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Li B, Wu C, Bai S, Zhang D, Xu C, Yuan X, Tian J, Bai J, Li L, Fu J. Enhancement of ε-poly-L-lysine production by Streptomyces albulus FQF-24 with feeding strategies using cassava starch as carbon source. Bioprocess Biosyst Eng 2024; 47:1973-1984. [PMID: 39150530 DOI: 10.1007/s00449-024-03078-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Accepted: 08/08/2024] [Indexed: 08/17/2024]
Abstract
ε-Poly-L-lysine (ε-PL) is a natural and wide-spectrum antimicrobial additive. In this study, the production of ε-PL by Streptomyces albulus FQF-24 using cassava starch (CS) as carbon source and the effects of different feeding methods were investigated in a fermenter. The initial shake flask experiments demonstrated the efficient production of ε-PL with CS, achieving the ε-PL production of 1.18 g/L. Subsequent investigations in the fermenter identified that the ideal pH was 3.8 during the ε-PL synthesis phase. Under this condition, the production of ε-PL reached 1.35 g/L. When the pH was maintained at 3.8, the investigation of improvement of feeding composition was carried out in a 5 L fermenter. The intermittent feeding containing CS, inorganic and organic nitrogen sources resulted in the maximum ε-PL production and dry cell weight (DCW) reaching 17.17 g/L and 42.73 g/L. Additionally, continuous feeding with the composition of CS, organic and inorganic nitrogen sources, and inorganic salts further increased ε-PL production and DCW to 27.56 g/L and 38.5 g/L. Summarily, the above results indicate that the fermentation using low-cost CS and continuous feeding strategy with whole medium composition can provide a beneficial reference for the efficient production of ε-PL.
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Affiliation(s)
- Boyan Li
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Chenqi Wu
- Suzhou Polytechnic Institute of Agriculture, Suzhou, 215009, China
| | - Senmeng Bai
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Di Zhang
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Chang Xu
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Xiaofeng Yuan
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Jiayi Tian
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Jing Bai
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Liangzhi Li
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China
| | - Jiaolong Fu
- School of Chemistry and Life Sciences, Suzhou University of Science and Technology, Suzhou, 215009, China.
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2
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Ścigaczewska A, Boruta T, Bizukojć M. Morphological-metabolic analysis in Streptomyces rimosus microparticle-enhanced cultivations (MPEC). Bioprocess Biosyst Eng 2024; 47:891-902. [PMID: 38664238 PMCID: PMC11101530 DOI: 10.1007/s00449-024-03015-2] [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: 09/14/2023] [Accepted: 04/05/2024] [Indexed: 05/19/2024]
Abstract
Streptomyces produce a broad spectrum of biologically active molecules such as oxytetracycline and rimocidin, which are widely used in human and animal treatments. microparticle-enhanced cultivation (MPEC) is one of the tools used for Streptomyces bioprocesses intensification by the control of mycelial morphology. In the present work, morphological changes of Streptomyces rimosus caused by the addition of 10 µm talc microparticles in MPEC were correlated with the biosynthetic activity of the microorganism. Comparing the runs with and without microparticles, major morphological changes were observed in MPEC, including the deformation of pellets, variation of their size, appearance of hyphae and clumps as well as the aggregation of mycelial objects. The presence of talc microparticles also influenced the levels of the studied secondary metabolites produced by S. rimosus. Comparing control and MPEC runs, the addition of talc microparticles increased the amounts of oxytetracycline (9-fold), 2-acetyl-2-decarboxamido-oxytetracycline (7-fold), milbemycin A3+4[O] (3-fold) and CE 108 (1.5-fold), while rimocidin (27-ethyl) and milbemycin β11+4[O] production was reduced. In summary, the addition of talc microparticles to S. rimosus cultivations led to the development of smaller morphological forms like hyphae and clumps as well as to the changes in the amounts of secondary metabolites.
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Affiliation(s)
- Anna Ścigaczewska
- Faculty of Process and Environmental Engineering, Department of Bioprocess Engineering, Lodz University of Technology, ul. Wolczanska 213, 93-005, Lodz, Poland.
| | - Tomasz Boruta
- Faculty of Process and Environmental Engineering, Department of Bioprocess Engineering, Lodz University of Technology, ul. Wolczanska 213, 93-005, Lodz, Poland
| | - Marcin Bizukojć
- Faculty of Process and Environmental Engineering, Department of Bioprocess Engineering, Lodz University of Technology, ul. Wolczanska 213, 93-005, Lodz, Poland
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3
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Thakur M, Kumar P, Rajput D, Yadav V, Dhaka N, Shukla R, Kumar Dubey K. Genome-guided approaches and evaluation of the strategies to influence bioprocessing assisted morphological engineering of Streptomyces cell factories. BIORESOURCE TECHNOLOGY 2023; 376:128836. [PMID: 36898554 DOI: 10.1016/j.biortech.2023.128836] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/31/2023] [Revised: 03/02/2023] [Accepted: 03/04/2023] [Indexed: 06/18/2023]
Abstract
Streptomyces genera serve as adaptable cell factories for secondary metabolites with various and distinctive chemical structures that are relevant to the pharmaceutical industry. Streptomyces' complex life cycle necessitated a variety of tactics to enhance metabolite production. Identification of metabolic pathways, secondary metabolite clusters, and their controls have all been accomplished using genomic methods. Besides this, bioprocess parameters were also optimized for the regulation of morphology. Kinase families were identified as key checkpoints in the metabolic manipulation (DivIVA, Scy, FilP, matAB, and AfsK) and morphology engineering of Streptomyces. This review illustrates the role of different physiological variables during fermentation in the bioeconomy coupled with genome-based molecular characterization of biomolecules responsible for secondary metabolite production at different developmental stages of the Streptomyces life cycle.
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Affiliation(s)
- Mony Thakur
- Department of Microbiology, Central University of Haryana, Mahendergarh 123031, India
| | - Punit Kumar
- Department of Morphology and Physiology, Karaganda Medical University, Karaganda 100008 Kazakhstan
| | - Deepanshi Rajput
- Bioprocess Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India
| | - Vinod Yadav
- Department of Microbiology, Central University of Haryana, Mahendergarh 123031, India
| | - Namrata Dhaka
- Department of Biotechnology, Central University of Haryana, Mahendergarh 123031, India
| | - Rishikesh Shukla
- Department of Biotechnology, Institute of Applied Sciences and Humanities, GLA University, Mathura- 281406, U.P., India
| | - Kashyap Kumar Dubey
- Bioprocess Engineering Laboratory, School of Biotechnology, Jawaharlal Nehru University, New Delhi 110067, India.
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4
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Fu J, Li C, Ju X, Bai J, Zhou Y, Zhang Y, Wang Y, Sun Z, Hu C, Li L, Ji L. Efficient production of ε-poly-l-lysine from cassava bagasse hydrolysate used as carbon source by Streptomyces albulus US3-18. Bioprocess Biosyst Eng 2022; 45:1407-1419. [DOI: 10.1007/s00449-022-02755-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/06/2022] [Indexed: 11/02/2022]
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5
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Liu Y, Wang K, Pan L, Chen X. Improved Production of ε-Poly-L-Lysine in Streptomyces albulus Using Genome Shuffling and Its High-Yield Mechanism Analysis. Front Microbiol 2022; 13:923526. [PMID: 35711770 PMCID: PMC9195005 DOI: 10.3389/fmicb.2022.923526] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 05/09/2022] [Indexed: 11/29/2022] Open
Abstract
ε-Poly-L-lysine (ε-PL), a natural food preservative, has recently gained interest and mainly produced by Streptomyces albulus. Lacking of efficient breeding methods limit ε-PL production improving, knockout byproducts and increase of main product flux strategies as a logical solution to increase yield. However, removing byproduct formation and improving main product synthesis has seen limited success due to the genetic background of ε-PL producing organism is not clear. To overcome this limitation, random mutagenesis continues to be the best way towards improving strains for ε-PL production. Recent advances in Illumina sequencing opened new avenues to understand improved strains. In this work, we used genome shuffling on strains obtained by ribosome engineering to generate a better ε-PL producing strain. The mutant strain SG-86 produced 144.7% more ε-PL than the parent strain M-Z18. Except that SG-86 displayed obvious differences in morphology and ATP compared to parent strain M-Z18. Using Illumina sequencing, we mapped the genomic changes leading to the improved phenotype. Sequencing two strains showed that the genome of the mutant strain was about 2.1 M less than that of the parent strain, including a large number of metabolic pathways, secondary metabolic gene clusters, and gene deletions. In addition, there are many SNPs (single nucleotide polymorphisms) and InDels (insertions and deletions) in the mutant strain. Based on the results of data analysis, a mechanism of ε-PL overproduction in S. albulus SG-86 was preliminarily proposed. This study is of great significance for improving the fermentation performance and providing theoretical guidance for the metabolic engineering construction of ε-PL producing strains.
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Affiliation(s)
- Yongjuan Liu
- Shandong Provincial Key Laboratory of Synthetic Biology, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, China.,The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,Shandong Energy Institute, Qingdao, China.,Qingdao New Energy Shandong Laboratory, Qingdao, China
| | - Kaifang Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Long Pan
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China.,College of Biological Engineering, Henan University of Technology, Zhengzhou, China
| | - Xusheng Chen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
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Li S, Mao Y, Zhang L, Wang M, Meng J, Liu X, Bai Y, Guo Y. Recent advances in microbial ε-poly-L-lysine fermentation and its diverse applications. BIOTECHNOLOGY FOR BIOFUELS AND BIOPRODUCTS 2022; 15:65. [PMID: 35710433 PMCID: PMC9205021 DOI: 10.1186/s13068-022-02166-2] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 01/04/2022] [Accepted: 06/08/2022] [Indexed: 06/15/2023]
Abstract
The naturally occurring homo-polyamide biopolymer, ε-poly-L-lysine (ε-PL) consists of 25-35 L-lysine residues with amide linkages between α-carboxyl groups and ε-amino groups. ɛ-PL exhibits several useful properties because of its unusual structure, such as biodegradability, water solubility, no human toxicity, and broad-spectrum antibacterial activities; it is widely applied in the fields of food, medicine, clinical chemistry and electronics. However, current industrial production of ε-PL is only performed in a few countries. Based on an analysis of the physiological characteristics of ε-PL fermentation, current advances that enhance ε-PL fermentation, from strain improvement to product isolation are systematically reviewed, focusing on: (1) elucidating the metabolic pathway and regulatory mechanism of ε-PL synthesis; (2) enhancing biosynthetic performance through mutagenesis, fermentation optimization and metabolic engineering; and (3) understanding and improving the biological activity and functional properties of ε-PL. Finally, perspectives on engineering and exploiting ε-PL as a source material for the production of various advanced materials are also discussed, providing scientific guidelines for researchers to further improve the ε-PL fermentation process.
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Affiliation(s)
- Shubo Li
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Yunren Mao
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Lifei Zhang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Miao Wang
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Jinhao Meng
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Xiaoling Liu
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Yunxia Bai
- College of Light Industry and Food Engineering, Guangxi University, Nanning, 530004, China
| | - Yuan Guo
- National Engineering Research Center for Non-Food Biorefinery, Guangxi Academy of Sciences, Nanning, 530004, China.
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7
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Biotechnological production and application of epsilon-poly-L-lysine (ε-PL): biosynthesis and its metabolic regulation. World J Microbiol Biotechnol 2022; 38:123. [PMID: 35637397 DOI: 10.1007/s11274-022-03304-6] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2022] [Accepted: 05/06/2022] [Indexed: 10/18/2022]
Abstract
Epsilon-poly-L-lysine (ε-PL) is an unusual biopolymer composed of L-lysine produced by several microorganisms, especially by the genus Streptomyces. Due to its excellent antimicrobial activity, good water solubility, high safety, and biodegradable nature, ε-PL with a GRAS status has been widely used in food and pharmaceutical industries. In the past years, studies have focused on the biotechnological production of ɛ-PL, the biosynthetic mechanism of microbial ɛ-PL, and its application. To provide new perspectives from recent advances, the review introduced the methods for the isolation of ɛ-PL producing strains and the biosynthetic mechanism of microbial ɛ-PL. We summarized the strategies for the improvement of ɛ-PL producing strains, including physical and chemical mutagenesis, ribosome engineering and gene engineering, and compared the different metabolic regulation strategies for improving ɛ-PL production, including medium optimization, nutrient supply, pH control, and dissolved oxygen control. Then, the downstream purification methods of ɛ-PL and its recent applications in food and medicine industries were introduced. Finally, we also proposed the potential challenges and the perspectives for the production of ε-PL.
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8
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Lajtai-Szabó P, Hülber-Beyer É, Nemestóthy N, Bélafi-Bakó K. The role of physical support in secondary metabolite production by Streptomyces species. Biochem Eng J 2022. [DOI: 10.1016/j.bej.2022.108495] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
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9
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Wang L, Zhang C, Zhang J, Rao Z, Xu X, Mao Z, Chen X. Epsilon-poly-L-lysine: Recent Advances in Biomanufacturing and Applications. Front Bioeng Biotechnol 2021; 9:748976. [PMID: 34650962 PMCID: PMC8506220 DOI: 10.3389/fbioe.2021.748976] [Citation(s) in RCA: 30] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/28/2021] [Accepted: 09/15/2021] [Indexed: 11/30/2022] Open
Abstract
ε-poly-L-lysine (ε-PL) is a naturally occurring poly(amino acid) of varying polymerization degree, which possesses excellent antimicrobial activity and has been widely used in food and pharmaceutical industries. To provide new perspectives from recent advances, this review compares several conventional and advanced strategies for the discovery of wild strains and development of high-producing strains, including isolation and culture-based traditional methods as well as genome mining and directed evolution. We also summarize process engineering approaches for improving production, including optimization of environmental conditions and utilization of industrial waste. Then, efficient downstream purification methods are described, including their drawbacks, followed by the brief introductions of proposed antimicrobial mechanisms of ε-PL and its recent applications. Finally, we discuss persistent challenges and future perspectives for the commercialization of ε-PL.
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Affiliation(s)
- Liang Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Chongyang Zhang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Jianhua Zhang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Zhiming Rao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xueming Xu
- School of Food Science and Technology, Jiangnan University, Wuxi, China
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China
| | - Zhonggui Mao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
| | - Xusheng Chen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, China
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10
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Wang B, Tan F, Yu F, Li H, Zhang M. Efficient biorefinery of whole cassava for citrate production using Aspergillus niger mutated by atmospheric and room temperature plasma and enhanced co-saccharification strategy. JOURNAL OF THE SCIENCE OF FOOD AND AGRICULTURE 2021; 101:4613-4620. [PMID: 33474750 DOI: 10.1002/jsfa.11104] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/13/2020] [Revised: 01/07/2021] [Accepted: 01/20/2021] [Indexed: 06/12/2023]
Abstract
BACKGROUND The non-grain crop cassava has attracted intense attention in the biorefinery process. However, efficient biorefinery of whole cassava is faced with some challenges due to the existence of strain inhibition and refractory cellulose during the citrate production process. RESULTS Here, a novel breeding method - atmospheric and room temperature plasma (ARTP) - was applied for strain improvement of citrate-producing strain Aspergillus niger from whole cassava. The citrate yield of the mutant obtained using ARTP mutagenesis increased by 36.5% in comparison with the original strain. Moreover, citric acid fermentation was further improved on the basis of an enhanced co-saccharification strategy by supplementing glucoamylase and cellulase. The fermentation efficiency increased by 35.8% with a 17.0 g L-1 reduction in residual sugar on a pilot scale. CONCLUSIONS All these results confirmed that a combination of the novel breeding method and enhanced co-saccharification strategy could be used to efficiently refine whole cassava. The results also provide inspiration for the production of value-added products and waste disposal in agro-based industries. © 2021 Society of Chemical Industry.
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Affiliation(s)
- Baoshi Wang
- School of Life Science and Technology, Henan Collaborative Innovation Center in Modern Biological Breeding, Henan Institute of Science and Technology, Xinxiang, China
| | - Fengling Tan
- School of Life Science and Technology, Henan Collaborative Innovation Center in Modern Biological Breeding, Henan Institute of Science and Technology, Xinxiang, China
| | - Feifei Yu
- Shandong Drug and Food Vocational College, Weihai, China
| | - Hua Li
- School of Life Sciences, Institute of Microbial Engineering, Henan University, Kaifeng, China
| | - Mingxia Zhang
- School of Life Science and Technology, Henan Collaborative Innovation Center in Modern Biological Breeding, Henan Institute of Science and Technology, Xinxiang, China
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11
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Kuhl M, Rückert C, Gläser L, Beganovic S, Luzhetskyy A, Kalinowski J, Wittmann C. Microparticles enhance the formation of seven major classes of natural products in native and metabolically engineered actinobacteria through accelerated morphological development. Biotechnol Bioeng 2021; 118:3076-3093. [PMID: 33974270 DOI: 10.1002/bit.27818] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/04/2021] [Revised: 04/17/2021] [Accepted: 04/30/2021] [Indexed: 11/09/2022]
Abstract
Actinobacteria provide a rich spectrum of bioactive natural products and therefore display an invaluable source towards commercially valuable pharmaceuticals and agrochemicals. Here, we studied the use of inorganic talc microparticles (hydrous magnesium silicate, 3MgO·4SiO2 ·H2 O, 10 µm) as a general supplement to enhance natural product formation in this important class of bacteria. Added to cultures of recombinant Streptomyces lividans, talc enhanced production of the macrocyclic peptide antibiotic bottromycin A2 and its methylated derivative Met-bottromycin A2 up to 109 mg L-1 , the highest titer reported so far. Hereby, the microparticles fundamentally affected metabolism. With 10 g L-1 talc, S. lividans grew to 40% smaller pellets and, using RNA sequencing, revealed accelerated morphogenesis and aging, indicated by early upregulation of developmental regulator genes such as ssgA, ssgB, wblA, sigN, and bldN. Furthermore, the microparticles re-balanced the expression of individual bottromycin cluster genes, resulting in a higher macrocyclization efficiency at the level of BotAH and correspondingly lower levels of non-cyclized shunt by-products, driving the production of mature bottromycin. Testing a variety of Streptomyces species, talc addition resulted in up to 13-fold higher titers for the RiPPs bottromycin and cinnamycin, the alkaloid undecylprodigiosin, the polyketide pamamycin, the tetracycline-type oxytetracycline, and the anthramycin-analogs usabamycins. Moreover, talc addition boosted production in other actinobacteria, outside of the genus of Streptomyces: vancomycin (Amycolatopsis japonicum DSM 44213), teicoplanin (Actinoplanes teichomyceticus ATCC 31121), and the angucyclinone-type antibiotic simocyclinone (Kitasatospora sp.). For teicoplanin, the microparticles were even crucial to activate production. Taken together, the use of talc was beneficial in 75% of all tested cases and optimized natural and heterologous hosts forming the substance of interest with clusters under native and synthetic control. Given its simplicity and broad benefits, microparticle-supplementation appears as an enabling technology in natural product research of these most important microbes.
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Affiliation(s)
- Martin Kuhl
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | | | - Lars Gläser
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | - Selma Beganovic
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | - Andriy Luzhetskyy
- Department of Pharmaceutical Biotechnology, Saarland University, Saarbrücken, Germany
| | - Jörn Kalinowski
- Center for Biotechnology, Bielefeld University, Bielefeld, Germany
| | - Christoph Wittmann
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
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12
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Böl M, Schrinner K, Tesche S, Krull R. Challenges of influencing cellular morphology by morphology engineering techniques and mechanical induced stress on filamentous pellet systems-A critical review. Eng Life Sci 2021; 21:51-67. [PMID: 33716605 PMCID: PMC7923580 DOI: 10.1002/elsc.202000060] [Citation(s) in RCA: 14] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 09/25/2020] [Accepted: 09/29/2020] [Indexed: 11/30/2022] Open
Abstract
Filamentous microorganisms are main producers of organic acids, enzymes, and pharmaceutical agents such as antibiotics and other active pharmaceutical ingredients. With their complex cell morphology, ranging from dispersed mycelia to dense pellets, the cultivation is challenging. In recent years, various techniques for tailor-made cell morphologies of filamentous microorganisms have been developed to increase product formation and have been summarised under the term morphology engineering. These techniques, namely microparticle-enhanced cultivation, macroparticle-enhanced cultivation, and alteration of the osmolality of the culture medium by addition of inorganic salts, the salt-enhanced cultivation, are presented and discussed in this review. These techniques have already proven to be useful and now await further proof-of-concept. Furthermore, the mechanical behaviour of individual pellets is of special interest for a general understanding of pellet mechanics and the productivity of biotechnological processes with filamentous microorganisms. Correlating them with substrate uptake and finally with productivity would be a breakthrough not to be underestimated for the comprehensive characterisation of filamentous systems. So far, this research field is under-represented. First results on filamentous pellet mechanics are discussed and important future aspects, which the filamentous expert community should deal with, will be presented and critically discussed.
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Affiliation(s)
- Markus Böl
- Institute of Mechanics and AdaptronicsTechnische Universität BraunschweigBraunschweigGermany
- Center of Pharmaceutical Engineering (PVZ)Technische Universität BraunschweigBraunschweigGermany
| | - Kathrin Schrinner
- Center of Pharmaceutical Engineering (PVZ)Technische Universität BraunschweigBraunschweigGermany
- Institute of Biochemical EngineeringTechnische Universität BraunschweigBraunschweigGermany
| | - Sebastian Tesche
- Center of Pharmaceutical Engineering (PVZ)Technische Universität BraunschweigBraunschweigGermany
- Institute of Biochemical EngineeringTechnische Universität BraunschweigBraunschweigGermany
| | - Rainer Krull
- Center of Pharmaceutical Engineering (PVZ)Technische Universität BraunschweigBraunschweigGermany
- Institute of Biochemical EngineeringTechnische Universität BraunschweigBraunschweigGermany
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13
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Kuhl M, Gläser L, Rebets Y, Rückert C, Sarkar N, Hartsch T, Kalinowski J, Luzhetskyy A, Wittmann C. Microparticles globally reprogram Streptomyces albus toward accelerated morphogenesis, streamlined carbon core metabolism, and enhanced production of the antituberculosis polyketide pamamycin. Biotechnol Bioeng 2020; 117:3858-3875. [PMID: 32808679 DOI: 10.1002/bit.27537] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/19/2020] [Revised: 08/13/2020] [Accepted: 08/14/2020] [Indexed: 12/18/2022]
Abstract
Streptomyces spp. are a rich source for natural products with recognized industrial value, explaining the high interest to improve and streamline the performance of in these microbes. Here, we studied the production of pamamycins, macrodiolide homologs with a high activity against multiresistant pathogenic microbes, using recombinant Streptomyces albus J1074/R2. Talc particles (hydrous magnesium silicate, 3MgO·4SiO2 ·H2 O) of micrometer size, added to submerged cultures of the recombinant strain, tripled pamamycin production up to 50 mg/L. Furthermore, they strongly affected morphology, reduced the size of cell pellets formed by the filamentous microbe during the process up to sixfold, and shifted the pamamycin spectrum to larger derivatives. Integrated analysis of transcriptome and precursor (CoA thioester) supply of particle-enhanced and control cultures provided detailed insights into the underlying molecular changes. The microparticles affected the expression of 3,341 genes (56% of all genes), revealing a global and fundamental impact on metabolism. Morphology-associated genes, encoding major regulators such as SsgA, RelA, EshA, Factor C, as well as chaplins and rodlins, were found massively upregulated, indicating that the particles caused a substantially accelerated morphogenesis. In line, the pamamycin cluster was strongly upregulated (up to 1,024-fold). Furthermore, the microparticles perturbed genes encoding for CoA-ester metabolism, which were mainly activated. The altered expression resulted in changes in the availability of intracellular CoA-esters, the building blocks of pamamycin. Notably, the ratio between methylmalonyl CoA and malonyl-CoA was increased fourfold. Both metabolites compete for incorporation into pamamycin so that the altered availability explained the pronounced preference for larger derivatives in the microparticle-enhanced process. The novel insights into the behavior of S. albus in response to talc appears of general relevance to further explore and upgrade the concept of microparticle enhanced cultivation, widely used for filamentous microbes.
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Affiliation(s)
- Martin Kuhl
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | - Lars Gläser
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
| | - Yuriy Rebets
- Department of Pharmacy, Pharmaceutical Biotechnology, Saarland University, Saarbrücken, Germany
| | | | | | | | - Jörn Kalinowski
- Center for Biotechnology, Bielefeld University, Bielefeld, Germany
| | - Andriy Luzhetskyy
- Department of Pharmacy, Pharmaceutical Biotechnology, Saarland University, Saarbrücken, Germany
| | - Christoph Wittmann
- Institute of Systems Biotechnology, Saarland University, Saarbrücken, Germany
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14
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Wang A, Tian W, Cheng L, Xu Y, Wang X, Qin J, Yu B. Enhanced ε-Poly-L-Lysine Production by the Synergistic Effect of ε-Poly-L-Lysine Synthetase Overexpression and Citrate in Streptomyces albulus. Front Bioeng Biotechnol 2020; 8:288. [PMID: 32391338 PMCID: PMC7188835 DOI: 10.3389/fbioe.2020.00288] [Citation(s) in RCA: 19] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/13/2020] [Accepted: 03/19/2020] [Indexed: 11/13/2022] Open
Abstract
ε-Poly-L-lysine (ε-PL) is a natural amino acid polymer produced by microbial fermentation. It has been mainly used as a preservative in the food and cosmetics industries, as a drug carrier in medicines, and as a gene carrier in gene therapy. ε-PL synthase is the key enzyme responsible for the polymerization of L-lysine to form ε-PL. In this study, the ε-PL synthase gene was overexpressed in Streptomyces albulus CICC 11022 by using the kasOp∗ promoter and the ribosome binding site from the capsid protein of phage ϕC31, which resulted in a genetically engineered strain Q-PL2. The titers of ε-PL produced by Q-PL2 were 88.2% ± 8.3% higher than that produced by the wild strain in shake flask fermentation. With the synergistic effect of 2 g/L sodium citrate, the titers of ε-PL produced by Q-PL2 were 211.2% ± 17.4% higher than that produced by the wild strain. In fed-batch fermentations, 20.1 ± 1.3 g/L of ε-PL was produced by S. albulus Q-PL2 in 72 h with a productivity of 6.7 ± 0.4 g/L/day, which was 3.2 ± 0.3-fold of that produced by the wild strain. These results indicate that ε-PL synthase is one of the rate-limiting enzymes in ε-PL synthesis pathway and lays a foundation for further improving the ε-PL production ability of S. albulus by metabolic engineering.
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Affiliation(s)
- Aixia Wang
- College of Pharmacy, Binzhou Medical University, Yantai, China
| | - Wenzhe Tian
- College of Pharmacy, Binzhou Medical University, Yantai, China
| | - Lei Cheng
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University (BTBU), Beijing, China
| | - Youqiang Xu
- Beijing Engineering and Technology Research Center of Food Additives, Beijing Technology and Business University (BTBU), Beijing, China
| | - Xiuwen Wang
- College of Pharmacy, Binzhou Medical University, Yantai, China
| | - Jiayang Qin
- College of Pharmacy, Binzhou Medical University, Yantai, China
| | - Bo Yu
- CAS Key Laboratory of Microbial Physiological and Metabolic Engineering, Institute of Microbiology, Chinese Academy of Sciences, Beijing, China
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15
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Liu Y, Chen X, Pan L, Mao Z. Differential protein expression of a streptomycin-resistantStreptomyces albulusmutant in high yield production of ε-poly-l-lysine: a proteomics study. RSC Adv 2019; 9:24092-24104. [PMID: 35527895 PMCID: PMC9069503 DOI: 10.1039/c9ra03156a] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2019] [Accepted: 07/12/2019] [Indexed: 12/23/2022] Open
Abstract
ε-Poly-l-lysine (ε-PL), produced by Streptomyces albulus, is an excellent antimicrobial agent which has been extensively used in the field of food and medicine. In our previous study, we have improved ε-PL production by S. albulus M-Z18 through iterative introduction of streptomycin resistance. To decipher the overproduction mechanism of high-yielding mutant S. albulus SS-62, we conducted a comparative proteomics analysis between S. albulus SS-62 and its parent strain S. albulus M-Z18. Approximately 11.5% of the predicted S. albulus proteome was detected and 401 known or putative regulatory proteins showed statistically differential expression levels. Expression levels of proteins involved in ε-PL precursor metabolism and energy metabolism, and proteins in the pathways related to transcriptional regulation and translation were up-regulated. It was indicated that mutant SS-62 could not only strengthen the ε-PL precursor metabolism and energy metabolism but also tune the pathways related to transcriptional regulation and translation, suggesting a better intracellular metabolic environment for the synthesis of ε-PL in mutant SS-62. To confirm these bioinformatics analyses, qRT-PCR was employed to investigate the transcriptional levels of pls, frr and hrdD and their transcription levels were found to have increased more than 4-fold. Further, overexpression of pls and frr resulted in an increase in ε-PL titer and the yield of ε-PL per unit cell. This report not only represents the first comprehensive study on comparative proteomics in S. albulus, but it would also guide strain engineering to further improve ε-PL production. ε-Poly-l-lysine (ε-PL), produced by Streptomyces albulus, is an excellent antimicrobial agent which has been extensively used in the field of food and medicine.![]()
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Affiliation(s)
- Yongjuan Liu
- Key Laboratory of Industrial Biotechnology
- Ministry of Education
- School of Biotechnology
- Jiangnan University
- Wuxi 214122
| | - Xusheng Chen
- Key Laboratory of Industrial Biotechnology
- Ministry of Education
- School of Biotechnology
- Jiangnan University
- Wuxi 214122
| | - Long Pan
- Key Laboratory of Industrial Biotechnology
- Ministry of Education
- School of Biotechnology
- Jiangnan University
- Wuxi 214122
| | - Zhonggui Mao
- Key Laboratory of Industrial Biotechnology
- Ministry of Education
- School of Biotechnology
- Jiangnan University
- Wuxi 214122
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16
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Intergeneric Hybridization between Streptomyces albulus and Bacillus subtilis Facilitates Production of ε-Poly-L-lysine from Corn Starch Residues. BIOTECHNOL BIOPROC E 2018. [DOI: 10.1007/s12257-018-0253-1] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
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17
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Wang L, Li S, Zhao J, Liu Y, Chen X, Tang L, Mao Z. Efficiently activated ε-poly-L-lysine production by multiple antibiotic-resistance mutations and acidic pH shock optimization in Streptomyces albulus. Microbiologyopen 2018; 8:e00728. [PMID: 30298553 PMCID: PMC6528598 DOI: 10.1002/mbo3.728] [Citation(s) in RCA: 21] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2018] [Revised: 08/09/2018] [Accepted: 08/09/2018] [Indexed: 11/17/2022] Open
Abstract
ε‐Poly‐L‐lysine (ε‐PL) is a food additive produced by Streptomyces and is widely used in many countries. Working with Streptomyces albulus FEEL‐1, we established a method to activate ε‐PL synthesis by successive introduction of multiple antibiotic‐resistance mutations. Sextuple mutant R6 was finally developed by screening for resistance to six antibiotics and produced 4.41 g/L of ε‐PL in a shake flask, which is 2.75‐fold higher than the level produced by the parent strain. In a previous study, we constructed a double‐resistance mutant, SG‐31, with high ε‐PL production of 3.83 g/L and 59.50 g/L in a shake flask and 5‐L bioreactor, respectively. However, we found that R6 did not show obvious advantages in fed‐batch fermentation when compared with SG‐31. For further activation of ε‐PL synthesis ability, we optimized the fermentation process by using an effective acidic pH shock strategy, by which R6 synthetized 70.3 g/L of ε‐PL, 2.79‐fold and 1.18‐fold greater than that synthetized by FEEL‐1 and SG‐31, respectively. To the best of our knowledge, this is the highest reported ε‐PL production to date. This ε‐PL overproduction may be due to the result of R99P and Q856H mutations in ribosomal protein S12 and RNA polymerase, respectively, which may be responsible for the increased transcription of the ε‐poly‐lysine synthetase gene (pls) and key enzyme activities in the Lys synthesis metabolic pathway. Consequently, ε‐PL synthetase activity, intracellular ATP, and Lys concentrations were improved and directly contributed to ε‐PL overproduction. This study combined ribosome engineering, high‐throughput screening, and targeted strategy optimization to accelerate ε‐PL production and probe the fermentation characteristics of hyperyield mutants. The information presented here may be useful for other natural products produced by Streptomyces.
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Affiliation(s)
- Liang Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Shu Li
- College of Marine Science, Shandong University (Weihai), Weihai, China
| | - Junjie Zhao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Yongjuan Liu
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Xusheng Chen
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Lei Tang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
| | - Zhonggui Mao
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, Wuxi, Jiangsu, China
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18
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Tao TL, Cui FJ, Chen XX, Sun WJ, Huang DM, Zhang J, Yang Y, Wu D, Liu WM. Improved mycelia and polysaccharide production of Grifola frondosa by controlling morphology with microparticle Talc. Microb Cell Fact 2018; 17:1. [PMID: 29306327 PMCID: PMC5756420 DOI: 10.1186/s12934-017-0850-2] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/29/2017] [Accepted: 12/15/2017] [Indexed: 11/17/2022] Open
Abstract
Background Mushroom showed pellet, clump and/or filamentous mycelial morphologies during submerged fermentation. Addition of microparticles including Talc (magnesium silicate), aluminum oxide and titanium oxide could control mycelial morphologies to improve mycelia growth and secondary metabolites production. Here, effect of microparticle Talc (45 μm) addition on the mycelial morphology, fermentation performance, monosaccharide compositions of polysaccharides and enzymes activities associated with polysaccharide synthesis in G. frondosa was well investigated to find a clue of the relationship between polysaccharide biosynthesis and morphological changes. Results Addition of Talc decreased the diameter of the pellets and increased the percentage of S-fraction mycelia. Talc gave the maximum mycelial biomass of 19.25 g/L and exo-polysaccharide of 3.12 g/L at 6.0 g/L of Talc, and mycelial polysaccharide of 0.24 g/g at 3.0 g/L of Talc. Talc altered the monosaccharide compositions/percentages in G. frondosa mycelial polysaccharide with highest mannose percentage of 62.76 % and lowest glucose percentage of 15.22 % followed with the corresponding changes of polysaccharide-synthesis associated enzymes including lowest UDP-glucose pyrophosphorylase (UGP) activity of 91.18 mU/mg and highest UDP-glucose dehydrogenase (UGDG) and GDP-mannose pyrophosphorylase (GMPPB) activities of 81.45 mU/mg and 93.15 mU/mg. Conclusion Our findings revealed that the presence of Talc significantly changed the polysaccharide production and sugar compositions/percentages in mycelial and exo-polysaccharides by affecting mycelial morphology and polysaccharide-biosynthesis related enzymes activities of G. frondosa.
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Affiliation(s)
- Ting-Lei Tao
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Feng-Jie Cui
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China. .,Jiangxi Provincial Engineering and Technology Center for Food Additives Bio-production, Dexing, 334221, People's Republic of China.
| | - Xiao-Xiao Chen
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Wen-Jing Sun
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China.,Jiangxi Provincial Engineering and Technology Center for Food Additives Bio-production, Dexing, 334221, People's Republic of China
| | - Da-Ming Huang
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
| | - Jinsong Zhang
- National Engineering Research Center of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, 201403, People's Republic of China
| | - Yan Yang
- National Engineering Research Center of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, 201403, People's Republic of China
| | - Di Wu
- National Engineering Research Center of Edible Fungi, Shanghai Academy of Agricultural Sciences, Shanghai, 201403, People's Republic of China
| | - Wei-Min Liu
- School of Food and Biological Engineering, Jiangsu University, Zhenjiang, 212013, People's Republic of China
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19
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Enhanced ε-poly-L-lysine production by inducing double antibiotic-resistant mutations in Streptomyces albulus. Bioprocess Biosyst Eng 2016; 40:271-283. [PMID: 27807681 DOI: 10.1007/s00449-016-1695-5] [Citation(s) in RCA: 20] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/05/2016] [Accepted: 10/13/2016] [Indexed: 10/20/2022]
Abstract
ε-Poly-L-lysine (ε-PL), as a food additive, has been widely used in many countries. However, its production still needs to be improved. We successfully enhanced ε-PL production of Streptomyces albulus FEEL-1 by introducing mutations related to antibiotics, such as streptomycin, gentamicin, and rifampin. Single- and double-resistant mutants (S-88 and SG-31) were finally screened with the improved ε-PL productions of 2.81 and 3.83 g/L, 1.75- to 2.39-fold compared with that of initial strain FEEL-1. Then, the performances of mutants S-88 and SG-31 were compared with the parent strain FEEL-1 in a 5-L bioreactor under the optimal condition for ε-PL production. After 174-h fed-batch fermentation, the ε-PL production and productivity of hyper-strain SG-31 reached the maximum of 59.50 g/L and 8.21 g/L/day, respectively, which was 138 and 105% higher than that of FEEL-1. Analysis of streptomycin-resistant mutants demonstrated that a point mutation occurred in rpsL gene (encoding the ribosomal protein S12). These single and double mutants displayed remarkable increases of the activities and transcriptional levels of key enzymes in ε-PL biosynthesis pathway, which may be responsible for the enhanced mycelia viability, respiratory activity, and ε-PL productions of SG-31. These results showed that the new breeding method, called ribosome engineering, could be a novel and effective breeding strategy for the evolution of ε-PL-producing strains.
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20
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Genome Shuffling and Gentamicin-Resistance to Improve ε-Poly-l-Lysine Productivity of Streptomyces albulus W-156. Appl Biochem Biotechnol 2016; 180:1601-1617. [DOI: 10.1007/s12010-016-2190-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/27/2016] [Accepted: 07/07/2016] [Indexed: 10/21/2022]
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21
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Recent advances in the biotechnological production of microbial poly(ɛ-l-lysine) and understanding of its biosynthetic mechanism. Appl Microbiol Biotechnol 2016; 100:6619-6630. [DOI: 10.1007/s00253-016-7677-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 4.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2016] [Revised: 06/07/2016] [Accepted: 06/11/2016] [Indexed: 01/15/2023]
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22
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Wang B, Chen J, Li H, Sun F, Li Y, Shi G. Efficient production of citric acid in segmented fermentation using Aspergillus niger based on recycling of a pellet-dispersion strategy. RSC Adv 2016. [DOI: 10.1039/c6ra13648f] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022] Open
Abstract
Segmentation recycling fermentation based on a pellet-dispersion strategy to reconstruct the traditional citric acid batch fermentation process is reported.
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Affiliation(s)
- Baoshi Wang
- National Engineering Laboratory for Cereal Fermentation Technology
- Wuxi 214122
- PR China
- School of Biotechology
- Jiangnan University
| | - Jian Chen
- National Engineering Laboratory for Cereal Fermentation Technology
- Wuxi 214122
- PR China
| | - Hua Li
- National Engineering Laboratory for Cereal Fermentation Technology
- Wuxi 214122
- PR China
| | - Fuxin Sun
- Jiangsu Guoxin Union Energy Co., Ltd
- Wuxi 214203
- PR China
| | - Youran Li
- National Engineering Laboratory for Cereal Fermentation Technology
- Wuxi 214122
- PR China
- School of Biotechology
- Jiangnan University
| | - Guiyang Shi
- National Engineering Laboratory for Cereal Fermentation Technology
- Wuxi 214122
- PR China
- School of Biotechology
- Jiangnan University
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