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Wang S, Zeng X, Jiang Y, Wang W, Bai L, Lu Y, Zhang L, Tan GY. Unleashing the potential: type I CRISPR-Cas systems in actinomycetes for genome editing. Nat Prod Rep 2024; 41:1441-1455. [PMID: 38888887 DOI: 10.1039/d4np00010b] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/20/2024]
Abstract
Covering: up to the end of 2023Type I CRISPR-Cas systems are widely distributed, found in over 40% of bacteria and 80% of archaea. Among genome-sequenced actinomycetes (particularly Streptomyces spp.), 45.54% possess type I CRISPR-Cas systems. In comparison to widely used CRISPR systems like Cas9 or Cas12a, these endogenous CRISPR-Cas systems have significant advantages, including better compatibility, wide distribution, and ease of operation (since no exogenous Cas gene delivery is needed). Furthermore, type I CRISPR-Cas systems can simultaneously edit and regulate genes by adjusting the crRNA spacer length. Meanwhile, most actinomycetes are recalcitrant to genetic manipulation, hindering the discovery and engineering of natural products (NPs). The endogenous type I CRISPR-Cas systems in actinomycetes may offer a promising alternative to overcome these barriers. This review summarizes the challenges and recent advances in CRISPR-based genome engineering technologies for actinomycetes. It also presents and discusses how to establish and develop genome editing tools based on type I CRISPR-Cas systems in actinomycetes, with the aim of their future application in gene editing and the discovery of NPs in actinomycetes.
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Affiliation(s)
- Shuliu Wang
- State Key Laboratory of Bioreactor Engineering (SKLBE), School of Biotechnology, East China University of Science and Technology (ECUST), Shanghai 200237, China.
| | - Xiaoqian Zeng
- State Key Laboratory of Bioreactor Engineering (SKLBE), School of Biotechnology, East China University of Science and Technology (ECUST), Shanghai 200237, China.
| | - Yue Jiang
- State Key Laboratory of Bioreactor Engineering (SKLBE), School of Biotechnology, East China University of Science and Technology (ECUST), Shanghai 200237, China.
| | - Weishan Wang
- State Key Laboratory of Microbial Resources and CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology, Chinese Academy of Sciences (CAS), Beijing 100101, China
| | - Linquan Bai
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Yinhua Lu
- College of Life Sciences, Shanghai Normal University, Shanghai 200234, China
| | - Lixin Zhang
- State Key Laboratory of Bioreactor Engineering (SKLBE), School of Biotechnology, East China University of Science and Technology (ECUST), Shanghai 200237, China.
| | - Gao-Yi Tan
- State Key Laboratory of Bioreactor Engineering (SKLBE), School of Biotechnology, East China University of Science and Technology (ECUST), Shanghai 200237, China.
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2
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Zhu B, Cen Z, Chen Y, Shang K, Zhai J, Han M, Wang J, Chen Z, Wei T, Han Z. α-Pyrone mediates quorum sensing through the conservon system in Nocardiopsis sp. Microbiol Res 2024; 285:127767. [PMID: 38776619 DOI: 10.1016/j.micres.2024.127767] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/30/2024] [Revised: 05/10/2024] [Accepted: 05/13/2024] [Indexed: 05/25/2024]
Abstract
Actinobacteria produce a plethora of bioactive secondary metabolites that are often regulated by quorum-sensing signaling molecules via specific binding to their cognate TetR-type receptors. Here, we identified monocyclic α-pyrone as a new class of actinobacterial signaling molecules influencing quorum sensing process in Nocardiopsis sp. LDBS0036, primarily evidenced by a significant reduction in the production of phenazines in the pyrone-null mutant compared to the wild-type strain. Exogenous addition of the α-pyrone can partially restore the expression of some pathways to the wild strain level. Moreover, a unique multicomponent system referred to as a conservon, which is widespread in actinobacteria and generally contains four or five functionally conserved proteins, may play an important role in detecting and transmitting α-pyrone signals in LDBS0036. We found the biosynthetic gene clusters of α-pyrone and their associated conservon genes are highly conserved in Nocardiopsis, indicating the widespread prevalence and significant function of this regulate mechanism within Nocardiopsis genus. Furthermore, homologous α-pyrones from different actinobacterial species were also found to mediate interspecies communication. Our results thus provide insights into a novel quorum-sensing signaling system and imply that various modes of bacterial communication remain undiscovered.
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Affiliation(s)
- Boyu Zhu
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Ziyun Cen
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Yiqiu Chen
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; Hainan University, Haikou, Hainan 570100, China
| | - Kun Shang
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China
| | - Ji'an Zhai
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Meigui Han
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Jiawei Wang
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; Hainan University, Haikou, Hainan 570100, China
| | - Zhiyong Chen
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China
| | - Taoshu Wei
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China; University of Chinese Academy of Sciences, Beijing 100049, China
| | - Zhuang Han
- Institute of Deep-sea Science and Engineering, Chinese Academy of Sciences, Sanya, Hainan 572000, China.
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3
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Liu G, An H, Tang L, Chi Z, Bi Y, Ye Z, Zhao H, Xiang L, Feng N, Mo C, Xu D. Activated DBP degradation and relevant signal transduction path via quorum sensing autoinducers in Streptomyces sp. SH5. JOURNAL OF HAZARDOUS MATERIALS 2024; 466:133571. [PMID: 38266588 DOI: 10.1016/j.jhazmat.2024.133571] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/18/2023] [Revised: 12/07/2023] [Accepted: 01/17/2024] [Indexed: 01/26/2024]
Abstract
Microbe-mediated DBP (dibutyl phthalate) mineralization is acknowledged to be affected by diverse extracellular factors. However, little is known about the regulatory effects from quorum sensing (QS) signals. In this study, extracellularly applied QS signals A-like (hydroxymethyl dihydrofuran) was discovered to significantly enhance DBP degradation efficiency in Streptomyces sp. SH5. Monobutyl phthalate, protocatechuic acid and beta-ketoadipate were discovered as degradation intermediates by HPLC-TOF-MS/MS. Multi-omics analysis revealed the up-regulation of multiple hydrolases, transferases and decarboxylases that potentially contributed to A-like accelerated DBP degradation. Transcription of Orf2708, an orthologue of global transcriptional activator, was significantly induced by A-like. Orf2708 was demonstrated to interact specifically with the promoter of hydrolase orf2879 gene by EMSA, and the overexpression of orf2879 led to an enhanced DBP degradation in SH5. Taken together with the molecular docking studies showing the stability of ligand-receptor complex of A-like and its potential receptor Orf3712, a hierarchical regulatory cascade underlying the QS signal mediated DBP degradation was proposed as A-like/Orf3712 duplex formation, enhanced orf2708 expression and the downstream specific activation of hydrolase Orf2879. Our study presents the first evidence of GBLs-type promoted DBP degradation among bacteria, and the elucidated signal transduction path indicates a universal application potential of this activation strategy.
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Affiliation(s)
- Ganxing Liu
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China
| | - Hao An
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China
| | - Lei Tang
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China
| | - Zhewei Chi
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China
| | - Yunwen Bi
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China
| | - Zeqi Ye
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China
| | - Haiming Zhao
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China
| | - Lei Xiang
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China
| | - Naixian Feng
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China.
| | - Cehui Mo
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China.
| | - Delin Xu
- Department of Ecology, Institute of Hydrobiology, School of Life Science and Technology, Key Laboratory of Eutrophication and Red Tide Prevention of Guangdong Higher Education Institutes, Engineering Research Center of Tropical and Subtropical Aquatic Ecological Engineering, Ministry of Education, Jinan University, Guangzhou 510632, PR China.
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Xu Z, Tian P. Rethinking Biosynthesis of Aclacinomycin A. Molecules 2023; 28:molecules28062761. [PMID: 36985733 PMCID: PMC10054333 DOI: 10.3390/molecules28062761] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2023] [Revised: 03/01/2023] [Accepted: 03/06/2023] [Indexed: 03/22/2023] Open
Abstract
Aclacinomycin A (ACM-A) is an anthracycline antitumor agent widely used in clinical practice. The current industrial production of ACM-A relies primarily on chemical synthesis and microbial fermentation. However, chemical synthesis involves multiple reactions which give rise to high production costs and environmental pollution. Microbial fermentation is a sustainable strategy, yet the current fermentation yield is too low to satisfy market demand. Hence, strain improvement is highly desirable, and tremendous endeavors have been made to decipher biosynthesis pathways and modify key enzymes. In this review, we comprehensively describe the reported biosynthesis pathways, key enzymes, and, especially, catalytic mechanisms. In addition, we come up with strategies to uncover unknown enzymes and improve the activities of rate-limiting enzymes. Overall, this review aims to provide valuable insights for complete biosynthesis of ACM-A.
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5
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Alwali AY, Parkinson EI. Small molecule inducers of actinobacteria natural product biosynthesis. J Ind Microbiol Biotechnol 2023; 50:kuad019. [PMID: 37587009 PMCID: PMC10549211 DOI: 10.1093/jimb/kuad019] [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: 05/22/2023] [Accepted: 08/14/2023] [Indexed: 08/18/2023]
Abstract
Actinobacteria are a large and diverse group of bacteria that are known to produce a wide range of secondary metabolites, many of which have important biological activities, including antibiotics, anti-cancer agents, and immunosuppressants. The biosynthesis of these compounds is often highly regulated with many natural products (NPs) being produced at very low levels in laboratory settings. Environmental factors, such as small molecule elicitors, can induce the production of secondary metabolites. Specifically, they can increase titers of known NPs as well as enabling discovery of novel NPs typically produced at undetectable levels. These elicitors can be NPs, including antibiotics or hormones, or synthetic compounds. In recent years, there has been a growing interest in the use of small molecule elicitors to induce the production of secondary metabolites from actinobacteria, especially for the discovery of NPs from "silent" biosynthetic gene clusters. This review aims to highlight classes of molecules that induce secondary metabolite production in actinobacteria and to describe the potential mechanisms of induction. ONE-SENTENCE SUMMARY This review describes chemical elicitors of actinobacteria natural products described to date and the proposed mechanisms of induction.
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Affiliation(s)
- Amir Y Alwali
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
| | - Elizabeth I Parkinson
- Department of Chemistry, Purdue University, West Lafayette, IN 47907, USA
- Department of Medicinal Chemistry and Molecular Pharmacology, Purdue University, West Lafayette, IN 47907, USA
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6
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Screening and engineering of high-activity promoter elements through transcriptomics and red fluorescent protein visualization in Rhodobacter sphaeroides. Synth Syst Biotechnol 2021; 6:335-342. [PMID: 34738044 PMCID: PMC8531756 DOI: 10.1016/j.synbio.2021.09.011] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2021] [Revised: 09/20/2021] [Accepted: 09/23/2021] [Indexed: 12/03/2022] Open
Abstract
The versatile photosynthetic α-proteobacterium Rhodobacter sphaeroides, has recently been extensively engineered as a novel microbial cell factory (MCF) to produce pharmaceuticals, nutraceuticals, commodity chemicals and even hydrogen. However, there are no well-characterized high-activity promoters to modulate gene transcription during the engineering of R. sphaeroides. In this study, several native promoters from R. sphaeroides JDW-710 (JDW-710), an industrial strain producing high levels of co-enzyme Q10 (Q10) were selected on the basis of transcriptomic analysis. These candidate promoters were then characterized by using gusA as a reporter gene. Two native promoters, Prsp_7571 and Prsp_6124, showed 620% and 800% higher activity, respectively, than the tac promoter, which has previously been used for gene overexpression in R. sphaeroides. In addition, a Prsp_7571-derived synthetic promoter library with strengths ranging from 54% to 3200% of that of the tac promoter, was created on the basis of visualization of red fluorescent protein (RFP) expression in R. sphaeroides. Finally, as a demonstration, the synthetic pathway of Q10 was modulated by the selected promoter T334* in JDW-710; the Q10 yield in shake-flasks increased 28% and the production reached 226 mg/L. These well-characterized promoters should be highly useful in current synthetic biology platforms for refactoring the biosynthetic pathway in R. sphaeroides-derived MCFs.
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7
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Sharma V, Kaur R, Salwan R. Streptomyces: host for refactoring of diverse bioactive secondary metabolites. 3 Biotech 2021; 11:340. [PMID: 34221811 DOI: 10.1007/s13205-021-02872-y] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/12/2021] [Accepted: 05/31/2021] [Indexed: 12/22/2022] Open
Abstract
Microbial secondary metabolites are intensively explored due to their demands in pharmaceutical, agricultural and food industries. Streptomyces are one of the largest sources of secondary metabolites having diverse applications. In particular, the abundance of secondary metabolites encoding biosynthetic gene clusters and presence of wobble position in Streptomyces strains make it potential candidate as a native or heterologous host for secondary metabolite production including several cryptic gene clusters expression. Here, we have discussed the developments in Streptomyces strains genome mining, its exploration as a suitable host and application of synthetic biology for refactoring genetic systems for developing chassis for enhanced as well as novel secondary metabolites with reduced genome and cleaned background.
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Affiliation(s)
- Vivek Sharma
- University Centre for Research and Development, Chandigarh University, Gharuan, Mohali, Punjab 140413 India
| | - Randhir Kaur
- University Centre for Research and Development, Chandigarh University, Gharuan, Mohali, Punjab 140413 India
| | - Richa Salwan
- College of Horticulture and Forestry, Dr YS Parmar University of Horticulture and Forestry, Neri, Hamirpur, Himachal Pradesh 177001 India
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8
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Handel F, Kulik A, Mast Y. Investigation of the Autoregulator-Receptor System in the Pristinamycin Producer Streptomyces pristinaespiralis. Front Microbiol 2020; 11:580990. [PMID: 33101255 PMCID: PMC7554373 DOI: 10.3389/fmicb.2020.580990] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Accepted: 09/10/2020] [Indexed: 12/19/2022] Open
Abstract
Pristinamycin biosynthesis in Streptomyces pristinaespiralis is governed by a complex hierarchical signaling cascade involving seven different transcriptional regulators (SpbR, PapR1, PapR2, PapR3, PapR4, PapR5, and PapR6). The signaling cascade is triggered by γ-butyrolactone (GBL)-like effector molecules, whereby the chemical structure of the effector, as well as its biosynthetic origin is unknown so far. Three of the pristinamycin transcriptional regulators (SpbR, PapR3, and PapR5) belong to the type of γ-butyrolactone receptor (GBLR). GBLRs are known to either act as “real” GBLRs, which bind GBLs as ligands or as “pseudo” GBLRs binding antibiotics or intermediates thereof as effector molecules. In this study, we performed electromobility shift assays (EMSAs) with SpbR, PapR3, and PapR5, respectively, in the presence of potential ligand samples. Thereby we could show that all three GBLRs bind synthetic 1,4-butyrolactone but not pristinamycin as ligand, suggesting that SpbR, PapR3, and PapR5 act as “real” GBLRs in S. pristinaespiralis. Furthermore, we identified a cytochrome P450 monooxygenase encoding gene snbU as potential biosynthesis gene for the GBLR-interacting ligand. Inactivation of snbU resulted in an increased pristinamycin production, which indicated that SnbU has a regulatory influence on pristinamycin production. EMSAs with culture extract samples from the snbU mutant did not influence the target binding ability of SpbR, PapR3, and PapR5 anymore, in contrast to culture supernatant samples from the S. pristinaespiralis wild-type or the pristinamycin deficient mutant papR2::apra, which demonstrates that SnbU is involved in the synthesis of the GBLR-interacting ligand.
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Affiliation(s)
- Franziska Handel
- Department of Microbiology/Biotechnology, Faculty of Science, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Andreas Kulik
- Department of Microbiology/Biotechnology, Faculty of Science, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany
| | - Yvonne Mast
- Department of Microbiology/Biotechnology, Faculty of Science, Interfaculty Institute of Microbiology and Infection Medicine, University of Tübingen, Tübingen, Germany.,German Center for Infection Research (DZIF), Partner Site Tübingen, Tübingen, Germany.,Department Bioresources for Bioeconomy and Health Research, Leibniz Institute DSMZ - German Collection of Microorganisms and Cell Cultures, Braunschweig, Germany.,Department of Microbiology, Technical University Braunschweig, Braunschweig, Germany
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9
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Wu Y, Kang Q, Zhang LL, Bai L. Subtilisin-Involved Morphology Engineering for Improved Antibiotic Production in Actinomycetes. Biomolecules 2020; 10:biom10060851. [PMID: 32503302 PMCID: PMC7356834 DOI: 10.3390/biom10060851] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 05/27/2020] [Accepted: 05/30/2020] [Indexed: 12/27/2022] Open
Abstract
In the submerged cultivation of filamentous microbes, including actinomycetes, complex morphology is one of the critical process features for the production of secondary metabolites. Ansamitocin P-3 (AP-3), an antitumor agent, is a secondary metabolite produced by Actinosynnema pretiosum ATCC 31280. An excessive mycelial fragmentation of A. pretiosum ATCC 31280 was observed during the early stage of fermentation. Through comparative transcriptomic analysis, a subtilisin-like serine peptidase encoded gene APASM_4178 was identified to be responsible for the mycelial fragmentation. Mutant WYT-5 with the APASM_4178 deletion showed increased biomass and improved AP-3 yield by 43.65%. We also found that the expression of APASM_4178 is specifically regulated by an AdpA-like protein APASM_1021. Moreover, the mycelial fragmentation was alternatively alleviated by the overexpression of subtilisin inhibitor encoded genes, which also led to a 46.50 ± 0.79% yield increase of AP-3. Furthermore, APASM_4178 was overexpressed in salinomycin-producing Streptomyces albus BK 3-25 and validamycin-producing S. hygroscopicus TL01, which resulted in not only dispersed mycelia in both strains, but also a 33.80% yield improvement of salinomycin to 24.07 g/L and a 14.94% yield improvement of validamycin to 21.46 g/L. In conclusion, our work elucidates the involvement of a novel subtilisin-like serine peptidase in morphological differentiation, and modulation of its expression could be an effective strategy for morphology engineering and antibiotic yield improvement in actinomycetes.
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Affiliation(s)
- Yuanting Wu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200204, China; (Y.W.); (Q.K.)
- Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Qianjin Kang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200204, China; (Y.W.); (Q.K.)
- Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Li-Li Zhang
- College of Life Science, Tarim University, Alar 843300, China;
| | - Linquan Bai
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200204, China; (Y.W.); (Q.K.)
- Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
- College of Life Science, Tarim University, Alar 843300, China;
- Correspondence:
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10
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Lu ZY, Zhong JJ. Effect of furfural addition on validamycin-A production in fermentation of Streptomyces hygroscopicus 5008. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.03.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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11
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Li JW, Zhang XY, Wu H, Bai YP. Transcription Factor Engineering for High-Throughput Strain Evolution and Organic Acid Bioproduction: A Review. Front Bioeng Biotechnol 2020; 8:98. [PMID: 32140463 PMCID: PMC7042172 DOI: 10.3389/fbioe.2020.00098] [Citation(s) in RCA: 20] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2019] [Accepted: 02/03/2020] [Indexed: 01/15/2023] Open
Abstract
Metabolic regulation of gene expression for the microbial production of fine chemicals, such as organic acids, is an important research topic in post-genomic metabolic engineering. In particular, the ability of transcription factors (TFs) to respond precisely in time and space to various small molecules, signals and stimuli from the internal and external environment is essential for metabolic pathway engineering and strain development. As a key component, TFs are used to construct many biosensors in vivo using synthetic biology methods, which can be used to monitor the concentration of intracellular metabolites in organic acid production that would otherwise remain “invisible” within the intracellular environment. TF-based biosensors also provide a high-throughput screening method for rapid strain evolution. Furthermore, TFs are important global regulators that control the expression levels of key enzymes in organic acid biosynthesis pathways, therefore determining the outcome of metabolic networks. Here we review recent advances in TF identification, engineering, and applications for metabolic engineering, with an emphasis on metabolite monitoring and high-throughput strain evolution for the organic acid bioproduction.
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Affiliation(s)
- Jia-Wei Li
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Xiao-Yan Zhang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Hui Wu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
| | - Yun-Peng Bai
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai, China
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12
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Kong D, Wang X, Nie J, Niu G. Regulation of Antibiotic Production by Signaling Molecules in Streptomyces. Front Microbiol 2019; 10:2927. [PMID: 31921086 PMCID: PMC6930871 DOI: 10.3389/fmicb.2019.02927] [Citation(s) in RCA: 28] [Impact Index Per Article: 5.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 12/05/2019] [Indexed: 11/22/2022] Open
Abstract
The genus Streptomyces is a unique subgroup of actinomycetes bacteria that are well-known as prolific producers of antibiotics and many other bioactive secondary metabolites. Various environmental and physiological signals affect the onset and level of production of each antibiotic. Here we highlight recent findings on the regulation of antibiotic biosynthesis in Streptomyces by signaling molecules, with special focus on autoregulators such as hormone-like signaling molecules and antibiotics themselves. Hormone-like signaling molecules are a group of small diffusible signaling molecules that interact with specific receptor proteins to initiate complex regulatory cascades of antibiotic biosynthesis. Antibiotics and their biosynthetic intermediates can also serve as autoregulators to fine-tune their own biosynthesis or cross-regulators of disparate biosynthetic pathways. Advances in understanding of signaling molecules-mediated regulation of antibiotic production in Streptomyces may aid the discovery of new signaling molecules and their use in eliciting silent antibiotic biosynthetic pathways in a wide range of actinomycetes.
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Affiliation(s)
- Dekun Kong
- Biotechnology Research Center, Southwest University, Chongqing, China.,State Cultivation Base of Crop Stress Biology for Southern Mountainous Land, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Xia Wang
- Biotechnology Research Center, Southwest University, Chongqing, China.,State Cultivation Base of Crop Stress Biology for Southern Mountainous Land, Academy of Agricultural Sciences, Southwest University, Chongqing, China
| | - Ju Nie
- Biotechnology Research Center, Southwest University, Chongqing, China.,College of Horticulture and Landscape Architecture, Southwest University, Chongqing, China
| | - Guoqing Niu
- Biotechnology Research Center, Southwest University, Chongqing, China.,State Cultivation Base of Crop Stress Biology for Southern Mountainous Land, Academy of Agricultural Sciences, Southwest University, Chongqing, China
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13
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Gao X, Wang Y, Chu J. A preliminary study on the impact of exogenous A-Factor analogue 1,4-butyrolactone on stimulating bitespiramycin biosynthesis. Bioprocess Biosyst Eng 2019; 42:1903-1913. [PMID: 31471709 DOI: 10.1007/s00449-019-02184-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2019] [Revised: 07/10/2019] [Accepted: 07/23/2019] [Indexed: 02/06/2023]
Abstract
Bitespiramycin is composed of nine main acylated spiramycin components with isovaleryspiramycin as the major component. However, even with excellent therapeutic effects, its application and industrialization are restricted due to its low titer. In this study, the exogenous addition of A-Factor analogue 1,4-butyrolactone (1,4-BL) stimulated an improvement in bitespiramycin biological titer by 29% with a tiny influence on concentration of major component. Moreover, the mechanism of 1,4-BL stimulating effect was preliminarily explored by the analyses of three key enzyme activities, intracellular metabolite profiling and metabolic flux distribution. All results coordinately revealed that the extensive accumulation of methylmalonyl-CoA and acetyl-CoA was the direct reason for the enhanced bitespiramycin biosynthesis. This study would provide theoretical and technical basis for the application of 1,4-BL addition strategy to industrial bitespiramycin production.
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Affiliation(s)
- Xiaowei Gao
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P. O. Box 329#, Shanghai, 200237, People's Republic of China
| | - Yonghong Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P. O. Box 329#, Shanghai, 200237, People's Republic of China.
| | - Ju Chu
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, 130 Meilong Road, P. O. Box 329#, Shanghai, 200237, People's Republic of China.
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A Novel AdpA Homologue Negatively Regulates Morphological Differentiation in Streptomyces xiamenensis 318. Appl Environ Microbiol 2019; 85:AEM.03107-18. [PMID: 30683747 DOI: 10.1128/aem.03107-18] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/25/2018] [Accepted: 01/23/2019] [Indexed: 11/20/2022] Open
Abstract
The pleiotropic transcriptional regulator AdpA positively controls morphological differentiation and regulates secondary metabolism in most Streptomyces species. Streptomyces xiamenensis 318 has a linear chromosome 5.96 Mb in size. How AdpA affects secondary metabolism and morphological differentiation in such a naturally minimized genomic background is unknown. Here, we demonstrated that AdpA Sx , an AdpA orthologue in S. xiamenensis, negatively regulates cell growth and sporulation and bidirectionally regulates the biosynthesis of xiamenmycin and polycyclic tetramate macrolactams (PTMs) in S. xiamenensis 318. Overexpression of the adpASx gene in S. xiamenensis 318 had negative effects on morphological differentiation and resulted in reduced transcription of putative ssgA, ftsZ, ftsH, amfC, whiB, wblA1, wblA2, wblE, and a gene encoding sporulation-associated protein (sxim_29740), whereas the transcription of putative bldD and bldA genes was upregulated. Overexpression of adpASx led to significantly enhanced production of xiamenmycin but had detrimental effects on the production of PTMs. As expected, the transcriptional level of the xim gene cluster was upregulated, whereas the PTM gene cluster was downregulated. Moreover, AdpA Sx negatively regulated the transcription of its own gene. Electrophoretic mobility shift assays revealed that AdpA Sx can bind the promoter regions of structural genes of both the xim and PTM gene clusters as well as to the promoter regions of genes potentially involved in the cell growth and differentiation of S. xiamenensis 318. We report that an AdpA homologue has negative effects on morphological differentiation in S. xiamenensis 318, a finding confirmed when AdpA Sx was introduced into the heterologous host Streptomyces lividans TK24.IMPORTANCE AdpA is a key regulator of secondary metabolism and morphological differentiation in Streptomyces species. However, AdpA had not been reported to negatively regulate morphological differentiation. Here, we characterized the regulatory role of AdpA Sx in Streptomyces xiamenensis 318, which has a naturally streamlined genome. In this strain, AdpA Sx negatively regulated cell growth and morphological differentiation by directly controlling genes associated with these functions. AdpA Sx also bidirectionally controlled the biosynthesis of xiamenmycin and PTMs by directly regulating their gene clusters rather than through other regulators. Our findings provide additional evidence for the versatility of AdpA in regulating morphological differentiation and secondary metabolism in Streptomyces.
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15
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Wang M, Wang T, Guan Y, Wang F, Zhu J. The preparation and therapeutic roles of scFv-Fc antibody against Staphylococcus aureus infection to control bovine mastitis. Appl Microbiol Biotechnol 2019; 103:1703-1712. [PMID: 30607490 DOI: 10.1007/s00253-018-9548-6] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2018] [Revised: 11/27/2018] [Accepted: 11/28/2018] [Indexed: 01/30/2023]
Abstract
Staphylococcus aureus-induced bovine mastitis causes significant losses to the dairy industry and available vaccines do not confer adequate protection. As a more attractive alternative, we propose the use of antibody (Ab) therapy. In our previous study, we constructed a bovine single-chain variable fragment (scFv) Ab phage display and successfully obtained scFvs that bound to S. aureus antigens with high affinity. Here, we describe a novel Ab against S. aureus (scFv-Fc Ab). To construct the scFv-Fc Ab, the scFv Ab was genetically fused to the Fc fragment of a bovine IgG1 Ab. Western blot analysis showed that the bovine scFvs-Fc Abs were successfully expressed with horseradish peroxidase-conjugated goat-anti-bovine IgG (Fc) Ab in Escherichia coli cells. The purified bovine scFvs-Fc Abs had good binding activity to S. aureus and effectively inhibited the bacterial growth in culture medium and bovine scFvs-Fc Abs enhanced phagocytosis of S. aureus by neutrophils isolated from peripheral blood in a dose-dependent manner. In the experiment of bovine scFvs-Fc Abs for the treatment of S. aureus-induced bovine mastitis, the total effective percentage reached 82% (9/11). These novel bovine scFvs-Fc Abs may be useful as therapeutic candidates for the prevention and treatment of S. aureus-induced bovine mastitis.
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Affiliation(s)
- Man Wang
- Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Tingting Wang
- Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Yu Guan
- Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Fengqing Wang
- Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 800 Dongchuan Road, Shanghai, 200240, China
| | - Jianguo Zhu
- Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 800 Dongchuan Road, Shanghai, 200240, China.
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16
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Wang T, Zhao X, Shi H, Sun L, Li Y, Li Q, Zhang H, Chen S, Li J. Positive and negative regulation of transferred nif genes mediated by indigenous GlnR in Gram-positive Paenibacillus polymyxa. PLoS Genet 2018; 14:e1007629. [PMID: 30265664 PMCID: PMC6191146 DOI: 10.1371/journal.pgen.1007629] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Revised: 10/16/2018] [Accepted: 08/14/2018] [Indexed: 12/29/2022] Open
Abstract
Ammonia is a major signal that regulates nitrogen fixation in most diazotrophs. Regulation of nitrogen fixation by ammonia in the Gram-negative diazotrophs is well-characterized. In these bacteria, this regulation occurs mainly at the level of nif (nitrogen fixation) gene transcription, which requires a nif-specific activator, NifA. Although Gram-positive and diazotrophic Paenibacilli have been extensively used as a bacterial fertilizer in agriculture, how nitrogen fixation is regulated in response to nitrogen availability in these bacteria remains unclear. An indigenous GlnR and GlnR/TnrA-binding sites in the promoter region of the nif cluster are conserved in these strains, indicating the role of GlnR as a regulator of nitrogen fixation. In this study, we for the first time reveal that GlnR of Paenibacillus polymyxa WLY78 is essentially required for nif gene transcription under nitrogen limitation, whereas both GlnR and glutamine synthetase (GS) encoded by glnA within glnRA operon are required for repressing nif expression under excess nitrogen. Dimerization of GlnR is necessary for binding of GlnR to DNA. GlnR in P. polymyxa WLY78 exists in a mixture of dimers and monomers. The C-terminal region of GlnR monomer is an autoinhibitory domain that prevents GlnR from binding DNA. Two GlnR-biding sites flank the -35/-10 regions of the nif promoter of the nif operon (nifBHDKENXhesAnifV). The GlnR-binding site Ⅰ (located upstream of -35/-10 regions of the nif promoter) is specially required for activating nif transcription, while GlnR-binding siteⅡ (located downstream of -35/-10 regions of the nif promoter) is for repressing nif expression. Under nitrogen limitation, GlnR dimer binds to GlnR-binding siteⅠ in a weak and transient association way and then activates nif transcription. During excess nitrogen, glutamine binds to and feedback inhibits GS by forming the complex FBI-GS. The FBI-GS interacts with the C-terminal domain of GlnR and stabilizes the binding affinity of GlnR to GlnR-binding site Ⅱ and thus represses nif transcription. GlnR is a global transcription regulator of nitrogen metabolism in Bacillus and other Gram-positive bacteria. GlnR generally functions as repressor and inhibits gene transcription under excess nitrogen. Our study for the first time reveals that GlnR simultaneously acted as an activator and a repressor for nitrogen fixation of Paenibacillus by binding to different loci of the single nif promoter region according to nitrogen availability. In excess glutamine, the feedback inhibited form of glutamine synthetase (GS) encoded by glnA within glnRA operon directly interacts with the C-terminal domain of GlnR and then controls the GlnR activity. Also, overexpression of glnR or deletion of glnA or mutagenesis of GlnR-binding site Ⅱ led to constitutive nif expression in the absence or presence of high (100 mM) concentration of ammonia. This work represents the first instance of a dual positive and negative regulatory mechanism of nitrogen fixation.
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Affiliation(s)
- Tianshu Wang
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
| | - Xiyun Zhao
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
| | - Haowen Shi
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
| | - Li Sun
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
| | - Yongbin Li
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
| | - Qin Li
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
| | - Haowei Zhang
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
| | - Sanfeng Chen
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
- * E-mail:
| | - Jilun Li
- State Key Laboratory for Agrobiotechnology, Key Laboratory of Soil Microbiology of Agriculture Ministry and College of Biological Sciences, China Agricultural University, Beijing, P. R. China
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17
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Abstract
Pseudo-oligosaccharides are microbial-derived secondary metabolites whose chemical structures contain pseudosugars (glycomimetics). Due to their high resemblance to the molecules of life (carbohydrates), most pseudo-oligosaccharides show significant biological activities. Some of them have been used as drugs to treat human and plant diseases. Because of their significant economic value, efforts have been put into understanding their biosynthesis, optimizing their fermentation conditions, and engineering their metabolic pathways to obtain better production yields. A number of unusual enzymes participating in diverse biosynthetic pathways to pseudo-oligosaccharides have been reported. Various methods and conditions to improve the production yields of the target compounds and eliminate byproducts have also been developed. This review article describes recent studies on the biosynthesis, fermentation optimization, and metabolic engineering of high-value pseudo-oligosaccharides.
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18
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He H, Ye L, Li C, Wang H, Guo X, Wang X, Zhang Y, Xiang W. SbbR/SbbA, an Important ArpA/AfsA-Like System, Regulates Milbemycin Production in Streptomyces bingchenggensis. Front Microbiol 2018; 9:1064. [PMID: 29875761 PMCID: PMC5974925 DOI: 10.3389/fmicb.2018.01064] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/05/2018] [Accepted: 05/04/2018] [Indexed: 12/17/2022] Open
Abstract
Milbemycins, a group of 16-membered macrolide antibiotics, are used widely as insecticides and anthelmintics. Previously, a limited understanding of the transcriptional regulation of milbemycin biosynthesis has hampered efforts to enhance antibiotic production by engineering of regulatory genes. Here, a novel ArpA/AfsA-type system, SbbR/SbbA (SBI_08928/SBI_08929), has been identified to be involved in regulating milbemycin biosynthesis in the industrial strain S. bingchenggensis BC04. Inactivation of sbbR in BC04 resulted in markedly decreased production of milbemycin, while deletion of sbbA enhanced milbemycin production. Electrophoresis mobility shift assays (EMSAs) and DNase I footprinting studies showed that SbbR has a specific DNA-binding activity for the promoters of milR (the cluster-situated activator gene for milbemycin production) and the bidirectionally organized genes sbbR and sbbA. Transcriptional analysis suggested that SbbR directly activates the transcription of milR, while represses its own transcription and that of sbbA. Moreover, 11 novel targets of SbbR were additionally found, including seven regulatory genes located in secondary metabolite biosynthetic gene clusters (e.g., sbi_08420, sbi_08432, sbi_09158, sbi_00827, sbi_01376, sbi_09325, and sig24sbh) and four well-known global regulatory genes (e.g., glnRsbh, wblAsbh, atrAsbh, and mtrA/Bsbh). These data suggest that SbbR is not only a direct activator of milbemycin production, but also a pleiotropic regulator that controls the expression of other cluster-situated regulatory genes and global regulatory genes. Overall, this study reveals the upper-layer regulatory system that controls milbemycin biosynthesis, which will not only expand our understanding of the complex regulation in milbemycin biosynthesis, but also provide a basis for an approach to improve milbemycin production via genetic manipulation of SbbR/SbbA system.
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Affiliation(s)
- Hairong He
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.,School of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Lan Ye
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.,School of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Chuang Li
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.,School of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Haiyan Wang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Xiaowei Guo
- School of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Xiangjing Wang
- School of Life Sciences, Northeast Agricultural University, Harbin, China
| | - Yanyan Zhang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China
| | - Wensheng Xiang
- State Key Laboratory for Biology of Plant Diseases and Insect Pests, Institute of Plant Protection, Chinese Academy of Agricultural Sciences, Beijing, China.,School of Life Sciences, Northeast Agricultural University, Harbin, China
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19
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Tan GY, Deng K, Liu X, Tao H, Chang Y, Chen J, Chen K, Sheng Z, Deng Z, Liu T. Heterologous Biosynthesis of Spinosad: An Omics-Guided Large Polyketide Synthase Gene Cluster Reconstitution in Streptomyces. ACS Synth Biol 2017; 6:995-1005. [PMID: 28264562 DOI: 10.1021/acssynbio.6b00330] [Citation(s) in RCA: 66] [Impact Index Per Article: 9.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
With the advent of the genomics era, heterologous gene expression has been used extensively as a means of accessing natural products (NPs) from environmental DNA samples. However, the heterologous production of NPs often has very low efficiency or is unable to produce targeted NPs. Moreover, due to the complicated transcriptional and metabolic regulation of NP biosynthesis in native producers, especially in the cases of genome mining, it is also difficult to rationally and systematically engineer synthetic pathways to improved NPs biosynthetic efficiency. In this study, various strategies ranging from heterologous production of a NP to subsequent application of omics-guided synthetic modules optimization for efficient biosynthesis of NPs with complex structure have been developed. Heterologous production of spinosyn in Streptomyces spp. has been demonstrated as an example of the application of these approaches. Combined with the targeted omics approach, several rate-limiting steps of spinosyn heterologous production in Streptomyces spp. have been revealed. Subsequent engineering work overcame three of selected rate-limiting steps, and the production of spinosad was increased step by step and finally reached 1460 μg/L, which is about 1000-fold higher than the original strain S. albus J1074 (C4I6-M). These results indicated that the omics platform developed in this work was a powerful tool for guiding the rational refactoring of heterologous biosynthetic pathway in Streptomyces host. Additionally, this work lays the foundation for further studies aimed at the more efficient production of spinosyn in a heterologous host. And the strategy developed in this study is expected to become readily adaptable to highly efficient heterologous production of other NPs with complex structure.
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Affiliation(s)
- Gao-Yi Tan
- Key
Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan
University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China
- State
Key Laboratory of Bioreactor Engineering, School of Bioengineering, East China University of Science and Technology, 130 Meilong Road, Shanghai 200237, China
| | - Kunhua Deng
- Key
Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan
University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China
- Hubei
Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan 430075, China
| | - Xinhua Liu
- Key
Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan
University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China
- Hubei
Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan 430075, China
| | - Hui Tao
- Key
Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan
University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China
- Hubei
Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan 430075, China
| | - Yingying Chang
- Key
Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan
University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China
- Hubei
Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan 430075, China
| | - Jia Chen
- Key
Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan
University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China
- Hubei
Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan 430075, China
| | - Kai Chen
- Shenyang Research Institute of Chemical Industry Ltd., Co., SINOCHEM Group, Shengyang 110021, China
| | - Zhi Sheng
- Shenyang Research Institute of Chemical Industry Ltd., Co., SINOCHEM Group, Shengyang 110021, China
| | - Zixin Deng
- Key
Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan
University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China
- Hubei
Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan 430075, China
- State Key Laboratory of Microbial Metabolism, and School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, 800 Dongchuan Road, Shanghai 200240, China
| | - Tiangang Liu
- Key
Laboratory of Combinatorial Biosynthesis and Drug Discovery (Wuhan
University), Ministry of Education, and Wuhan University School of Pharmaceutical Sciences, Wuhan 430071, China
- Hubei
Engineering Laboratory for Synthetic Microbiology, Wuhan Institute of Biotechnology, Wuhan 430075, China
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20
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Tan GY, Liu T. Rational synthetic pathway refactoring of natural products biosynthesis in actinobacteria. Metab Eng 2017; 39:228-236. [DOI: 10.1016/j.ymben.2016.12.006] [Citation(s) in RCA: 47] [Impact Index Per Article: 6.7] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2016] [Revised: 10/31/2016] [Accepted: 12/05/2016] [Indexed: 11/28/2022]
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21
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Zhang MM, Wang Y, Ang EL, Zhao H. Engineering microbial hosts for production of bacterial natural products. Nat Prod Rep 2016; 33:963-87. [PMID: 27072804 PMCID: PMC4963277 DOI: 10.1039/c6np00017g] [Citation(s) in RCA: 94] [Impact Index Per Article: 11.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
Abstract
Covering up to end 2015Microbial fermentation provides an attractive alternative to chemical synthesis for the production of structurally complex natural products. In most cases, however, production titers are low and need to be improved for compound characterization and/or commercial production. Owing to advances in functional genomics and genetic engineering technologies, microbial hosts can be engineered to overproduce a desired natural product, greatly accelerating the traditionally time-consuming strain improvement process. This review covers recent developments and challenges in the engineering of native and heterologous microbial hosts for the production of bacterial natural products, focusing on the genetic tools and strategies for strain improvement. Special emphasis is placed on bioactive secondary metabolites from actinomycetes. The considerations for the choice of host systems will also be discussed in this review.
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Affiliation(s)
- Mingzi M Zhang
- Metabolic Engineering Research Laboratory, Science and Engineering Institutes, Agency for Science, Technology and Research, Singapore
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22
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Niu G, Chater KF, Tian Y, Zhang J, Tan H. Specialised metabolites regulating antibiotic biosynthesis in Streptomyces spp. FEMS Microbiol Rev 2016; 40:554-73. [PMID: 27288284 DOI: 10.1093/femsre/fuw012] [Citation(s) in RCA: 91] [Impact Index Per Article: 11.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 05/16/2016] [Indexed: 12/11/2022] Open
Abstract
Streptomyces bacteria are the major source of antibiotics and other secondary metabolites. Various environmental and physiological conditions affect the onset and level of production of each antibiotic by influencing concentrations of the ligands for conserved global regulatory proteins. In addition, as reviewed here, well-known autoregulators such as γ-butyrolactones, themselves products of secondary metabolism, accumulate late in growth to concentrations allowing their effective interaction with cognate binding proteins, in a necessary prelude to antibiotic biosynthesis. Most autoregulator binding proteins target the conserved global regulatory gene adpA, and/or regulatory genes for 'cluster-situated regulators' (CSRs) linked to antibiotic biosynthetic gene clusters. It now appears that some CSRs bind intermediates and end products of antibiotic biosynthesis, with regulatory effects interwoven with those of autoregulators. These ligands can exert cross-pathway effects within producers of more than one antibiotic, and when excreted into the extracellular environment may have population-wide effects on production, and mediate interactions with neighbouring microorganisms in natural communities, influencing speciation. Greater understanding of these autoregulatory and cross-regulatory activities may aid the discovery of new signalling molecules and their use in activating cryptic antibiotic biosynthetic pathways.
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Affiliation(s)
- Guoqing Niu
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Keith F Chater
- Department of Molecular Microbiology, John Innes Centre, Norwich Research Park, Norwich, UK
| | - Yuqing Tian
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Jihui Zhang
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
| | - Huarong Tan
- State Key Laboratory of Microbial Resources, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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23
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Wang M, Zhang Y, Zhu J. Anti-Staphylococcus aureus single-chain variable region fragments provide protection against mastitis in mice. Appl Microbiol Biotechnol 2015; 100:2153-62. [PMID: 26512007 DOI: 10.1007/s00253-015-7045-8] [Citation(s) in RCA: 11] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/13/2015] [Revised: 09/04/2015] [Accepted: 09/25/2015] [Indexed: 11/27/2022]
Abstract
Staphylococcus aureus is a leading causative agent of bovine mastitis, which can result in significant economic losses to the dairy industry. However, available vaccines against bovine mastitis do not confer adequate protection, although passive immunization with antibodies may be useful to prevent disease. Hence, we constructed a bovine single-chain variable region fragment (scFv) phage display library using cDNAs from peripheral blood lymphocytes of cows with S. aureus-induced mastitis. After four rounds of selection, eight scFvs that bound S. aureus antigens with high affinity were obtained. The framework regions of the variable domains (VH and VL) of the eight scFvs were highly conserved, and the complementarity-determining regions (CDRs) displayed significant diversity, especially CDR3 of the VH domain. All eight scFvs inhibited S. aureus growth in culture medium. Lactating mice were challenged by injecting S. aureus into the fourth mammary gland. Histopathological analysis showed that treatment with these scFvs prior to bacterial challenge maintained the structure of the mammary acini, decreased infiltration of polymorphonuclear neutrophils, increased levels of interferon-gamma and interleukin-4, and reduced tumor necrosis factor-alpha levels in mammary tissues, as compared with mice treatment with physiological saline (P < 0.05). These novel bovine scFvs may be suitable candidates for therapeutic agents for the prevention of S. aureus-induced bovine mastitis.
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Affiliation(s)
- Man Wang
- Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 800 Dongchuan Road, Shanghai, 200240, People's Republic of China
| | - Yan Zhang
- Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 800 Dongchuan Road, Shanghai, 200240, People's Republic of China
| | - Jianguo Zhu
- Shanghai Key Laboratory of Veterinary Biotechnology, School of Agriculture and Biology, Shanghai JiaoTong University, 800 Dongchuan Road, Shanghai, 200240, People's Republic of China.
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24
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Biarnes-Carrera M, Breitling R, Takano E. Butyrolactone signalling circuits for synthetic biology. Curr Opin Chem Biol 2015; 28:91-8. [PMID: 26164547 DOI: 10.1016/j.cbpa.2015.06.024] [Citation(s) in RCA: 31] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2015] [Revised: 06/16/2015] [Accepted: 06/20/2015] [Indexed: 01/14/2023]
Abstract
Signalling circuits based on quorum sensing mechanisms have been popular tools for synthetic biology. Recent advances in our understanding of the analogous systems regulating antibiotics production in soil bacteria suggest that these might provide useful complementary tools to increase the complexity of possible circuit designs. Here we discuss the diversity of these natural circuits, which use γ-butyrolactones (GBLs) as their main inter-cellular signal, highlighting the range of new building blocks they could provide, as well as a number of exciting recent applications of GBL-based circuits in heterologous systems. We conclude by presenting examples of the novel circuit complexity that could become accessible through the use of GBL-based designs.
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Affiliation(s)
- Marc Biarnes-Carrera
- Manchester Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM), Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Rainer Breitling
- Manchester Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM), Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom
| | - Eriko Takano
- Manchester Centre for Synthetic Biology of Fine and Speciality Chemicals (SYNBIOCHEM), Manchester Institute of Biotechnology, Faculty of Life Sciences, University of Manchester, 131 Princess Street, Manchester M1 7DN, United Kingdom.
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Antoraz S, Santamaría RI, Díaz M, Sanz D, Rodríguez H. Toward a new focus in antibiotic and drug discovery from the Streptomyces arsenal. Front Microbiol 2015; 6:461. [PMID: 26029195 PMCID: PMC4429630 DOI: 10.3389/fmicb.2015.00461] [Citation(s) in RCA: 43] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/06/2015] [Accepted: 04/28/2015] [Indexed: 11/13/2022] Open
Abstract
Emergence of antibiotic resistant pathogens is changing the way scientists look for new antibiotic compounds. This race against the increased prevalence of multi-resistant strains makes it necessary to expedite the search for new compounds with antibiotic activity and to increase the production of the known. Here, we review a variety of new scientific approaches aiming to enhance antibiotic production in Streptomyces. These include: (i) elucidation of the signals that trigger the antibiotic biosynthetic pathways to improve culture media, (ii) bacterial hormone studies aiming to reproduce intra and interspecific communications resulting in antibiotic burst, (iii) co-cultures to mimic competition-collaboration scenarios in nature, and (iv) the very recent in situ search for antibiotics that might be applied in Streptomyces natural habitats. These new research strategies combined with new analytical and molecular techniques should accelerate the discovery process when the urgency for new compounds is higher than ever.
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Affiliation(s)
- Sergio Antoraz
- Departamento de Microbiología y Genética, Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas, Universidad de Salamanca Salamanca, Spain
| | - Ramón I Santamaría
- Departamento de Microbiología y Genética, Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas, Universidad de Salamanca Salamanca, Spain
| | - Margarita Díaz
- Departamento de Microbiología y Genética, Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas, Universidad de Salamanca Salamanca, Spain
| | - David Sanz
- Departamento de Microbiología y Genética, Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas, Universidad de Salamanca Salamanca, Spain
| | - Héctor Rodríguez
- Departamento de Microbiología y Genética, Instituto de Biología Funcional y Genómica, Consejo Superior de Investigaciones Científicas, Universidad de Salamanca Salamanca, Spain
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Tan GY, Peng Y, Lu C, Bai L, Zhong JJ. Engineering validamycin production by tandem deletion of γ-butyrolactone receptor genes in Streptomyces hygroscopicus 5008. Metab Eng 2015; 28:74-81. [DOI: 10.1016/j.ymben.2014.12.003] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2014] [Revised: 10/31/2014] [Accepted: 12/08/2014] [Indexed: 11/29/2022]
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Qu S, Kang Q, Wu H, Wang L, Bai L. Positive and negative regulation of GlnR in validamycin A biosynthesis by binding to different loci in promoter region. Appl Microbiol Biotechnol 2015; 99:4771-83. [PMID: 25672849 DOI: 10.1007/s00253-015-6437-0] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2014] [Revised: 01/22/2015] [Accepted: 01/25/2015] [Indexed: 12/27/2022]
Abstract
Validamycin A (VAL-A) is a C7N aminocyclitol antibiotic produced by Streptomyces hygroscopicus var. jinggangensis 5008, which has been widely used as antifungal agent against rice sheath blight disease. VAL-A biosynthesis has been proven to be affected by γ-butyrolactone and temperature. Herein, we showed that GlnR, a global regulator in nitrogen metabolism, is specifically associated with valK-valA intergenic promoter region by DNA-affinity chromatography and MS-based protein identification. Subsequent EMSA and DNase I footprinting assays revealed two GlnR binding sites in this promoter region. Targeted disruption of glnR in S. hygroscopicus 5008 led to a significant increase in the transcription of VAL-A structural genes, albeit the VAL-A production was reduced by 80 % and the sporulation of the mutant was impaired. Compared with the wild-type 5008, site-specific mutagenesis of GlnR binding site I enhanced VAL-A production by 2.5-fold, whereas the mutation of GlnR binding site II resulted in a 50 % reduction of VAL-A yield. Moreover, tandem mutation of site I in the site II mutant led to a 66 % increase of VAL-A production. The result suggested that GlnR not only serves as an inhibitor by binding site I but also as an activator by binding site II for VAL-A biosynthesis. Furthermore, overexpression of glnR in the site I mutant JG45 improved VAL-A production for 41 % compared with the control strain containing the vector. Therefore, the obtained data illustrate a novel regulatory feature of the global regulator GlnR. GlnR is firstly proved to act simultaneously as an activator and a repressor in validamycin biosynthesis by binding to different loci within a promoter region of the gene cluster.
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Affiliation(s)
- Shuang Qu
- State Key Laboratory of Microbial Metabolism and School of Life Sciences and Biotechnology, Shanghai Jiao Tong University, Shanghai, 200240, China
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28
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Chen C, Zhao X, Chen L, Jin Y, Zhao ZK, Suh JW. Effect of overexpression of endogenous and exogenous Streptomyces antibiotic regulatory proteins on tacrolimus (FK506) production in Streptomyces sp. KCCM11116P. RSC Adv 2015. [DOI: 10.1039/c4ra15038d] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Overexpression of SARPs enhanced FK506 production in Streptomyces sp. KCCM1116P. The endogenous SARPs improved production titer, whereas the exogenous SARP enhanced productivity at the early fermentation stage.
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Affiliation(s)
- Chao Chen
- School of Life Science and Biotechnology
- Dalian University of Technology
- Dalian 116024
- China
| | - Xinqing Zhao
- School of Life Science and Biotechnology
- Dalian University of Technology
- Dalian 116024
- China
- School of Life Science and Biotechnology
| | - Liangyu Chen
- School of Life Science and Biotechnology
- Dalian University of Technology
- Dalian 116024
- China
| | - Yingyu Jin
- Division of Bioscience and Bioinformatics
- Myongji University
- Yongin 449-728
- South Korea
| | - Zongbao K. Zhao
- Department of Biotechnology
- Dalian Institute of Chemical Physics
- Chinese Academy of Sciences
- Dalian 116023
- China
| | - Joo-Won Suh
- Division of Bioscience and Bioinformatics
- Myongji University
- Yongin 449-728
- South Korea
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Enhanced production of validamycin A in Streptomyces hygroscopicus 5008 by engineering validamycin biosynthetic gene cluster. Appl Microbiol Biotechnol 2014; 98:7911-22. [DOI: 10.1007/s00253-014-5943-9] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2014] [Revised: 06/24/2014] [Accepted: 07/07/2014] [Indexed: 10/25/2022]
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30
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Makitrynskyy R, Ostash B, Tsypik O, Rebets Y, Doud E, Meredith T, Luzhetskyy A, Bechthold A, Walker S, Fedorenko V. Pleiotropic regulatory genes bldA, adpA and absB are implicated in production of phosphoglycolipid antibiotic moenomycin. Open Biol 2013; 3:130121. [PMID: 24153004 PMCID: PMC3814723 DOI: 10.1098/rsob.130121] [Citation(s) in RCA: 46] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
Unlike the majority of actinomycete secondary metabolic pathways, the biosynthesis of peptidoglycan glycosyltransferase inhibitor moenomycin in Streptomyces ghanaensis does not involve any cluster-situated regulators (CSRs). This raises questions about the regulatory signals that initiate and sustain moenomycin production. We now show that three pleiotropic regulatory genes for Streptomyces morphogenesis and antibiotic production—bldA, adpA and absB—exert multi-layered control over moenomycin biosynthesis in native and heterologous producers. The bldA gene for tRNALeuUAA is required for the translation of rare UUA codons within two key moenomycin biosynthetic genes (moe), moeO5 and moeE5. It also indirectly influences moenomycin production by controlling the translation of the UUA-containing adpA and, probably, other as-yet-unknown repressor gene(s). AdpA binds key moe promoters and activates them. Furthermore, AdpA interacts with the bldA promoter, thus impacting translation of bldA-dependent mRNAs—that of adpA and several moe genes. Both adpA expression and moenomycin production are increased in an absB-deficient background, most probably because AbsB normally limits adpA mRNA abundance through ribonucleolytic cleavage. Our work highlights an underappreciated strategy for secondary metabolism regulation, in which the interaction between structural genes and pleiotropic regulators is not mediated by CSRs. This strategy might be relevant for a growing number of CSR-free gene clusters unearthed during actinomycete genome mining.
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Affiliation(s)
- Roman Makitrynskyy
- Department of Genetics and Biotechnology, Ivan Franko National University of Lviv, Hrushevskoho st. 4, Lviv 79005, Ukraine
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