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Firdose A, Maeda T, Sukri MAM, Yasin NHM, Sabturani N, Aqma WS. Antibacterial mechanism of Pseudomonas aeruginosa UKMP14T rhamnolipids against multidrug resistant Acinetobacter baumannii. Microb Pathog 2024; 193:106743. [PMID: 38879138 DOI: 10.1016/j.micpath.2024.106743] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2023] [Revised: 06/06/2024] [Accepted: 06/11/2024] [Indexed: 06/21/2024]
Abstract
Rhamnolipids, a major category of glycolipid biosurfactant, have recently gained enormous attention in medical field because of their relevance as effective antibacterial agents against a wide variety of pathogenic bacteria. Our previous studies have shown that rhamnolipids from an environmental isolate of Pseudomonas aeruginosa UKMP14T possess antibacterial, anti-adhesive and anti-biofilm activity against multidrug-resistant ESKAPE (Enterococcus faecium, Staphylococcus aureus, Klebsiella pneumoniae, Acinetobacter baumannii, Pseudomonas aeruginosa and Enterobacter sp.) pathogens. However, the mechanism of their antibacterial action remains unclear. Thus, this study aimed to elucidate the mechanism of the antibacterial action of P. aeruginosa UKMP14T rhamnolipids by studying the changes in cells of one of the ESKAPE pathogens, Acinetobacter baumannii, which is the most difficult strain to kill. Results revealed that rhamnolipid treatment rendered A. baumannii cells more hydrophobic as evaluated through contact angle measurements. It also induced the release of cellular proteins measuring 510 μg/mL at a rhamnolipid concentration of 1000 μg/mL. In addition, rhamnolipids were found to be bactericidal in their action as they could permeate the inner membranes, leading to a leak-out of nucleotides. More than 50 % of the cells were found to be killed upon 1000 μg/mL rhamnolipid treatment as observed through fluorescence microscopy. Other cellular changes such as irregular shape and size, membrane perturbations, clumping, shrinkage and physical damage were clearly visible in SEM, FESEM and laser micrographs. Furthermore, rhamnolipid treatment inhibited the levels of acyl-homoserine lactones (AHLs) in A. baumannii, which are vital for their biofilm formation and virulence. The obtained results indicate that P. aeruginosa UKMP14T rhamnolipids target outer and inner bacterial membranes through permeation, including physical damage to the cells, leading to cell leakage. Furthermore, AHL inhibition appears to be the mechanism behind their anti-biofilm action. All these observations can be correlated to rhamnolipids' antibacterial effect against A. baumannii.
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Affiliation(s)
- Ayesha Firdose
- Department of Biological Sciences & Biotechnology, Faculty of Science & Technology, Universiti Kebangsaan Malaysia, 46300 Bangi, Selangor, Malaysia.
| | - Toshinari Maeda
- Department of Biological Functions Engineering, Graduate School of Life Science and Systems Engineering, Kyushu Institute of Technology, 2-4 Hibikino, Wakamatsu-ku, Kitakyushu 808-0196, Japan
| | - Mohd Asif Mohd Sukri
- Department of Biological Sciences & Biotechnology, Faculty of Science & Technology, Universiti Kebangsaan Malaysia, 46300 Bangi, Selangor, Malaysia
| | - Nazlina Haiza Mohd Yasin
- Department of Biological Sciences & Biotechnology, Faculty of Science & Technology, Universiti Kebangsaan Malaysia, 46300 Bangi, Selangor, Malaysia
| | - Noramiza Sabturani
- Department of Biological Sciences & Biotechnology, Faculty of Science & Technology, Universiti Kebangsaan Malaysia, 46300 Bangi, Selangor, Malaysia
| | - Wan Syaidatul Aqma
- Department of Biological Sciences & Biotechnology, Faculty of Science & Technology, Universiti Kebangsaan Malaysia, 46300 Bangi, Selangor, Malaysia.
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Lin YT, Wang YC, Xue YM, Tong Z, Jiang GY, Hu XR, Crittenden JC, Wang C. Decoding the influence of low temperature on biofilm development: The hidden roles of c-di-GMP. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 927:172376. [PMID: 38604376 DOI: 10.1016/j.scitotenv.2024.172376] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/28/2023] [Revised: 04/06/2024] [Accepted: 04/08/2024] [Indexed: 04/13/2024]
Abstract
Biofilms are widely used and play important roles in biological processes. Low temperature of wastewater inhibits the development of biofilms derived from wastewater activated sludge. However, the specific mechanism of temperature on biofilm development is still unclear. This study explored the mechanism of temperature on biofilm development and found a feasible method to enhance biofilm development at low temperature. The amount of biofilm development decreased by approximately 66 % and 55 % at 4 °C and 15 °C, respectively, as compared to 28 °C. The cyclic dimeric guanosine monophosphate (c-di-GMP) concentration also decreased at low temperature and was positively correlated with extracellular polymeric substance (EPS) content, formation, and adhesion strength. Microbial community results showed that low temperature inhibited the normal survival of most microorganisms, but promoted the growth of some psychrophile bacteria like Sporosarcina, Caldilineaceae, Gemmataceae, Anaerolineaceae and Acidobacteriota. Further analysis of functional genes demonstrated that the abundance of functional genes related to the synthesis of c-di-GMP (K18968, K18967 and K13590) decreased at low temperature. Subsequently, the addition of exogenous spermidine increased the level of intracellular c-di-GMP and alleviated the inhibition effect of low temperature on biofilm development. Therefore, the possible mechanism of low temperature on biofilm development could be the inhibition of the microorganism activity and reduction of the communication level between cells, which is the closely related to the EPS content, formation, and adhesion strength. The enhancement of c-di-GMP level through the exogenous addition of spermidine provides an alternative strategy to enhance biofilm development at low temperatures. The results of this study enhance the understanding of the influence of temperature on biofilm development and provide possible strategies for enhancing biofilm development at low temperatures.
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Affiliation(s)
- Yu-Ting Lin
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - Yong-Chao Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China.
| | - Yi-Mei Xue
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - Zhen Tong
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - Guan-Yu Jiang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - Xu-Rui Hu
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China
| | - John C Crittenden
- School of Civil and Environmental Engineering, Georgia Institute of Technology, Atlanta, GA 30332, United States
| | - Can Wang
- School of Environmental Science and Engineering, Tianjin University, Tianjin 300072, China; Tianjin Key Lab of Indoor Air Environmental Quality Control, Tianjin 300072, China.
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Bi J, Yao Q, Zhang G, Hou H. The Phase-Dependent Regulation of Lux-Type Genes on the Spoilage Characteristics of Hafnia alvei. Foods 2024; 13:688. [PMID: 38472800 DOI: 10.3390/foods13050688] [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: 02/08/2024] [Revised: 02/20/2024] [Accepted: 02/23/2024] [Indexed: 03/14/2024] Open
Abstract
Hafnia alvei, a specific spoilage microorganism, has a strong capacity to destroy food protein and lead to spoilage. The aim of this study was to evaluate the phase-dependent regulation of lux-type genes on the spoilage characteristics of H. alvei H4. The auto-inducer synthase gene luxI and a regulatory gene luxR of the quorum sensing systems in H. alvei H4 were knocked out to construct the mutant phenotypes. On this basis, the research found that the luxI and luxR genes had a strong positive influence on not only flagella-dependent swimming ability and biofilm formation but also the production of putrescine and cadaverine. The luxR gene could downregulate putrescine production. The maximum accumulation of putrescine in wild type, ΔluxI, ΔluxR and ΔluxIR were detected at 24 h, reaching up to 695.23 mg/L, 683.02 mg/L, 776.30 mg/L and 724.12 mg/L, respectively. However, the luxI and luxR genes have a potential positive impact on the production of cadaverine. The maximum concentration of cadaverine produced by wild type, ΔluxI, ΔluxR and ΔluxIR were 252.7 mg/L, 194.5 mg/L, 175.1 mg/L and 154.2 mg/L at 72 h. Moreover, the self-organizing map analysis revealed the phase-dependent effects of two genes on spoilage properties. The luxI gene played a major role in the lag phase, while the luxR gene mainly acted in the exponential and stationary phases. Therefore, the paper provides valuable insights into the spoilage mechanisms of H. alvei H4.
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Affiliation(s)
- Jingran Bi
- School of Food Science and Technology, Dalian Polytechnic University, No. 1, Qinggongyuan, Ganjingzi District, Dalian 116034, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1, Qinggongyuan, Ganjingzi District, Dalian 116034, China
| | - Qiaoli Yao
- School of Food Science and Technology, Dalian Polytechnic University, No. 1, Qinggongyuan, Ganjingzi District, Dalian 116034, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1, Qinggongyuan, Ganjingzi District, Dalian 116034, China
| | - Gongliang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, No. 1, Qinggongyuan, Ganjingzi District, Dalian 116034, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1, Qinggongyuan, Ganjingzi District, Dalian 116034, China
| | - Hongman Hou
- School of Food Science and Technology, Dalian Polytechnic University, No. 1, Qinggongyuan, Ganjingzi District, Dalian 116034, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1, Qinggongyuan, Ganjingzi District, Dalian 116034, China
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Wang Y, Li X, Zhang G, Bi J, Hou H. Transcriptome Reveals Regulation of Quorum Sensing of Hafnia alvei H4 on the Coculture System of Hafnia alvei H4 and Pseudomonas fluorescens ATCC13525. Foods 2024; 13:336. [PMID: 38275703 PMCID: PMC10815324 DOI: 10.3390/foods13020336] [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: 11/27/2023] [Revised: 01/16/2024] [Accepted: 01/19/2024] [Indexed: 01/27/2024] Open
Abstract
In the food industry, foodborne spoilage bacteria often live in mixed species and attach to each other, leading to changes in spoilage characteristics. Quorum sensing (QS) has been reported to be a regulating mechanism for food spoiling by certain kinds of bacteria. Here, the contents of biofilm, extracellular polysaccharides, and biogenic amines in the coculture system of Hafnia alvei H4 and Pseudomonas fluorescens ATCC13525 were significantly reduced when the QS element of H. alvei H4 was deleted, confirming that QS of H. alvei H4 is involved in the dual-species interactions. Then, transcriptomics was used to explore the regulatory mechanism at the mRNA molecular level. The deletion of the QS element decreased the transcript levels of genes related to chemotaxis, flagellar assembly, and the two-component system pathway of H. alvei H4 in the coculture system. Furthermore, a total of 732 DEGs of P. fluorescens ATCC13525 were regulated in the dual species, which were primarily concerned with biofilm formation, ATP-binding cassette transporters, and amino acid metabolism. Taken together, the absence of the QS element of H. alvei H4 weakened the mutual cooperation of the two bacteria in the coculture system, making it a good target for managing infection with H. alvei and P. fluorescens.
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Affiliation(s)
- Yanan Wang
- School of Food Science and Technology, Dalian Polytechnic University, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China; (Y.W.); (X.L.); (G.Z.); (J.B.)
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China
| | - Xue Li
- School of Food Science and Technology, Dalian Polytechnic University, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China; (Y.W.); (X.L.); (G.Z.); (J.B.)
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China
| | - Gongliang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China; (Y.W.); (X.L.); (G.Z.); (J.B.)
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China
| | - Jingran Bi
- School of Food Science and Technology, Dalian Polytechnic University, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China; (Y.W.); (X.L.); (G.Z.); (J.B.)
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China
| | - Hongman Hou
- School of Food Science and Technology, Dalian Polytechnic University, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China; (Y.W.); (X.L.); (G.Z.); (J.B.)
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No. 1 Qinggongyuan, Ganjingzi District, Dalian 116034, China
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Cheng J, Su X, Liu M, Lu Z, Xu J, He Y. Simultaneous regulation of biocathodic γ-HCH dechlorination and CH 4 production by tailoring the structure and function of biofilms based on quorum sensing. ENVIRONMENTAL POLLUTION (BARKING, ESSEX : 1987) 2023; 335:122357. [PMID: 37567403 DOI: 10.1016/j.envpol.2023.122357] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2023] [Revised: 08/01/2023] [Accepted: 08/08/2023] [Indexed: 08/13/2023]
Abstract
Dechlorination of chlorinated organic pollutants and methanogenesis are attractive biocathode reductions in microbial electrolysis cells (MECs). Quorum sensing (QS) is applied to regulate microbial communications. However, how acyl-homoserine lactones (AHLs)-dependent QS organize the assembly of the biocathode microbial community, and then regulate multiple biocathode reductions remains unclear. By applying N-butanoyl homoserine lactone (C4-HSL), N-hexanoyl homoserine lactone (C6-HSL) and 3-oxo-hexanoyl homoserine lactone (3OC6-HSL) in γ-hexachlorocyclohexane (γ-HCH) contaminated MECs, this study investigated the changes of biofilm microbial structure and function and the mechanisms of AHLs-QS on γ-HCH dechlorination and CH4 production. Exogenous C4-HSL and 3OC6-HSL increased cytochrome c production and enriched dechlorinators, electroactive bacteria but not methanogens to accelerate γ-HCH dechlorination and inhibit CH4 production. C6-HSL facilitated dechlorination and CH4 production by enhancing biofilm electroactivity and increasing membrane transportation. Besides, exogenous C6-HSL restored the electron transfer capacity that was damaged by the concurrent addition of acylase, an endogenous AHL quencher. From the perspective of microbial assembly, this study sheds insights into and provides an efficient strategy to selectively accelerate dechlorination and CH4 production by harnessing microbial structure based on QS systems to meet various environmental demands.
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Affiliation(s)
- Jie Cheng
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Xin Su
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Meng Liu
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Zhijiang Lu
- Department of Environmental Science and Geology, Wayne State University, Detroit, MI, 48201, United States.
| | - Jianming Xu
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China.
| | - Yan He
- Zhejiang Provincial Key Laboratory of Agricultural Resources and Environment, Institute of Soil and Water Resources and Environmental Science, College of Environmental and Resource Sciences, Zhejiang University, Hangzhou, 310058, China; Key Laboratory of Environment Remediation and Ecological Health, Ministry of Education, Hangzhou, 310058, China.
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6
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Li X, Yan C, Wang Y, Zhang G, Bi J, Hao H, Hou H. Potential quorum-sensing inhibitor of Hafnia alvei H4-theaflavin-3,3´-digallate analyzed by virtual screening and molecular simulation. Microbiol Spectr 2023; 11:e0267123. [PMID: 37732782 PMCID: PMC10580929 DOI: 10.1128/spectrum.02671-23] [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: 07/08/2023] [Accepted: 07/31/2023] [Indexed: 09/22/2023] Open
Abstract
Hafnia species can cause food spoilage via the quorum-sensing (QS) system. Thus, strategies that target QS in these bacteria might be a good approach to safeguard the quality of processed food. In this study, the amino acid sequence of the LasI Ha protein, a key QS regulator from Hafnia alvei H4, was used to construct its 3D structure for the virtual screening of potential QS inhibitors (QSIs) from the Bioactive Compound database. Four potential QSIs were obtained, and these were all theaflavins (TFs). Among them, theaflavin-3,3´-digallate (TF3) was found to outperform the others, displaying a higher docking score according to molecular docking analysis, and required only a sub-minimal inhibitory concentration (31.25 mM) to cause a significant decrease in the production of the autoinducer N-acyl homoserine lactone in H. alvei H4 and up to 60.5% inhibition of its motility. Furthermore, molecular simulation results indicated that TF3 could stably bind to a cavity within LasI Ha to form stable hydrogen bonds and hydrophobic interactions with various key residues of the protein to exert the inhibitory effect. Thus, TF3 may be considered a potential compound to protect against food spoilage caused by H. alvei H4 via the quorum quenching. IMPORTANCE Hafnia alvei, the main strain studied in this paper, is often isolated from spoiled foods, especially refrigerated protein-based raw foods, and is generally considered to be a spoilage bacterium whose spoilage-causing properties may be closely related to its own very strong population-sensing activity, so the strategy of quorum quenching against H. alvei H4 may be a good way to guarantee the quality of processed foods. Given the current global requirements for food safety and quality, coupled with negative consumer perceptions of the excessive inclusion of synthetic chemicals in food products, the use of natural compounds as QSIs in the storage of aquatic food products would seem more attractive.
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Affiliation(s)
- Xue Li
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Congyang Yan
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Yanan Wang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Gongliang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Jingran Bi
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Hongshun Hao
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Hongman Hou
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
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Arias-Gaguancela O, Herrell E, Aziz M, Chapman KD. Two legume fatty acid amide hydrolase isoforms with distinct preferences for microbial- and plant-derived acylamides. Sci Rep 2023; 13:7486. [PMID: 37161076 PMCID: PMC10169808 DOI: 10.1038/s41598-023-34754-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/22/2022] [Accepted: 05/06/2023] [Indexed: 05/11/2023] Open
Abstract
Fatty acid amide hydrolase (FAAH) is a widely conserved amidase in eukaryotes, perhaps best known for inactivating N-acylethanolamine lipid mediators. However, FAAH enzymes hydrolyze a wide range of acylamide substrates. Analysis of FAAHs from multiple angiosperm species revealed two conserved phylogenetic groups that differed in key conserved residues in the substrate binding pocket. While the foundation group of plant FAAHs, designated FAAH1, has been studied at the structural and functional level in Arabidopsis thaliana, nothing is known about FAAH2 members. Here, we combined computational and biochemical approaches to compare the structural and enzymatic properties of two FAAH isoforms in the legume Medicago truncatula designated MtFAAH1 and MtFAAH2a. Differences in structural and physicochemical properties of the substrate binding pockets, predicted from homology modeling, molecular docking, and molecular dynamic simulation experiments, suggested that these two FAAH isoforms would exhibit differences in their amidohydrolase activity profiles. Indeed, kinetic studies of purified, recombinant MtFAAHs indicated a reciprocal preference for acylamide substrates with MtFAAH1 more efficiently utilizing long-chain acylamides, and MtFAAH2a more efficiently hydrolyzing short-chain and aromatic acylamides. This first report of the enzymatic behavior of two phylogenetically distinct plant FAAHs will provide a foundation for further investigations regarding FAAH isoforms in legumes and other plant species.
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Affiliation(s)
- Omar Arias-Gaguancela
- BioDiscovery Institute, Department of Biological Sciences, University of North Texas, Denton, TX, USA
| | - Emily Herrell
- BioDiscovery Institute, Department of Biological Sciences, University of North Texas, Denton, TX, USA
| | - Mina Aziz
- BioDiscovery Institute, Department of Biological Sciences, University of North Texas, Denton, TX, USA
| | - Kent D Chapman
- BioDiscovery Institute, Department of Biological Sciences, University of North Texas, Denton, TX, USA.
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Wang D, Cui F, Ren L, Li J, Li T. Quorum-quenching enzymes: Promising bioresources and their opportunities and challenges as alternative bacteriostatic agents in food industry. Compr Rev Food Sci Food Saf 2023; 22:1104-1127. [PMID: 36636773 DOI: 10.1111/1541-4337.13104] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/21/2022] [Revised: 12/18/2022] [Accepted: 12/21/2022] [Indexed: 01/14/2023]
Abstract
The problems of spoilage, disease, and biofilm caused by bacterial quorum-sensing (QS) systems have posed a significant challenge to the development of the food industry. Quorum-quenching (QQ) enzymes can block QS by hydrolyzing or modifying the signal molecule, making these enzymes promising new candidates for use as antimicrobials. With many recent studies of QQ enzymes and their potential to target foodborne bacteria, an updated and systematic review is necessary. Thus, the goals of this review were to summarize what is known about the effects of bacterial QS on the food industry; discuss the current understanding of the catalytic mechanisms of QQ enzymes, including lactonase, acylase, and oxidoreductase; and describe strategies for the engineering and evolution of QQ enzymes for practical use. In particular, this review focuses on the latest progress in the application of QQ enzymes in the field of food. Finally, the current challenges limiting the systematic application of QQ enzymes in the food industry are discussed to help guide the future development of these important enzymes.
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Affiliation(s)
- Dangfeng Wang
- College of Food Science and Technology, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Bohai University, Jinzhou, China
| | - Fangchao Cui
- College of Food Science and Technology, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Bohai University, Jinzhou, China
| | - Likun Ren
- College of Food Science and Technology, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Bohai University, Jinzhou, China
- Key Laboratory of Food Science and Engineering of Heilongjiang Province, College of Food Engineering, Harbin University of Commerce, Harbin, China
| | - Jianrong Li
- College of Food Science and Technology, National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Bohai University, Jinzhou, China
| | - Tingting Li
- Key Laboratory of Biotechnology and Bioresources Utilization, Dalian Minzu University, Ministry of Education, Dalian, China
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9
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Juhas M. Communication Between Microorganisms. BRIEF LESSONS IN MICROBIOLOGY 2023:27-41. [DOI: 10.1007/978-3-031-29544-7_3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 09/02/2023]
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10
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Li J, Ma J, Liao H, Li X, Shen L, Lin H, Sun L, Ou R, He D. Hot-pressed membrane assemblies enhancing the biofilm formation and nitrogen removal in a membrane-aerated biofilm reactor. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 833:155003. [PMID: 35390370 DOI: 10.1016/j.scitotenv.2022.155003] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/07/2022] [Revised: 03/23/2022] [Accepted: 03/30/2022] [Indexed: 06/14/2023]
Abstract
Membrane-aerated biofilm reactor (MABR) is gaining popularity in wastewater treatment as a result of the low-energy delivery of oxygen from the carrier side and reduced sludge waste production, although its wider application suffers from the difficulty in microbial colonization on the smooth, hydrophobic membrane surface. In this study, a newly designed membrane/non-woven fabric assembly, prepared via a facile hot-pressing method, is demonstrated to be efficient in promoting the biofilm formation and nitrogen removal in MABR. The assembly achieved rough surface structure to retain biomass whilst sustained the surface hydrophobicity for a high oxygen transfer ability, which is crucial to support a resilient biofilm. Compared with the slower biomass growth and severe detachment of biofilm in the control, a thicker biofilm was quickly developed on the hot-pressed membrane assembly. High loading rates of organic matter, ammonia nitrogen and total nitrogen (TN) in the MABR using the hot-pressed membrane were 154.9 ± 5.4 g COD/(m2·d), 25.5 ± 0.6 g N/(m2·d) and 22.6 ± 0.7 g N/(m2·d), respectively. Particularly, the removal efficiency of TN was up to 82.8%, which was 2.5 times higher than the control. Furthermore, the biofilm grown on the hot-pressed membrane assembly organized a stable microbial community structure with a steady evolution to achieve a synergistic denitrifying function. Among the bacterial phylotypes, OLB8 might be crucial in denitrification. This study highlighted the significance of this facile membrane modification method to improve the process performance of MABR in wastewater treatment.
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Affiliation(s)
- Jibin Li
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Jinxing Ma
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, PR China
| | - Huaiyu Liao
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Xianhui Li
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, PR China
| | - Liguo Shen
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, PR China
| | - Hongjun Lin
- College of Geography and Environmental Sciences, Zhejiang Normal University, Jinhua 321004, PR China
| | - Li Sun
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Rui Ou
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, PR China
| | - Di He
- Key Laboratory for City Cluster Environmental Safety and Green Development of the Ministry of Education, School of Ecology, Environment and Resources, Guangdong University of Technology, Guangzhou 510006, PR China; Southern Marine Science and Engineering Guangdong Laboratory (Guangzhou), Guangzhou 511458, PR China.
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11
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Li L, Qi C, Wei Q, Zhang L, Fu H, Jiang X, Lu F, Sun F. BaeR overexpression enhances the susceptibility of acrB deleted Salmonella enterica serovar Typhimurium to polymyxin. Vet Microbiol 2022; 274:109552. [DOI: 10.1016/j.vetmic.2022.109552] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/10/2022] [Revised: 07/17/2022] [Accepted: 08/25/2022] [Indexed: 11/27/2022]
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12
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Yan C, Li X, Zhang G, Bi J, Hao H, Hou H. Quorum Sensing (QS)-regulated target predictions of Hafnia alvei H4 based on the joint application of genome and STRING database. Food Res Int 2022; 157:111356. [DOI: 10.1016/j.foodres.2022.111356] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2022] [Revised: 05/03/2022] [Accepted: 05/10/2022] [Indexed: 11/25/2022]
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13
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Wang D, Cui F, Ren L, Tan X, Lv X, Li Q, Li J, Li T. Complete Genome Analysis Reveals the Quorum Sensing-Related Spoilage Potential of Pseudomonas fluorescens PF08, a Specific Spoilage Organism of Turbot ( Scophthalmus maximus). Front Microbiol 2022; 13:856802. [PMID: 35516425 PMCID: PMC9062736 DOI: 10.3389/fmicb.2022.856802] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/17/2022] [Accepted: 02/18/2022] [Indexed: 11/13/2022] Open
Abstract
Pseudomonas fluorescens is a common specific spoilage organism (SSO) of aquatic products. The spoilage ability of SSO can be regulated by the quorum sensing (QS) system. However, the QS system in P. fluorescens and their relationship with the spoilage potential have not been systematically analyzed. In the present study, the complete genome of P. fluorescens PF08 isolated from spoilage turbot was sequenced. The identification of key genes that involved in the QS, enzyme synthesis, sulfur, and amino acid metabolism explained the spoilage potential of P. fluorescens PF08. Results of quantitative real-time PCR revealed the key role of the P. fluorescens PF08 QS system in regulating the transcription of spoilage-related genes and its sensitivity to environmental stress. These findings provide insight into the spoilage features of P. fluorescens PF08 from a genomic perspective. The knowledge may be valuable in the development of new strategies for the targeted inhibition of aquatic product spoilage based on QS interference.
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Affiliation(s)
- Dangfeng Wang
- School of Food Science and Technology, Jiangnan University, Wuxi, China.,College of Food Science and Technology, Bohai University, Jinzhou, China.,National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Fangchao Cui
- College of Food Science and Technology, Bohai University, Jinzhou, China.,National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Likun Ren
- Key Laboratory of Food Science and Engineering of Heilongjiang Province, College of Food Engineering, Harbin University of Commerce, Harbin, China
| | - Xiqian Tan
- College of Food Science and Technology, Bohai University, Jinzhou, China.,National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Xinran Lv
- College of Food Science and Technology, Bohai University, Jinzhou, China.,National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Qiuying Li
- College of Food Science and Technology, Bohai University, Jinzhou, China.,National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Jianrong Li
- School of Food Science and Technology, Jiangnan University, Wuxi, China.,College of Food Science and Technology, Bohai University, Jinzhou, China.,National & Local Joint Engineering Research Center of Storage, Processing and Safety Control Technology for Fresh Agricultural and Aquatic Products, Jinzhou, China
| | - Tingting Li
- Key Laboratory of Biotechnology and Bioresources Utilization, Ministry of Education, Dalian Minzu University, Dalian, China
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14
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Wang YH, Kong WL, Zhu ML, Dai Y, Wu XQ. Colonization by the Mycorrhizal Helper Bacillus pumilus HR10 Is Enhanced During the Establishment of Ectomycorrhizal Symbiosis Between Hymenochaete sp. Rl and Pinus thunbergii. Front Microbiol 2022; 13:818912. [PMID: 35330763 PMCID: PMC8940532 DOI: 10.3389/fmicb.2022.818912] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Accepted: 02/09/2022] [Indexed: 12/02/2022] Open
Abstract
There are complex interactions between mycorrhizal helper bacteria (MHBs) and ectomycorrhizal (ECM) fungi, with MHBs promoting mycorrhizal synthesis and ECM fungi regulating plant rhizobacterial colonization, diversity, and function. In this study, to investigate whether the ECM fungus Hymenochaete sp. Rl affects the survival and colonization of the MHB strain Bacillus pumilus HR10 in the rhizosphere, the biomass of B. pumilus HR10 was measured in the rhizosphere and mycorrhizosphere. In addition, extracts of Hymenochaete sp. Rl and Pinus thunbergii were evaluated for their effect on B. pumilus HR10 colonization (growth, sporulation, biofilm formation, extracellular polysaccharide and extracellular protein contents, flagellar motility, and expression of colonization-related genes). The results showed that inoculation of Hymenochaete sp. Rl significantly increased the biomass of B. pumilus HR10 in the rhizosphere; however, while extracts of Hymenochaete sp. Rl and P. thunbergii did not affect the biomass or spore formation of HR10, they did affect its biofilm formation, extracellular polysaccharide and extracellular protein production, and flagellar motility. Furthermore, the addition of symbiont extracts affected the expression of chemotaxis-related genes in HR10. When the extracts were added separately, the expression of srf genes in HR10 increased; when the extracts were added simultaneously, the expression of the flagellin gene fliG in HR10 increased, but there was no significant effect on the expression of srf genes, consistent with the results on biofilm production. Thus, Hymenochaete sp. Rl and P. thunbergii roots had a positive effect on colonization by B. pumilus HR10 at the rhizosphere level through their secretions.
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Affiliation(s)
- Ya-Hui Wang
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, China
| | - Wei-Liang Kong
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, China
| | - Mei-Ling Zhu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, China
| | - Yun Dai
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, China
| | - Xiao-Qin Wu
- Co-Innovation Center for Sustainable Forestry in Southern China, College of Forestry, Nanjing Forestry University, Nanjing, China.,Jiangsu Key Laboratory for Prevention and Management of Invasive Species, Nanjing Forestry University, Nanjing, China
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15
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Dai J, Fang L, Wu Y, Liu B, Cheng X, Yao M, Huang L. Effects of exogenous AHLs on the spoilage characteristics of
Pseudomonas koreensis
PS1. J Food Sci 2022; 87:819-832. [DOI: 10.1111/1750-3841.16038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2021] [Revised: 12/03/2021] [Accepted: 12/15/2021] [Indexed: 11/28/2022]
Affiliation(s)
- Jinyue Dai
- College of Biological Science and Engineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources Institute of Applied Microbiology Nanchang China
| | - Limin Fang
- College of Biological Science and Engineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources Institute of Applied Microbiology Nanchang China
| | - Yan Wu
- College of Biological Science and Engineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources Institute of Applied Microbiology Nanchang China
| | - Baoyu Liu
- College of Biological Science and Engineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources Institute of Applied Microbiology Nanchang China
| | - Xin Cheng
- College of Biological Science and Engineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources Institute of Applied Microbiology Nanchang China
| | - Mingyin Yao
- College of Engineering, Jiangxi Agricultural University Jiangxi Key Laboratory of Modern Agricultural Equipment Nanchang China
| | - Lin Huang
- College of Biological Science and Engineering, Jiangxi Agricultural University, Jiangxi Engineering Laboratory for the Development and Utilization of Agricultural Microbial Resources Institute of Applied Microbiology Nanchang China
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16
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N-acyl-homoserine lactone produced by Rahnella inusitata isolated from the gut of Galleria mellonella influences Salmonella phenotypes. Braz J Microbiol 2022; 53:819-829. [PMID: 35048318 PMCID: PMC9151966 DOI: 10.1007/s42770-022-00681-w] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 01/10/2022] [Indexed: 02/01/2023] Open
Abstract
The most studied mechanism of quorum sensing in Gram-negative bacteria is mediated by autoinducer 1 (AI-1), namely, acyl-homoserine lactone (AHL). This system allows communication among different bacterial species and regulates the expression of virulence genes in many pathogens. Although AHL-producing bacteria have been detected in the intestines of humans and other animals, no report was found about AHL-producing bacteria in the insect gut and the possible effects of these autoinducers on enteropathogenic bacteria. Therefore, this study aimed to identify AHL-producing bacteria in the gut of larvae of Galleria mellonella and to evaluate the influence of this quorum sensing signal on the regulation of adhesion and motility phenotypes in the intestinal pathogen Salmonella. Sequencing of the 16S rRNA gene, 16S rRNA gene-based phylogenetic analyses, and phenotypic characterization of gut isolates was performed. The profile of AHLs produced by the isolates was determined using thin-layer chromatography (TLC) and revealed with the biosensor strain Chromobacterium violaceum CV026. Sequencing, phylogenetic analyses and phenotypic characterization of gut isolates showed that the three AHL-producing strains belong to the species Rahnella inusitata, named GM34, GM56, and GM60. The TLC showed that R. inusitata produces a six-carbon AHL. In the presence of cell-free extract of R. inusitata containing AHL and under anaerobic conditions, Salmonella enterica increased the adhesion to stainless steel coupons and presented swarming motility. Extracts from the culture medium of R. inusitata isolates containing AHL increased the adhesion on stainless steel coupons and swarming motility of Salmonella enterica serovar Enteritidis PT4 under anaerobic conditions. The results suggest the possibility of communication between members of the G. mellonella intestinal microbiota with pathogens such as Salmonella.
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17
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Ma X, Zhang Y, Li X, Bi J, Zhang G, Hao H, Hou H. Impacts of salt-tolerant Staphylococcus nepalensis 5-5 on bacterial composition and biogenic amines accumulation in fish sauce fermentation. Int J Food Microbiol 2022; 361:109464. [PMID: 34749187 DOI: 10.1016/j.ijfoodmicro.2021.109464] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/16/2021] [Revised: 10/19/2021] [Accepted: 11/01/2021] [Indexed: 12/28/2022]
Abstract
High levels of biogenic amines (BAs) in fermented food can present a health risk to consumers. Microorganisms that can reduce BAs are widely used in fermented foods. However, the mechanism by which microorganisms reduce BAs in foods has not been explored. In this study, we investigated how Staphylococcus nepalensis 5-5 (S. nepalensis 5-5), which was a BA-degrading strain isolated from fish sauce, could reduce BA accumulation in the fish sauce. High-throughput sequencing and HPLC methods were sequentially used to determine the microbial community structure and BA content in fish sauce with/without S. nepalensis 5-5. The results showed that S. nepalensis 5-5 might be a safe strain that could improve the flavor of fish sauce while still exhibiting good BA degradation ability under a high salt environment. The content of BAs in fish sauce inoculated with S. nepalensis 5-5 was significantly decreased compared with the control fish sauce, achieving maximal reductions of 15.74, 14.18 and 16.65% in putrescine, cadaverine and histamine accumulation, respectively. According to high-throughput sequencing data, S. nepalensis 5-5 reduced the abundance of the genera positively associated with BAs, while increasing the number of bacterial genera negatively correlated with BAs in the sample and changed the correlation between some genera and BAs via species interaction. In addition, analysis of amino acid metabolism showed that S. nepalensis 5-5 might use histidine to produce metabolites other than histamine, thereby reducing the production of BAs. These findings not only explained the mechanisms by which the BA level in fish sauce could be reduced but also provided a potential means to control BA production in the fish sauce during the fermentation stage.
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Affiliation(s)
- Xinxiu Ma
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China; Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian Polytechnic University, Dalian 116034, China
| | - Yanan Zhang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China; Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian Polytechnic University, Dalian 116034, China
| | - Xinyu Li
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China; Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian Polytechnic University, Dalian 116034, China
| | - Jingran Bi
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China; Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian Polytechnic University, Dalian 116034, China
| | - Gongliang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China; Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian Polytechnic University, Dalian 116034, China
| | - Hongshun Hao
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian Polytechnic University, Dalian 116034, China
| | - Hongman Hou
- School of Food Science and Technology, Dalian Polytechnic University, Dalian 116034, China; Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian Polytechnic University, Dalian 116034, China.
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18
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Woo K, Kim DH, Oh MH, Park HS, Choi CH. N-3-Hydroxy Dodecanoyl-DL-homoserine Lactone (OH-dDHL) Triggers Apoptosis of Bone Marrow-Derived Macrophages through the ER- and Mitochondria-Mediated Pathways. Int J Mol Sci 2021; 22:ijms22147565. [PMID: 34299184 PMCID: PMC8305837 DOI: 10.3390/ijms22147565] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/21/2021] [Revised: 07/11/2021] [Accepted: 07/13/2021] [Indexed: 02/06/2023] Open
Abstract
Quorum sensing of Acinetobacter nosocomialis for cell-to-cell communication produces N-3-hydroxy dodecanoyl-DL-homoserine lactone (OH-dDHL) by an AnoR/I two-component system. However, OH-dDHL-driven apoptotic mechanisms in hosts have not been clearly defined. Here, we investigated the induction of apoptosis signaling pathways in bone marrow-derived macrophages treated with synthetic OH-dDHL. Moreover, the quorum-sensing system for virulence regulation was evaluated in vivo using wild-type and anoI-deletion mutant strains. OH-dDHL decreased the viability of macrophage and epithelial cells in dose- and time-dependent manners. OH-dDHL induced Ca2+ efflux and caspase-12 activation by ER stress transmembrane protein (IRE1 and ATF6a p50) aggregation and induced mitochondrial dysfunction through reactive oxygen species (ROS) production, which caused cytochrome c to leak. Pretreatment with a pan-caspase inhibitor reduced caspase-3, -8, and -9, which were activated by OH-dDHL. Pro-inflammatory cytokine and paraoxonase-2 (PON2) gene expression were increased by OH-dDHL. We showed that the anoI-deletion mutant strains have less intracellular invasion compared to the wild-type strain, and their virulence, such as colonization and dissemination, was decreased in vivo. Consequently, these findings revealed that OH-dDHL, as a virulence factor, contributes to bacterial infection and survival as well as the modification of host responses in the early stages of infection.
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Affiliation(s)
- Kyungho Woo
- Department of Microbiology and Medical Science, Chungnam National University School of Medicine, Daejeon 35015, Korea; (K.W.); (D.H.K.); (H.S.P.)
| | - Dong Ho Kim
- Department of Microbiology and Medical Science, Chungnam National University School of Medicine, Daejeon 35015, Korea; (K.W.); (D.H.K.); (H.S.P.)
| | - Man Hwan Oh
- Department of Microbiology, Dankook University, Cheonan 31116, Korea;
| | - Ho Sung Park
- Department of Microbiology and Medical Science, Chungnam National University School of Medicine, Daejeon 35015, Korea; (K.W.); (D.H.K.); (H.S.P.)
| | - Chul Hee Choi
- Department of Microbiology and Medical Science, Chungnam National University School of Medicine, Daejeon 35015, Korea; (K.W.); (D.H.K.); (H.S.P.)
- Correspondence: ; Tel.: +82-42-580-8246
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19
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Bassey AP, Ye K, Li C, Zhou G. Transcriptomic-proteomic integration: A powerful synergy to elucidate the mechanisms of meat spoilage in the cold chain. Trends Food Sci Technol 2021. [DOI: 10.1016/j.tifs.2021.02.051] [Citation(s) in RCA: 7] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/26/2022]
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20
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Yan C, Li X, Zhang G, Zhu Y, Bi J, Hao H, Hou H. Quorum Sensing-Mediated and Growth Phase-Dependent Regulation of Metabolic Pathways in Hafnia alvei H4. Front Microbiol 2021; 12:567942. [PMID: 33737914 PMCID: PMC7960787 DOI: 10.3389/fmicb.2021.567942] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Accepted: 01/26/2021] [Indexed: 11/13/2022] Open
Abstract
Quorum sensing (QS) is a widespread regulatory mechanism in bacteria used to coordinate target gene expression with cell density. Thus far, little is known about the regulatory relationship between QS and cell density in terms of metabolic pathways in Hafnia alvei H4. In this study, transcriptomics analysis was performed under two conditions to address this question. The comparative transcriptome of H. alvei H4 wild-type at high cell density (OD600 = 1.7) relative to low cell density (OD600 = 0.3) was considered as growth phase-dependent manner (GPDM), and the transcriptome profile of luxI/R deletion mutant (ΔluxIR) compared to the wild-type was considered as QS-mediated regulation. In all, we identified 206 differentially expressed genes (DEGs) mainly presented in chemotaxis, TCA cycle, two-component system, ABC transporters and pyruvate metabolism, co-regulated by the both density-dependent regulation, and the results were validated by qPCR and swimming phenotypic assays. Aside from the co-regulated DEGs, we also found that 59 DEGs, mediated by density-independent QS, function in pentose phosphate and histidine metabolism and that 2084 cell-density-dependent DEGs involved in glycolysis/gluconeogenesis and phenylalanine metabolism were influenced only by GPDM from significantly enriched analysis of transcriptome data. The findings provided new information about the interplay between two density-dependent metabolic regulation, which could assist with the formulation of control strategies for this opportunistic pathogen, especially at high cell density.
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Affiliation(s)
- Congyang Yan
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Xue Li
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Gongliang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Yaolei Zhu
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Jingran Bi
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Hongshun Hao
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Hongman Hou
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
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21
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Sang X, Ma X, Zhang Y, Hao H, Bi J, Zhang G, Hou H. Assessment of the Distribution and Safety of Tetragenococcus muriaticus for Potential Application in the Preparation of Chinese Grasshopper Sub Shrimp Paste. Front Microbiol 2021; 12:628838. [PMID: 33584630 PMCID: PMC7876237 DOI: 10.3389/fmicb.2021.628838] [Citation(s) in RCA: 9] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/13/2020] [Accepted: 01/07/2021] [Indexed: 11/13/2022] Open
Abstract
The bacterial profiles of 63 grasshopper sub shrimp paste samples collected from seven typical regions around the Bohai Sea were investigated by high-throughput sequencing. Tetragenococcus muriaticus was found to be the prevailing species present in all the samples, and the presence of T. muriaticus also weakly correlated with the histamine content in the samples. Six T. muriaticus strains with low biogenic amine (BA)-producing ability and deficient in histamine production were identified and subjected to safety assessment. All six strains displayed weak resistance to fifteen known antibiotics as based on the Enterococcus breakpoint values. None of the strains exhibited hemolytic activity or biofilm formation. All strains exhibited were able to grow on MRS agar containing 21% NaCl and expressed amine oxidase and strain-specific proteases and lipases. Most of the strains exhibited acid production at 18% NaCl. Moreover, three of the strains (designated as SG, TS, and QH) with histamine degradation ability were inoculated into separate shrimp paste samples to determine their effect on BA accumulation. The results indicated that the addition of T. muriaticus to shrimp pastes not only led to a significant reduction of BA content in the pastes but also improved the flavor of the pastes. Consequently, these strains may be used as potential candidates for controlling the content of histamine in fermented foods.
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Affiliation(s)
- Xue Sang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Xinxiu Ma
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Yanan Zhang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Hongshun Hao
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Jingran Bi
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Gongliang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
| | - Hongman Hou
- School of Food Science and Technology, Dalian Polytechnic University, Dalian, China
- Liaoning Key Lab for Aquatic Processing Quality and Safety, Dalian, China
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22
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Fei C, Ochsenkühn MA, Shibl AA, Isaac A, Wang C, Amin SA. Quorum sensing regulates 'swim-or-stick' lifestyle in the phycosphere. Environ Microbiol 2020; 22:4761-4778. [PMID: 32896070 PMCID: PMC7693213 DOI: 10.1111/1462-2920.15228] [Citation(s) in RCA: 29] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/21/2020] [Revised: 09/03/2020] [Accepted: 09/04/2020] [Indexed: 12/12/2022]
Abstract
Interactions between phytoplankton and bacteria play major roles in global biogeochemical cycles and oceanic nutrient fluxes. These interactions occur in the microenvironment surrounding phytoplankton cells, known as the phycosphere. Bacteria in the phycosphere use either chemotaxis or attachment to benefit from algal excretions. Both processes are regulated by quorum sensing (QS), a cell–cell signalling mechanism that uses small infochemicals to coordinate bacterial gene expression. However, the role of QS in regulating bacterial attachment in the phycosphere is not clear. Here, we isolated a Sulfitobacter pseudonitzschiae F5 and a Phaeobacter sp. F10 belonging to the marine Roseobacter group and an Alteromonas macleodii F12 belonging to Alteromonadaceae, from the microbial community of the ubiquitous diatom Asterionellopsis glacialis. We show that only the Roseobacter group isolates (diatom symbionts) can attach to diatom transparent exopolymeric particles. Despite all three bacteria possessing genes involved in motility, chemotaxis, and attachment, only S. pseudonitzschiae F5 and Phaeobacter sp. F10 possessed complete QS systems and could synthesize QS signals. Using UHPLC–MS/MS, we identified three QS molecules produced by both bacteria of which only 3‐oxo‐C16:1‐HSL strongly inhibited bacterial motility and stimulated attachment in the phycosphere. These findings suggest that QS signals enable colonization of the phycosphere by algal symbionts.
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Affiliation(s)
- Cong Fei
- Marine Microbial Ecology Lab, Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates.,College of Resources and Environmental Science, Nanjing Agriculture University, Nanjing, China
| | - Michael A Ochsenkühn
- Marine Microbial Ecology Lab, Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Ahmed A Shibl
- Marine Microbial Ecology Lab, Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
| | - Ashley Isaac
- Marine Microbial Ecology Lab, Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates.,International Max Planck Research School of Marine Microbiology, University of Bremen, Bremen, Germany
| | - Changhai Wang
- College of Resources and Environmental Science, Nanjing Agriculture University, Nanjing, China
| | - Shady A Amin
- Marine Microbial Ecology Lab, Biology Program, New York University Abu Dhabi, Abu Dhabi, United Arab Emirates
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23
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Zhu Y, Sang X, Li X, Zhang Y, Hao H, Bi J, Zhang G, Hou H. Effect of quorum sensing and quorum sensing inhibitors on the expression of serine protease gene in Hafnia alvei H4. Appl Microbiol Biotechnol 2020; 104:7457-7465. [PMID: 32676711 DOI: 10.1007/s00253-020-10730-9] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2019] [Revised: 05/31/2020] [Accepted: 06/07/2020] [Indexed: 12/01/2022]
Abstract
The serp gene codes for a protease that is considered to be an important factor associated with quorum sensing (QS)-based food spoilage caused by microorganisms. In this study, we evaluated the effect of temperature (4-37 °C) and QS inhibitors on the production of N-acyl-L-homoserine lactones (AHLs) and relative expression of the luxR/I, as well as serp in Hafnia alvei H4. Production of AHLs and expression of luxR/I were found to reach maximum levels at 10 °C, suggesting that the QS system of H. alvei H4 might have higher activity at low temperatures; similar result was also obtained for serp expression. Mutants of H. alvei H4 deficient in QS were used to identify the regulation of QS on serp expression. Significant reduction (P < 0.05) in serp expression was found in the mutants ∆luxR, ∆luxI, and ∆luxR/I, with ∆luxI and ∆luxR/I showing greater reduction than ∆luxR. Minimum inhibition concentrations (MIC) of Benzyl isothiocyanate and 3-Methylthiopropyl isothiocyanate for H. alvei H4 were determined to be 7.813 and 15.625 mM, respectively. Furthermore, the expression of serp, as well as that of luxR and luxI, was significantly repressed (P < 0.05) by the two QS inhibitors at 1/8 MIC and 1/16 MIC, indicating that these inhibitors might repress serp expression through affecting luxR and luxI expression in H. alvei H4. The findings of this study, therefore, suggested that food spoilage caused by H. alvei could be controlled through the application of QS inhibitors.
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Affiliation(s)
- Yaolei Zhu
- School of Food Science and Technology, Dalian Polytechnic University, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China
| | - Xue Sang
- School of Food Science and Technology, Dalian Polytechnic University, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China
| | - Xue Li
- School of Food Science and Technology, Dalian Polytechnic University, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China
| | - Yanan Zhang
- School of Food Science and Technology, Dalian Polytechnic University, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China
| | - Hongshun Hao
- Liaoning Key Lab for Aquatic Processing Quality and Safety, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China
| | - Jingran Bi
- School of Food Science and Technology, Dalian Polytechnic University, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China
| | - Gongliang Zhang
- School of Food Science and Technology, Dalian Polytechnic University, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China.,Liaoning Key Lab for Aquatic Processing Quality and Safety, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China
| | - Hongman Hou
- School of Food Science and Technology, Dalian Polytechnic University, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China. .,Liaoning Key Lab for Aquatic Processing Quality and Safety, No.1, Qinggongyuan, Ganjingzi District, Dalian, Liaoning, People's Republic of China.
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24
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Lianou A, Nychas GJE, Koutsoumanis KP. Strain variability in biofilm formation: A food safety and quality perspective. Food Res Int 2020; 137:109424. [PMID: 33233106 DOI: 10.1016/j.foodres.2020.109424] [Citation(s) in RCA: 32] [Impact Index Per Article: 8.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/24/2020] [Revised: 06/02/2020] [Accepted: 06/05/2020] [Indexed: 12/20/2022]
Abstract
The inherent differences in microbial behavior among identically treated strains of the same microbial species, referred to as "strain variability", are regarded as an important source of variability in microbiological studies. Biofilms are defined as the structured multicellular communities with complex architecture that enable microorganisms to grow adhered to abiotic or living surfaces and constitute a fundamental aspect of microbial ecology. The research studies assessing the strain variability in biofilm formation are relatively few compared to the ones evaluating other aspects of microbial behavior such as virulence, growth and stress resistance. Among the available research data on intra-species variability in biofilm formation, compiled and discussed in the present review, most of them refer to foodborne pathogens as compared to spoilage microorganisms. Molecular and physiological aspects of biofilm formation potentially related to strain-specific responses, as well as information on the characterization and quantitative description of this type of biological variability are presented and discussed. Despite the considerable amount of available information on the strain variability in biofilm formation, there are certain data gaps and still-existing challenges that future research should cover and address. Current and future advances in systems biology and omics technologies are expected to aid significantly in the explanation of phenotypic strain variability, including biofilm formation variability, allowing for its integration in microbiological risk assessment.
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Affiliation(s)
- Alexandra Lianou
- Laboratory of Microbiology and Biotechnology of Foods, Department of Food Science and Human Nutrition, School of Food and Nutritional Sciences, Agricultural University of Athens, Athens 11855, Greece
| | - George-John E Nychas
- Laboratory of Microbiology and Biotechnology of Foods, Department of Food Science and Human Nutrition, School of Food and Nutritional Sciences, Agricultural University of Athens, Athens 11855, Greece
| | - Konstantinos P Koutsoumanis
- Laboratory of Food Microbiology and Hygiene, Department of Food Science and Technology, School of Agriculture, Forestry and Natural Environment, Aristotle University of Thessaloniki, Thessaloniki 54124, Greece.
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25
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Park H, Do E, Kim M, Park HJ, Lee J, Han SW. A LysR-Type Transcriptional Regulator LcrX Is Involved in Virulence, Biofilm Formation, Swimming Motility, Siderophore Secretion, and Growth in Sugar Sources in Xanthomonas axonopodis Pv. glycines. FRONTIERS IN PLANT SCIENCE 2020; 10:1657. [PMID: 31998344 PMCID: PMC6965072 DOI: 10.3389/fpls.2019.01657] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/03/2019] [Accepted: 11/25/2019] [Indexed: 05/30/2023]
Abstract
Xanthomonas axonopodis pv. glycines (Xag) is a Gram-negative bacterium that causes bacterial pustule disease in soybean. To acclimate to new environments, the expression of genes in bacteria is controlled directly or indirectly by diverse transcriptional factors. Among them, LysR type transcriptional regulators are well-characterized and abundant in bacteria. In a previous study, comparative proteomic analysis revealed that LysR type carbohydrate-related transcriptional regulator in Xag (LcrX) was more abundant in XVM2, which is a minimal medium, compared with a rich medium. However, the functions of LcrX in Xag have not been characterized. In this study, we generated an LcrX-overexpressing strain, Xag(LcrX), and the knockout mutant strain, XagΔlcrX(EV), to elucidate the functions of LcrX. Bacterial multiplication of Xag(LcrX) in soybean was significantly impaired, indicating that LcrX is related to virulence. Comparative proteomic analysis revealed that LcrX is mainly involved in carbohydrate metabolism/transport and inorganic ion transport/metabolism. Based on the results of proteomics analysis, diverse phenotypic assays were carried out. A gel electrophoresis mobility shift assay demonstrated that LcrX specifically bound to the putative promoter regions of genes encoding putative fructose 1,6-bisphosphatase and protease. Through a 96-well plate assay under various conditions, we confirmed that the growth of Xag(LcrX) was dramatically affected in the presence of various carbon sources, while the growth of XagΔlcrX(EV) was only slightly changed. Biofilm formation activity was reduced in Xag(LcrX) but enhanced in XagΔlcrX(EV). The production of siderophores was also decreased in Xag(LcrX) but not altered in XagΔlcrX(EV). In contrast, LcrX was not associated with exopolysaccharide production, protease activity, or bacterial motility. These findings provide new insights into the functions of a carbohydrate-related transcriptional regulator in Xag.
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Affiliation(s)
- Hanbi Park
- Department of Plant Science and Technology, Chung-Ang University, Anseong, South Korea
| | - Eunsoo Do
- Department of Systems Biotechnology, Chung-Ang University, Anseong, South Korea
| | - Minyoung Kim
- Department of Plant Science and Technology, Chung-Ang University, Anseong, South Korea
| | - Hye-Jee Park
- Department of Plant Science and Technology, Chung-Ang University, Anseong, South Korea
| | - Jongchan Lee
- Department of Plant Science and Technology, Chung-Ang University, Anseong, South Korea
| | - Sang-Wook Han
- Department of Plant Science and Technology, Chung-Ang University, Anseong, South Korea
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26
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Li X, Zhang G, Zhu Y, Bi J, Hao H, Hou H. Effect of the luxI/R gene on AHL-signaling molecules and QS regulatory mechanism in Hafnia alvei H4. AMB Express 2019; 9:197. [PMID: 31807954 PMCID: PMC6895348 DOI: 10.1186/s13568-019-0917-z] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2019] [Accepted: 11/22/2019] [Indexed: 01/03/2023] Open
Abstract
Hafnia alvei H4 is a bacterium subject to regulation by a N-acyl-l-homoserine lactone (AHL)-mediated quorum sensing system and is closely related to the corruption of instant sea cucumber. Studying the effect of Hafnia alvei H4 quorum sensing regulatory genes on AHLs is necessary for the quality and preservation of instant sea cucumber. In this study, the draft genome of H. alvei H4, which comprises a single chromosome of 4,687,151 bp, was sequenced and analyzed and the types of AHLs were analyzed employing thin-layer chromatography (TLC) and high resolution triple quadrupole liquid chromatography/mass spectrometry (LC/MS). Then the wild-type strain of H. alvei H4 and the luxI/R double mutant (ΔluxIR) were compared by transcriptome sequencing (RNA-seq). The results indicate that the incomplete genome sequence revealed the presence of one quorum-sensing (QS) gene set, designated as lasI/expR. Three major AHLs, N-hexanoyl-l-homoserine lactone (C6-HSL), N-butyryl-l-homoserine lactone (C4-HSL), and N-(3-oxo-octanoyl)-l-homoserine lactone (3-oxo-C8-HSL) were found, with C6-HSL being the most abundant. C6-HSL was not detected in the culture of the luxI mutant (ΔluxI) and higher levels of C4-HSL was found in the culture of the luxR mutant (ΔluxR), which suggested that the luxR gene may have a positive effect on C4-HSL production. It was also found that AHL and QS genes are closely related in the absence of luxIR double deletion. The results of this study can further elucidate at the genetic level that luxI and luxR genes are involved in the regulation of AHL.
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