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Zhang X, Liu H, Zhang M, Chen W, Wang C. Enhancing Monascus Pellet Formation for Improved Secondary Metabolite Production. J Fungi (Basel) 2023; 9:1120. [PMID: 37998925 PMCID: PMC10671975 DOI: 10.3390/jof9111120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/13/2023] [Revised: 11/12/2023] [Accepted: 11/16/2023] [Indexed: 11/25/2023] Open
Abstract
Filamentous fungi are well-known for their ability to form mycelial pellets during submerged cultures, a characteristic that has been extensively studied and applied. However, Monascus, a filamentous saprophytic fungus with a rich history of medicinal and culinary applications, has not been widely documented for pellet formation. This study aimed to investigate the factors influencing pellet formation in Monascus and their impact on citrinin production, a key secondary metabolite. Through systematic exploration, we identified pH and inoculum size as critical factors governing pellet formation. Monascus exhibited optimal pellet growth within the acidic pH range from 5 to 6, resulting in smaller, more homogeneous pellets with lower citrinin content. Additionally, we found that inoculum size played a vital role, with lower spore concentrations favoring the formation of small, uniformly distributed pellets. The choice of carbon and nitrogen sources also influenced pellet stability, with glucose, peptone, and fishmeal supporting stable pellet formation. Notably, citrinin content was closely linked to pellet diameter, with larger pellets exhibiting higher citrinin levels. Our findings shed light on optimizing Monascus pellet formation for enhanced citrinin production and provide valuable insights into the cultivation of this fungus for various industrial applications. Further research is warranted to elucidate the molecular mechanisms underlying these observations.
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Affiliation(s)
| | | | | | - Wei Chen
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, School of Food and Health, Beijing Technology and Business University, Beijing 100048, China; (X.Z.); (H.L.); (M.Z.)
| | - Chengtao Wang
- Beijing Advanced Innovation Center for Food Nutrition and Human Health, Beijing Engineering and Technology Research Center of Food Additives, School of Food and Health, Beijing Technology and Business University, Beijing 100048, China; (X.Z.); (H.L.); (M.Z.)
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2
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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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3
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Global Regulator AdpA_1075 Regulates Morphological Differentiation and Ansamitocin Production in Actinosynnema pretiosum subsp. auranticum. Bioengineering (Basel) 2022; 9:bioengineering9110719. [DOI: 10.3390/bioengineering9110719] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/30/2022] [Revised: 11/16/2022] [Accepted: 11/17/2022] [Indexed: 11/23/2022] Open
Abstract
Actinosynnema pretiosum is a well-known producer of maytansinoid antibiotic ansamitocin P-3 (AP-3). Growth of A. pretiosum in submerged culture was characterized by the formation of complex mycelial particles strongly affecting AP-3 production. However, the genetic determinants involved in mycelial morphology are poorly understood in this genus. Herein a continuum of morphological types of a morphologically stable variant was observed during submerged cultures. Expression analysis revealed that the ssgA_6663 and ftsZ_5883 genes are involved in mycelial aggregation and entanglement. Combing morphology observation and morphology engineering, ssgA_6663 was identified to be responsible for the mycelial intertwining during liquid culture. However, down-regulation of ssgA_6663 transcription was caused by inactivation of adpA_1075, gene coding for an AdpA-like protein. Additionally, the overexpression of adpA_1075 led to an 85% increase in AP-3 production. Electrophoretic mobility shift assays (EMSA) revealed that AdpA_1075 may bind the promoter regions of asm28 gene in asm gene cluster as well as the promoter regions of ssgA_6663. These results confirm that adpA_1075 plays a positive role in AP-3 biosynthesis and morphological differentiation.
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4
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de Oliveira F, Ferreira LC, Neto ÁB, Simas Teixeira MF, de Carvalho Santos Ebinuma V. Biosynthesis of natural colorant by Talaromyces amestolkiae: Mycelium accumulation and colorant formation in incubator shaker and in bioreactor. Biochem Eng J 2020. [DOI: 10.1016/j.bej.2020.107694] [Citation(s) in RCA: 9] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
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5
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Enzymatic synthesis of an orlistat intermediate using a mutant short-chain dehydrogenase from Novosphingobium aromaticivorans. Process Biochem 2020. [DOI: 10.1016/j.procbio.2020.02.015] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 01/31/2023]
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6
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Wu Y, Kang Q, Zhang LL, Bai L. Subtilisin-Involved Morphology Engineering for Improved Antibiotic Production in Actinomycetes. Biomolecules 2020; 10:biom10060851. [PMID: 32503302 PMCID: PMC7356834 DOI: 10.3390/biom10060851] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/03/2020] [Revised: 05/27/2020] [Accepted: 05/30/2020] [Indexed: 12/27/2022] Open
Abstract
In the submerged cultivation of filamentous microbes, including actinomycetes, complex morphology is one of the critical process features for the production of secondary metabolites. Ansamitocin P-3 (AP-3), an antitumor agent, is a secondary metabolite produced by Actinosynnema pretiosum ATCC 31280. An excessive mycelial fragmentation of A. pretiosum ATCC 31280 was observed during the early stage of fermentation. Through comparative transcriptomic analysis, a subtilisin-like serine peptidase encoded gene APASM_4178 was identified to be responsible for the mycelial fragmentation. Mutant WYT-5 with the APASM_4178 deletion showed increased biomass and improved AP-3 yield by 43.65%. We also found that the expression of APASM_4178 is specifically regulated by an AdpA-like protein APASM_1021. Moreover, the mycelial fragmentation was alternatively alleviated by the overexpression of subtilisin inhibitor encoded genes, which also led to a 46.50 ± 0.79% yield increase of AP-3. Furthermore, APASM_4178 was overexpressed in salinomycin-producing Streptomyces albus BK 3-25 and validamycin-producing S. hygroscopicus TL01, which resulted in not only dispersed mycelia in both strains, but also a 33.80% yield improvement of salinomycin to 24.07 g/L and a 14.94% yield improvement of validamycin to 21.46 g/L. In conclusion, our work elucidates the involvement of a novel subtilisin-like serine peptidase in morphological differentiation, and modulation of its expression could be an effective strategy for morphology engineering and antibiotic yield improvement in actinomycetes.
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Affiliation(s)
- Yuanting Wu
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200204, China; (Y.W.); (Q.K.)
- Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Qianjin Kang
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200204, China; (Y.W.); (Q.K.)
- Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
| | - Li-Li Zhang
- College of Life Science, Tarim University, Alar 843300, China;
| | - Linquan Bai
- State Key Laboratory of Microbial Metabolism, School of Life Sciences & Biotechnology, Shanghai Jiao Tong University, Shanghai 200204, China; (Y.W.); (Q.K.)
- Joint International Research Laboratory of Metabolic & Developmental Sciences, Shanghai Jiao Tong University, Shanghai 200240, China
- College of Life Science, Tarim University, Alar 843300, China;
- Correspondence:
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7
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Enhanced production of lipstatin from mutant of Streptomyces toxytricini and fed-batch strategies under submerged fermentation. 3 Biotech 2020; 10:151. [PMID: 32181113 DOI: 10.1007/s13205-020-2147-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2019] [Accepted: 02/16/2020] [Indexed: 10/24/2022] Open
Abstract
Streptomyces toxytricini produces bioactive metabolite recognized as lipstatin and its intermediate orlistat. The main focus of this study is to enhance lipstatin production by strain improvement and precursor feeding. In this study, strain improvement to enhance the production of lipstatin was carried out by different doses (50, 100, 150, 200, and 250 Gy) of gamma radiation and precursors (Linoleic acid, Oleic acid, and l-Leucine). Screening showed that the highest yield of lipstatin (4.58 mg/g) was produced by mutant designated as SRN 7. The production of lipstatin (5.011 mg/g) increased significantly when the medium was supplemented with ratio 1:1.5 (linoleic acid + oleic acid). The addition of 1.5% l-Leucine leads to further increment in the production of lipstatin (5.765 mg/g). The addition of 10% soy flour in the culture medium resulted in the maximum production of lipstatin to 5.886 mg/g.
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8
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Gómez-Ríos D, Junne S, Neubauer P, Ochoa S, Ríos-Estepa R, Ramírez-Malule H. Characterization of the Metabolic Response of Streptomyces clavuligerus to Shear Stress in Stirred Tanks and Single-Use 2D Rocking Motion Bioreactors for Clavulanic Acid Production. Antibiotics (Basel) 2019; 8:antibiotics8040168. [PMID: 31569725 PMCID: PMC6963652 DOI: 10.3390/antibiotics8040168] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Revised: 09/22/2019] [Accepted: 09/25/2019] [Indexed: 12/16/2022] Open
Abstract
Streptomyces clavuligerus is a gram-positive filamentous bacterium notable for producing clavulanic acid (CA), an inhibitor of β-lactamase enzymes, which confers resistance to bacteria against several antibiotics. Here we present a comparative analysis of the morphological and metabolic response of S. clavuligerus linked to the CA production under low and high shear stress conditions in a 2D rocking-motion single-use bioreactor (CELL-tainer ®) and stirred tank bioreactor (STR), respectively. The CELL-tainer® guarantees high turbulence and enhanced volumetric mass transfer at low shear stress, which (in contrast to bubble columns) allows the investigation of the impact of shear stress without oxygen limitation. The results indicate that high shear forces do not compromise the viability of S. clavuligerus cells; even higher specific growth rate, biomass, and specific CA production rate were observed in the STR. Under low shear forces in the CELL-tainer® the mycelial diameter increased considerably (average diameter 2.27 in CELL-tainer® vs. 1.44 µm in STR). This suggests that CA production may be affected by a lower surface-to-volume ratio which would lead to lower diffusion and transport of nutrients, oxygen, and product. The present study shows that there is a strong correlation between macromorphology and CA production, which should be an important aspect to consider in industrial production of CA.
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Affiliation(s)
- David Gómez-Ríos
- Grupo de Investigación en Simulación, Diseño, Control y Optimización de Procesos (SIDCOP), Departamento de Ingeniería Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia.
| | - Stefan Junne
- Bioprocess Engineering, Institute of Biotechnology, Technische Universität Berlin, D-13355 Berlin, Germany.
| | - Peter Neubauer
- Bioprocess Engineering, Institute of Biotechnology, Technische Universität Berlin, D-13355 Berlin, Germany.
| | - Silvia Ochoa
- Grupo de Investigación en Simulación, Diseño, Control y Optimización de Procesos (SIDCOP), Departamento de Ingeniería Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia.
| | - Rigoberto Ríos-Estepa
- Grupo de Bioprocesos, Departamento de Ingeniería Química, Universidad de Antioquia UdeA, Calle 70 No. 52-21, Medellín 050010, Colombia.
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9
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Wang L, Yu T, Ma F, Vitus T, Bai S, Yang J. Novel self-immobilized biomass mixture based on mycelium pellets for wastewater treatment: A review. WATER ENVIRONMENT RESEARCH : A RESEARCH PUBLICATION OF THE WATER ENVIRONMENT FEDERATION 2019; 91:93-100. [PMID: 30735302 DOI: 10.1002/wer.1026] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/15/2018] [Revised: 10/19/2018] [Accepted: 11/02/2018] [Indexed: 06/09/2023]
Abstract
Mycelial pellets, as a novel biomass material, can adsorb pollutants as a biosorbent, or combine other substances and organisms to form self-immobilized biomixture (SIB) to remove pollutants from wastewater. The pellets are eco-friendly, have a good self-immobilization capacity, and are easy to filter. In addition, some mycelial fungi can remove the pollutants in water through biodegradation. This study reviewed biomixture based on mycelial pellets and the two ways, through which SIB remove pollutants in water: pure pellets and the pellets with other materials. The characteristics and functions of each part of SIB were discussed. The study also highlighted the shortcomings of the technology and provided recommendations for further development of this technology.
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Affiliation(s)
- Li Wang
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China
| | - Tianmiao Yu
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China
| | - Fang Ma
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China
| | - Tankpa Vitus
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China
| | - Shanshan Bai
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China
| | - Jixian Yang
- State Key Lab of Urban Water Resource and Environment, School of Environment, Harbin Institute of Technology, Harbin, China
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10
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Osadolor OA, Jabbari M, Nair RB, Lennartsson PR, Taherzadeh MJ. Effect of media rheology and bioreactor hydrodynamics on filamentous fungi fermentation of lignocellulosic and starch-based substrates under pseudoplastic flow conditions. BIORESOURCE TECHNOLOGY 2018; 263:250-257. [PMID: 29751232 DOI: 10.1016/j.biortech.2018.04.093] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/24/2018] [Revised: 04/22/2018] [Accepted: 04/23/2018] [Indexed: 06/08/2023]
Abstract
The aim of this work was to study how media rheology and bioreactor hydrodynamics would influence fermentation of lignocellulosic and starch-based substrates under pseudoplastic flow conditions. This was investigated using hydrolyzed wheat straw, wheat-based thin stillage and filamentous fungi as inoculum in bubble column, airlift and horizontal hybrid tubular/bubble column (textile bioreactor) bioreactors. The rheological models showed that the consistency index was dependent on biomass growth (R2 0.99) while the flow behavior index depended on biomass growth and suspended solid (R2 0.99). Oxygen transfer rate above 0.356 mmol-O2/L/h was needed for growing fungi with a cube-root growth rate constant of 0.03 g1/3/L1/3/h. At 1.4 VVM aeration the textile bioreactor performed better than others with minimal foaming, yields of 0.22 ± 0.01 g/g and 0.47 ± 0.01 g/g for ethanol and biomass, substrate consumption rate of 0.38 g/L/h. Operating the bioreactors with air-flowrate to cross-sectional area ratio of 8.75 × 10-3 (m3/s/m2) or more led to sustained foaming.
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Affiliation(s)
- Osagie A Osadolor
- Swedish Centre for Resource Recovery, University of Borås, SE 501 90 Borås, Sweden.
| | - Mostafa Jabbari
- Swedish Centre for Resource Recovery, University of Borås, SE 501 90 Borås, Sweden
| | | | - Patrik R Lennartsson
- Swedish Centre for Resource Recovery, University of Borås, SE 501 90 Borås, Sweden
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11
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Li H, Wang S, Huang Z, Yuan X, Wang Z, He R, Xi Y, Zhang X, Tan M, Huang J, Mo D, Li C. Effect of hydrothermal carbonization on storage process of woody pellets: Pellets' properties and aldehydes/ketones emission. BIORESOURCE TECHNOLOGY 2018; 260:115-123. [PMID: 29625282 DOI: 10.1016/j.biortech.2018.03.095] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/22/2018] [Revised: 03/18/2018] [Accepted: 03/19/2018] [Indexed: 06/08/2023]
Abstract
Effect of hydrothermal carbonization (HTC) on the hydrochar pelletization and the aldehydes/ketones emission from pellets during storage was investigated. Pellets made from the hydrochar were stored in sealed apparatuses for sampling. The energy consumption during pelletization and the pellets' properties before/after storage, including dimension, density, moisture content, hardness, aldehyde/ketones emission amount/rate and unsaturated fatty acid amount, were analyzed. Compared with untreated-sawdust-pellets, the hydrochar-pellets required more energy consumption for pelletization, and achieved the improved qualities, resulting in the higher stability degree during storage. The species and amount of unsaturated fatty acids in the hydrochar-pellets were higher than those in the untreated-sawdust-pellets. The unsaturated fatty acids content in the hydrochar-pellets was decreased with increasing HTC temperature. Higher aldehydes/ketones emission amount and rates with a longer emission period were found for the hydrochar-pellets, associated with variations of structure and unsaturated fatty acid composition in pellets.
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Affiliation(s)
- Hui Li
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China.
| | - Siyuan Wang
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China
| | - Zhongliang Huang
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China
| | - Xingzhong Yuan
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China
| | - Ziliang Wang
- Department of Chemical and Biological Engineering, University of British Columbia, Vancouver V6T 1Z3, Canada
| | - Rao He
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China
| | - Yanni Xi
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China; College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China
| | - Xuan Zhang
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China
| | - Mengjiao Tan
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China; College of Resource and Environment, Hunan Agricultural University, Changsha 410128, PR China
| | - Jing Huang
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China
| | - Dan Mo
- College of Environmental Science and Engineering, Hunan University, Changsha 410082, PR China
| | - Changzhu Li
- Institute of Biological and Environmental Engineering, Hunan Academy of Forestry, Changsha 410004, PR China
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12
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Streptomyces clavuligerus shows a strong association between TCA cycle intermediate accumulation and clavulanic acid biosynthesis. Appl Microbiol Biotechnol 2018. [PMID: 29523936 DOI: 10.1007/s00253-018-8841-8] [Citation(s) in RCA: 17] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Clavulanic acid (CA) is produced by Streptomyces clavuligerus (S. clavuligerus) as a secondary metabolite. Knowledge about the carbon flux distribution along the various routes that supply CA precursors would certainly provide insights about metabolic performance. In order to evaluate metabolic patterns and the possible accumulation of tricarboxylic acid (TCA) cycle intermediates during CA biosynthesis, batch and subsequent continuous cultures with steadily declining feed rates were performed with glycerol as the main substrate. The data were used to in silico explore the metabolic capabilities and the accumulation of metabolic intermediates in S. clavuligerus. While clavulanic acid accumulated at glycerol excess, it steadily decreased at declining dilution rates; CA synthesis stopped when glycerol became the limiting substrate. A strong association of succinate, oxaloacetate, malate, and acetate accumulation with CA production in S. clavuligerus was observed, and flux balance analysis (FBA) was used to describe the carbon flux distribution in the network. This combined experimental and numerical approach also identified bottlenecks during the synthesis of CA in a batch and subsequent continuous cultivation and demonstrated the importance of this type of methodologies for a more advanced understanding of metabolism; this potentially derives valuable insights for future successful metabolic engineering studies in S. clavuligerus.
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13
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Kumar P, Dubey KK. Implication of mutagenesis and precursor supplementation towards the enhancement of lipstatin (an antiobesity agent) biosynthesis through submerged fermentation using Streptomyces toxytricini. 3 Biotech 2018; 8:29. [PMID: 29291142 PMCID: PMC5742565 DOI: 10.1007/s13205-017-1049-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/21/2017] [Accepted: 12/17/2017] [Indexed: 11/28/2022] Open
Abstract
In the present study, lipstatin production was studied from different mutants of Streptomyces toxytricini which were developed using ultraviolet radiation (exposure time 30 s, 1, 2, 5 and 10 min), ethyl methane sulfonte, methyl methane sulfonate (MMS) and N-methyl-N'-intro-N-nitrosoguanidine (NTG) treatments (50, 100, 200, 500, 1000 µM, respectively). Highest yielding mutants were provided precursor supplementation of citric acid, thiamine and biotin (each 1 g/L) at idiophase for further enhancement in the production of lipstatin. Screened mutants produced biomass in the range of 5.8-7.16 g/L which were lesser than control. Screened mutants also exhibited pellet morphology in submerged culture. Out of these mutants, NTG8 mutant produced highest amount of lipstatin (1383.25 mg/L) with 9.606 mg/L/h productivity. Precursor supplementation to this mutant further increased the production to 2387.81 mg/L. Mutant was validated in 5 L bioreactor and lipstatin production was enhanced to 2519.34 mg/L.
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Affiliation(s)
- Punit Kumar
- Microbial Process Development Laboratory, University Institute of Engineering and Technology, Maharshi Dayanand University, Rohtak, Haryana 124001 India
| | - Kashyap Kumar Dubey
- Microbial Process Development Laboratory, University Institute of Engineering and Technology, Maharshi Dayanand University, Rohtak, Haryana 124001 India
- Department of Biotechnology, Central University of Haryana, Mahendergarh, Haryana 123031 India
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14
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Híreš M, Rapavá N, Šimkovič M, Varečka Ľ, Berkeš D, Kryštofová S. Development and Optimization of a High-Throughput Screening Assay for Rapid Evaluation of Lipstatin Production by Streptomyces Strains. Curr Microbiol 2017; 75:580-587. [PMID: 29256008 DOI: 10.1007/s00284-017-1420-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/26/2017] [Accepted: 12/11/2017] [Indexed: 11/24/2022]
Abstract
Pancreatic lipase inhibitors, such as tetrahydrolipstatin (orlistat), are used in anti-obesity treatments. Orlistat is the only anti-obesity drug approved by the European Medicines Agency (EMA). The drug is synthesized by saturation of lipstatin, a β-lactone compound, isolated from Streptomyces toxytricini and S. virginiae. To identify producers of novel pancreatic lipase inhibitors or microbial strains with improved lipstatin production and higher chemical purity remains still a priority. In this study, a high-throughput screening method to identify Streptomyces strains producing potent pancreatic lipase inhibitors was established. The assay was optimized and validated using S. toxytricini NRRL 15443 and its mutants. Strains grew in 24-well titer plates. Lipstatin levels were assessed directly in culture medium at the end of cultivation by monitoring lipolytic activity in the presence of a chromogenic substrate, 1,2-Di-O-lauryl-rac-glycero-3-glutaric acid 6-methylresorufin ester (DGGR). The lipase activity decreased in response to lipstatin production, and this was demonstrated by accumulation of red-purple methylresorufin, a product of DGGR digestion. The sensitivity of the assay was achieved by adding a lipase of high lipolytic activity and sensitivity to lipstatin to the reaction mixture. In the assay, the fungal lipase from Mucor javanicus was used as an alternative to the human pancreatic lipase. Many fungal lipases preserve high lipolytic activity in extreme conditions and are not colipase dependent. The assay proved to be reliable in differentiation of strains with high and low lipstatin productivity.
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Affiliation(s)
- Michal Híreš
- Institute of Biochemistry and Microbiology, Slovak University of Technology, Radlinského 9, 81 237, Bratislava, Slovakia.
| | - Nora Rapavá
- Institute of Biochemistry and Microbiology, Slovak University of Technology, Radlinského 9, 81 237, Bratislava, Slovakia
| | - Martin Šimkovič
- Institute of Biochemistry and Microbiology, Slovak University of Technology, Radlinského 9, 81 237, Bratislava, Slovakia
| | - Ľudovít Varečka
- Institute of Biochemistry and Microbiology, Slovak University of Technology, Radlinského 9, 81 237, Bratislava, Slovakia
| | - Dušan Berkeš
- Department of Organic Chemistry, Slovak University of Technology, Radlinského 9, 81 237, Bratislava, Slovakia
| | - Svetlana Kryštofová
- Institute of Biochemistry and Microbiology, Slovak University of Technology, Radlinského 9, 81 237, Bratislava, Slovakia
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