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Wang X, Li Y, Liu S, Wang H, Chang X, Zhang J. Chestnut Shell Polyphenols Inhibit the Growth of Three Food-Spoilage Bacteria by Regulating Key Enzymes of Metabolism. Foods 2023; 12:3312. [PMID: 37685244 PMCID: PMC10486611 DOI: 10.3390/foods12173312] [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: 07/23/2023] [Revised: 08/24/2023] [Accepted: 08/31/2023] [Indexed: 09/10/2023] Open
Abstract
The microbial contamination of food poses a threat to human health. Chestnut shells, which are byproducts of chestnut processing, contain polyphenols that exert various physiological effects, and thus have the potential to be used in food preservation. This study investigates the bacteriostatic effect and mechanism(s) of the action of chestnut shell polyphenols (CSPs) on three food-spoilage bacteria, namely Bacillus subtilis, Pseudomonas fragi, and Escherichia coli. To this end, the effect of CSPs on the ultrastructure of each bacterium was determined using scanning electron microscopy and transmission electron microscopy. Moreover, gene expression was analyzed using RT-qPCR. Subsequent molecular docking analysis was employed to elucidate the mechanism of action employed by CSPs via the inhibition of key enzymes. Ultrastructure analysis showed that CSPs damaged the bacterial cell wall and increased permeability. At 0.313 mg/mL, CSPs significantly increased the activity of alkaline phosphatase and lactate dehydrogenase, as well as protein leakage (p < 0.05), whereas the activity of the tricarboxylic acid (TCA) cycle enzymes, isocitrate dehydrogenase and α-ketoglutarate dehydrogenase, were inhibited (p < 0.05). The expression levels of the TCA-related genes gltA, icd, sucA, atpA, citA, odhA, IS178_RS16090, and IS178_RS16290 are also significantly downregulated by CSP treatment (p < 0.05). Moreover, CSPs inhibit respiration and energy metabolism, including ATPase activity and adenosine triphosphate (ATP) synthesis (p < 0.05). Molecular docking determined that proanthocyanidins B1 and C1, the main components of CSPs, are responsible for the antibacterial activity. Therefore, as natural antibacterial substances, CSPs have considerable potential for development and application as natural food preservatives.
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Affiliation(s)
- Xinfang Wang
- College of Food Science & Technology, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China
| | - Yue Li
- College of Food Science & Technology, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China
| | - Suwen Liu
- College of Food Science & Technology, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China
- Engineering Research Center of Chestnut Industry Technology of Ministry of Education, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China
| | - Hao Wang
- State Key Laboratory of Food Nutrition and Safety, Tianjin University of Science and Technology (TUST), Tianjin 300457, China
| | - Xuedong Chang
- Engineering Research Center of Chestnut Industry Technology of Ministry of Education, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China
| | - Jingzheng Zhang
- Engineering Research Center of Chestnut Industry Technology of Ministry of Education, Hebei Normal University of Science and Technology, Qinhuangdao 066004, China
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Leng W, Wu X, Xiong Z, Shi T, Sun Q, Yuan L, Gao R. Study on antibacterial properties of mucus extract of snakehead (Channa argus) against Escherichia coli and its application in chilled fish fillets preservation. Lebensm Wiss Technol 2022. [DOI: 10.1016/j.lwt.2022.113840] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022]
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3
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Energy metabolism as the target of 3-phenyllactic acid against Rhizopus oryzae. Int J Food Microbiol 2022; 369:109606. [DOI: 10.1016/j.ijfoodmicro.2022.109606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2021] [Revised: 02/19/2022] [Accepted: 02/26/2022] [Indexed: 11/20/2022]
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Chen X, Dong X, Liu J, Luo Q, Liu L. Pathway engineering of Escherichia coli for α-ketoglutaric acid production. Biotechnol Bioeng 2020; 117:2791-2801. [PMID: 32530489 DOI: 10.1002/bit.27456] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/29/2020] [Revised: 05/19/2020] [Accepted: 06/11/2020] [Indexed: 01/09/2023]
Abstract
α-Ketoglutaric acid (α-KG) is a multifunctional dicarboxylic acid in the tricarboxylic acid (TCA) cycle, but microbial engineering for α-KG production is not economically efficient, due to the intrinsic inefficiency of its biosynthetic pathway. In this study, pathway engineering was used to improve pathway efficiency for α-KG production in Escherichia coli. First, the TCA cycle was rewired for α-KG production starting from pyruvate, and the engineered strain E. coli W3110Δ4-PCAI produced 15.66 g/L α-KG. Then, the rewired TCA cycle was optimized by designing various strengths of pyruvate carboxylase and isocitrate dehydrogenase expression cassettes, resulting in a large increase in α-KG production (24.66 g/L). Furthermore, acetyl coenzyme A (acetyl-CoA) availability was improved by overexpressing acetyl-CoA synthetase, leading to α-KG production up to 28.54 g/L. Finally, the engineered strain E. coli W3110Δ4-P(H) CAI(H) A was able to produce 32.20 g/L α-KG in a 5-L fed-batch bioreactor. This strategy described here paves the way to the development of an efficient pathway for microbial production of α-KG.
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Affiliation(s)
- Xiulai Chen
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Xiaoxiang Dong
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Jia Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
| | - Qiuling Luo
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.,Wuxi Chenming Biotechnology Co., Ltd., Wuxi, China
| | - Liming Liu
- State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, China.,Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, Wuxi, China.,International Joint Laboratory on Food Safety, Jiangnan University, Wuxi, China
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Chen J, Tang C, Zhang R, Ye S, Zhao Z, Huang Y, Xu X, Lan W, Yang D. Metabolomics analysis to evaluate the antibacterial activity of the essential oil from the leaves of Cinnamomum camphora (Linn.) Presl. JOURNAL OF ETHNOPHARMACOLOGY 2020; 253:112652. [PMID: 32035880 DOI: 10.1016/j.jep.2020.112652] [Citation(s) in RCA: 60] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/18/2019] [Revised: 01/11/2020] [Accepted: 02/03/2020] [Indexed: 06/10/2023]
Abstract
ETHNOPHARMACOLOGY RELEVANCE Cinnamomum camphora (Linn.) Presl (C. camphora) is one of the oldest herbal medicines used as a traditional medicine, owning a wide range of biological functions including anti-bacterial, anti-oxidative, anti-fungal, anti-inflammatory, insecticidal and repellent activities. OBJECTIVE The aim of this study was to investigate the antibacterial activity and mechanism of action of the essential oil (EO) from C. camphora. MATERIALS AND METHODS The EO was isolated from the leaves of C. camphora by hydrodistillation, and the chemical compositions of the EO were analyzed by gas chromatography-mass spectrometry (GC-MS). The minimum inhibitory concentration (MIC) and the minimal bactericidal concentration (MBC) values of the EO were estimated by the microbroth dilution method. Growth curve was investigated by turbidimetry. Apoptosis was measured by flow cytometry. Morphological change of bacteria was observed by field emission scanning electron microscopy and transmission electron microscopy. The integrity of cell membrane was evaluated by NanoDrop and BCA Protein Assay Kit. The methicillin-resistant Staphylococcus aureus (MRSA) metabolic profile in the presence of the EO was explored by GC-MS-based metabolomics. Isocitrate dehydrogenase (ICDH), α-ketoglutarate dehydrogenase (α-KGDH), succinic dehydrogenase (SDH) and malic dehydrogenase (MDH) activities were detected by commercial kits. RESULTS The main components of the EO from the leaves of C. camphora were identified to be linalool (26.6%), eucalyptol (16.8%), α-terpineol (8.7%), isoborneol (8.1%), β-phellandrene (5.1%), and camphor (5.0%). The EO had good activity against MRSA, Staphylococcus aureus, Enterococcus faecalis, Bacillus subtilis, Salmonella gallinarum and Escherichia coli. MRSA was selected as the model bacterium to illustrate antibacterial mechanism of action of the EO, and the MIC and MBC values was 0.8 and 1.6 mg/mL, respectively. Apoptosis rate of MRSA increased in a concentration-dependent manner after the addition of EO. The cell morphology was damaged by the EO. There were 74 significantly different metabolites, including 29 upregulated and 45 downregulated metabolites in the result of metabolomics evaluation. Seven pathways were enriched by shared differential metabolites. The EO enhanced the activity of ICDH by 47.35%, while weaken MDH, SDH and α-KGDH by 72.63%, 31.52% and 63.29%, respectively. CONCLUSIONS The EO from C. camphora showed anti-MRSA activity via damaging cell membranes and disturbing the amino metabolism.
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Affiliation(s)
- Jiali Chen
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong Province, China
| | - Cailin Tang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong Province, China
| | - Rongfei Zhang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong Province, China
| | - Shaoxia Ye
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong Province, China
| | - Zhimin Zhao
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong Province, China
| | - Yuquan Huang
- China Resources Sanjiu Medical & Pharmaceutical Co.,Ltd., Shenzhen, 518110, Guangdong Province, China
| | - Xinjun Xu
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong Province, China
| | - Wenjian Lan
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong Province, China
| | - Depo Yang
- School of Pharmaceutical Sciences, Sun Yat-Sen University, Guangzhou, 510006, Guangdong Province, China.
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The mitochondrial citrate carrier in Yarrowia lipolytica: Its identification, characterization and functional significance for the production of citric acid. Metab Eng 2019; 54:264-274. [PMID: 31071446 DOI: 10.1016/j.ymben.2019.05.002] [Citation(s) in RCA: 40] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/09/2019] [Revised: 04/30/2019] [Accepted: 05/03/2019] [Indexed: 12/21/2022]
Abstract
Mitochondrial citrate carrier plays a central role in exporting acetyl-CoA in the form of citrate from mitochondria to cytosol thereby connecting carbohydrate catabolism and lipogenesis. In this study, Yarrowia lipolytica mitochondrial citrate carrier was functionally defined and characterized. Firstly, deletion of Y. lipolytica YlCTP1 and YlYHM2 genes coding putative tricarboxylate mitochondrial carriers were performed. ΔYlctp1 strain did not differ significantly from wild type strain in terms of growth rate, organic acids and lipid production. In contrast, ΔYlyhm2 strain did not grow in liquid citrate-containing minimal medium. Moreover, in glucose-containing lipogenic medium YlYHM2 null mutant strain did not produce citric acid; the production of isocitric acid and lipids were decreased. Reintroduction of YlYHM2 gene as well as heterologous expression of Aspergillus niger gene AnYHM2 into ΔYlyhm2 strain restored the growth in minimal citrate medium and even enhanced citric acid production by 45% in both variants compared with wild type strain during test tube cultivation. Mitochondrial extracts isolated from YlYHM2 null mutant and wild type strain were incorporated into liposomes; citrate/citrate and α-ketoglutarate/α-ketoglutarate homoexchange activities were reduced by 87% and 40% in ΔYlyhm2 strain, respectively, compared with the wild type, whereas citratein/α-ketoglutarateout and α-ketoglutaratein/citrateout heteroexchanges were decreased by 87% and 95%, respectively. YlYhm2p was expressed in Escherichia coli, purified and reconstituted into liposomes. Besides high efficiency to citrate and α-ketoglutarate transport, YlYhm2p also transported oxaloacetate, succinate, fumarate, and to a much lesser extent, aconitate, malate, isocitrate, oxoadipate, and glutamate. The activity of reconstituted YlYhm2p was inhibited strongly by SH-blocking reagents, pyridoxal-5'-phosphate, and partly by N-ethylmaleimide. Co-expression of YlYHM2 and adenosine monophosphate deaminase YlAMPD genes resulted in the production of 49.7 g/L of citric acid during test tube cultivation, whereas wild type strain accumulated 30.1 g/L of citric acid. Large-scale cultivation in bioreactor of the engineered strain resulted in 97.1 g/L of citric acid production with a process selectivity of 94.2% and an overall citric acid yield of 0.5 g/g. The maximal specific rate of citric acid synthesis was 0.93 g/L/h. Therefore, the physiological role of YlYhm2p in glucose-containing medium is to catalyze both import of citrate into mitochondria for catabolic reactions and export of citrate as a source of acetyl-CoA from mitochondria. Possible shuttles for citrate exporting are discussed. Moreover, for the first time evidence has been given for the improvement of TCA cycle intermediate production by manipulation of a gene coding a mitochondrial carrier.
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Shi S, Zhao H. Metabolic Engineering of Oleaginous Yeasts for Production of Fuels and Chemicals. Front Microbiol 2017; 8:2185. [PMID: 29167664 PMCID: PMC5682390 DOI: 10.3389/fmicb.2017.02185] [Citation(s) in RCA: 62] [Impact Index Per Article: 8.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/13/2017] [Accepted: 10/25/2017] [Indexed: 01/23/2023] Open
Abstract
Oleaginous yeasts have been increasingly explored for production of chemicals and fuels via metabolic engineering. Particularly, there is a growing interest in using oleaginous yeasts for the synthesis of lipid-related products due to their high lipogenesis capability, robustness, and ability to utilize a variety of substrates. Most of the metabolic engineering studies in oleaginous yeasts focused on Yarrowia that already has plenty of genetic engineering tools. However, recent advances in systems biology and synthetic biology have provided new strategies and tools to engineer those oleaginous yeasts that have naturally high lipid accumulation but lack genetic tools, such as Rhodosporidium, Trichosporon, and Lipomyces. This review highlights recent accomplishments in metabolic engineering of oleaginous yeasts and recent advances in the development of genetic engineering tools in oleaginous yeasts within the last 3 years.
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Affiliation(s)
- Shuobo Shi
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, China
- Metabolic Engineering Research Laboratory, Science and Engineering Institutes, Agency for Science, Technology and Research, Singapore, Singapore
| | - Huimin Zhao
- Beijing Advanced Innovation Center for Soft Matter Science and Engineering, Beijing University of Chemical Technology, Beijing, China
- Metabolic Engineering Research Laboratory, Science and Engineering Institutes, Agency for Science, Technology and Research, Singapore, Singapore
- Department of Chemical and Biomolecular Engineering, University of Illinois at Urbana-Champaign, Urbana, IL, United States
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Xu J, Shao X, Li Y, Wei Y, Xu F, Wang H. Metabolomic Analysis and Mode of Action of Metabolites of Tea Tree Oil Involved in the Suppression of Botrytis cinerea. Front Microbiol 2017; 8:1017. [PMID: 28634477 PMCID: PMC5459894 DOI: 10.3389/fmicb.2017.01017] [Citation(s) in RCA: 35] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2017] [Accepted: 05/22/2017] [Indexed: 12/25/2022] Open
Abstract
Tea tree oil (TTO), a volatile essential oil, has been widely used as an antimicrobial agent. However, the mechanism underlying TTO antifungal activity is not fully understood. In this study, a comprehensive metabolomics survey was undertaken to identify changes in metabolite production in Botrytis cinerea cells treated with TTO. Significant differences in 91 metabolites were observed, including 8 upregulated and 83 downregulated metabolites in TTO-treated cells. The results indicate that TTO inhibits primary metabolic pathways through the suppression of the tricarboxylic acid (TCA) cycle and fatty acid metabolism. Further experiments show that TTO treatment decreases the activities of key enzymes in the TCA cycle and increases the level of hydrogen peroxide (H2O2). Membrane damage is also induced by TTO treatment. We hypothesize that the effect of TTO on B. cinerea is achieved mainly by disruption of the TCA cycle and fatty acid metabolism, resulting in mitochondrial dysfunction and oxidative stress.
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Affiliation(s)
| | - Xingfeng Shao
- Department of Food Science and Engineering, Ningbo UniversityNingbo, China
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Applying pathway engineering to enhance production of alpha-ketoglutarate in Yarrowia lipolytica. Appl Microbiol Biotechnol 2016; 100:9875-9884. [DOI: 10.1007/s00253-016-7913-x] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/17/2016] [Revised: 09/27/2016] [Accepted: 09/29/2016] [Indexed: 12/29/2022]
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10
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Zeng W, Fang F, Liu S, Du G, Chen J, Zhou J. Comparative genomics analysis of a series of Yarrowia lipolytica WSH-Z06 mutants with varied capacity for α-ketoglutarate production. J Biotechnol 2016; 239:76-82. [PMID: 27732868 DOI: 10.1016/j.jbiotec.2016.10.008] [Citation(s) in RCA: 13] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/25/2016] [Revised: 09/16/2016] [Accepted: 10/07/2016] [Indexed: 01/23/2023]
Abstract
Yarrowia lipolytica is one of the most intensively investigated α-ketoglutaric acid (α-KG) producers, and metabolic engineering has proven effective for enhancing production. However, regulation of α-KG metabolism remains poorly understood. Genetic engineering of new strains is accompanied by potential safety concerns in some countries and regions. A series of mutants with varied capacity for α-KG production were obtained using random mutagenesis of Y. lipolytica WSH-Z06. Comparative genomics analysis was implemented to identify genes candidates associated with α-KG production. Manipulation of genes regulating mitochondrial biogenesis and energy metabolism could improve α-KG production, while genes involved in regulating transformation between keto acids and amino acids may decrease production. One gene associated with cell cycle control well represented in all mutants, whereas this gene involved in cell concentration do not appear to influence α-KG production. The results shed light on α-KG production in eukaryotic cells, and pave the way for a high-throughput screening and random mutagenesis method for enhancing α-KG production.
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Affiliation(s)
- Weizhu Zeng
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Fang Fang
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Song Liu
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Guocheng Du
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Jian Chen
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, 1800 Lihu Road, Wuxi, Jiangsu 214122, China
| | - Jingwen Zhou
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu 214122, China; Synergetic Innovation Center of Food Safety and Nutrition, 1800 Lihu Road, Wuxi, Jiangsu 214122, China.
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Guo H, Wan H, Chen H, Fang F, Liu S, Zhou J. Proteomic analysis of the response of α-ketoglutarate-producer Yarrowia lipolytica WSH-Z06 to environmental pH stimuli. Appl Microbiol Biotechnol 2016; 100:8829-41. [PMID: 27535241 DOI: 10.1007/s00253-016-7775-2] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2016] [Revised: 07/25/2016] [Accepted: 08/02/2016] [Indexed: 11/25/2022]
Abstract
During bioproduction of short-chain carboxylates, a shift in pH is a common strategy for enhancing the biosynthesis of target products. Based on two-dimensional gel electrophoresis, comparative proteomics analysis of general and mitochondrial protein samples was used to investigate the cellular responses to environmental pH stimuli in the α-ketoglutarate overproducer Yarrowia lipolytica WSH-Z06. The lower environmental pH stimuli tensioned intracellular acidification and increased the level of reactive oxygen species (ROS). A total of 54 differentially expressed protein spots were detected, and 11 main cellular processes were identified to be involved in the cellular response to environmental pH stimuli. Slight decrease in cytoplasmic pH enhanced the cellular acidogenicity by elevating expression level of key enzymes in tricarboxylic acid cycle (TCA cycle). Enhanced energy biosynthesis, ROS elimination, and membrane potential homeostasis processes were also employed as cellular defense strategies to compete with environmental pH stimuli. Owing to its antioxidant role of α-ketoglutarate, metabolic flux shifted to α-ketoglutarate under lower pH by Y. lipolytica in response to acidic pH stimuli. The identified differentially expressed proteins provide clues for understanding the mechanisms of the cellular responses and for enhancing short-chain carboxylate production through metabolic engineering or process optimization strategies in combination with manipulation of environmental conditions.
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Affiliation(s)
- Hongwei Guo
- Department of Biotechnology and Bioengineering, School of Chemical Engineering and Key Laboratory of Fujian Province for Biological Chemical Engineering, Huaqiao University, 668 Jimei Road, Amoy, Fujian, 361021, China.,School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China
| | - Hui Wan
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China
| | - Hongwen Chen
- Department of Biotechnology and Bioengineering, School of Chemical Engineering and Key Laboratory of Fujian Province for Biological Chemical Engineering, Huaqiao University, 668 Jimei Road, Amoy, Fujian, 361021, China
| | - Fang Fang
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China
| | - Song Liu
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China
| | - Jingwen Zhou
- School of Biotechnology and Key Laboratory of Industrial Biotechnology, Ministry of Education, Jiangnan University, 1800 Lihu Road, Wuxi, Jiangsu, 214122, China.
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