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Bai Y, Zhou Y, Chang R, Hu X, Zhou Y, Chen J, Zhang Z, Yao J. Transcription profiles and phenotype reveal global response of Staphylococcus aureus exposed to ultrasound and ultraviolet stressors. THE SCIENCE OF THE TOTAL ENVIRONMENT 2024; 912:169146. [PMID: 38061661 DOI: 10.1016/j.scitotenv.2023.169146] [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: 08/24/2023] [Revised: 11/05/2023] [Accepted: 12/04/2023] [Indexed: 12/19/2023]
Abstract
Ultrasound and ultraviolet light have good inactivation performance against pathogens in sewage. In this study, the inactivation mechanisms of 60 kHz ultrasound and ultraviolet radiation against Staphylococcus aureus (S. aureus) were studied from the perspectives of cell phenotype and transcriptome for the first time. The results showed that both ultrasound and ultraviolet treatments had adverse impacts on the cellular morphology of S. aureus to varying degrees at cellular level. The transcriptomic analysis revealed that there were 225 and 1077 differentially expressed genes (DEGs) in the ultrasound and ultraviolet treatments, respectively. The result revealed that both ultrasound and ultraviolet could interfere with the expression of the genes involved in ABC transporters, amino acid and fatty acid metabolism to influence the membrane permeability. Besides the membrane permeability, ultraviolet also could disturb the ATP synthesis, DNA replication and cell division through restraining the expression of several genes related to carbohydrate metabolism, peptidoglycan synthesis, DNA-binding/repair protein synthesis. Compared with the single inactivation pathway of ultrasound, ultraviolet inactivation of S. aureus is multi-target and multi-pathway. We believe that the bactericidal mechanisms of ultrasound and ultraviolet radiation presented by this study could provide theoretical guidance for the synergistic inactivation of pathogens in sewage by ultrasound and ultraviolet radiation in the future.
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Affiliation(s)
- Yun Bai
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yuanhang Zhou
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Ruiting Chang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Xueli Hu
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Yingying Zhou
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Jiabo Chen
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China
| | - Zhi Zhang
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
| | - Juanjuan Yao
- Key Laboratory of Three Gorges Reservoir Region's Eco-Environment, Ministry of Education, Chongqing University, Chongqing 400045, China; College of Environment and Ecology, Chongqing University, Chongqing 400045, China.
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Zhao F, Xu H, Chen Y, Xiao J, Zhang M, Li Z, Liu J, Qi C. Actinobacillus pleuropneumoniae FliY and YdjN are involved in cysteine/cystine utilization, oxidative resistance, and biofilm formation but are not determinants of virulence. Front Microbiol 2023; 14:1169774. [PMID: 37250053 PMCID: PMC10213525 DOI: 10.3389/fmicb.2023.1169774] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2023] [Accepted: 04/10/2023] [Indexed: 05/31/2023] Open
Abstract
Introduction Actinobacillus pleuropneumoniae (A. pleuropneumoniae) is a member of Actinobacillus in family Pasteurellaceae. It is the causative agent of porcine pleuropneumonia, which has caused huge economic losses to pig industry over the world. Cysteine is a precursor of many important biomolecules and defense compounds in the cell. However, molecular mechanisms of cysteine transport in A. pleuropneumoniae are unclear. Methods In this study, gene-deleted mutants were generated and investigated, to reveal the roles of potential cysteine/cystine transport proteins FliY and YdjN of A. pleuropneumoniae. Results Our results indicated that the growth of A. pleuropneumoniae was not affected after fliY or ydjN single gene deletion, but absence of both FliY and YdjN decreased the growth ability significantly, when cultured in the chemically defined medium (CDM) supplemented with cysteine or cystine as the only sulfur source. A. pleuropneumoniae double deletion mutant ΔfliYΔydjN showed increased sensitivity to oxidative stress. Besides, trans-complementation of YdjN into ΔfliYΔydjN and wild type leads to increased biofilm formation in CDM. However, the virulence of ΔfliYΔydjN was not attenuated in mice or pigs. Discussion These findings suggest that A. pleuropneumoniae FliY and YdjN are involved in the cysteine/cystine acquisition, oxidative tolerance, and biofilm formation, but not contribute to the pathogenicity of A. pleuropneumoniae.
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Cai DS, Yang XY, Yang YQ, Gao F, Cheng XH, Zhao YJ, Qi R, Zhang YZ, Lu JH, Lin XY, Liu YJ, Xu B, Wang PL, Lei HM. Design and synthesis of novel anti-multidrug-resistant staphylococcus aureus derivatives of glycyrrhetinic acid by blocking arginine biosynthesis, metabolic and H 2S biogenesis. Bioorg Chem 2023; 131:106337. [PMID: 36603244 DOI: 10.1016/j.bioorg.2022.106337] [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: 08/03/2022] [Revised: 12/12/2022] [Accepted: 12/22/2022] [Indexed: 12/31/2022]
Abstract
With the soaring number of multidrug-resistant bacteria, it is imperative to develop novel efficient antibacterial agents and discovery new antibacterial pathways. Herein, we designed and synthesized a series of structurally novel glycyrrhetinic acid (GA) derivatives against multidrug-resistant Staphylococcus aureus (MRSA). The in vitro antibacterial activity of these compounds was evaluated using the microbroth dilution method, agar plate coating experiments and real-time growth curves, respectively. Most of the target derivatives showed moderate antibacterial activity against Staphylococcus aureus (S. aureus) and MRSA (MIC = 3.125-25 μM), but inactivity against Escherichia coli (E. Coli) and Pseudomonas aeruginosa (P. aeruginosa) (MIC > 200 μM). Among them, compound 11 had the strongest antibacterial activity against MRSA, with an MIC value of 3.125 μM, which was 32 times and 64 times than the first-line antibiotics penicillin and norfloxacin, respectively. Additionally, transcriptomic (RNA-seq) and quantitative polymerase chain reaction (qPCR) analysis revealed that the antibacterial mechanism of compound 11 was through blocking the arginine biosynthesis and metabolic and the H2S biogenesis. Importantly, compound 11 was confirmed to have good biocompatibility through the in vitro hemolysis tests, cytotoxicity assays and the in vivo quail chicken chorioallantoic membrane (qCAM) experiments. Current study provided new potential antibacterial candidates from glycyrrhetinic acid derivatives for clinical treatment of MRSA infections.
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Affiliation(s)
- De-Sheng Cai
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Xiao-Yun Yang
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Yu-Qin Yang
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Feng Gao
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Xue-Hao Cheng
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Ya-Juan Zhao
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Rui Qi
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Yao-Zhi Zhang
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Ji-Hui Lu
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Xiao-Yu Lin
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Yi-Jing Liu
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China
| | - Bing Xu
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China.
| | - Peng-Long Wang
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China.
| | - Hai-Min Lei
- School of Chinese Pharmacy, Beijing University of Chinese Medicine, Beijing 102488, PR China.
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Chen Y, Yang Z, Zhou X, Jin M, Dai Z, Ming D, Zhang Z, Zhu L, Jiang L. Sequence, structure, and function of the Dps DNA-binding protein from Deinococcus wulumuqiensis R12. Microb Cell Fact 2022; 21:132. [PMID: 35780107 PMCID: PMC9250271 DOI: 10.1186/s12934-022-01857-7] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2021] [Accepted: 06/21/2022] [Indexed: 11/28/2022] Open
Abstract
Deinococcus wulumuqiensis R12, which was isolated from arid irradiated soil in Xinjiang province of China, belongs to a genus that is well-known for its extreme resistance to ionizing radiation and oxidative stress. The DNA-binding protein Dps has been studied for its great contribution to oxidative resistance. To explore the role of Dps in D. wulumuqiensis R12, the Dps sequence and homology-modeled structure were analyzed. In addition, the dps gene was knocked out and proteomics was used to verify the functions of Dps in D. wulumuqiensis R12. Docking data and DNA binding experiments in vitro showed that the R12 Dps protein has a better DNA binding ability than the Dps1 protein from D. radiodurans R1. When the dps gene was deleted in D. wulumuqiensis R12, its resistance to H2O2 and UV rays was greatly reduced, and the cell envelope was destroyed by H2O2 treatment. Additionally, the qRT-PCR and proteomics data suggested that when the dps gene was deleted, the catalase gene was significantly down-regulated. The proteomics data indicated that the metabolism, transport and oxidation–reduction processes of D. wulumuqiensis R12 were down-regulated after the deletion of the dps gene. Overall, the data conformed that Dps protein plays an important role in D. wulumuqiensis R12.
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Affiliation(s)
- Yao Chen
- College of Food Science and Light Industry, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China.,College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Zhihan Yang
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Xue Zhou
- College of Food Science and Light Industry, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Mengmeng Jin
- College of Food Science and Light Industry, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Zijie Dai
- College of Food Science and Light Industry, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Dengming Ming
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China
| | - Zhidong Zhang
- College of Biotechnology and Pharmaceutical Engineering, Nanjing Tech University, Nanjing, 211816, China. .,Institute of Applied Microbiology, Xinjiang Academy of Agricultural Sciences/Xinjiang Key Laboratory of Special Environmental Microbiology, Ürümqi, 830091, Xinjiang, China.
| | - Liying Zhu
- School of Chemistry and Molecular Engineering, Nanjing Tech University, Nanjing, 211816, China.
| | - Ling Jiang
- College of Food Science and Light Industry, State Key Laboratory of Materials-Oriented Chemical Engineering, Nanjing Tech University, Nanjing, 211816, China.
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Abstract
CyuA of Escherichia coli is an inducible desulfidase that degrades cysteine to pyruvate, ammonium, and hydrogen sulfide. Workers have conjectured that its role may be to defend bacteria against the toxic effects of cysteine. However, cyuA sits in an operon alongside cyuP, which encodes a cysteine importer that seems ill suited to protecting the cell from environmental cysteine. In this study, transport measurements established that CyuP is a cysteine-specific, high-flux importer. The concerted action of CyuP and CyuA allowed anaerobic E. coli to employ cysteine as either the sole nitrogen or the sole carbon/energy source. CyuA was essential for this function, and although other transporters can slowly bring cysteine into the cell, CyuP-proficient cells outcompeted cyuP mutants. Cells immediately consumed the ammonia and pyruvate that CyuA generated, with little or none escaping from the cell. The expression of the cyuPA operon depended upon both CyuR, a cysteine-activated transcriptional activator, and Crp. This control is consistent with its catabolic function. In fact, the cyuPA operon sits immediately downstream of the thrABCDEFG operon, which allows the analogous fermentation of serine and threonine; this arrangement suggests that this gene cluster may have moved jointly through the anaerobic biota, providing E. coli with the ability to ferment a limited set of amino acids. Interestingly, both the cyu- and thr-encoded pathways depend upon oxygen-sensitive enzymes and cannot contribute to amino acid catabolism in oxic environments.
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Shao L, Liu Y, Zhao Y, Zou B, Li X, Dai R. Integrated transcriptomic and metabolomic analysis of the global response of Staphylococcus aureus to ohmic heating. INNOV FOOD SCI EMERG 2021. [DOI: 10.1016/j.ifset.2021.102870] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/06/2023]
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Kuznetsova A, Masrati G, Vigonsky E, Livnat-Levanon N, Rose J, Grupper M, Baloum A, Yang JG, Rees DC, Ben-Tal N, Lewinson O. Titratable transmembrane residues and a hydrophobic plug are essential for manganese import via the Bacillus anthracis ABC transporter MntBC-A. J Biol Chem 2021; 297:101087. [PMID: 34416234 PMCID: PMC8487065 DOI: 10.1016/j.jbc.2021.101087] [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: 02/09/2021] [Revised: 08/12/2021] [Accepted: 08/16/2021] [Indexed: 11/07/2022] Open
Abstract
All extant life forms require trace transition metals (e.g., Fe2/3+, Cu1/2+, and Mn2+) to survive. However, as these are environmentally scarce, organisms have evolved sophisticated metal uptake machineries. In bacteria, high-affinity import of transition metals is predominantly mediated by ABC transporters. During bacterial infection, sequestration of metal by the host further limits the availability of these ions, and accordingly, bacterial ABC transporters (importers) of metals are key virulence determinants. However, the structure–function relationships of these metal transporters have not been fully elucidated. Here, we used metal-sensitivity assays, advanced structural modeling, and enzymatic assays to study the ABC transporter MntBC-A, a virulence determinant of the bacterial human pathogen Bacillus anthracis. We find that despite its broad metal-recognition profile, MntBC-A imports only manganese, whereas zinc can function as a high-affinity inhibitor of MntBC-A. Computational analysis shows that the transmembrane metal permeation pathway is lined with six titratable residues that can coordinate the positively charged metal, and mutagenesis studies show that they are essential for manganese transport. Modeling suggests that access to these titratable residues is blocked by a ladder of hydrophobic residues, and ATP-driven conformational changes open and close this hydrophobic seal to permit metal binding and release. The conservation of this arrangement of titratable and hydrophobic residues among ABC transporters of transition metals suggests a common mechanism. These findings advance our understanding of transmembrane metal recognition and permeation and may aid the design and development of novel antibacterial agents.
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Affiliation(s)
- Anastasiya Kuznetsova
- Department of Molecular Microbiology and the Rappaport Institute for Medical Sciences, Faculty of Medicine, The Technion-Israel Institute of Technology, Haifa, Israel
| | - Gal Masrati
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Elena Vigonsky
- Department of Molecular Microbiology and the Rappaport Institute for Medical Sciences, Faculty of Medicine, The Technion-Israel Institute of Technology, Haifa, Israel
| | - Nurit Livnat-Levanon
- Department of Molecular Microbiology and the Rappaport Institute for Medical Sciences, Faculty of Medicine, The Technion-Israel Institute of Technology, Haifa, Israel
| | - Jessica Rose
- Department of Molecular Microbiology and the Rappaport Institute for Medical Sciences, Faculty of Medicine, The Technion-Israel Institute of Technology, Haifa, Israel
| | - Moti Grupper
- Infectious Disease Unit, Rambam Health Care Campus, Haifa, Israel
| | - Adan Baloum
- Department of Molecular Microbiology and the Rappaport Institute for Medical Sciences, Faculty of Medicine, The Technion-Israel Institute of Technology, Haifa, Israel
| | - Janet G Yang
- Department of Chemistry, University of San Francisco, San Francisco, California, USA
| | - Douglas C Rees
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, California, USA
| | - Nir Ben-Tal
- Department of Biochemistry and Molecular Biology, George S. Wise Faculty of Life Sciences, Tel Aviv University, Tel Aviv, Israel
| | - Oded Lewinson
- Department of Molecular Microbiology and the Rappaport Institute for Medical Sciences, Faculty of Medicine, The Technion-Israel Institute of Technology, Haifa, Israel.
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Sharaf NG, Shahgholi M, Kim E, Lai JY, VanderVelde DG, Lee AT, Rees DC. Characterization of the ABC methionine transporter from Neisseria meningitidis reveals that lipidated MetQ is required for interaction. eLife 2021; 10:69742. [PMID: 34409939 PMCID: PMC8416018 DOI: 10.7554/elife.69742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2021] [Accepted: 08/18/2021] [Indexed: 01/05/2023] Open
Abstract
NmMetQ is a substrate-binding protein (SBP) from Neisseria meningitidis that has been identified as a surface-exposed candidate antigen for meningococcal vaccines. However, this location for NmMetQ challenges the prevailing view that SBPs in Gram-negative bacteria are localized to the periplasmic space to promote interaction with their cognate ABC transporter embedded in the bacterial inner membrane. To elucidate the roles of NmMetQ, we characterized NmMetQ with and without its cognate ABC transporter (NmMetNI). Here, we show that NmMetQ is a lipoprotein (lipo-NmMetQ) that binds multiple methionine analogs and stimulates the ATPase activity of NmMetNI. Using single-particle electron cryo-microscopy, we determined the structures of NmMetNI in the presence and absence of lipo-NmMetQ. Based on our data, we propose that NmMetQ tethers to membranes via a lipid anchor and has dual function and localization, playing a role in NmMetNI-mediated transport at the inner membrane and moonlighting on the bacterial surface.
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Affiliation(s)
- Naima G Sharaf
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States.,Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
| | - Mona Shahgholi
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States
| | - Esther Kim
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States
| | - Jeffrey Y Lai
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States.,Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
| | - David G VanderVelde
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States
| | - Allen T Lee
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States.,Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
| | - Douglas C Rees
- Division of Chemistry and Chemical Engineering, California Institute of Technology, Pasadena, United States.,Howard Hughes Medical Institute, California Institute of Technology, Pasadena, United States
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Zhou Y, Imlay JA. Escherichia coli K-12 Lacks a High-Affinity Assimilatory Cysteine Importer. mBio 2020; 11:e01073-20. [PMID: 32518189 PMCID: PMC7373191 DOI: 10.1128/mbio.01073-20] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2020] [Accepted: 05/05/2020] [Indexed: 01/09/2023] Open
Abstract
The most direct route by which microbes might assimilate sulfur would be by importing cysteine. However, alone among the amino acids, cysteine does not have well-characterized importers. We determined that Escherichia coli can rapidly import cysteine, but in our experiments, it did so primarily through the LIV ATP-driven system that is dedicated to branched-chain amino acids. The affinity of this system for cysteine is far lower than for Leu, Ile, and Val, and so in their presence, cysteine is excluded. Thus, this transport is unlikely to be relevant in natural environments. Growth studies, transcriptomics, and transport assays failed to detect any high-affinity importer that is dedicated to cysteine assimilation. Enteric bacteria do not contain the putative cysteine importer that was identified in Campylobacter jejuni This situation is surprising, because E. coli deploys ion- and/or ATP-driven transporters that import cystine, the oxidized form of cysteine, with high affinity and specificity. We conjecture that in oxic environments, molecular oxygen oxidizes environmental cysteine to cystine, which E. coli imports. In anoxic environments where cysteine is stable, the cell chooses to assimilate hydrogen sulfide instead. Calculations suggest that this alternative is almost as economical, and it avoids the toxic effects that can result when excess cysteine enters the cell.IMPORTANCE This investigation discovered that Escherichia coli lacks a transporter dedicated to the assimilation of cysteine, an outcome that is in striking contrast to the many transporters devoted to the other 19 amino acids. We ascribe the lack of a high-affinity cysteine importer to two considerations. First, the chemical reactivity of this amino acid is unique, and its poorly controlled import can have adverse consequences for the cell. Second, our analysis suggests that the economics of biosynthesis depend sharply upon whether the cell is respiring or fermenting. In the anoxic habitats in which cysteine might be found, the value of import versus biosynthesis is strongly reduced compared to that in oxic habitats. These studies may explain why bacteria choose to synthesize rather than to import other useful biomolecules as well.
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Affiliation(s)
- Yidan Zhou
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
| | - James A Imlay
- Department of Microbiology, University of Illinois, Urbana, Illinois, USA
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