PMID: 18558487 DOI: 10.1016/j.bmcl.2008.05.105] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/22/2008] [Revised: 05/23/2008] [Accepted: 05/24/2008] [Indexed: 11/24/2022]
Abstract
Structural analysis of oxazolomycin and simpler fragments containing a common 3-hydroxy-2,2-dimethylpropanamide moiety has indicated that a U-shaped conformation is preferred, in some cases stabilised by hydrogen bonding between the N-H and O-H residues, as shown by a combination of molecular modelling, NMR spectroscopic and single crystal X-ray analysis. A direct synthesis of this unit has been established via the opening of beta-lactones by a range of amines, and their antibacterial activity been shown to vary with the hydrophobic character of the substituents.
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36
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Song D, Coughlin J, Ju J, Zhou X, Shen B, Zhao C, Deng Z. Alternative method for site-directed mutagenesis of complex polyketide synthase in Streptomyces albus JA3453. Acta Biochim Biophys Sin (Shanghai) 2008; 40:319-26. [PMID: 18401530 DOI: 10.1111/j.1745-7270.2008.00408.x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022] Open
Abstract
Sequence analysis of oxazolomycin (OZM) biosynthetic gene cluster from Streptomyces albus JA3453 revealed a gene, ozmH, encoding a hybrid polyketide and non-ribosomal peptide enzyme. Tandem ketosynthase (KS) domains (KS 10-1 and KS 10-2) were characterized and they show significant homology with known KSs. Using an alternative method that involves RecA-mediated homologous recombination, the negative selection marker sacB gene, and temperature-sensitive replications, site-directed mutagenesis of the catalytic triad amino acid cysteines were carried out in each of the tandem KS domains to test the function they play in OZM biosynthesis. HPLC-mass spectrometry analysis of the resulting mutant strains showed that KS 10-2 is essential for OZM biosynthesis but KS 10-1 is not indispensable and might serve as a "redundant" domain. These results confirmed the existence of an "extra domain" in complex polyketide synthase.
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Affiliation(s)
- Danfeng Song
- Laboratory of Microbial Metabolism and College of Life Sciences and Biotechnology, Shanghai Jiaotong University, Shanghai 200030, China
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Schuhmann T, Vollmar D, Grond S. Biosynthetic Origin of the Methoxyl Extender Unit in Bafilomycin and Concanamycin using Stereospecifically Labeled Precursors. J Antibiot (Tokyo) 2007; 60:52-60. [PMID: 17390589 DOI: 10.1038/ja.2007.7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
The microbial macrolides bafilomycin A1, B, and concanamycin A from Streptomyces spp. are potent and specific inhibitors of V-ATPases. The question of the biosynthetic origin of the two uncommon "glycolate units" of each of the macrolide structures was addressed by feeding experiments with stereospecifically 13C-labeled precursors. Our studies clearly indicate that glycerol is a source for the methoxylated C2-units and determines the orientation of the incorporation. Products from the carboxylic acid pool or TCA cycle are ruled out as key precursors. The data suggest the action of a glycerol kinase and point to phosphoglycerate as an intermediate in their biosynthesis. However, glycerate itself is not accepted as a precursor. We present the likely biosynthetic pathway and show the value of stereospecifically labeled presursors as an important tool for biosynthetic investigations.
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Affiliation(s)
- Tim Schuhmann
- Institut für Organische und Biomolekulare Chemie, Georg-August Universität Göttingen, Tammannstr. 2, Göttingen, Germany
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Deng Z, Bai L. Antibiotic biosynthetic pathways and pathway engineering--a growing research field in China. Nat Prod Rep 2006; 23:811-27. [PMID: 17003911 DOI: 10.1039/b611140h] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
This review describes the recent research activities in China in relation to studies on antibiotic biosynthetic pathways and pathway engineering in actinomycetes. 75 references are cited.
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Affiliation(s)
- Zixin Deng
- Laboratory of Microbial Metabolism and School of Life Science & Biotechnology, Shanghai Jiaotong University, Shanghai, 200030, China.
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Li W, Ju J, Osada H, Shen B. Utilization of the methoxymalonyl-acyl carrier protein biosynthesis locus for cloning of the tautomycin biosynthetic gene cluster from Streptomyces spiroverticillatus. J Bacteriol 2006; 188:4148-52. [PMID: 16707708 PMCID: PMC1482887 DOI: 10.1128/jb.00172-06] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Tautomycin (TTM), a potent protein phosphatase inhibitor, consists of a polyketide chain containing a spiroketal moiety and an acyl chain bearing a dialkylmaleic anhydride structure. PCR using degenerate primers was used to clone genes from Streptomyces spiroverticillatus for formation of the methoxymalonyl-acyl carrier protein. This locus was found to contain five genes (ttmC, ttmA, ttmD, ttmB, and ttmE), one of which was used as a probe to clone the 110-kb TTM biosynthetic gene cluster. The involvement of the ttmA gene in TTM biosynthesis was confirmed by gene inactivation and mutation complementation experiments.
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Affiliation(s)
- Wenli Li
- Division of Pharmaceutical Sciences, School of Pharmacy, University of Wisconsin-Madison, 777 Highland Ave., Madison, WI 53705, USA
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40
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Van Lanen SG, Shen B. Progress in combinatorial biosynthesis for drug discovery. DRUG DISCOVERY TODAY. TECHNOLOGIES 2006; 3:285-292. [PMID: 24980530 DOI: 10.1016/j.ddtec.2006.09.014] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/03/2023]
Abstract
Combinatorial biosynthesis, the process of genetic manipulations of natural product biosynthetic machinery for structural diversity, depends on several factors, and discussed here are two critical factors: access to genetic information and biochemical characterization of enzymes. Examples of the former include using predictions for the biosynthesis of unusual chemical entities such as aminohydroxybenzoic acid starter units, methoxymalonylate extender units, the enediyne core and bacterial aromatic polyketides. The latter aspect includes the continued elucidation of domain functionalities of modular polyketide synthases and nonribosomal peptide synthases and novel biochemical pathways such as the biosynthesis of a cyclopropyl unit and a β-hydroxyl acid. Finally, examples of successful combinatorial biosynthesis for daptomycin and indolocarbozole compounds are discussed.:
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Affiliation(s)
- Steven G Van Lanen
- Division of Pharmaceutical Sciences, University of Wisconsin, Madison, WI 53705, USA
| | - Ben Shen
- Department of Chemistry, University of Wisconsin, Madison, WI 53705, USA.
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