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CRISPR/Cas9-Mediated Multi-Locus Promoter Engineering in ery Cluster to Improve Erythromycin Production in Saccharopolyspora erythraea. Microorganisms 2023; 11:microorganisms11030623. [PMID: 36985197 PMCID: PMC10059589 DOI: 10.3390/microorganisms11030623] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2023] [Revised: 02/10/2023] [Accepted: 02/22/2023] [Indexed: 03/05/2023] Open
Abstract
Erythromycins are a group of macrolide antibiotics produced by Saccharopolyspora erythraea. Erythromycin biosynthesis, which is a long pathway composed of a series of biochemical reactions, is precisely controlled by the type I polyketide synthases and accessary tailoring enzymes encoded by ery cluster. In the previous work, we have characterized that six genes representing extremely low transcription levels, SACE_0716-SACE_0720 and SACE_0731, played important roles in limiting erythromycin biosynthesis in the wild-type strain S. erythraea NRRL 23338. In this study, to relieve the potential bottlenecks of erythromycin biosynthesis, we fine-tuned the expression of each key limiting ery gene by CRISPR/Cas9-mediated multi-locus promoter engineering. The native promoters were replaced with different heterologous ones of various strengths, generating ten engineered strains, whose erythromycin productions were 2.8- to 6.0-fold improved compared with that of the wild-type strain. Additionally, the optimal expression pattern of multiple rate-limiting genes and preferred engineering strategies of each locus for maximizing erythromycin yield were also summarized. Collectively, our work lays a foundation for the overall engineering of ery cluster to further improve erythromycin production. The experience of balancing multiple rate-limiting factors within a cluster is also promising to be applied in other actinomycetes to efficiently produce value-added natural products.
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Wang Q, Zheng H, Tao R, Li Q, Jiang Y, Yang S. Vitreoscilla hemoglobin enhances the catalytic performance of industrial oxidases in vitro. Appl Microbiol Biotechnol 2022; 106:3657-3667. [PMID: 35579683 DOI: 10.1007/s00253-022-11974-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2021] [Revised: 04/23/2022] [Accepted: 04/27/2022] [Indexed: 11/25/2022]
Abstract
Oxidases are a group of oxidoreductases and need molecular oxygen in the catalytic process. Vitreoscilla hemoglobin (VHb) can improve the growth and productivity of host cells under hypoxic conditions, rendering it attractive for industrial application. In this work, we demonstrated the addition of immobilized VHb increased the catalytic activity of immobilized D-amino acid oxidase of Trigonopsis variabilis by two-fold when catalyzing cephalosporin C under oxygen-limited conditions. A similar increase of activities was observed in glucose oxidase, alcohol oxidase, and p-hydroxymandelate synthase by adding free VHb or immobilized VHb under hypoxic conditions. When L-glutamate oxidase was used to catalyze L-glutamate to produce α-ketoglutarate, the yield increased from 80.6 to 96.9% by fusing VHb with L-glutamate oxidase. Results demonstrated that the addition of free VHb, immobilized VHb, or fused VHb could increase the catalytic efficiency of oxidases, which was considered by increasing the concentration of the microenvironmental oxygen. Thus, VHb may become a potential additive agent to promote the efficiency of oxidases on industrial scale . KEY POINTS: • First time confirmation of facilitation of VHb on several industrial oxidases in vitro • VHb functions under hypoxic conditions rather than oxygen-enriched conditions • VHb functions in vitro in the form of free, immobilized protein and fusion enzyme.
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Affiliation(s)
- Qingzhuo Wang
- School of Food Science and Pharmaceutical Engineering, Nanjing Normal University, Nanjing, 210000, China.,CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China
| | - Huabao Zheng
- State Key Laboratory of Subtropical Silviculture, College of Environmental and Resource Sciences, Zhejiang A & F University, Hangzhou, 311300, China
| | - Rongsheng Tao
- Huzhou Center of Industrial Biotechnology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Huzhou, 313000, China.,Huzhou Yisheng Biotechnology Co., Ltd, Huzhou, 313000, China
| | - Qi Li
- College of Life Sciences, Sichuan Normal University, Chengdu, 610101, China
| | - Yu Jiang
- Huzhou Center of Industrial Biotechnology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Huzhou, 313000, China. .,Shanghai Taoyusheng Biotechnology Co., Ltd, Shanghai, 200000, China.
| | - Sheng Yang
- CAS Center for Excellence in Molecular Plant Sciences, Chinese Academy of Sciences, Shanghai, 200032, China. .,Huzhou Center of Industrial Biotechnology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Huzhou, 313000, China.
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Wang ZK, Gong JS, Qin J, Li H, Lu ZM, Shi JS, Xu ZH. Improving the Intensity of Integrated Expression for Microbial Production. ACS Synth Biol 2021; 10:2796-2807. [PMID: 34738786 DOI: 10.1021/acssynbio.1c00334] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/24/2023]
Abstract
Chromosomal integration of exogenous genes is preferred for industrially related fermentation, as plasmid-mediated fermentation leads to extra metabolic burden and genetic instability. Moreover, with the development and advancement of genome engineering and gene editing technologies, inserting genes into chromosomes has become more convenient; integration expression is extensively utilized in microorganisms for industrial bioproduction and expected to become the trend of recombinant protein expression. However, in actual research and application, it is important to enhance the expression of heterologous genes at the host genome level. Herein, we summarized the basic principles and characteristics of genomic integration; furthermore, we highlighted strategies to improve the expression of chromosomal integration of genes and pathways in host strains from three aspects, including chassis cell optimization, regulation of expression elements in gene expression cassettes, optimization of gene dose level and integration sites on chromosomes. Moreover, we reviewed and summarized the relevant studies on the application of integrated expression in the exploration of gene function and the various types of industrial microorganism production. Consequently, this review would serve as a reference for the better application of integrated expression.
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Affiliation(s)
- Zi-Kai Wang
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Gong
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Jiufu Qin
- Science Center for Future Foods, Jiangnan University, Wuxi 214122, PR China
| | - Hui Li
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Zhen-Ming Lu
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
| | - Jin-Song Shi
- Key Laboratory of Carbohydrate Chemistry and Biotechnology, Ministry of Education, School of Pharmaceutical Sciences, Jiangnan University, Wuxi 214122, PR China
| | - Zheng-Hong Xu
- National Engineering Laboratory for Cereal Fermentation Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, PR China
- Jiangsu Provincial Research Center for Bioactive Product Processing Technology, Jiangnan University, Wuxi 214122, PR China
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4
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Huang K, Zhang B, Shen ZY, Cai X, Liu ZQ, Zheng YG. Enhanced amphotericin B production by genetically engineered Streptomyces nodosus. Microbiol Res 2020; 242:126623. [PMID: 33189073 DOI: 10.1016/j.micres.2020.126623] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/29/2020] [Revised: 09/08/2020] [Accepted: 10/09/2020] [Indexed: 11/26/2022]
Abstract
The antifungal agent amphotericin B (AmB) is a polyketide produced by Streptomyces nodosus. The synthetic precursors of the amphotericin macrolactone skeleton are acetyl-CoA, malonyl-CoA and methylmalonyl-CoA. The genome sequence of the wild type S. nodosus ATCC14899 revealed a type II polyketide synthase (PKS) competing for malonyl-CoA. The same competitive branch was sequenced and verified in a mutant named S. nodosus ZJB2016050 (S. nodosus N3) screened in our lab. The transcriptome of the secondary metabolic synthetic gene cluster comparisons suggested that type II PKS (PKS5) competition is a factor in low production. The deletion of the PKS5 gene led to the titer of AmB improved from 5.01 g/L to 6.32 g/L while the by-product amphotericin A (AmA) reduced from 0.51 g/L to 0.12 g/L. A sequence of genes including PKS amphA, acc1, mme and mcm were overexpressed in a ΔPKS5 mutant, resulting in improved production AmB from 5.01 g/L to 7.06 g/L in shake flasks at 96 h. The yield of AmB and AmA in a 5 L bioreactor at 144 h was 15.6 g/L and 0.36 g/L, respectively. The intracellular reducibility of the wild type, mutagenesis type and genetically engineered type were detected, which was first found to be related to the by-product AmA. The increment of skeleton biosynthesis may consume more NADPH and reduces AmphC ER5 domain reduction. This study can be implemented for other polyketides in industrial production.
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Affiliation(s)
- Kai Huang
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, 310014, PR China; Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, PR China
| | - Bo Zhang
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, 310014, PR China; Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, PR China
| | - Zhen-Yang Shen
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, 310014, PR China; Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, PR China
| | - Xue Cai
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, 310014, PR China; Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, PR China
| | - Zhi-Qiang Liu
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, 310014, PR China; Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, PR China.
| | - Yu-Guo Zheng
- The National and Local Joint Engineering Research Center for Biomanufacturing of Chiral Chemicals, Zhejiang University of Technology, Hangzhou, 310014, PR China; Key Laboratory of Bioorganic Synthesis of Zhejiang Province, College of Biotechnology and Bioengineering, Zhejiang University of Technology, Hangzhou, 310014, PR China
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5
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Sayed A, Abdel‐Wahab N, Hassan H, Abdelmohsen U. Saccharopolyspora
: an underexplored source for bioactive natural products. J Appl Microbiol 2019; 128:314-329. [DOI: 10.1111/jam.14360] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2019] [Revised: 05/19/2019] [Accepted: 06/12/2019] [Indexed: 11/27/2022]
Affiliation(s)
- A.M. Sayed
- Department of Pharmacognosy, Faculty of Pharmacy Nahda University Beni‐Suef Egypt
| | - N.M. Abdel‐Wahab
- Department of Pharmacognosy, Faculty of Pharmacy Minia University Minia Egypt
| | - H.M. Hassan
- Department of Pharmacognosy, Faculty of Pharmacy Beni‐Suef University Beni‐Suef Egypt
| | - U.R. Abdelmohsen
- Department of Pharmacognosy, Faculty of Pharmacy Minia University Minia Egypt
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6
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Chen C, Hong M, Chu J, Huang M, Ouyang L, Tian X, Zhuang Y. Blocking the flow of propionate into TCA cycle through a mutB knockout leads to a significant increase of erythromycin production by an industrial strain of Saccharopolyspora erythraea. Bioprocess Biosyst Eng 2016; 40:201-209. [DOI: 10.1007/s00449-016-1687-5] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/13/2016] [Accepted: 09/23/2016] [Indexed: 11/28/2022]
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7
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Mo Q, Zhang H, Liu Q, Tang X, Zhao L, Zan X, Song Y. Enhancing nosiheptide production in Streptomyces actuosus
by heterologous expression of haemoprotein from Sinorhizobium meliloti. Lett Appl Microbiol 2016; 62:480-7. [DOI: 10.1111/lam.12575] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/19/2016] [Revised: 03/30/2016] [Accepted: 04/18/2016] [Indexed: 12/17/2022]
Affiliation(s)
- Q. Mo
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi China
| | - H. Zhang
- Colin Ratledge Center for Microbial Lipids; School of Agricultural Engineering and Food Science; Shandong University of Technology; Zibo China
| | - Q. Liu
- Colin Ratledge Center for Microbial Lipids; School of Agricultural Engineering and Food Science; Shandong University of Technology; Zibo China
| | - X. Tang
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi China
| | - L. Zhao
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi China
| | - X. Zan
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi China
| | - Y. Song
- State Key Laboratory of Food Science and Technology; School of Food Science and Technology; Jiangnan University; Wuxi China
- Colin Ratledge Center for Microbial Lipids; School of Agricultural Engineering and Food Science; Shandong University of Technology; Zibo China
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8
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Wu H, Wang Y, Yuan L, Mao Y, Wang W, Zhu L, Wu P, Fu C, Müller R, Weaver DT, Zhang L, Zhang B. Inactivation of SACE_3446, a TetR family transcriptional regulator, stimulates erythromycin production in Saccharopolyspora erythraea. Synth Syst Biotechnol 2016; 1:39-46. [PMID: 29062926 PMCID: PMC5640589 DOI: 10.1016/j.synbio.2016.01.004] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2015] [Revised: 01/08/2016] [Accepted: 01/10/2016] [Indexed: 11/29/2022] Open
Abstract
Erythromycin A is a widely used antibiotic produced by Saccharopolyspora erythraea; however, its biosynthetic cluster lacks a regulatory gene, limiting the yield enhancement via regulation engineering of S. erythraea. Herein, six TetR family transcriptional regulators (TFRs) belonging to three genomic context types were individually inactivated in S. erythraea A226, and one of them, SACE_3446, was proved to play a negative role in regulating erythromycin biosynthesis. EMSA and qRT-PCR analysis revealed that SACE_3446 covering intact N-terminal DNA binding domain specifically bound to the promoter regions of erythromycin biosynthetic gene eryAI, the resistant gene ermE and the adjacent gene SACE_3447 (encoding a long-chain fatty-acid CoA ligase), and repressed their transcription. Furthermore, we explored the interaction relationships of SACE_3446 and previously identified TFRs (SACE_3986 and SACE_7301) associated with erythromycin production. Given demonstrated relatively independent regulation mode of SACE_3446 and SACE_3986 in erythromycin biosynthesis, we individually and concomitantly inactivated them in an industrial S. erythraea WB. Compared with WB, the WBΔ3446 and WBΔ3446Δ3986 mutants respectively displayed 36% and 65% yield enhancement of erythromycin A, following significantly elevated transcription of eryAI and ermE. When cultured in a 5 L fermentor, erythromycin A of WBΔ3446 and WBΔ3446Δ3986 successively reached 4095 mg/L and 4670 mg/L with 23% and 41% production improvement relative to WB. The strategy reported here will be useful to improve antibiotics production in other industrial actinomycete.
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Affiliation(s)
- Hang Wu
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
| | - Yansheng Wang
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
| | - Li Yuan
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
| | - Yongrong Mao
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
| | - Weiwei Wang
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
| | - Lin Zhu
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
| | - Panpan Wu
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
| | - Chengzhang Fu
- CAS Key Laboratory of Pathogenic Microbiology & Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China.,Helmholtz Institute for Pharmaceutical Research, Helmholtz Centre for Infection Research and Department of Pharmaceutical Biotechnology, Saarland University, P.O. Box 15115, 66041 Saarbrücken, Germany
| | - Rolf Müller
- Helmholtz Institute for Pharmaceutical Research, Helmholtz Centre for Infection Research and Department of Pharmaceutical Biotechnology, Saarland University, P.O. Box 15115, 66041 Saarbrücken, Germany
| | - David T Weaver
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
| | - Lixin Zhang
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China.,CAS Key Laboratory of Pathogenic Microbiology & Immunology, Institute of Microbiology, Chinese Academy of Sciences, Beijing 100101, China
| | - Buchang Zhang
- Institute of Health Sciences, School of Life Sciences, Anhui University, Hefei 230601, China
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9
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van Dissel D, Claessen D, van Wezel GP. Morphogenesis of Streptomyces in submerged cultures. ADVANCES IN APPLIED MICROBIOLOGY 2014; 89:1-45. [PMID: 25131399 DOI: 10.1016/b978-0-12-800259-9.00001-9] [Citation(s) in RCA: 58] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
Members of the genus Streptomyces are mycelial bacteria that undergo a complex multicellular life cycle and propagate via sporulation. Streptomycetes are important industrial microorganisms, as they produce a plethora of medically relevant natural products, including the majority of clinically important antibiotics, as well as a wide range of enzymes with industrial application. While development of Streptomyces in surface-grown cultures is well studied, relatively little is known of the parameters that determine morphogenesis in submerged cultures. Here, growth is characterized by the formation of mycelial networks and pellets. From the perspective of industrial fermentations, such mycelial growth is unattractive, as it is associated with slow growth, heterogeneous cultures, and high viscosity. Here, we review the current insights into the genetic and environmental factors that determine mycelial growth and morphology in liquid-grown cultures. The genetic factors include cell-matrix proteins and extracellular polymers, morphoproteins with specific roles in liquid-culture morphogenesis, with the SsgA-like proteins as well-studied examples, and programmed cell death. Environmental factors refer in particular to those dictated by process engineering, such as growth media and reactor set-up. These insights are then integrated to provide perspectives as to how this knowledge can be applied to improve streptomycetes for industrial applications.
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Affiliation(s)
- Dino van Dissel
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands
| | - Dennis Claessen
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands.
| | - Gilles P van Wezel
- Molecular Biotechnology, Institute Biology Leiden, Leiden University, Leiden, The Netherlands.
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10
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Wu P, Pan H, Zhang C, Wu H, Yuan L, Huang X, Zhou Y, Ye BC, Weaver DT, Zhang L, Zhang B. SACE_3986, a TetR family transcriptional regulator, negatively controls erythromycin biosynthesis in Saccharopolyspora erythraea. ACTA ACUST UNITED AC 2014; 41:1159-67. [DOI: 10.1007/s10295-014-1449-9] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2014] [Accepted: 04/17/2014] [Indexed: 11/29/2022]
Abstract
Abstract
Erythromycin, a medically important antibiotic, is produced by Saccharopolyspora erythraea. Unusually, the erythromycin biosynthetic gene cluster lacks a regulatory gene, and the regulation of its biosynthesis remains largely unknown. In this study, through gene deletion, complementation and overexpression experiments, we identified a novel TetR family transcriptional regulator SACE_3986 negatively regulating erythromycin biosynthesis in S. erythraea A226. When SACE_3986 was further inactivated in an industrial strain WB, erythromycin A yield of the mutant was increased by 54.2 % in average compared with that of its parent strain, displaying the universality of SACE_3986 as a repressor for erythromycin production in S. erythraea. qRT-PCR analysis indicated that SACE_3986 repressed the transcription of its adjacent gene SACE_3985 (which encodes a short-chain dehydrogenase/reductase), erythromycin biosynthetic gene eryAI and the resistance gene ermE. As determined by EMSA analysis, purified SACE_3986 protein specifically bound to the intergenic region between SACE_3985 and SACE_3986, whereas it did not bind to the promoter regions of eryAI and ermE. Furthermore, overexpression of SACE_3985 in A226 led to enhanced erythromycin A yield by at least 32.6 %. These findings indicate that SACE_3986 is a negative regulator of erythromycin biosynthesis, and the adjacent gene SACE_3985 is one of its target genes. The present study provides a basis to increase erythromycin production by engineering of SACE_3986 and SACE_3985 in S. erythraea.
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Affiliation(s)
- Panpan Wu
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
| | - Hui Pan
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
| | - Congming Zhang
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
| | - Hang Wu
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
| | - Li Yuan
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
| | - Xunduan Huang
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
| | - Ying Zhou
- grid.28056.39 0000000121634895 State Key Laboratory of Bioreactor Engineering East China University of Science and Technology 200237 Shanghai China
| | - Bang-ce Ye
- grid.28056.39 0000000121634895 State Key Laboratory of Bioreactor Engineering East China University of Science and Technology 200237 Shanghai China
| | - David T Weaver
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
| | - Lixin Zhang
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
- grid.9227.e 0000000119573309 CAS Key Laboratory of Pathogenic Microbiology and Immunology, Institute of Microbiology Chinese Academy of Sciences 100101 Beijing China
| | - Buchang Zhang
- grid.252245.6 0000000100854987 Institute of Health Sciences, School of Life Sciences Anhui University Hefei 230601 China
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11
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Kirm B, Magdevska V, Tome M, Horvat M, Karničar K, Petek M, Vidmar R, Baebler S, Jamnik P, Fujs Š, Horvat J, Fonovič M, Turk B, Gruden K, Petković H, Kosec G. SACE_5599, a putative regulatory protein, is involved in morphological differentiation and erythromycin production in Saccharopolyspora erythraea. Microb Cell Fact 2013; 12:126. [PMID: 24341557 PMCID: PMC3878487 DOI: 10.1186/1475-2859-12-126] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2013] [Accepted: 12/10/2013] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND Erythromycin is a medically important antibiotic, biosynthesized by the actinomycete Saccharopolyspora erythraea. Genes encoding erythromycin biosynthesis are organized in a gene cluster, spanning over 60 kbp of DNA. Most often, gene clusters encoding biosynthesis of secondary metabolites contain regulatory genes. In contrast, the erythromycin gene cluster does not contain regulatory genes and regulation of its biosynthesis has therefore remained poorly understood, which has for a long time limited genetic engineering approaches for erythromycin yield improvement. RESULTS We used a comparative proteomic approach to screen for potential regulatory proteins involved in erythromycin biosynthesis. We have identified a putative regulatory protein SACE_5599 which shows significantly higher levels of expression in an erythromycin high-producing strain, compared to the wild type S. erythraea strain. SACE_5599 is a member of an uncharacterized family of putative regulatory genes, located in several actinomycete biosynthetic gene clusters. Importantly, increased expression of SACE_5599 was observed in the complex fermentation medium and at controlled bioprocess conditions, simulating a high-yield industrial fermentation process in the bioreactor. Inactivation of SACE_5599 in the high-producing strain significantly reduced erythromycin yield, in addition to drastically decreasing sporulation intensity of the SACE_5599-inactivated strains when cultivated on ABSM4 agar medium. In contrast, constitutive overexpression of SACE_5599 in the wild type NRRL23338 strain resulted in an increase of erythromycin yield by 32%. Similar yield increase was also observed when we overexpressed the bldD gene, a previously identified regulator of erythromycin biosynthesis, thereby for the first time revealing its potential for improving erythromycin biosynthesis. CONCLUSIONS SACE_5599 is the second putative regulatory gene to be identified in S. erythraea which has positive influence on erythromycin yield. Like bldD, SACE_5599 is involved in morphological development of S. erythraea, suggesting a very close relationship between secondary metabolite biosynthesis and morphological differentiation in this organism. While the mode of action of SACE_5599 remains to be elucidated, the manipulation of this gene clearly shows potential for improvement of erythromycin production in S. erythraea in industrial setting. We have also demonstrated the applicability of the comparative proteomics approach for identifying new regulatory elements involved in biosynthesis of secondary metabolites in industrial conditions.
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Affiliation(s)
| | | | | | | | | | | | | | | | | | | | | | | | | | | | - Hrvoje Petković
- Acies Bio, d,o,o, Tehnološki park 21, SI-1000, Ljubljana, Slovenia.
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12
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Overview of regulatory strategies and molecular elements in metabolic engineering of bacteria. Mol Biotechnol 2013; 52:300-8. [PMID: 22359157 DOI: 10.1007/s12033-012-9514-y] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
From a viewpoint of biotechnology, metabolic engineering mainly aims to change the natural status of a pathway in a microorganism towards the overproduction of certain bioproducts. The biochemical nature of a pathway implies us that changed pathway is often the collective results of altered behavior of the metabolic enzymes encoded by corresponding genes. By finely modulating the expression of these genes or the properties of the enzyme, we can gain efficient control on the pathway. In this article, we reviewed the typical methods that have been applied to regulate the expression of genes in metabolic engineering. These methods are grouped according to the operation targets in a typical gene. The transcription of a gene is controlled by an indispensable promoter. By utilizing promoters with different strengths, expected levels of expression can be easily achieved, and screening a promoter library may find suitable mutant promoters that can provide tunable expression of a gene. Auto-responsive promoter (quorum sensing (QS)-based or oxygen-inducible) simplifies the induction process by driving the expression of a gene in an automated manner. Light responsive promoter enables reversible and noninvasive control on gene activity, providing a promising method in controlling gene expression with time and space resolution in metabolic engineering involving complicated genetic circuits. Through directed evolution and/or rational design, the encoding sequences of a gene can be altered, leading to the possibly most profound changes in properties of a metabolic enzyme. Introducing an engineered riboswitch in mRNA can make it a regulatory molecule at the same time; ribosomal binding site is commonly engineered to be more attractive for a ribosome through design. Terminator of a gene will affect the stability of an mRNA, and intergenic region will influence the expression of many related genes. Improving the performance of these elements are generally the main activities in metabolic engineering.
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Controlling the feed rate of glucose and propanol for the enhancement of erythromycin production and exploration of propanol metabolism fate by quantitative metabolic flux analysis. Bioprocess Biosyst Eng 2013; 36:1445-53. [PMID: 23361182 DOI: 10.1007/s00449-013-0883-9] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/06/2012] [Accepted: 01/04/2013] [Indexed: 10/27/2022]
Abstract
In this paper, several different fermentation experiments were designed to address whether modulating glucose and propanol feeds could benefit the production level of erythromycin during pilot plant (30 L) fermentation. Results showed that glucose feed rate (determined by a set high or low culture pH) had no effect on erythromycin production, indicating that glucose was not the limiting factor for erythromycin biosynthesis under these conditions. It was found that decreasing glucose feed could stimulate the consumption of propanol, and the high erythromycin production (12.49 ± 0.50 mg ml⁻¹) was achieved by controlling the feed rates of glucose and propanol. The quantitative metabolic flux analysis disclosed that high propanol consumption increased the pool size of propionyl-CoA (~2.147 mmol g⁻¹ day⁻¹) and methylmalonyl-CoA (~1.708 mmol g⁻¹ day⁻¹). It was also found that 45-77 % of the propanol went into the TCA cycle which strengthened the conclusion that blocking the propionate pathway to TCA cycle could lead to a significant increase in erythromycin production in carbohydrate-based media (Reeves et al. Ind Microbiol Biotechnol 7:600-609, 2006). In addition, the results also suggested that a relative low intracellular ATP level resulting from low glucose feed did not limit the erythromycin biosynthesis, and a relatively high NADPH should be beneficial for erythromycin biosynthesis.
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Jiang M, Zhang H, Pfeifer BA. The logic, experimental steps, and potential of heterologous natural product biosynthesis featuring the complex antibiotic erythromycin A produced through E. coli. J Vis Exp 2013:e4346. [PMID: 23354010 DOI: 10.3791/4346] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/07/2023] Open
Abstract
The heterologous production of complex natural products is an approach designed to address current limitations and future possibilities. It is particularly useful for those compounds which possess therapeutic value but cannot be sufficiently produced or would benefit from an improved form of production. The experimental procedures involved can be subdivided into three components: 1) genetic transfer; 2) heterologous reconstitution; and 3) product analysis. Each experimental component is under continual optimization to meet the challenges and anticipate the opportunities associated with this emerging approach. Heterologous biosynthesis begins with the identification of a genetic sequence responsible for a valuable natural product. Transferring this sequence to a heterologous host is complicated by the biosynthetic pathway complexity responsible for product formation. The antibiotic erythromycin A is a good example. Twenty genes (totaling >50 kb) are required for eventual biosynthesis. In addition, three of these genes encode megasynthases, multi-domain enzymes each ~300 kDa in size. This genetic material must be designed and transferred to E. coli for reconstituted biosynthesis. The use of PCR isolation, operon construction, multi-cystronic plasmids, and electro-transformation will be described in transferring the erythromycin A genetic cluster to E. coli. Once transferred, the E. coli cell must support eventual biosynthesis. This process is also challenging given the substantial differences between E. coli and most original hosts responsible for complex natural product formation. The cell must provide necessary substrates to support biosynthesis and coordinately express the transferred genetic cluster to produce active enzymes. In the case of erythromycin A, the E. coli cell had to be engineered to provide the two precursors (propionyl-CoA and (2S)-methylmalonyl-CoA) required for biosynthesis. In addition, gene sequence modifications, plasmid copy number, chaperonin co-expression, post-translational enzymatic modification, and process temperature were also required to allow final erythromycin A formation. Finally, successful production must be assessed. For the erythromycin A case, we will present two methods. The first is liquid chromatography-mass spectrometry (LC-MS) to confirm and quantify production. The bioactivity of erythromycin A will also be confirmed through use of a bioassay in which the antibiotic activity is tested against Bacillus subtilis. The assessment assays establish erythromycin A biosynthesis from E. coli and set the stage for future engineering efforts to improve or diversify production and for the production of new complex natural compounds using this approach.
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Affiliation(s)
- Ming Jiang
- Chemical and Biological Engineering Department, State University of New York at Buffalo, USA
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Luo Y, Kou X, Ding X, Hu S, Tang Y, Li W, Huang F, Yang Q, Chen H, Xia L. Promotion of spinosad biosynthesis by chromosomal integration of the Vitreoscilla hemoglobin gene in Saccharopolyspora spinosa. SCIENCE CHINA-LIFE SCIENCES 2012; 55:172-80. [PMID: 22415689 DOI: 10.1007/s11427-012-4276-0] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/18/2011] [Accepted: 12/05/2011] [Indexed: 11/28/2022]
Abstract
To promote spinosad biosynthesis by improving the limited oxygen supply during high-density fermentation of Saccharopolyspora spinosa, the open reading frame of the Vitreoscilla hemoglobin gene was placed under the control of the promoter for the erythromycin resistance gene by splicing using overlapping extension PCR. This was cloned into the integrating vector pSET152, yielding the Vitreoscilla hemoglobin gene expression plasmid pSET152EVHB. This was then introduced into S. spinosa SP06081 by conjugal transfer, and integrated into the chromosome by site-specific recombination at the integration site ΦC31 on pSET152EVHB. The resultant conjugant, S. spinosa S078-1101, was genetically stable. The integration was further confirmed by PCR and Southern blotting analysis. A carbon monoxide differential spectrum assay showed that active Vitreoscilla hemoglobin was successfully expressed in S. spinosa S078-1101. Fermentation results revealed that expression of the Vitreoscilla hemoglobin gene significantly promoted spinosad biosynthesis under normal oxygen and moderately oxygen-limiting conditions (P<0.01). These findings demonstrate that integrating expression of the Vitreoscilla hemoglobin gene improves oxygen uptake and is an effective means for the genetic improvement of S. spinosa fermentation.
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Affiliation(s)
- Yushuang Luo
- State Key Laboratory of Breeding Base of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha 410081, China
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16
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Enhancing macrolide production in Streptomyces by coexpressing three heterologous genes. Enzyme Microb Technol 2012; 50:5-9. [DOI: 10.1016/j.enzmictec.2011.09.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2011] [Revised: 09/28/2011] [Accepted: 09/28/2011] [Indexed: 11/19/2022]
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Zhang H, Skalina K, Jiang M, Pfeifer BA. Improved E. coli erythromycin a production through the application of metabolic and bioprocess engineering. Biotechnol Prog 2011; 28:292-6. [DOI: 10.1002/btpr.702] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2011] [Revised: 07/30/2011] [Indexed: 11/08/2022]
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Toward improvement of erythromycin A production in an industrial Saccharopolyspora erythraea strain via facilitation of genetic manipulation with an artificial attB site for specific recombination. Appl Environ Microbiol 2011; 77:7508-16. [PMID: 21841022 DOI: 10.1128/aem.06034-11] [Citation(s) in RCA: 32] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Large-scale production of erythromycin A (Er-A) relies on the organism Saccharopolyspora erythraea, in which lack of a typical attB site largely impedes the application of phage ΦC31 integrase-mediated recombination into site-specific engineering. We herein report construction of an artificial attB site in an industrial S. erythraea strain, HL3168 E3, in an effort to break the bottleneck previously encountered during genetic manipulation mainly from homologous or unpredictable nonspecific integration. Replacement of a cryptic gene, nrps1-1, with a cassette containing eight attB DNA sequences did not affect the high Er-producing ability, setting the stage for precisely engineering the industrial Er-producing strain for foreign DNA introduction with a reliable conjugation frequency. Transfer of either exogenous or endogenous genes of importance to Er-A biosynthesis, including the S-adenosylmethionine synthetase gene for positive regulation, vhb for increasing the oxygen supply, and two tailoring genes, eryK and eryG, for optimizing the biotransformation at the late stage, was achieved by taking advantage of this facility, allowing systematic improvement of Er-A production as well as elimination of the by-products Er-B and Er-C in fermentation. The strategy developed here can generally be applicable to other strains that lack the attB site.
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Frey AD, Shepherd M, Jokipii-Lukkari S, Häggman H, Kallio PT. The single-domain globin of Vitreoscilla: augmentation of aerobic metabolism for biotechnological applications. Adv Microb Physiol 2011; 58:81-139. [PMID: 21722792 DOI: 10.1016/b978-0-12-381043-4.00003-9] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Extensive studies have revealed that large-scale, high-cell density bioreactor cultivations have significant impact on metabolic networks of oxygen-requiring production organisms. Oxygen transfer problems associated with fluid dynamics and inefficient mixing efficiencies result in oxygen gradients, which lead to reduced performance of the bioprocess, decreased product yields, and increased production costs. These problems can be partially alleviated by improving bioreactor configuration and setting, but significant improvements have been achieved by metabolic engineering methods, especially by heterologously expressing Vitreoscilla hemoglobin (VHb). Vast numbers of studies have been accumulating during the past 20 years showing the applicability of VHb to improve growth and product yields in a variety of industrially significant prokaryotic and eukaryotic hosts. The global view on the metabolism of globin-expressing Escherichia coli cells depicts increased energy generation, higher oxygen uptake rates, and a decrease in fermentative by-product excretion. Transcriptome and metabolic flux analysis clearly demonstrate the multidimensional influence of heterologous VHb on the expression of stationary phase-specific genes and on the regulation of cellular metabolic networks. The exact biochemical mechanisms by which VHb is able to improve the oxygen-limited growth remain poorly understood. The suggested mechanisms propose either the delivery of oxygen to the respiratory chain or the detoxification of reactive nitrogen species for the protection of cytochrome activity. The expression of VHb in E. coli bioreactor cultures is likely to assist bacterial growth through providing an increase in available intracellular oxygen, although to fully understand the exact role of VHb in vivo, further analysis will be required.
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Zhang Q, Wu J, Qian J, Chu J, Zhuang Y, Zhang S, Liu W. Knocking out of tailoring genes eryK and eryG in an industrial erythromycin-producing strain of Saccharopolyspora erythraea leading to overproduction of erythromycin B, C and D at different conversion ratios. Lett Appl Microbiol 2010; 52:129-37. [PMID: 21175699 DOI: 10.1111/j.1472-765x.2010.02973.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
AIMS To overproduce erythromycin C, B or D and evaluate the effect of disruption of tailoring genes eryK and eryG in an industrial erythromycin producer. METHODS AND RESULTS The tailoring genes eryG and eryK were inactivated individually or simultaneously by targeted gene disruption in an industrial strain Saccharopolyspora erythraea HL3168 E3, resulting in the overproduction of erythromycin C (2·48 g l(-1) ), B (1·70 g l(-1) ) or D (2·15 g l(-1) ) in the mutant strain QL-G, QL-K or QL-KG, respectively. Analysis of the erythromycin congeners throughout the fermentation indicated that, at the end of fermentation, comparatively large amount of erythromycin D (0·67 g l(-1) ) was accumulated in QL-G, whereas only small amount of erythromycin D (0·10 g l(-1) ) was produced in QL-K. CONCLUSIONS Inactivation of tailoring genes eryG and eryK in the high producer did not affect the biosynthesis of erythromycin. However, erythromycin D could be more efficiently methylated by EryG than be hydroxylated by EryK. SIGNIFICANCE AND IMPACT OF THE STUDY Development of the mutant strains provides a method for the economical large-scale production of potent lead compounds. The information about the accumulation and conversion of erythromycins in the industrial strains may contribute to further improving erythromycin production.
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Affiliation(s)
- Q Zhang
- East China University of Science and Technology, Shanghai, China
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21
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Wu X, Chen Y, Li Y, Li O, Zhu L, Qian C, Tao X, Teng Y. Constitutive expression of Vitreoscilla haemoglobin in Sphingomonas elodea to improve gellan gum production. J Appl Microbiol 2010; 110:422-30. [DOI: 10.1111/j.1365-2672.2010.04896.x] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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22
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Priscila G, Fernández FJ, Absalón AE, Suarez MDR, Sainoz M, Barrios-González J, Mejía A. Expression of the Bacterial Hemoglobin Gene from Vitreoscilla stercoraria Increases Rifamycin B Production in Amycolatopsis mediterranei. J Biosci Bioeng 2008; 106:493-7. [DOI: 10.1263/jbb.106.493] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Accepted: 07/30/2008] [Indexed: 11/17/2022]
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23
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Jung HM, Kim SY, Prabhu P, Moon HJ, Kim IW, Lee JK. Optimization of culture conditions and scale-up to plant scales for teicoplanin production by Actinoplanes teichomyceticus. Appl Microbiol Biotechnol 2008; 80:21-7. [DOI: 10.1007/s00253-008-1530-2] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2008] [Revised: 05/02/2008] [Accepted: 05/05/2008] [Indexed: 11/29/2022]
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Olano C, Lombó F, Méndez C, Salas JA. Improving production of bioactive secondary metabolites in actinomycetes by metabolic engineering. Metab Eng 2008; 10:281-92. [PMID: 18674632 DOI: 10.1016/j.ymben.2008.07.001] [Citation(s) in RCA: 211] [Impact Index Per Article: 13.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2008] [Revised: 07/08/2008] [Accepted: 07/09/2008] [Indexed: 11/25/2022]
Abstract
Production of secondary metabolites is a process influenced by several physico-chemical factors including nutrient supply, oxygenation, temperature and pH. These factors have been traditionally controlled and optimized in industrial fermentations in order to enhance metabolite production. In addition, traditional mutagenesis programs have been used by the pharmaceutical industry for strain and production yield improvement. In the last years, the development of recombinant DNA technology has provided new tools for approaching yields improvement by means of genetic manipulation of biosynthetic pathways. These efforts are usually focused in redirecting precursor metabolic fluxes, deregulation of biosynthetic pathways and overexpression of specific enzymes involved in metabolic bottlenecks. In addition, efforts have been made for the heterologous expression of biosynthetic gene clusters in other organisms, looking not only for an increase of production levels but also to speed the process by using rapidly growing and easy to manipulate organisms compared to the producing organism. In this review, we will focus on these genetic approaches as applied to bioactive secondary metabolites produced by actinomycetes.
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Affiliation(s)
- Carlos Olano
- Departamento de Biología Funcional e Instituto Universitario de Oncología del Principado de Asturias (IUOPA), Universidad de Oviedo, 33006 Oviedo, Spain
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Genetic modulation of the overexpression of tailoring genes eryK and eryG leading to the improvement of erythromycin A purity and production in Saccharopolyspora erythraea fermentation. Appl Environ Microbiol 2008; 74:1820-8. [PMID: 18223111 DOI: 10.1128/aem.02770-07] [Citation(s) in RCA: 59] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Erythromycin A (Er-A) is the most potent and clinically important member in the Er family produced by Saccharopolyspora erythraea. Er-B and Er-C, which are biologically much less active and cause greater side effects than Er-A, serve as the intermediates for Er-A biosynthesis and impurities in fermentation processes of many industrial strains. In this study, systematical modulation of the amounts of tailoring enzymes EryK (a P450 hydroxylase) and EryG (an S-adenosylmethionine-dependent O-methyltransferase) was carried out by genetic engineering in S. erythraea, including alterations of gene copy number ratio and organization and integrating the locus on the chromosome by homologous recombination. Introduction of additional eryK and eryG genes into S. erythraea showed significant impacts on their transcription levels and enhanced the biotransformation process from Er-D to Er-A with gene dose effects. At the eryK/eryG copy number ratio of 3:2 as well as their resultant transcript ratio of around 2.5:1 to 3.0:1, Er-B and Er-C were nearly completely eliminated and accordingly converted to Er-A, and the Er titer was improved by around 25% in the recombinant strain ZL1004 (genotype PermK*-K-K-G + PermE*-K + PermA*-G) and ZL1007 (genotype PermK*-K-G-K + PermE*-K + PermA*-G). This study may contribute to the continuous efforts toward further evaluation of the Er-producing system, with the aims of improving Er-A purity and production at the fermentation stage and lowering the production costs and environmental concerns in industry.
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Kallio PT, Bollinger CJ, Koskenkorva T, Frey AD. Assessment of Biotechnologically Relevant Characteristics of Heterologous Hemoglobins in E. coli. Methods Enzymol 2008; 436:255-72. [DOI: 10.1016/s0076-6879(08)36014-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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Demain AL, Adrio JL. Strain improvement for production of pharmaceuticals and other microbial metabolites by fermentation. PROGRESS IN DRUG RESEARCH. FORTSCHRITTE DER ARZNEIMITTELFORSCHUNG. PROGRES DES RECHERCHES PHARMACEUTIQUES 2008; 65:251-289. [PMID: 18084918 DOI: 10.1007/978-3-7643-8117-2_7] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2023]
Abstract
Microbes have been good to us. They have given us thousands of valuable products with novel structures and activities. In nature, they only produce tiny amounts of these secondary metabolic products as a matter of survival. Thus, these metabolites are not overproduced in nature, but they must be overproduced in the pharmaceutical industry. Genetic manipulations are used in industry to obtain strains that produce hundreds or thousands of times more than that produced by the originally isolated strain. These strain improvement programs traditionally employ mutagenesis followed by screening or selection; this is known as 'brute-force' technology. Today, they are supplemented by modern strategic technologies developed via advances in molecular biology, recombinant DNA technology, and genetics. The progress in strain improvement has increased fermentation productivity and decreased costs tremendously. These genetic programs also serve other goals such as the elimination of undesirable products or analogs, discovery of new antibiotics, and deciphering of biosynthetic pathways.
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Affiliation(s)
- Arnold L Demain
- Research Institute for Scientists Emeriti (RISE), HS-330, Drew University, Madison, NJ 07940 USA.
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29
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Optimization of culture conditions and scale-up to pilot and plant scales for vancomycin production by Amycolatopsis orientalis. Appl Microbiol Biotechnol 2007; 77:789-95. [DOI: 10.1007/s00253-007-1221-4] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/06/2007] [Revised: 09/19/2007] [Accepted: 09/20/2007] [Indexed: 10/22/2022]
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30
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Reeves AR, Brikun IA, Cernota WH, Leach BI, Gonzalez MC, Weber JM. Engineering of the methylmalonyl-CoA metabolite node of Saccharopolyspora erythraea for increased erythromycin production. Metab Eng 2007; 9:293-303. [PMID: 17482861 PMCID: PMC2722834 DOI: 10.1016/j.ymben.2007.02.001] [Citation(s) in RCA: 63] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2006] [Revised: 01/23/2007] [Accepted: 02/27/2007] [Indexed: 10/23/2022]
Abstract
Engineering of the methylmalonyl-CoA (mmCoA) metabolite node of the Saccharopolyspora erythraea wild-type strain through duplication of the mmCoA mutase (MCM) operon led to a 50% increase in erythromycin production in a high-performance oil-based fermentation medium. The MCM operon was carried on a 6.8kb DNA fragment in a plasmid which was inserted by homologous recombination into the S. erythraea chromosome. The fragment contained one uncharacterized gene, ORF1; three MCM related genes, mutA, mutB, meaB; and one gntR-family regulatory gene, mutR. Additional strains were constructed containing partial duplications of the MCM operon, as well as a knockout of ORF1. None of these strains showed any significant alteration in their erythromycin production profile. The combined results showed that increased erythromycin production only occurred in a strain containing a duplication of the entire MCM operon including mutR and a predicted stem-loop structure overlapping the 3' terminus of the mutR coding sequence.
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Affiliation(s)
- Andrew R Reeves
- Fermalogic Inc. Research and Development, 2201 West Campbell Park Drive, Chicago, IL 60612, US
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31
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Wang Y, Wang Y, Chu J, Zhuang Y, Zhang L, Zhang S. Improved production of erythromycin A by expression of a heterologous gene encoding S-adenosylmethionine synthetase. Appl Microbiol Biotechnol 2007; 75:837-42. [PMID: 17351771 DOI: 10.1007/s00253-007-0894-z] [Citation(s) in RCA: 34] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/10/2007] [Revised: 02/14/2007] [Accepted: 02/16/2007] [Indexed: 11/24/2022]
Abstract
An S-adenosylmethionine synthetase (SAM-s) gene from Streptomyces spectabilis was integrated along with vector DNA into the chromosome of a Saccharopolyspora erythraea E2. Elevated production of SAM was observed in the recombinant strain Saccharopolyspora erythraea E1. The results from the bioassay showed that the titer of erythromycin was increased from 920 IU ml(-1) by E2 to approximately 2,000 IU ml(-1) by E1. High performance liquid chromatography (HPLC) analysis revealed that there was a 132% increase in erythromycin A compared with the original strain, while the erythromycin B, the main impurity component in erythromycin, was decreased by 30%. The sporulation process was inhibited, while the SAM-s gene was expressed. The addition of the exogenous SAM also inhibited sporulation and promoted an increase in erythromycin titers.
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Affiliation(s)
- Yong Wang
- State Key Laboratory of Bioreactor Engineering, East China University of Science and Technology, Shanghai 200237, China.
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32
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Zhang L, Li Y, Wang Z, Xia Y, Chen W, Tang K. Recent developments and future prospects of Vitreoscilla hemoglobin application in metabolic engineering. Biotechnol Adv 2007; 25:123-36. [PMID: 17184955 DOI: 10.1016/j.biotechadv.2006.11.001] [Citation(s) in RCA: 85] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2006] [Revised: 11/02/2006] [Accepted: 11/02/2006] [Indexed: 11/27/2022]
Abstract
In hypoxic conditions, bacteria express a kind of hemoglobin, which is proposed to enhance respiration and energy metabolism by promoting oxygen delivery. Bacteria hemoglobin from Vitreoscilla stercoraria - Vitreoscilla hemoglobin (VHb), when expressed in various hosts in oxygen-limited conditions, has been shown to improve growth, protein secretion, metabolite productivity and stress resistance of hosts, thus rendering the protein promising in metabolic engineering, especially in plant metabolism optimization. In this review, many well-studies areas are presented to illustrate the potential of VHb application in biotechnology industry, to discuss the cellular mechanisms of VHb function and to show the wide variety of approaches taken within the field.
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Affiliation(s)
- Lei Zhang
- State Key Laboratory of Genetic Engineering, School of Life Sciences, Fudan-SJTU-Nottingham Plant Biotechnology R and D Center, Fudan University, Shanghai 200433, PR China
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Rokem JS, Lantz AE, Nielsen J. Systems biology of antibiotic production by microorganisms. Nat Prod Rep 2007; 24:1262-87. [DOI: 10.1039/b617765b] [Citation(s) in RCA: 123] [Impact Index Per Article: 7.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
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Abstract
Although microorganisms are extremely good in presenting us with an amazing array of valuable products, they usually produce them only in amounts that they need for their own benefit; thus, they tend not to overproduce their metabolites. In strain improvement programs, a strain producing a high titer is usually the desired goal. Genetics has had a long history of contributing to the production of microbial products. The tremendous increases in fermentation productivity and the resulting decreases in costs have come about mainly by mutagenesis and screening/selection for higher producing microbial strains and the application of recombinant DNA technology.
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Affiliation(s)
- Jose L Adrio
- Department of Biotechnology, Puleva Biotech, S.A., Granada, Spain.
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35
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Lum AM, Huang J, Hutchinson CR, Kao CM. Reverse engineering of industrial pharmaceutical-producing actinomycete strains using DNA microarrays. Metab Eng 2004; 6:186-96. [PMID: 15256208 DOI: 10.1016/j.ymben.2003.12.001] [Citation(s) in RCA: 53] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2003] [Accepted: 12/17/2003] [Indexed: 11/23/2022]
Abstract
Transcript levels in production cultures of wildtype and classically improved strains of the actinomycete bacteria Saccharopolyspora erythraea and Streptomyces fradiae were monitored using microarrays of the sequenced actinomycete S. coelicolor. Sac. erythraea and S. fradiae synthesize the polyketide antibiotics erythromycin and tylosin, respectively, and the classically improved strains contain unknown overproduction mutations. The Sac. erythraea overproducer was found to express the entire 56-kb erythromycin gene cluster several days longer than the wildtype strain. In contrast, the S. fradiae wildtype and overproducer strains expressed the 85-kb tylosin biosynthetic gene cluster similarly, while they expressed several tens of other S. fradiae genes and S. coelicolor homologs differently, including the acyl-CoA dehydrogenase gene aco and the S. coelicolor isobutyryl-CoA mutase homolog icmA. These observations indicated that overproduction mechanisms in classically improved strains can affect both the timing and rate of antibiotic synthesis, and alter the regulation of antibiotic biosynthetic enzymes and enzymes involved in precursor metabolism.
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Affiliation(s)
- Amy M Lum
- Department of Chemical Engineering, MC 5025, Stanford University, CA 94305, USA
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36
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Frey AD, Kallio PT. Bacterial hemoglobins and flavohemoglobins: versatile proteins and their impact on microbiology and biotechnology. FEMS Microbiol Rev 2003; 27:525-45. [PMID: 14550944 DOI: 10.1016/s0168-6445(03)00056-1] [Citation(s) in RCA: 155] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022] Open
Abstract
In response to oxygen limitation or oxidative and nitrosative stress, bacteria express three kinds of hemoglobin proteins: truncated hemoglobins (tr Hbs), hemoglobins (Hbs) and flavohemoglobins (flavo Hbs). The two latter groups share a high sequence homology and structural similarity in their globin domain. Flavohemoglobin proteins contain an additional reductase domain at their C-terminus and their expression is induced in the presence of reactive nitrogen and oxygen species. Flavohemoglobins detoxify NO in an aerobic process, termed nitric oxide dioxygenase reaction, which protects the host from various noxious nitrogen compounds. Only a small number of bacteria express hemoglobin proteins and the best studied of these is from Vitreoscilla sp. Vitreoscilla hemoglobin (VHb) has been expressed in various heterologous hosts under oxygen-limited conditions and has been shown to improve growth and productivity, rendering the protein interesting for biotechnology industry. The close interaction of VHb with the terminal oxidases has been shown and this interplay has been proposed to enhance respiratory activity and energy production by delivering oxygen, the ultimate result being an improvement in growth properties.
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Affiliation(s)
- Alexander D Frey
- Institute of Biotechnology, ETH Zürich, 8093 Zürich, Switzerland
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Paradkar A, Trefzer A, Chakraburtty R, Stassi D. Streptomyces genetics: a genomic perspective. Crit Rev Biotechnol 2003; 23:1-27. [PMID: 12693442 DOI: 10.1080/713609296] [Citation(s) in RCA: 59] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/23/2022]
Abstract
Streptomycetes are gram-positive, soil-inhabiting bacteria of the order Actinomycetales. These organisms exhibit an unusual, developmentally complex life cycle and produce many economically important secondary metabolites, such as antibiotics, immunosuppressants, insecticides, and anti-tumor agents. Streptomyces species have been the subject of genetic investigation for over 50 years, with many studies focusing on the developmental cycle and the production of secondary metabolites. This information provides a solid foundation for the application of structural and functional genomics to the actinomycetes. The complete DNA sequence of the model organism, Streptomyces coelicolor M145, has been published recently, with others expected to follow soon. As more genomic sequences become available, the rational genetic manipulation of these organisms to elucidate metabolic and regulatory networks, to increase the production of commercially important compounds, and to create novel secondary metabolites will be greatly facilitated. This review presents the current state of the field of genomics as it is being applied to the actinomycetes.
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Affiliation(s)
- Ashish Paradkar
- Small Molecule Discovery, Diversa Corporation, 4955 Directors Place, San Diego, CA 92121, USA
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Vanden Boom TJ. Recent developments in the molecular genetics of the erythromycin-producing organism Saccharopolyspora erythraea. ADVANCES IN APPLIED MICROBIOLOGY 2003; 47:79-111. [PMID: 12876795 DOI: 10.1016/s0065-2164(00)47002-4] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/26/2022]
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Hu Z, Pfeifer BA, Chao E, Murli S, Kealey J, Carney JR, Ashley G, Khosla C, Hutchinson CR. A specific role of the Saccharopolyspora erythraea thioesterase II gene in the function of modular polyketide synthases. MICROBIOLOGY (READING, ENGLAND) 2003; 149:2213-2225. [PMID: 12904561 DOI: 10.1099/mic.0.26015-0] [Citation(s) in RCA: 40] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
Bacterial modular polyketide synthase (PKS) genes are commonly associated with another gene that encodes a thioesterase II (TEII) believed to remove aberrantly loaded substrates from the PKS. Co-expression of the Saccharopolyspora erythraea ery-ORF5 TEII and eryA genes encoding 6-deoxyerythronolide B synthase (DEBS) in Streptomyces hosts eliminated or significantly lowered production of 8,8'-deoxyoleandolide [15-nor-6-deoxyerythronolide B (15-nor-6dEB)], which arises from an acetate instead of a propionate starter unit. Disruption of the TEII gene in an industrial Sac. erythraea strain caused a notable amount of 15-norerythromycins to be produced by utilization of an acetate instead of a propionate starter unit and also resulted in moderately lowered production of erythromycin compared with the amount produced by the parental strain. A similar behaviour of the TEII gene was observed in Escherichia coli strains that produce 6dEB and 15-methyl-6dEB. Direct biochemical analysis showed that the ery-ORF5 TEII enzyme favours hydrolysis of acetyl groups bound to the loading acyl carrier protein domain (ACP(L)) of DEBS. These results point to a clear role of the TEII enzyme, i.e. removal of a specific type of acyl group from the ACP(L) domain of the DEBS1 loading module.
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Affiliation(s)
- Zhihao Hu
- Kosan Biosciences, Hayward, CA 94545, USA
| | - Blaine A Pfeifer
- Department of Chemical Engineering, Chemistry and Biochemistry, Stanford University, Stanford, CA 94305, USA
| | - Elizabeth Chao
- Department of Chemical Engineering, Chemistry and Biochemistry, Stanford University, Stanford, CA 94305, USA
| | | | - Jim Kealey
- Kosan Biosciences, Hayward, CA 94545, USA
| | | | | | - Chaitan Khosla
- Department of Chemical Engineering, Chemistry and Biochemistry, Stanford University, Stanford, CA 94305, USA
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40
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Rodriguez E, Hu Z, Ou S, Volchegursky Y, Hutchinson CR, McDaniel R. Rapid engineering of polyketide overproduction by gene transfer to industrially optimized strains. J Ind Microbiol Biotechnol 2003; 30:480-8. [PMID: 12698320 DOI: 10.1007/s10295-003-0045-1] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2002] [Accepted: 02/24/2003] [Indexed: 01/11/2023]
Abstract
Development of natural products for therapeutic use is often hindered by limited availability of material from producing organisms. The speed at which current technologies enable the cloning, sequencing, and manipulation of secondary metabolite genes for production of novel compounds has made it impractical to optimize each new organism by conventional strain improvement procedures. We have exploited the overproduction properties of two industrial organisms- Saccharopolyspora erythraea and Streptomyces fradiae, previously improved for erythromycin and tylosin production, respectively-to enhance titers of polyketides produced by genetically modified polyketide synthases (PKSs). An efficient method for delivering large PKS expression vectors into S. erythraea was achieved by insertion of a chromosomal attachment site ( attB) for phiC31-based integrating vectors. For both strains, it was discovered that only the native PKS-associated promoter was capable of sustaining high polyketide titers in that strain. Expression of PKS genes cloned from wild-type organisms in the overproduction strains resulted in high polyketide titers whereas expression of the PKS gene from the S. erythraea overproducer in heterologous hosts resulted in only normal titers. This demonstrated that the overproduction characteristics are primarily due to mutations in non-PKS genes and should therefore operate on other PKSs. Expression of genetically engineered erythromycin PKS genes resulted in production of erythromycin analogs in greatly superior quantity than obtained from previously used hosts. Further development of these hosts could bypass tedious mutagenesis and screening approaches to strain improvement and expedite development of compounds from this valuable class of natural products.
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Affiliation(s)
- Eduardo Rodriguez
- Kosan Biosciences Inc, 3832 Bay Center Place, Hayward, CA 94545, USA
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41
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Affiliation(s)
- Martin Fussenegger
- Institute of Biotechnology, Swiss Federal Institute of Technology, ETH Zurich, Switzerland.
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42
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Genetic engineering using fungal flavohemoglobin for constructing Pseudomonas stutzeri strain emitting less nitrous oxide. J Biosci Bioeng 2002. [DOI: 10.1016/s1389-1723(02)80163-3] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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Frey AD, Fiaux J, Szyperski T, Wüthrich K, Bailey JE, Kallio PT. Dissection of central carbon metabolism of hemoglobin-expressing Escherichia coli by 13C nuclear magnetic resonance flux distribution analysis in microaerobic bioprocesses. Appl Environ Microbiol 2001; 67:680-7. [PMID: 11157231 PMCID: PMC92635 DOI: 10.1128/aem.67.2.680-687.2001] [Citation(s) in RCA: 28] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/21/2000] [Accepted: 11/29/2000] [Indexed: 11/20/2022] Open
Abstract
Escherichia coli MG1655 cells expressing Vitreoscilla hemoglobin (VHb), Alcaligenes eutrophus flavohemoprotein (FHP), the N-terminal hemoglobin domain of FHP (FHPg), and a fusion protein which comprises VHb and the A. eutrophus C-terminal reductase domain (VHb-Red) were grown in a microaerobic bioreactor to study the effects of low oxygen concentrations on the central carbon metabolism, using fractional (13)C-labeling of the proteinogenic amino acids and two-dimensional [(13)C, (1)H]-correlation nuclear magnetic resonance (NMR) spectroscopy. The NMR data revealed differences in the intracellular carbon fluxes between E. coli cells expressing either VHb or VHb-Red and cells expressing A. eutrophus FHP or the truncated heme domain (FHPg). E. coli MG1655 cells expressing either VHb or VHb-Red were found to function with a branched tricarboxylic acid (TCA) cycle. Furthermore, cellular demands for ATP and reduction equivalents in VHb- and VHb-Red-expressing cells were met by an increased flux through glycolysis. In contrast, in E. coli cells expressing A. eutrophus hemeproteins, the TCA cycle is running cyclically, indicating a shift towards a more aerobic regulation. Consistently, E. coli cells displaying FHP and FHPg activity showed lower production of the typical anaerobic by-products formate, acetate, and D-lactate. The implications of these observations for biotechnological applications are discussed.
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Affiliation(s)
- A D Frey
- Institute of Biotechnology, ETH Zürich, CH-8093 Zürich, Switzerland
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Dunstan GH, Avignone-Rossa C, Langley D, Bushell ME. The Vancomycin biosynthetic pathway is induced in oxygen-limited Amycolatopsis orientalis (ATCC 19795) cultures that do not produce antibiotic. Enzyme Microb Technol 2000; 27:502-510. [PMID: 10978772 DOI: 10.1016/s0141-0229(00)00238-6] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Vancomycin biosynthetic capacity was stimulated in oxygen-limited bioreactor culture (6.4% DOT) of Amycolatopsis orientalis, coinciding with a down-regulation of the culture growth and protein synthesis rates. However no Vancomycin was detected. ATP production was similar in oxygen-limited and oxygen-sufficient cultures (400-150 µmole(ATP). g(biomass)(-1)). Our findings suggest a critical requirement for oxygen flux through the Vancomycin biosynthetic pathway, which is only met under nutrient-limited conditions in which oxygen is in excess.
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Affiliation(s)
- GH Dunstan
- Microbial Products Laboratory, Biological Sciences, University of Surrey, Guildford, GU2 5x H, Surrey, UK
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Volchegursky Y, Hu Z, Katz L, McDaniel R. Biosynthesis of the anti-parasitic agent megalomicin: transformation of erythromycin to megalomicin in Saccharopolyspora erythraea. Mol Microbiol 2000; 37:752-62. [PMID: 10972798 DOI: 10.1046/j.1365-2958.2000.02059.x] [Citation(s) in RCA: 60] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Megalomicin is a therapeutically diverse compound which possesses antiparasitic, antiviral and antibacterial properties. It is produced by Micromonospora megalomicea and differs from the well-known macrolide antibiotic erythromycin by the addition of a unique deoxyamino sugar, megosamine, to the C-6 hydroxyl. We have cloned and sequenced a 48 kb segment of the megalomicin (meg) biosynthetic gene cluster which contains the modular polyketide synthase (PKS) and the complete pathway for megosamine biosynthesis. The similarities and distinctions between the related megalomicin and erythromycin gene clusters are discussed. Heterologous expression of the megalomicin PKS in Streptomyces lividans led to production of 6-deoxyerythronolide B, the same macrolactone intermediate for erythromycin. A 12 kb fragment harbouring the putative megosamine pathway was expressed in Saccharopolyspora erythraea, resulting in the conversion of erythromycin to megalomicin. Considering the extensive knowledge surrounding the genetic engineering of the erythromycin PKS and the familiarity with genetic manipulation and fermentation of S. erythraea, the ability to produce megalomicin in this strain should allow the engineering of novel megalomicin analogues with potentially improved therapeutic activities.
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