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Sun Y, Su X, Zhao L, Sun T, Liu W. Carbon metabolism of a novel isolate from Lacticaseibacillus rhamnosus Probio-M9 derived through space mutant. J Appl Microbiol 2024; 135:lxae205. [PMID: 39152088 DOI: 10.1093/jambio/lxae205] [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: 10/19/2023] [Revised: 07/07/2024] [Accepted: 08/15/2024] [Indexed: 08/19/2024]
Abstract
AIMS Carbon source is a necessary nutrient for bacterial strain growth. In industrial production, the cost of using different carbon sources varies greatly. Moreover, the complex environment in space may cause metabolic a series of changes in the strain, and this method has been successfully applied in some basic research. To date, space mutagenesis is still limited number of studies, particularly in carbon metabolism of probiotics. METHODS AND RESULTS HG-R7970-41 was isolated from bacterium suspension (Probio-M9) after space flight, which can produce capsular polysaccharide after space mutagenesis. Phenotype Microarray (PM) was used to evaluated the metabolism of HG-R7970-41 in 190 single carbon sources. RNA sequencing and total protein identification of two strains revealed their different carbon metabolism mechanisms. PM results demonstrated the metabolism of 10 carbon sources were different between Probio-M9 and HG-R7970-41. Transcriptomic and proteomic analyses revealed that this change in carbon metabolism of HG-R7970-41 mainly related to changes in phosphorylation and the glycolysis pathway. Based on the metabolic mechanism of different carbon sources and related gene cluster analysis, we found that the final metabolic activities of HG-R7970-41 and Probio-M9 were mainly regulated by PTS-specific membrane embedded permease, carbohydrate kinase and two rate-limiting enzymes (phosphofructokinase and pyruvate kinase) in the glycolysis pathway. The expanded culture test also confirmed that HG-R7970-41 had different metabolic characteristics from original strain. CONCLUSIONS These results suggested that space environment could change carbon metabolism of Probio-M9. The new isolate (HG-R7970-41) showed a different carbon metabolism pattern from the original strain mainly by the regulation of two rate-limiting enzymes.
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Affiliation(s)
- Yue Sun
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs; Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, 010018, China
- College of Food Science and Technology, Wuhan Business University, Wuhan, Hubei province, 430056, China
| | - Xin Su
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs; Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, 010018, China
| | - Lixia Zhao
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs; Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, 010018, China
| | - Tiansong Sun
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs; Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, 010018, China
| | - Wenjun Liu
- Inner Mongolia Key Laboratory of Dairy Biotechnology and Engineering; Key Laboratory of Dairy Products Processing, Ministry of Agriculture and Rural Affairs; Key Laboratory of Dairy Biotechnology and Engineering, Ministry of Education, Inner Mongolia Agricultural University, Hohhot, Inner Mongolia, 010018, China
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2
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Zhou D, Huang J, Zheng H, Liu Y, Zhu S, Du Y. Insight into Fructose-to-Sucrose Ratio as the Potential Target of Urinalysis in Bladder Cancer. Metabolites 2024; 14:345. [PMID: 38921479 PMCID: PMC11205578 DOI: 10.3390/metabo14060345] [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: 03/25/2024] [Revised: 05/20/2024] [Accepted: 06/17/2024] [Indexed: 06/27/2024] Open
Abstract
Bladder cancer usually has been diagnosed in elderly patients as it stays asymptomatic until it presents. Current detection methods for bladder cancer cannot be considered as an adequate screening strategy due to their high invasiveness and low sensitivity. However, there remains uncertainty about targets with high sensitivity and specificity for non-invasive bladder cancer examination. Our study aims to investigate the actionable non-invasive screening biomarkers in bladder cancer. Here, we employed scRNA-seq to explore the crucial biological processes for bladder cancer development. We then utilized bidirectional Mendelian randomization (MR) analysis to explore the bidirectional causal relationship between ATP-associated metabolites in urine and bladder cancer. Lastly, we used a BBN-induced mouse model of bladder cancer to validate the crucial gene identified by scRNA-seq and MR analysis. We found that (1) the ATP metabolism process plays a critical role in bladder cancer development; (2) there is a bidirectional and negative causal relationship between fructose-to-sucrose ratio in urine and the risk of bladder cancer; and (3) the higher expression of TPI1, a critical gene in the fructose metabolism pathway, was validated in BBN-induced bladder tumors. Our results reveal that fructose-to-sucrose ratio can serve as a potential target of urinalysis in bladder cancer.
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Affiliation(s)
- Dewang Zhou
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong, Shenzhen 518172, China;
| | - Jianxu Huang
- Shantou University Medical College, Shantou University, Shantou 515063, China;
| | - Haoxiang Zheng
- Department of Urology, Medical School, Shenzhen University, Shenzhen 518116, China;
| | - Yujun Liu
- Medical School, Anhui University of Science and Technology, Huainan 232001, China;
| | - Shimao Zhu
- Department of Urology, Medical School, Shenzhen University, Shenzhen 518116, China;
| | - Yang Du
- Kobilka Institute of Innovative Drug Discovery, School of Medicine, The Chinese University of Hong Kong, Shenzhen 518172, China;
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3
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Chen Q, Ren R, Sun Y, Xu J, Yang H, Li X, Xiao Y, Li J, Lyu W. The combination of metagenome and metabolome to compare the differential effects and mechanisms of fructose and sucrose on the metabolic disorders and gut microbiota in vitro and in vivo. Food Funct 2023. [PMID: 37470119 DOI: 10.1039/d3fo02246c] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/21/2023]
Abstract
Sucrose and fructose are the most commonly used sweeteners in the modern food industry, but there are few comparative studies on the mechanisms by which fructose and sucrose affect host health. The aim of the present study was to explain the different effects of fructose and sucrose on host metabolism from the perspective of gut microbiota. Mice were fed for 16 weeks with normal drinking water (CON), 30% fructose drinking water (CF) and 30% sucrose drinking water (SUC). Compared with fructose treatment, sucrose caused significantly higher weight gain, epididymal fat deposition, hepatic steatosis, and jejunum histological injury. Sucrose increased the abundance of LPS-producing bacteria which was positively correlated with obesity traits, while fructose increased the abundance of Lactobacillus. An in vitro fermentation experiment also showed that fructose increased the abundance of Lactobacillus, while sucrose increased the abundance of Klebsiella and Escherichia. In addition, combined with microbial functional analysis and metabolomics data, fructose led to the enhancement of carbohydrate metabolism and TCA cycle capacity, and increased the production of glutamate. The cross-cooperation network greatly influenced the microbiota (Klebsiella, Lactobacillus), metabolites (glutamate, fructose 1,6-biosphosphate, citric acid), and genes encoding enzymes (pyruvate kinase, 6-phosphofructokinase 1, fructokinase, lactate dehydrogenase, aconitate hydratase, isocitrate dehydrogenase 3), suggesting that they may be the key differential factors in the process of fructose and sucrose catabolism. Therefore, the changes in gut microbiome mediated by fructose and sucrose are important reasons for their differential effects on host health and metabolism.
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Affiliation(s)
- Qu Chen
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Ruochen Ren
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Yue Sun
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Jing Xu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Hua Yang
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Xiaoqiong Li
- Institute of Food Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Yingping Xiao
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Jinjun Li
- Institute of Food Sciences, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
| | - Wentao Lyu
- State Key Laboratory for Managing Biotic and Chemical Threats to the Quality and Safety of Agro-products, Institute of Agro-product Safety and Nutrition, Zhejiang Academy of Agricultural Sciences, Hangzhou, China.
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Alexandri M, Hübner D, Schneider R, Fröhling A, Venus J. Towards efficient production of highly optically pure d-lactic acid from lignocellulosic hydrolysates using newly isolated lactic acid bacteria. N Biotechnol 2022; 72:1-10. [PMID: 35981701 DOI: 10.1016/j.nbt.2022.08.003] [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: 05/24/2022] [Revised: 08/05/2022] [Accepted: 08/11/2022] [Indexed: 12/14/2022]
Abstract
This study presents the production of D-lactic acid with high enantiomeric purity using lignocellulosic hydrolysates from newly isolated lactic acid bacterial (LAB) strains. Six strains, 4 heterofermentative and 2 homofermentative, were investigated for their ability to grow and produce lactic acid on sugar beet pulp (SBP) hydrolysates, containing a mixture of hexose and pentose sugars. Among the strains tested, three were isolates designated as A250, A257 and A15, all of which belonged to the genus Leuconostoc. Only strain A250 could be reliably identified as Leuconostoc pseudomesenteroides based on cluster analysis of Maldi-ToF spectra. All strains produced D-lactic acid in the presence of SBP hydrolysates, but with varying optical purities. The homofermentative strains achieved higher D-lactic acid optical purities, but without assimilating the pentose sugars. Co-cultivation of the homofermentative strain Lactobacillus coryniformis subsp. torquens DSM 20005 together with the heterofermentative isolate A250 led to the production of 21.7 g/L D-lactic acid with 99.3 % optical purity. This strategy enabled the complete sugar utilization of the substrate. Nanofiltration of the SBP hydrolysate enhanced the enantiomeric purity of the D-lactic acid produced from the isolates A250 and A15 by about 5 %. The highest D-lactic acid concentration (40 g/L) was achieved in fed-batch cultures of A250 isolate with nanofiltered SBP, where optical purity was 99.4 %. The results of this study underline the feasibility of a novel isolate as an efficient D-lactic acid producer using lignocellulosic hydrolysates.
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Affiliation(s)
- Maria Alexandri
- Leibniz Institute for Agricultural Engineering and Bioecomomy (ATB), Max-Eyth Allee 100, Potsdam, Germany; Ionian University, Department of Food Science and Technology, Argostoli 28100, Kefalonia, Greece
| | - Dennis Hübner
- Leibniz Institute for Agricultural Engineering and Bioecomomy (ATB), Max-Eyth Allee 100, Potsdam, Germany
| | - Roland Schneider
- Leibniz Institute for Agricultural Engineering and Bioecomomy (ATB), Max-Eyth Allee 100, Potsdam, Germany
| | - Antje Fröhling
- Leibniz Institute for Agricultural Engineering and Bioecomomy (ATB), Max-Eyth Allee 100, Potsdam, Germany
| | - Joachim Venus
- Leibniz Institute for Agricultural Engineering and Bioecomomy (ATB), Max-Eyth Allee 100, Potsdam, Germany.
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5
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Wang Y, Zhang C, Liu F, Jin Z, Xia X. Ecological succession and functional characteristics of lactic acid bacteria in traditional fermented foods. Crit Rev Food Sci Nutr 2022; 63:5841-5855. [PMID: 35014569 DOI: 10.1080/10408398.2021.2025035] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Fermented foods are important parts of traditional food culture with a long history worldwide. Abundant nutritional materials and open fermentation contribute to the diversity of microorganisms, resulting in unique product quality and flavor. Lactic acid bacteria (LAB), as important part of traditional fermented foods, play a decisive role in the quality and safety of fermented foods. Reproduction and metabolic of microorganisms drive the food fermentation, and microbial interaction plays a major role in the fermentation process. Nowadays, LAB have attracted considerable interest due to their potentialities to add functional properties to certain foods or as supplements along with the research of gut microbiome. This review focuses on the characteristics of diversity and variability of LAB in traditional fermented foods, and describes the principal mechanisms involved in the flavor formation dominated by LAB. Moreover, microbial interactions and their mechanisms in fermented foods are presented. They provide a theoretical basis for exploiting LAB in fermented foods and improving the quality of traditional fermented foods. The traditional fermented food industry should face the challenge of equipment automation, green manufacturing, and quality control and safety in the production.
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Affiliation(s)
- Yingyu Wang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, China
| | - Chenhao Zhang
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, China
| | | | - Zhengyu Jin
- State Key Laboratory of Food Science and Technology, School of Food Science and Technology, Jiangnan University, WuXi, China
| | - Xiaole Xia
- The Key Laboratory of Industrial Biotechnology, Ministry of Education, School of Biotechnology, Jiangnan University, WuXi, China
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Sugino KY, Mandala A, Janssen RC, Gurung S, Trammell M, Day MW, Brush RS, Papin JF, Dyer DW, Agbaga MP, Friedman JE, Castillo-Castrejon M, Jonscher KR, Myers DA. Western diet-induced shifts in the maternal microbiome are associated with altered microRNA expression in baboon placenta and fetal liver. FRONTIERS IN CLINICAL DIABETES AND HEALTHCARE 2022; 3:945768. [PMID: 36935840 PMCID: PMC10012127 DOI: 10.3389/fcdhc.2022.945768] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
Maternal consumption of a high-fat, Western-style diet (WD) disrupts the maternal/infant microbiome and contributes to developmental programming of the immune system and nonalcoholic fatty liver disease (NAFLD) in the offspring. Epigenetic changes, including non-coding miRNAs in the fetus and/or placenta may also underlie this risk. We previously showed that obese nonhuman primates fed a WD during pregnancy results in the loss of beneficial maternal gut microbes and dysregulation of cellular metabolism and mitochondrial dysfunction in the fetal liver, leading to a perturbed postnatal immune response with accelerated NAFLD in juvenile offspring. Here, we investigated associations between WD-induced maternal metabolic and microbiome changes, in the absence of obesity, and miRNA and gene expression changes in the placenta and fetal liver. After ~8-11 months of WD feeding, dams were similar in body weight but exhibited mild, systemic inflammation (elevated CRP and neutrophil count) and dyslipidemia (increased triglycerides and cholesterol) compared with dams fed a control diet. The maternal gut microbiome was mainly comprised of Lactobacillales and Clostridiales, with significantly decreased alpha diversity (P = 0.0163) in WD-fed dams but no community-wide differences (P = 0.26). At 0.9 gestation, mRNA expression of IL6 and TNF in maternal WD (mWD) exposed placentas trended higher, while increased triglycerides, expression of pro-inflammatory CCR2, and histological evidence for fibrosis were found in mWD-exposed fetal livers. In the mWD-exposed fetus, hepatic expression levels of miR-204-5p and miR-145-3p were significantly downregulated, whereas in mWD-exposed placentas, miR-182-5p and miR-183-5p were significantly decreased. Notably, miR-1285-3p expression in the liver and miR-183-5p in the placenta were significantly associated with inflammation and lipid synthesis pathway genes, respectively. Blautia and Ruminococcus were significantly associated with miR-122-5p in liver, while Coriobacteriaceae and Prevotellaceae were strongly associated with miR-1285-3p in the placenta; both miRNAs are implicated in pathways mediating postnatal growth and obesity. Our findings demonstrate that mWD shifts the maternal microbiome, lipid metabolism, and inflammation prior to obesity and are associated with epigenetic changes in the placenta and fetal liver. These changes may underlie inflammation, oxidative stress, and fibrosis patterns that drive NAFLD and metabolic disease risk in the next generation.
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Affiliation(s)
- Kameron Y. Sugino
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Ashok Mandala
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Rachel C. Janssen
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Sunam Gurung
- Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - MaJoi Trammell
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Michael W. Day
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Richard S. Brush
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - James F. Papin
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - David W. Dyer
- Department of Microbiology and Immunology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Martin-Paul Agbaga
- Department of Ophthalmology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Department of Cell Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Jacob E. Friedman
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Department of Physiology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Marisol Castillo-Castrejon
- Department of Pathology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Stephenson Cancer Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
| | - Karen R. Jonscher
- Harold Hamm Diabetes Center, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- Department of Biochemistry and Molecular Biology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
- CORRESPONDENCE: Karen R. Jonscher,
| | - Dean A. Myers
- Department of Obstetrics and Gynecology, University of Oklahoma Health Sciences Center, Oklahoma City, OK, United States
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7
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Wang Q, Yang L, Feng K, Li H, Deng Z, Liu J. Promote lactic acid production from food waste fermentation using biogas slurry recirculation. BIORESOURCE TECHNOLOGY 2021; 337:125393. [PMID: 34120058 DOI: 10.1016/j.biortech.2021.125393] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/12/2021] [Revised: 06/04/2021] [Accepted: 06/05/2021] [Indexed: 06/12/2023]
Abstract
It is a promising method to recover lactic acid from food waste (FW) fermentation, but the bottleneck problem is the low yield when using mixed inoculation. In this study, laboratorial biogas slurry (LBS) and industrial biogas slurry (IBS) were used as the additive in semi-continuous FW fermentation, aiming to promote the production of lactic acid. According to the research results, the addition of LBS or IBS promoted the production of lactic acid significantly from FW, especially carbohydrate, because it increased the pH values, maintained low OPR levels, and increased microbial number and diversity in the fermentation systems. IBS performed better than LBS because of higher pH, more diverse microbial community and more functional microorganisms. The best ratio of IBS to feedstock was 0.2, and the lactic acid yield reached 0.42 g/gVSadded. An excessively high dose would alter the fermentation pathways, reduce the ratio of lactic acid.
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Affiliation(s)
- Qiao Wang
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Luxin Yang
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Kai Feng
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Huan Li
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
| | - Zhou Deng
- Shenzhen Lisai Environmental Technology Co, Ltd., Shenzhen 518055, China
| | - Jianguo Liu
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China; School of Environment, Tsinghua University, Beijing 100084, China
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8
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Wang Q, Li H, Feng K. Effect of honeycomb, granular, and powder activated carbon additives on continuous lactic acid fermentation of complex food waste with mixed inoculation. J Biosci Bioeng 2021; 131:655-662. [PMID: 33775543 DOI: 10.1016/j.jbiosc.2021.02.009] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/04/2020] [Revised: 02/25/2021] [Accepted: 02/26/2021] [Indexed: 01/31/2023]
Abstract
To accelerate and stabilize lactic acid fermentation from food waste, three types of activated carbon, including honeycomb activated carbon, granular activated carbon, and powder activated carbon, were tested as additives in continuous food waste fermentation processes. The results showed that carbohydrate was the primary substrate for lactic acid production, but its conversion reached a high, stable level after a long period of microbial acclimation in the control system. Activated carbon, especially honeycomb activated carbon accelerated the stabilization of lactic acid fermentation and enhanced the tolerance of fermentation systems to a hostile and fluctuating environment. The addition of activated carbon increased the oxidation-reduction potential to approximately 100 mV and altered the microbial communities. Homolactic fermentation bacteria were dominant in all the systems, and the honeycomb activated carbon addition stimulated the growth of unclassified Lactobacillus and immobilized Lactobacillus panis with strong carbohydrate metabolism. In addition, powder activated carbon enhanced the degradation of protein due to the multiplying Pseudomonas. At the stable stage, the organic conversion rates were close in the control system and the systems with the activated carbon addition, and the lactic acid concentrations in these systems remained at 8000-10,000 mg/L. Considering the cost of the additives, honeycomb activated carbon is a good choice to stabilize lactic acid production from food waste.
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Affiliation(s)
- Qiao Wang
- Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Huan Li
- Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
| | - Kai Feng
- Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
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9
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Wang Q, Feng K, Li H. Nano iron materials enhance food waste fermentation. BIORESOURCE TECHNOLOGY 2020; 315:123804. [PMID: 32673984 DOI: 10.1016/j.biortech.2020.123804] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2020] [Revised: 07/03/2020] [Accepted: 07/04/2020] [Indexed: 06/11/2023]
Abstract
Anaerobic fermentation can produce valuable chemicals from food waste, such as butyric acid, lactic acid, and ethanol. Three nano iron materials, i.e. zero-valence iron (nZVI), ferric oxide (nFO), and magnetite (nM), were tested to improve food waste fermentation with mixed inoculation. nZVI and nFO enhanced the dissolution and conversion of carbohydrate to lactate, dependent on different mechanisms, while nM had almost no effects due to its aggregation at high doses. nZVI alleviated the drop of pH, kept the ORP at an anaerobic level, increased functional enzymes, and resulted in a high hydrolysis rate of 45% and lactic acid yield of 0.16 g/g VSfed at the dose of 500 mg/(Lfed·d). nFO increased the ORP to 100 mV, stimulated the enrichment of Pseudomonas, and increased the abundance of Lactobacillus_panis, leading to hydrolysis rate of 47% and lactic acid yield of 0.19 g/gVSfed at the dose of 200 mg/(Lfed·d).
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Affiliation(s)
- Qiao Wang
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Kai Feng
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China
| | - Huan Li
- Tsinghua Shenzhen International Graduate School, Tsinghua University, Shenzhen 518055, China.
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Rogalski E, Ehrmann MA, Vogel RF. Intraspecies diversity and genome-phenotype-associations in Fructilactobacillus sanfranciscensis. Microbiol Res 2020; 243:126625. [PMID: 33129664 DOI: 10.1016/j.micres.2020.126625] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Revised: 09/25/2020] [Accepted: 10/09/2020] [Indexed: 02/04/2023]
Abstract
In this study the intraspecies diversity of Fructilactobacillus (F.) sanfranciscensis (formerly Lactobacillus sanfranciscensis) was characterized by comparative genomics supported by physiological data. Twenty-four strains of F. sanfranciscensis were analyzed and sorted into six different genomic clusters. The core genome comprised only 43,14 % of the pan genome, i.e. 0.87 Mbp of 2.04 Mbp. The main annotated genomic differences reside in maltose, fructose and sucrose as well as nucleotide metabolism, use of electron acceptors, and exopolysacchride formation. Furthermore, all strains are well equipped to cope with oxidative stress via NADH oxidase and a distinct thiol metabolism. Only ten of 24 genomes contain two maltose phosphorylase genes (mapA and mapB). In F. sanfranciscensis TMW 1.897 only mapA was found. All strains except those from genomic cluster 2 contained the mannitol dehydrogenase and should therefore be able to use fructose as external electron acceptor. Moreover, six strains were able to grow on fructose as sole carbon source, as they contained a functional fructokinase gene. No growth was observed on pentoses, i.e. xylose, arabinose or ribose, as sole carbon source. This can be referred to the absence of ribose pyranase rbsD in all genomes, and absence of or mutations in numerous other genes, which are essential for arabinose and xylose metabolism. Seven strains were able to produce exopolysaccharides (EPS) from sucrose. In addition, the strains containing levS were able to grow on sucrose as sole carbon source. Strains of one cluster exhibit auxotrophies for purine nucleotides. The physiological and genomic analyses suggest that the biodiversity of F. sanfranciscensis is larger than anticipated. Consequently, "original" habitats and lifestyles of F. sanfranciscensis may vary but can generally be referred to an adaptation to sugary (maltose/sucrose/fructose-rich) and aerobic environments as found in plants and insects. It can dominate sourdoughs as a result of reductive evolution and cooperation with fructose-delivering, acetate-tolerant yeasts.
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Affiliation(s)
- Esther Rogalski
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München, Freising, Germany
| | - Matthias A Ehrmann
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München, Freising, Germany
| | - Rudi F Vogel
- Lehrstuhl für Technische Mikrobiologie, Technische Universität München, Freising, Germany.
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11
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Robertsson C, Svensäter G, Blum Z, Wickström C. Intracellular Ser/Thr/Tyr phosphoproteome of the oral commensal Streptococcus gordonii DL1. BMC Microbiol 2020; 20:280. [PMID: 32928109 PMCID: PMC7488673 DOI: 10.1186/s12866-020-01944-y] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/26/2020] [Accepted: 08/11/2020] [Indexed: 12/28/2022] Open
Abstract
Background To respond and adapt to environmental challenges, prokaryotes regulate cellular processes rapidly and reversibly through protein phosphorylation and dephosphorylation. This study investigates the intracellular proteome and Ser/Thr/Tyr phosphoproteome of the oral commensal Streptococcus gordonii. Intracellular proteins from planktonic cells of S. gordonii DL1 were extracted and subjected to 2D-gel electrophoresis. Proteins in general were visualized using Coomassie Brilliant Blue and T-Rex staining. Phosphorylated proteins were visualized with Pro-Q Diamond Phosphoprotein Gel Stain. Proteins were identified by LC-MS/MS and sequence analysis. Results In total, sixty-one intracellular proteins were identified in S. gordonii DL1, many of which occurred at multiple isoelectric points. Nineteen of these proteins were present as one or more Ser/Thr/Tyr phosphorylated form. The identified phosphoproteins turned out to be involved in a variety of cellular processes. Conclusion Nineteen phosphoproteins involved in various cellular functions were identified in S. gordonii. This is the first time the global intracellular Ser/Thr/Tyr phosphorylation profile has been analysed in an oral streptococcus. Comparison with phosphoproteomes of other species from previous studies showed many similarities. Proteins that are consistently found in a phosphorylated state across several species and growth conditions may represent a core phosphoproteome profile shared by many bacteria.
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Affiliation(s)
- Carolina Robertsson
- Department of Oral Biology and Pathology, Faculty of Odontology, Malmö University, 20506, Malmö, Sweden.
| | - Gunnel Svensäter
- Department of Oral Biology and Pathology, Faculty of Odontology, Malmö University, 20506, Malmö, Sweden
| | - Zoltan Blum
- Department of Biomedical Science, Malmö University, 20506, Malmö, Sweden
| | - Claes Wickström
- Department of Oral Biology and Pathology, Faculty of Odontology, Malmö University, 20506, Malmö, Sweden
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12
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Alfano A, Perillo F, Fusco A, Savio V, Corsaro MM, Donnarumma G, Schiraldi C, Cimini D. Lactobacillus brevis CD2: Fermentation Strategies and Extracellular Metabolites Characterization. Probiotics Antimicrob Proteins 2020; 12:1542-1554. [PMID: 32279232 DOI: 10.1007/s12602-020-09651-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
Abstract
Functional foods and nutraceuticals frequently contain viable probiotic strains that, at certain titers, are considered to be responsible of beneficial effects on health. Recently, it was observed that secreted metabolites might play a key role in this respect, especially in immunomodulation. Exopolysaccharides produced by probiotics, for example, are used in the food, pharmaceutical, and biomedical fields, due to their unique properties. Lactobacillus brevis CD2 demonstrated the ability to inhibit oral pathogens causing mucositis and periodontal inflammation and to reduce Helycobacter pylori infections. Due to the lack of literature, for this strain, on the development of fermentation processes that can increase the titer of viable cells and associated metabolites to industrially attractive levels, different batch and fed-batch strategies were investigated in the present study. In particular, aeration was shown to improve the growth rate and the yields of lactic acid and biomass in batch cultures. The use of an exponential feeding profile in fed-batch experiments allowed to produce 9.3 ± 0.45 × 109 CFU/mL in 42 h of growth, corresponding to a 20-fold increase of viable cells compared with that obtained in aerated batch processes; moreover, also increased titers of exopolysaccharides and lactic acid (260 and 150%, respectively) were observed. A purification process based on ultrafiltration, charcoal treatment, and solvent precipitation was applied to partially purify secreted metabolites and separate them into two molecular weight fractions (above and below 10 kDa). Both fractions inhibited growth of the known gut pathogen, Salmonella typhimurium, demonstrating that lactic acid plays a major role in pathogen growth inhibition, which is however further enhanced by the presence of Lact. brevis CD2 exopolysaccharides. Finally, the EPS produced from Lact. brevis CD2 was characterized by NMR for the first time up to date.
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Affiliation(s)
- Alberto Alfano
- Department of Experimental Medicine, Section of Biotechnology Medical Histology and Molecular Biology, University of Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138, Naples, Italy
| | - Filomena Perillo
- Department of Experimental Medicine, Section of Biotechnology Medical Histology and Molecular Biology, University of Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138, Naples, Italy
| | - Alessandra Fusco
- Department of Experimental Medicine, Section of Microbiology and Clinical Microbiology, Università della Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138, Naples, Italy
| | - Vittoria Savio
- Department of Experimental Medicine, Section of Microbiology and Clinical Microbiology, Università della Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138, Naples, Italy
| | - Maria Michela Corsaro
- Department of Chemic1al Science, University Federico II, Complesso Universitario Monte S.Angelo, via Cintia 4, 80126, Naples, Italy
| | - Giovanna Donnarumma
- Department of Experimental Medicine, Section of Microbiology and Clinical Microbiology, Università della Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138, Naples, Italy
| | - Chiara Schiraldi
- Department of Experimental Medicine, Section of Biotechnology Medical Histology and Molecular Biology, University of Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138, Naples, Italy.
| | - Donatella Cimini
- Department of Experimental Medicine, Section of Biotechnology Medical Histology and Molecular Biology, University of Campania "Luigi Vanvitelli", via L. De Crecchio n 7, 80138, Naples, Italy.
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13
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Kristjansdottir T, Bosma EF, Branco Dos Santos F, Özdemir E, Herrgård MJ, França L, Ferreira B, Nielsen AT, Gudmundsson S. A metabolic reconstruction of Lactobacillus reuteri JCM 1112 and analysis of its potential as a cell factory. Microb Cell Fact 2019; 18:186. [PMID: 31665018 PMCID: PMC6821008 DOI: 10.1186/s12934-019-1229-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2019] [Accepted: 10/11/2019] [Indexed: 01/09/2023] Open
Abstract
Background Lactobacillus reuteri is a heterofermentative Lactic Acid Bacterium (LAB) that is commonly used for food fermentations and probiotic purposes. Due to its robust properties, it is also increasingly considered for use as a cell factory. It produces several industrially important compounds such as 1,3-propanediol and reuterin natively, but for cell factory purposes, developing improved strategies for engineering and fermentation optimization is crucial. Genome-scale metabolic models can be highly beneficial in guiding rational metabolic engineering. Reconstructing a reliable and a quantitatively accurate metabolic model requires extensive manual curation and incorporation of experimental data. Results A genome-scale metabolic model of L. reuteri JCM 1112T was reconstructed and the resulting model, Lreuteri_530, was validated and tested with experimental data. Several knowledge gaps in the metabolism were identified and resolved during this process, including presence/absence of glycolytic genes. Flux distribution between the two glycolytic pathways, the phosphoketolase and Embden–Meyerhof–Parnas pathways, varies considerably between LAB species and strains. As these pathways result in different energy yields, it is important to include strain-specific utilization of these pathways in the model. We determined experimentally that the Embden–Meyerhof–Parnas pathway carried at most 7% of the total glycolytic flux. Predicted growth rates from Lreuteri_530 were in good agreement with experimentally determined values. To further validate the prediction accuracy of Lreuteri_530, the predicted effects of glycerol addition and adhE gene knock-out, which results in impaired ethanol production, were compared to in vivo data. Examination of both growth rates and uptake- and secretion rates of the main metabolites in central metabolism demonstrated that the model was able to accurately predict the experimentally observed effects. Lastly, the potential of L. reuteri as a cell factory was investigated, resulting in a number of general metabolic engineering strategies. Conclusion We have constructed a manually curated genome-scale metabolic model of L. reuteri JCM 1112T that has been experimentally parameterized and validated and can accurately predict metabolic behavior of this important platform cell factory.
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Affiliation(s)
- Thordis Kristjansdottir
- Center for Systems Biology, School of Engineering and Natural Sciences, University of Iceland, Dunhagi 5, 107, Reykjavik, Iceland.,Matis, Vinlandsleid 12, 113, Reykjavik, Iceland
| | - Elleke F Bosma
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, 2800 Kgs., Lyngby, Denmark.,Discovery, R&D, Chr. Hansen A/S, Bøge Allé 10-12, 2970, Hørsholm, Denmark
| | - Filipe Branco Dos Santos
- Molecular Microbial Physiology Group of the Swammerdam Institute for Life Sciences, University of Amsterdam, Science Park 904, 1098 XH, Amsterdam, The Netherlands
| | - Emre Özdemir
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, 2800 Kgs., Lyngby, Denmark
| | - Markus J Herrgård
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, 2800 Kgs., Lyngby, Denmark
| | - Lucas França
- Biotrend SA - Biocant Park, Núcleo 04, Lote 2, 3060-197, Cantanhede, Portugal
| | - Bruno Ferreira
- Biotrend SA - Biocant Park, Núcleo 04, Lote 2, 3060-197, Cantanhede, Portugal
| | - Alex T Nielsen
- The Novo Nordisk Foundation Center for Biosustainability, Technical University of Denmark, Building 220, Kemitorvet, 2800 Kgs., Lyngby, Denmark
| | - Steinn Gudmundsson
- Center for Systems Biology, School of Engineering and Natural Sciences, University of Iceland, Dunhagi 5, 107, Reykjavik, Iceland.
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14
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Wang H, Mei L, Deng Y, Liu Y, Wei X, Liu M, Zhou J, Ma H, Zheng P, Yuan J, Li M. Lactobacillus brevis DM9218 ameliorates fructose-induced hyperuricemia through inosine degradation and manipulation of intestinal dysbiosis. Nutrition 2018; 62:63-73. [PMID: 30852460 DOI: 10.1016/j.nut.2018.11.018] [Citation(s) in RCA: 69] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2018] [Revised: 10/02/2018] [Accepted: 11/17/2018] [Indexed: 02/07/2023]
Abstract
OBJECTIVE High fructose consumption exacerbates purine degradation and intestinal dysbiosis, which are closely related to the development of hyperuricemia. Probiotics are powerful weapons to combat metabolic disturbance and intestinal dysbiosis. Previously we isolated a Lactobacillus strain named DM9218 that could reduce the serum uric acid (UA) level by assimilating purine nucleosides. The present study aimed to evaluate the effects of DM9218 on high-fructose-induced hyperuricemia and to elucidate the underlying mechanisms. METHODS Mice were fed a normal diet, a high-fructose diet, or high-fructose diet with DM9218. Metabolic parameters, fructose- and UA-related metabolites, and fecal microbiota were investigated. Whole-genome sequencing of strain DM9218 was also conducted. In addition, an inosine hydrolase from DM9218 was heterologously expressed in Escherichia coli, and its inosine-degrading activity was detected. RESULTS Our results indicated that DM9218 could decrease serum UA level and hepatic xanthine oxidase activity in fructose-fed mice. It could protect against high-fructose-induced liver damage and retard UA accumulation by degrading inosine. The modulation effect of DM9218 on high-fructose-induced intestinal dysbiosis resulted in enhancement of intestinal barrier function and reduction of liver lipopolysaccharide, which was closely correlated with the down-regulation of inflammatory cytokine-stimulated xanthine oxidase expression and activity. CONCLUSIONS Lactobacillus brevis DM9218 is a probiotic strain with the potential to ameliorate fructose-induced hyperuricemia.
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Affiliation(s)
- Haina Wang
- Department of Hematology, Liaoning Key Laboratory of Hematopoietic Stem Cell Transplantation and Translational Medicine, Second Hospital of Dalian Medical University, Dalian, China; Center for molecular medicine, School of Life Science and Biotechnology, Dalian University of Technology, Dalian, China
| | - Lu Mei
- Department of Gastroenterology, the Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Ying Deng
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Yinhui Liu
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Xiaoqing Wei
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Man Liu
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Jiaorui Zhou
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Hong Ma
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Pengyuan Zheng
- Department of Gastroenterology, the Fifth Affiliated Hospital of Zhengzhou University, Zhengzhou, China
| | - Jieli Yuan
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China
| | - Ming Li
- College of Basic Medical Sciences, Dalian Medical University, Dalian, China.
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15
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Maeno S, Kajikawa A, Dicks L, Endo A. Introduction of bifunctional alcohol/acetaldehyde dehydrogenase gene (adhE) in Fructobacillus fructosus settled its fructophilic characteristics. Res Microbiol 2018; 170:35-42. [PMID: 30291951 DOI: 10.1016/j.resmic.2018.09.004] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2018] [Revised: 09/13/2018] [Accepted: 09/21/2018] [Indexed: 10/28/2022]
Abstract
Fructophilic lactic acid bacteria (FLAB) are unique in the sense that they prefer D-fructose over D-glucose as main carbon source. If D-glucose is metabolised, electron acceptors are required and significant levels of acetate are produced. These bacteria are found in environments rich in D-fructose, such as flowers, fruits and the gastrointestinal tract of insects feeding on fructose-rich diets. Fructobacillus spp. are representatives of this unique group, and their fructophilic characteristics are well conserved. In this study, the bifunctional alcohol/acetaldehyde dehydrogenase gene (adhE) from Leuconostoc mesenteroides NRIC 1541T was cloned into a plasmid and transferred to Fructobacillus fructosus NRIC 1058T. Differences in biochemical characteristics between the parental strain (NRIC 1058T) and the transformants were compared. Strain 1-11, transformed with the adhE gene, did not show any fructophilic characteristics, and the strain grew well on D-glucose without external electron acceptors. Accumulation of acetic acid, which was originally seen in the parental strain, was replaced with ethanol in the transformed strain. Furthermore, in silico analyses revealed that strain NRIC 1058T lacked the sugar transporters/permeases and enzymes required for conversion of metabolic intermediates. This may be the reason for poor carbohydrate metabolic properties recorded for FLAB.
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Affiliation(s)
- Shintaro Maeno
- Department of Food, Aroma and Cosmetic Chemistry, Tokyo University of Agriculture, 099-2493, Hokkaido, Japan.
| | - Akinobu Kajikawa
- Department of Agricultural Chemistry, Tokyo University of Agriculture, 156-0083, Tokyo, Japan.
| | - Leon Dicks
- Department of Microbiology, University of Stellenbosch, Private Bag X1, 7602, Matieland, South Africa.
| | - Akihito Endo
- Department of Food, Aroma and Cosmetic Chemistry, Tokyo University of Agriculture, 099-2493, Hokkaido, Japan.
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Metabolic engineering of a glycerol-oxidative pathway in Lactobacillus panis PM1 for utilization of bioethanol thin stillage: potential to produce platform chemicals from glycerol. Appl Environ Microbiol 2014; 80:7631-9. [PMID: 25281374 DOI: 10.1128/aem.01454-14] [Citation(s) in RCA: 15] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Lactobacillus panis PM1 has the ability to produce 1,3-propanediol (1,3-PDO) from thin stillage (TS), which is the major waste material after bioethanol production, and is therefore of significance. However, the fact that L. panis PM1 cannot use glycerol as a sole carbon source presents a considerable problem in terms of utilization of this strain in a wide range of industrial applications. Accordingly, L. panis PM1 was genetically engineered to directly utilize TS as a fermentable substrate for the production of valuable platform chemicals without the need for exogenous nutrient supplementation (e.g., sugars and nitrogen sources). An artificial glycerol-oxidative pathway, comprised of glycerol facilitator, glycerol kinase, glycerol 3-phosphate dehydrogenase, triosephosphate isomerase, and NADPH-dependent aldehyde reductase genes of Escherichia coli, was introduced into L. panis PM1 in order to directly utilize glycerol for the production of energy for growth and value-added chemicals. A pH 6.5 culture converted glycerol to mainly lactic acid (85.43 mM), whereas a significant amount of 1,3-propanediol (59.96 mM) was formed at pH 7.5. Regardless of the pH, ethanol (82.16 to 83.22 mM) was produced from TS fermentations, confirming that the artificial pathway metabolized glycerol for energy production and converted it into lactic acid or 1,3-PDO and ethanol in a pH-dependent manner. This study demonstrates the cost-effective conversion of TS to value-added chemicals by the engineered PM1 strain cultured under industrial conditions. Thus, application of this strain or these research findings can contribute to reduced costs of bioethanol production.
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