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Lima FA, Santos OS, Pomella AWV, Ribeiro EJ, Resende MM. Culture Medium Evaluation Using Low‐Cost Substrate for Biosurfactants Lipopeptides Production by
Bacillus amyloliquefaciens
in Pilot Bioreactor. J SURFACTANTS DETERG 2019. [DOI: 10.1002/jsde.12350] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Affiliation(s)
- Frederico A. Lima
- Chemical Engineering FacultyFederal University of Uberlândia, P.O. Box 593, Av. João Naves de Ávila 2121, Campus Santa Mônica, Bloco 1K Uberlândia MG 38408‐144 Brazil
| | - Olga Silva Santos
- Chemical Engineering FacultyFederal University of Uberlândia, P.O. Box 593, Av. João Naves de Ávila 2121, Campus Santa Mônica, Bloco 1K Uberlândia MG 38408‐144 Brazil
| | - Alan William Vilela Pomella
- Laboratório de BioControle Farroupilha S.A., Lallemand, Av. Júlia Fernandes Caixeta n°55, Bairro Cidade Nova Patos de Minas MG 38706‐420 Brazil
| | - Eloízio J. Ribeiro
- Chemical Engineering FacultyFederal University of Uberlândia, P.O. Box 593, Av. João Naves de Ávila 2121, Campus Santa Mônica, Bloco 1K Uberlândia MG 38408‐144 Brazil
| | - Miriam Maria Resende
- Chemical Engineering FacultyFederal University of Uberlândia, P.O. Box 593, Av. João Naves de Ávila 2121, Campus Santa Mônica, Bloco 1K Uberlândia MG 38408‐144 Brazil
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Ogawara H. Comparison of Antibiotic Resistance Mechanisms in Antibiotic-Producing and Pathogenic Bacteria. Molecules 2019; 24:E3430. [PMID: 31546630 PMCID: PMC6804068 DOI: 10.3390/molecules24193430] [Citation(s) in RCA: 42] [Impact Index Per Article: 8.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2019] [Revised: 09/18/2019] [Accepted: 09/20/2019] [Indexed: 12/13/2022] Open
Abstract
Antibiotic resistance poses a tremendous threat to human health. To overcome this problem, it is essential to know the mechanism of antibiotic resistance in antibiotic-producing and pathogenic bacteria. This paper deals with this problem from four points of view. First, the antibiotic resistance genes in producers are discussed related to their biosynthesis. Most resistance genes are present within the biosynthetic gene clusters, but some genes such as paromomycin acetyltransferases are located far outside the gene cluster. Second, when the antibiotic resistance genes in pathogens are compared with those in the producers, resistance mechanisms have dependency on antibiotic classes, and, in addition, new types of resistance mechanisms such as Eis aminoglycoside acetyltransferase and self-sacrifice proteins in enediyne antibiotics emerge in pathogens. Third, the relationships of the resistance genes between producers and pathogens are reevaluated at their amino acid sequence as well as nucleotide sequence levels. Pathogenic bacteria possess other resistance mechanisms than those in antibiotic producers. In addition, resistance mechanisms are little different between early stage of antibiotic use and the present time, e.g., β-lactam resistance in Staphylococcus aureus. Lastly, guanine + cytosine (GC) barrier in gene transfer to pathogenic bacteria is considered. Now, the resistance genes constitute resistome composed of complicated mixture from divergent environments.
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Affiliation(s)
- Hiroshi Ogawara
- HO Bio Institute, 33-9, Yushima-2, Bunkyo-ku, Tokyo 113-0034, Japan.
- Department of Biochemistry, Meiji Pharmaceutical University, 522-1, Noshio-2, Kiyose, Tokyo 204-8588, Japan.
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53
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Zhou D, Hu F, Lin J, Wang W, Li S. Genome and transcriptome analysis of Bacillus velezensis BS-37, an efficient surfactin producer from glycerol, in response to d-/l-leucine. Microbiologyopen 2019; 8:e00794. [PMID: 30793535 PMCID: PMC6692528 DOI: 10.1002/mbo3.794] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2018] [Revised: 12/06/2018] [Accepted: 12/08/2018] [Indexed: 11/12/2022] Open
Abstract
Surfactin is one of the most widely studied biosurfactants due to its many potential applications in different fields. In the present study, Bacillus velezensis BS-37, initially identified as a strain of Bacillus subtilis, was used to efficiently produce surfactin with the addition of glycerol, an inexpensive by-product of biodiesel production. After 36 hr of growth in glycerol medium, the total surfactin concentration reached more than 1,000 mg/L, which was two times higher than that in sucrose medium. Moreover, the addition of l- and d-Leu to the culture medium had opposite effects on surfactin production by BS-37. While surfactin production increased significantly to nearly 2,000 mg/L with the addition of 10 mM l-Leu, it was dramatically reduced to about 250 mg/L with the addition of 10 mM d-Leu. To systemically elucidate the mechanisms influencing the efficiency of this biosynthesis process, we sequenced the genome of BS-37 and analyzed changes of the transcriptome in glycerol medium in response to d-/l-leucine. The RPKM analysis of the transcriptome of BS-37 showed that the transcription levels of genes encoding modular surfactin synthase, the glycerol utilization pathway, and branched-chain amino acid (BCAA) synthesis pathways were all at a relatively high level, which may offered an explanation why this strain can efficiently use glycerol to produce surfactin with a high yield. Neither l-Leu nor d-Leu had a significant effect on the expression of genes in these pathways, indicating that l-Leu plays an important role as a precursor or substrate involved in surfactin production, while d-Leu appears to act as a competitive inhibitor. The results of the present study provide new insights into the synthesis of surfactin and ways of its regulation, and enrich the genomic and transcriptomic resources available for the construction of high-producing strains.
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Affiliation(s)
- Dayuan Zhou
- College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjingChina
| | - Fangxiang Hu
- College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjingChina
| | - Junzhang Lin
- Oil Production Research InstituteShengli Oil Field Ltd. Co. SinoPECDongyingChina
| | - Weidong Wang
- Oil Production Research InstituteShengli Oil Field Ltd. Co. SinoPECDongyingChina
| | - Shuang Li
- College of Biotechnology and Pharmaceutical EngineeringNanjing Tech UniversityNanjingChina
- Jiangsu National Synergetic Innovation Center for Advanced Materials (SICAM)Nanjing Tech UniversityNanjingChina
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Lu JY, Zhou K, Huang WT, Zhou P, Yang S, Zhao X, Xie J, Xia L, Ding X. A comprehensive genomic and growth proteomic analysis of antitumor lipopeptide bacillomycin Lb biosynthesis in Bacillus amyloliquefaciens X030. Appl Microbiol Biotechnol 2019; 103:7647-7662. [PMID: 31352508 DOI: 10.1007/s00253-019-10019-6] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/21/2019] [Revised: 07/05/2019] [Accepted: 07/09/2019] [Indexed: 12/23/2022]
Abstract
Lipopeptides (such as iturin, fengycin, and surfactin) from Bacillus possess antibacterial, antifungal, and antiviral activities and have important application in agriculture and pharmaceuticals. Although unremitting efforts have been devoted to improve lipopeptide production by designing gene regulatory circuits or optimizing fermentation process, little attention has been paid to utilizing multi-omics for systematically mining core genes and proteins during the bacterial growth cycle. Here, lipopeptide bacillomycin Lb from new Bacillus amyloliquefaciens X030 was isolated and first found to have anticancer activity in various cancer cells (such as SMMC-7721 and MDA-MB-231). A comprehensive genomic and growth proteomic analysis of X030 revealed bacillomycin Lb biosynthetic gene cluster, key enzymes and potential regulatory proteins (PerR, PhoP, CcpA, and CsfB), and novel links between primary metabolism and bacillomycin Lb production in X030. The antitumor activity of the fermentation supernatant supplemented with amino acids (such as glutamic acid) and sucrose was significantly increased, verifying the role of key metabolic switches in the metabolic regulatory network. Quantitative real-time PCR analysis confirmed that 7 differential expressed genes exhibited a positive correlation between changes at transcriptional and translational levels. The study not only will stimulate the deeper and wider antitumor study of lipopeptides but also provide a comprehensive database, which promotes an in-depth analysis of pathways and networks for complex events in lipopeptide biosynthesis and regulation and gives great help in improving the yield of bacillomycin Lb (media optimization, genetic modification, or pathway engineering).
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Affiliation(s)
- Jiao Yang Lu
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Kexuan Zhou
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Wei Tao Huang
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Pengji Zhou
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Shuqing Yang
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Xiaoli Zhao
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Junyan Xie
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Liqiu Xia
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China
| | - Xuezhi Ding
- State Key Laboratory of Developmental Biology of Freshwater Fish, Hunan Provincial Key Laboratory of Microbial Molecular Biology, College of Life Science, Hunan Normal University, Changsha, 410081, People's Republic of China.
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Kaspar F, Neubauer P, Gimpel M. Bioactive Secondary Metabolites from Bacillus subtilis: A Comprehensive Review. JOURNAL OF NATURAL PRODUCTS 2019; 82:2038-2053. [PMID: 31287310 DOI: 10.1021/acs.jnatprod.9b00110] [Citation(s) in RCA: 116] [Impact Index Per Article: 23.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/09/2023]
Abstract
Bacillus subtilis is widely underappreciated for its inherent biosynthetic potential. This report comprehensively summarizes the known bioactive secondary metabolites from B. subtilis and highlights potential applications as plant pathogen control agents, drugs, and biosurfactants. B. subtilis is well known for the production of cyclic lipopeptides exhibiting strong surfactant and antimicrobial activities, such as surfactins, iturins, and fengycins. Several polyketide-derived macrolides as well as nonribosomal peptides, dihydroisocoumarins, and linear lipopeptides with antimicrobial properties have been reported, demonstrating the biosynthetic arsenal of this bacterium. Promising efforts toward the application of B. subtilis strains and their natural products in areas of agriculture and medicine are underway. However, industrial-scale availability of these compounds is currently limited by low fermentation yields and challenging accessibility via synthesis, necessitating the development of genetically engineered strains and optimized cultivation processes. We hope that this review will attract renewed interest in this often-overlooked bacterium and its impressive biosynthetic skill set.
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Affiliation(s)
- Felix Kaspar
- Institute of Biotechnology , Technical University of Berlin , Ackerstraße 76 , 13355 Berlin , Germany
| | - Peter Neubauer
- Institute of Biotechnology , Technical University of Berlin , Ackerstraße 76 , 13355 Berlin , Germany
| | - Matthias Gimpel
- Institute of Biotechnology , Technical University of Berlin , Ackerstraße 76 , 13355 Berlin , Germany
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Marine Biosurfactants: Biosynthesis, Structural Diversity and Biotechnological Applications. Mar Drugs 2019; 17:md17070408. [PMID: 31323998 PMCID: PMC6669457 DOI: 10.3390/md17070408] [Citation(s) in RCA: 54] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/17/2019] [Revised: 07/04/2019] [Accepted: 07/07/2019] [Indexed: 11/16/2022] Open
Abstract
Biosurfactants are amphiphilic secondary metabolites produced by microorganisms. Marine bacteria have recently emerged as a rich source for these natural products which exhibit surface-active properties, making them useful for diverse applications such as detergents, wetting and foaming agents, solubilisers, emulsifiers and dispersants. Although precise structural data are often lacking, the already available information deduced from biochemical analyses and genome sequences of marine microbes indicates a high structural diversity including a broad spectrum of fatty acid derivatives, lipoamino acids, lipopeptides and glycolipids. This review aims to summarise biosyntheses and structures with an emphasis on low molecular weight biosurfactants produced by marine microorganisms and describes various biotechnological applications with special emphasis on their role in the bioremediation of oil-contaminated environments. Furthermore, novel exploitation strategies are suggested in an attempt to extend the existing biosurfactant portfolio.
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57
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Wang C, Cao Y, Wang Y, Sun L, Song H. Enhancing surfactin production by using systematic CRISPRi repression to screen amino acid biosynthesis genes in Bacillus subtilis. Microb Cell Fact 2019; 18:90. [PMID: 31122258 PMCID: PMC6533722 DOI: 10.1186/s12934-019-1139-4] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/07/2019] [Accepted: 05/17/2019] [Indexed: 11/12/2022] Open
Abstract
Background Surfactin is a cyclic lipopeptide that is of great industrial use owing to its extraordinary surfactant power and antimicrobial, antiviral, and antitumor activities. Surfactin is synthesized by a condensation reaction in microbes, which uses fatty acids and four kinds of amino acids (l-glutamate, l-aspartate, l-leucine and l-valine) as precursors. Surfactin biosynthesis could be improved by increasing the supply of fatty acids; however, the effect of the regulation of amino acid metabolism on surfactin production was not yet clear. Results In this study, we aimed to improve surfactin production in B. subtilis by repressing the genes on the branch metabolic pathways of amino acid biosynthesis using CRISPRi technology. First, 20 genes were inhibited individually, resulting in 2.5- to 627-fold decreases in transcriptional level as determined by RT-qPCR. Among the 20 recombinant strains, 16 strains obtained higher surfactin titres than that produced by the parent BS168NU-Sd strain (the surfactin production of BS168NU-Sd with only dCas9 but no sgRNA expression was 0.17 g/L). In particular, the strains in which the yrpC, racE or murC genes were inhibited individually produced 0.54, 0.41, or 0.42 g/L surfactin, respectively. All three genes are related to the metabolism of l-glutamate, whose acylation is the first step in the surfactin condensation reaction. Furthermore, these three genes were repressed in combination, and the strain with co-inhibition of yrpC and racE produced 0.75 g/L surfactin, which was 4.69-fold higher than that of the parent strain. In addition, the inhibition of bkdAA and bkdAB, which are related to the metabolism of l-leucine and l-valine, not only improved surfactin production but also increased the proportion of the C14 isoform. Conclusions This study, to the best of our knowledge for the first time, systematically probed the regulatory effect of increasing the supply of amino acids on surfactin production. It provided an effective strategy and a new perspective for systematic studies on surfactin and other amino acid-derived chemicals. Electronic supplementary material The online version of this article (10.1186/s12934-019-1139-4) contains supplementary material, which is available to authorized users.
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Affiliation(s)
- Congya Wang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, People's Republic of China
| | - Yingxiu Cao
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, People's Republic of China
| | - Yongping Wang
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, People's Republic of China
| | - Liming Sun
- Petrochemical Research Institute, PetroChina Company Limited, Beijing, 102206, China
| | - Hao Song
- Frontier Science Center for Synthetic Biology and Key Laboratory of Systems Bioengineering (MOE), School of Chemical Engineering and Technology, Tianjin University, Tianjin, 300350, People's Republic of China.
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Deng Q, Wang R, Sun D, Sun L, Wang Y, Pu Y, Fang Z, Xu D, Liu Y, Ye R, Yin S, Xie S, Gooneratne R. Complete Genome of Bacillus velezensis CMT-6 and Comparative Genome Analysis Reveals Lipopeptide Diversity. Biochem Genet 2019; 58:1-15. [PMID: 31098827 DOI: 10.1007/s10528-019-09927-z] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2018] [Accepted: 05/07/2019] [Indexed: 12/30/2022]
Abstract
The complete genome sequence of Bacillus velezensis type strain CMT-6 is presented for the first time. A comparative analysis between the genome sequences of CMT-6 with the genome of Bacillus amyloliquefaciens DSM7T, B. velezensis FZB42, and Bacillus subtilis 168 revealed major differences in the lipopeptide synthesis genes. Of the above, only the CMT-6 strain possessed an integrated synthetase gene for synthesizing surfactin, iturin, and fengycin. However, CMT-6 shared 14, 12, and 10 other lipopeptide-producing genes with FZB42, DSM7T, and 168 respectively. The largest numbers of non-synonymous mutations were detected in 205 gene sequences that produced these three lipopeptides in CMT-6 and 168. Comparing CMT-6 with DSM7T, 58 non-synonymous mutations were detected in gene sequences that contributed to produce lipopeptides. In addition, InDels were identified in yczE and glnR genes. CMT-6 and FZB42 had the lowest number of non-synonymous mutations with 8 lipopeptide-related gene sequences. And InDels were identified in only yczE. The numbers of core genes, InDels, and non-synonymous mutations in genes were the main reasons for the differences in yield and variety of lipopeptides. These results will enrich the genomic resources available for B. velezensis and provide fundamental information to construct strains that can produce specific lipopeptides.
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Affiliation(s)
- Qi Deng
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China
| | - Rundong Wang
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China
| | - Dongfang Sun
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China
| | - Lijun Sun
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China.
| | - Yaling Wang
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China.
| | - Yuehua Pu
- Guangdong Institute of Special Equipment Inspection and Research Zhanjiang Branch, Zhanjiang, 524022, China
| | - Zhijia Fang
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China
| | - Defeng Xu
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China
| | - Ying Liu
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China
| | - Riying Ye
- Guangdong Provincial Key Laboratory of Aquatic Product Processing and Safety, Key Laboratory of Advanced Processing of Aquatic Products of Guangdong Higher Education Institution, College of Food Science and Technology, Guangdong Ocean University, No. 1 Haida Road, Zhanjiang, 524088, Guangdong Province, China
| | - Sanjun Yin
- Health Time Gene Institute, Shenzhen, 518000, China
| | - Sisi Xie
- Health Time Gene Institute, Shenzhen, 518000, China
| | - Ravi Gooneratne
- Department of Wine, Food and Molecular Biosciences, Lincoln University, Lincoln, 7647, New Zealand
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Hu F, Liu Y, Li S. Rational strain improvement for surfactin production: enhancing the yield and generating novel structures. Microb Cell Fact 2019; 18:42. [PMID: 30819187 PMCID: PMC6394072 DOI: 10.1186/s12934-019-1089-x] [Citation(s) in RCA: 70] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/14/2018] [Accepted: 02/18/2019] [Indexed: 01/10/2023] Open
Abstract
Surfactin, one of the most powerful microbial surfactants, is a lipopeptide-type biosurfactant which combines interesting physicochemical properties and biological activities. However, the high cost caused by its low productivity largely limits the commercial application of surfactin. Hence, many engineered bacterium have also been used to enhance surfactin biosynthesis. This review briefly summarizes the mechanism of surfactin biosynthesis, highlighting the synthesis pathway of N-terminally attached fatty acids, and outlines the main genetic engineering strategies for improving the yield and generating novel structures of surfactin, including promoter engineering, enhancing efflux systems, modifying the transcriptional regulatory genes of surfactin synthase (srfA), genomics and transcriptomics analysis, non ribosomal peptide synthetase (NRPS) domain and combinatorial biosynthesis. Finally, we discuss the future prospects of the research on surfactin.
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Affiliation(s)
- Fangxiang Hu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing, Jiangsu, China
| | - Yuyue Liu
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing, Jiangsu, China
| | - Shuang Li
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, No. 30 Puzhu South Road, Nanjing, Jiangsu, China.
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Wang M, Yu H, Shen Z. Antisense RNA-Based Strategy for Enhancing Surfactin Production in Bacillus subtilis TS1726 via Overexpression of the Unconventional Biotin Carboxylase II To Enhance ACCase Activity. ACS Synth Biol 2019; 8:251-256. [PMID: 30702274 DOI: 10.1021/acssynbio.8b00459] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The antisense RNA (asRNA) strategy is commonly used to block protein expression and downregulate the contents of metabolites in several microorganisms. Here, we show that the asRNA strategy can also be used to block gfp expression in Bacillus subtilis TS1726, which could further be utilized in the identification of new genes and functions. Via application of this strategy, biotin carboxylase II encoded by yngH (GeneID 939474) was identified to play a more significant role in maintaining acetyl-CoA carboxylase (ACCase) activity and enhancing surfactin synthesis compared to those of other ACCase subunits. The yngH gene was then overexpressed in the engineered strain B. subtilis TS1726(yngH). The surfactin titer of TS1726(yngH) increased to 13.37 g/L in a flask culture, representing a 43% increase compared to that of parental strain TS1726. This strategy opens the door to achieving large-scale production and broad application of surfactin.
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Affiliation(s)
- Miaomiao Wang
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, P. R. China
- Key Laboratory of Industrial Biocatalysis (Tsinghua University), Ministry of Education, Beijing 100084, P. R. China
| | - Huimin Yu
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, P. R. China
- Key Laboratory of Industrial Biocatalysis (Tsinghua University), Ministry of Education, Beijing 100084, P. R. China
- Center for Synthetic and Systems Biology, Tsinghua University, Beijing 100084, P. R. China
| | - Zhongyao Shen
- Department of Chemical Engineering, Tsinghua University, Beijing 100084, P. R. China
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Santos VSV, Silveira E, Pereira BB. Toxicity and applications of surfactin for health and environmental biotechnology. JOURNAL OF TOXICOLOGY AND ENVIRONMENTAL HEALTH. PART B, CRITICAL REVIEWS 2019; 21:382-399. [PMID: 30614421 DOI: 10.1080/10937404.2018.1564712] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/27/2023]
Abstract
Characterized as one of the most potent biosurfactants, surfactin is a cyclic lipopeptide synthesized by several strains of Bacillus genus. The aim of this review was to present the physicochemical and structural properties of surfactin and to demonstrate advances and applications of this biosurfactant for health and environmental biotechnology. Further, this review also focused on toxicological effects of surfactin on in vivo and in in vitro systems. The hydrophobic nature of surfactin enables interaction with membrane-bound phospholipids and indicates the ability of the molecule to act as a new weapon with respect to therapeutic and environmental properties. Seeking to avoid environmental contamination produced by widespread use of synthetic surfactants, surfactin emerges as a biological control agent against pathogen species owing to its antibacterial and antiviral properties. In addition, the mosquitocidal activity of surfactin was suggested as new strategy to control disease vectors. The current findings warrant future research to assess the toxicity of surfactin to enable an optimizing anticancer therapy and to seek refined methodologies, including nanotechnology techniques, to allow for an improved delivery of the biogenic molecule on target cells.
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Affiliation(s)
- Vanessa Santana Vieira Santos
- a Department of Environmental Health, Laboratory of Environmental Health , Federal University of Uberlândia, Santa Mônica Campus , Uberlândia , Brazil
- b Institute of Biotechnology, Department of Biotechnology , Federal University of Uberlândia, Umuarama Campus , Uberlândia , Brazil
| | - Edgar Silveira
- b Institute of Biotechnology, Department of Biotechnology , Federal University of Uberlândia, Umuarama Campus , Uberlândia , Brazil
| | - Boscolli Barbosa Pereira
- a Department of Environmental Health, Laboratory of Environmental Health , Federal University of Uberlândia, Santa Mônica Campus , Uberlândia , Brazil
- b Institute of Biotechnology, Department of Biotechnology , Federal University of Uberlândia, Umuarama Campus , Uberlândia , Brazil
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Zhu Z, Zhang B, Chen B, Ling J, Cai Q, Husain T. Fly ash based robust biocatalyst generation: a sustainable strategy towards enhanced green biosurfactant production and waste utilization. RSC Adv 2019; 9:20216-20225. [PMID: 35514694 PMCID: PMC9065571 DOI: 10.1039/c9ra02784j] [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: 04/12/2019] [Accepted: 06/04/2019] [Indexed: 12/13/2022] Open
Abstract
Biosurfactants have been well recognized as an environmentally friendly alternative to chemical surfactants. However, their production remains challenging due to low productivity, short-term microbe stability and the potentially toxic by-products generated in the growth media. To overcome these challenges, the emerging biofilm-based biosynthesis was investigated in this study. A fresh insight into the biosynthesis process was provided through using waste fly ash as a carrier material. The biofilm produced by biosurfactant producer B. subtilis N3-1P attached onto the surface of fly ash acted as a robust and effective biocatalyst. Zeta potential analysis and scanning electron microscope (SEM) characterization were conducted to help unravel the biocatalyst formation. High-value biosurfactant products were then produced in an efficient and sustainable manner. Stimulation by a fly ash assisted biocatalyst on biosurfactant production was confirmed. The biosurfactant yield was boosted over ten times after 24 hours, at a fly ash dosage of 0.5%. The highest biosurfactant yield was achieved after five days, with a final productivity of 305 critical micelle dilution. The underlying mechanism of fly ash assisted biosurfactant production was tracked through it exerting an effect on the quorum sensing system. Fourier-transform infrared (FTIR) spectroscopy and matrix assisted laser desorption/ionization-time of flight (MALDI-TOF) analysis demonstrated that the final biosurfactant product belonged to the lipopeptides. This research output is expected to accelerate the development of more effective bioreactors, and make a continuous contribution to high-value product generation and waste reduction. Biosurfactants have been well recognized as an environmentally friendly alternative to chemical surfactants.![]()
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Affiliation(s)
- Zhiwen Zhu
- NRPOP Laboratory
- Faculty of Engineering and Applied Science
- Memorial University
- St. John's
- Canada
| | - Baiyu Zhang
- NRPOP Laboratory
- Faculty of Engineering and Applied Science
- Memorial University
- St. John's
- Canada
| | - Bing Chen
- NRPOP Laboratory
- Faculty of Engineering and Applied Science
- Memorial University
- St. John's
- Canada
| | - Jingjing Ling
- NRPOP Laboratory
- Faculty of Engineering and Applied Science
- Memorial University
- St. John's
- Canada
| | - Qinghong Cai
- Biotechnology Research Institute of the National Research Council of Canada
- Montreal
- Canada
- Department of Natural Resource Sciences
- Faculty of Agricultural and Environmental Sciences
| | - Tahir Husain
- NRPOP Laboratory
- Faculty of Engineering and Applied Science
- Memorial University
- St. John's
- Canada
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63
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Wang J, Guo R, Wang W, Ma G, Li S. Insight into the surfactin production of Bacillus velezensis B006 through metabolomics analysis. ACTA ACUST UNITED AC 2018; 45:1033-1044. [PMID: 30203399 DOI: 10.1007/s10295-018-2076-7] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/27/2018] [Accepted: 08/30/2018] [Indexed: 11/25/2022]
Abstract
Abstract
Bacillus velezensis B006 is a biocontrol agent which functions through effective colonization and surfactin production. To reveal the surfactin-producing mechanism, gas chromatography–mass spectrometry based untargeted metabolomics was performed to compare the metabolite profiles of strain B006 grown in industrial media M3 and M4. Based on the statistical and pathway topology analyses, a total of 31 metabolites with a fold change of less than − 1.0 were screened as the significantly altered metabolites, which distributed in 15 metabolic pathways. Fourteen amino acids involving in the metabolisms of alanine/aspartate/glutamate, glycine/serine/threonine, arginine/proline, glutathione/cysteine/methionine and valine/leucine/isoleucine as well as succinic acid in TCA cycle were identified to be the hub metabolites. Aminoacyl-tRNA biosynthesis, glycerolipid metabolism, and pantothenate/CoA biosynthesis also contributed to surfactin production. To the best of our knowledge, this study is the first to investigate the metabolic pathways of B. velezensis on surfactin production, and will benefit the optimization of commercial fermentation for higher surfactin yield.
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Affiliation(s)
- Junqiang Wang
- grid.464356.6 Institute of Plant Protection, Chinese Academy of Agricultural Sciences No. 2 Yuanmingyuan West Road 100193 Beijing China
- Jiangsu Frey Agrochemicals Co. Ltd 222005 Lianyungang Jiangsu China
| | - Rongjun Guo
- grid.464356.6 Institute of Plant Protection, Chinese Academy of Agricultural Sciences No. 2 Yuanmingyuan West Road 100193 Beijing China
| | - Wenchao Wang
- Shanghai ProfLeader Biotech Co. Ltd 200231 Shanghai China
| | - Guizhen Ma
- 0000 0004 1800 0658 grid.443480.f School of Chemical Engineering Huaihai Institute of Technology 222005 Lianyungang Jiangsu China
| | - Shidong Li
- grid.464356.6 Institute of Plant Protection, Chinese Academy of Agricultural Sciences No. 2 Yuanmingyuan West Road 100193 Beijing China
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64
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Wu Q, Zhi Y, Xu Y. Systematically engineering the biosynthesis of a green biosurfactant surfactin by Bacillus subtilis 168. Metab Eng 2018; 52:87-97. [PMID: 30453038 DOI: 10.1016/j.ymben.2018.11.004] [Citation(s) in RCA: 98] [Impact Index Per Article: 16.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/14/2018] [Accepted: 11/14/2018] [Indexed: 11/24/2022]
Abstract
The biosynthesis of surfactin has attracted broad interest; however, there is a bottleneck in its low yield in wild strains and the ability to engineer Bacillus producers. Because the key metabolic mechanisms in the surfactin synthesis pathway remain unclear, genetic engineering approaches are all ending up with a single or a few gene modifications. The aim of this study is to develop a systematic engineering approach to improve the biosynthesis of surfactin. First, we restored surfactin biosynthetic activity by integrating a complete sfp gene into the nonproducing Bacillus subtilis 168 strain and obtained a surfactin titer of 0.4 g/l. Second, we reduced competition by deleting biofilm formation-related genes and nonribosomal peptide synthetases/polyketide synthase pathways (3.8% of the total genome), which increased the surfactin titer by 3.3-fold. Third, we improved cellular tolerance to surfactin by overexpressing potential self-resistance-associated proteins, which further increased the surfactin titer by 8.5-fold. Fourth, we increased the supply of precursor branched-chain fatty acids by engineering the branched-chain fatty acid biosynthesis pathway, resulting in an increase of the surfactin titer to 8.5 g/l (a 20.3-fold increase). Finally, due to the preference of the glycolytic pathway for cell growth, we diverted precursor acetyl-CoA away from cell growth to surfactin biosynthesis by enhancing the transcription of srfA. The final surfactin titer increased to 12.8 g/l, with a yield of 65.0 mmol/mol sucrose (42% of the theoretical yield) in the metabolically engineered strain. To the best of our knowledge, this is the highest titer and yield that has been reported. This study may pave the way for the commercial production of green surfactin. More broadly, our work presents another successful example of the modularization of metabolic pathways for improving titer and yield in biotechnological production.
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Affiliation(s)
- Qun Wu
- Key Laboratory of Industrial Biotechnology of Ministry of Education, State Key Laboratory of Food Science and Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, China; Suqian Industrial Technology Research Institute of Jiangnan University, Suqian 223800, China
| | - Yan Zhi
- Key Laboratory of Industrial Biotechnology of Ministry of Education, State Key Laboratory of Food Science and Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, China
| | - Yan Xu
- Key Laboratory of Industrial Biotechnology of Ministry of Education, State Key Laboratory of Food Science and Technology, School of Biotechnology, Jiangnan University, Wuxi 214122, China.
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65
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Goswami G, Panda D, Samanta R, Boro RC, Modi MK, Bujarbaruah KM, Barooah M. Bacillus megaterium adapts to acid stress condition through a network of genes: Insight from a genome-wide transcriptome analysis. Sci Rep 2018; 8:16105. [PMID: 30382109 PMCID: PMC6208408 DOI: 10.1038/s41598-018-34221-0] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2018] [Accepted: 10/05/2018] [Indexed: 11/18/2022] Open
Abstract
RNA-seq analysis of B. megaterium exposed to pH 7.0 and pH 4.5 showed differential expression of 207 genes related to several processes. Among the 207 genes, 11 genes displayed increased transcription exclusively in pH 4.5. Exposure to pH 4.5 induced the expression of genes related to maintenance of cell integrity, pH homeostasis, alternative energy generation and modification of metabolic processes. Metabolic processes like pentose phosphate pathway, fatty acid biosynthesis, cysteine and methionine metabolism and synthesis of arginine and proline were remodeled during acid stress. Genes associated with oxidative stress and osmotic stress were up-regulated at pH 4.5 indicating a link between acid stress and other stresses. Acid stress also induced expression of genes that encoded general stress-responsive proteins as well as several hypothetical proteins. Our study indicates that a network of genes aid B. megaterium G18 to adapt and survive in acid stress condition.
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Affiliation(s)
- Gunajit Goswami
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, 785013, India.,Department of Life-Sciences, Dibrugarh University, Dibrugarh, 786004, Assam, India
| | - Debashis Panda
- Distributed Information Centre, Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, 785013, India
| | - Ramkrishna Samanta
- Department of Life-Sciences, Dibrugarh University, Dibrugarh, 786004, Assam, India
| | - Robin Chandra Boro
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, 785013, India
| | - Mahendra Kumar Modi
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, 785013, India.,Distributed Information Centre, Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, 785013, India
| | - Kamal Malla Bujarbaruah
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, 785013, India
| | - Madhumita Barooah
- Department of Agricultural Biotechnology, Assam Agricultural University, Jorhat, 785013, India.
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66
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Ogawara H. Comparison of Strategies to Overcome Drug Resistance: Learning from Various Kingdoms. Molecules 2018; 23:E1476. [PMID: 29912169 PMCID: PMC6100412 DOI: 10.3390/molecules23061476] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2018] [Revised: 06/13/2018] [Accepted: 06/15/2018] [Indexed: 11/16/2022] Open
Abstract
Drug resistance, especially antibiotic resistance, is a growing threat to human health. To overcome this problem, it is significant to know precisely the mechanisms of drug resistance and/or self-resistance in various kingdoms, from bacteria through plants to animals, once more. This review compares the molecular mechanisms of the resistance against phycotoxins, toxins from marine and terrestrial animals, plants and fungi, and antibiotics. The results reveal that each kingdom possesses the characteristic features. The main mechanisms in each kingdom are transporters/efflux pumps in phycotoxins, mutation and modification of targets and sequestration in marine and terrestrial animal toxins, ABC transporters and sequestration in plant toxins, transporters in fungal toxins, and various or mixed mechanisms in antibiotics. Antibiotic producers in particular make tremendous efforts for avoiding suicide, and are more flexible and adaptable to the changes of environments. With these features in mind, potential alternative strategies to overcome these resistance problems are discussed. This paper will provide clues for solving the issues of drug resistance.
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Affiliation(s)
- Hiroshi Ogawara
- HO Bio Institute, Yushima-2, Bunkyo-ku, Tokyo 113-0034, Japan.
- Department of Biochemistry, Meiji Pharmaceutical University, Noshio-2, Kiyose, Tokyo 204-8588, Japan.
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67
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Belbahri L, Chenari Bouket A, Rekik I, Alenezi FN, Vallat A, Luptakova L, Petrovova E, Oszako T, Cherrad S, Vacher S, Rateb ME. Comparative Genomics of Bacillus amyloliquefaciens Strains Reveals a Core Genome with Traits for Habitat Adaptation and a Secondary Metabolites Rich Accessory Genome. Front Microbiol 2017; 8:1438. [PMID: 28824571 PMCID: PMC5541019 DOI: 10.3389/fmicb.2017.01438] [Citation(s) in RCA: 50] [Impact Index Per Article: 7.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2017] [Accepted: 07/17/2017] [Indexed: 12/04/2022] Open
Abstract
The Gram positive, non-pathogenic endospore-forming soil inhabiting prokaryote Bacillus amyloliquefaciens is a plant growth-promoting rhizobacterium. Bacillus amyloliquefaciens processes wide biocontrol abilities and numerous strains have been reported to suppress diverse bacterial, fungal and fungal-like pathogens. Knowledge about strain level biocontrol abilities is warranted to translate this knowledge into developing more efficient biocontrol agents and bio-fertilizers. Ever-expanding genome studies of B. amyloliquefaciens are showing tremendous increase in strain-specific new secondary metabolite clusters which play key roles in the suppression of pathogens and plant growth promotion. In this report, we have used genome mining of all sequenced B. amyloliquefaciens genomes to highlight species boundaries, the diverse strategies used by different strains to promote plant growth and the diversity of their secondary metabolites. Genome composition of the targeted strains suggest regions of genomic plasticity that shape the structure and function of these genomes and govern strain adaptation to different niches. Our results indicated that B. amyloliquefaciens: (i) suffer taxonomic imprecision that blurs the debate over inter-strain genome diversity and dynamics, (ii) have diverse strategies to promote plant growth and development, (iii) have an unlocked, yet to be delimited impressive arsenal of secondary metabolites and products, (iv) have large number of so-called orphan gene clusters, i.e., biosynthetic clusters for which the corresponding metabolites are yet unknown, and (v) have a dynamic pan genome with a secondary metabolite rich accessory genome.
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Affiliation(s)
- Lassaad Belbahri
- Laboratory of Soil Biology, University of NeuchatelNeuchatel, Switzerland.,NextBiotechAgareb, Tunisia
| | - Ali Chenari Bouket
- NextBiotechAgareb, Tunisia.,Graduate School of Life and Environmental Sciences, Osaka Prefecture UniversitySakai, Japan.,Young Researchers and Elite Club, Tabriz Branch, Islamic Azad UniversityTabriz, Iran
| | | | | | - Armelle Vallat
- Neuchâtel Platform of Analytical Chemistry, Institute of Chemistry, University of NeuchâtelNeuchâtel, Switzerland
| | - Lenka Luptakova
- NextBiotechAgareb, Tunisia.,Department of Biology and Genetics, Institute of Biology, Zoology and Radiobiology, University of Veterinary Medicine and PharmacyKosice, Slovakia
| | - Eva Petrovova
- Institute of Anatomy, University of Veterinary Medicine and PharmacyKosice, Slovakia
| | | | | | | | - Mostafa E Rateb
- School of Science and Sport, University of the West of ScotlandPaisley, United Kingdom
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68
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Zhi Y, Wu Q, Xu Y. Production of surfactin from waste distillers' grains by co-culture fermentation of two Bacillus amyloliquefaciens strains. BIORESOURCE TECHNOLOGY 2017; 235:96-103. [PMID: 28365354 DOI: 10.1016/j.biortech.2017.03.090] [Citation(s) in RCA: 55] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2017] [Revised: 03/15/2017] [Accepted: 03/16/2017] [Indexed: 05/12/2023]
Abstract
Distillers' grains (DGS), the main waste by-products of Chinese liquor industry, were used as substrate for surfactin production. Bacillus amyloliquefaciens MT45 could grow with DGS as sole carbon source to produce 1.04g/l surfactin. However, low amylase activity of MT45 limited sugar supply and the subsequent surfactin production. Therefore, MT45 was co-cultured with Bacillus strains that exhibited remarkable hydrolases activities. Surfactin yield increased by 50% when MT45 was co-cultured with B. amyloliquefaciens X82 that showed no product inhibition effect and did not develop extracellular matrix. The inoculation ratio of X82 greatly influenced the sugar supply, cellular growth, and surfactin production of the co-culture fermentation. Maximum surfactin titration (3.4g/l) was obtained when MT45 and X82 were co-cultured with inoculation ratio at 1:0.5, using 200g/l DGS. This work highlights the feasibility of using industrial waste DGS as promising feedstocks to produce value-added surfactin by co-culture fermentation.
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Affiliation(s)
- Yan Zhi
- State Key Laboratory of Food Science and Technology, The Key Laboratory of Industrial Biotechnology, Synergetic Innovation Centre of Food Safety and Nutrition, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
| | - Qun Wu
- State Key Laboratory of Food Science and Technology, The Key Laboratory of Industrial Biotechnology, Synergetic Innovation Centre of Food Safety and Nutrition, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China
| | - Yan Xu
- State Key Laboratory of Food Science and Technology, The Key Laboratory of Industrial Biotechnology, Synergetic Innovation Centre of Food Safety and Nutrition, School of Biotechnology, Jiangnan University, 1800 Lihu Avenue, Wuxi 214122, China.
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