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Chakchouk-Mtibaa A, Mechri S, Cheffi Azabou M, Triki MA, Smaoui S, Mellouli L. The novel bacteriocin BacYB1 produced by Leuconostoc mesenteroides YB1: From recent analytical characterization to biocontrol Verticillium dahliae and Agrobacterium tumefaciens. Microb Pathog 2024; 192:106680. [PMID: 38729380 DOI: 10.1016/j.micpath.2024.106680] [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: 03/13/2024] [Revised: 04/29/2024] [Accepted: 05/05/2024] [Indexed: 05/12/2024]
Abstract
Biocontrol of phytopathogens involving the use of bioactive compounds produced by lactic acid bacteria (LAB), is a promising approach to manage many diseases in agriculture. In this study, a lactic acid bacterium designated YB1 was isolated from fermented olives and selected for its antagonistic activity against Verticillium dahliae (V. dahliae) and Agrobacterium tumefaciens (A. tumefaciens). Based on the 16S rRNA gene nucleotide sequence analysis (1565 pb, accession number: OR714267), the new isolate YB1 bacterium was assigned as Leuconostoc mesenteroides YB1 (OR714267) strain. This bacterium produces an active peptide "bacteriocin" called BacYB1, which was purified in four steps. Matrix-assisted lasers desorption/ionization (MALDI) time-of-flight (TOF) mass spectrometry (MS) based approach was performed to identify and characterize BacYB1. The exact mass was 5470.75 Da, and the analysis of the N-terminal sequence (VTRASGASTPPGTASPFKTL) of BacYB1 revealed no significant similarity to currently available antimicrobial peptides. The BacYB1 displayed a bactericidal mode of action against A. tumefaciens. The potentiel role of BacYB1 to supress the growth of A. tumefaciens was confirmed by live-dead cells viability assay. In pot experiments, the biocontrol efficacy of BacYB1 against V. dahliae wilt on young olive trees was studied. The percentage of dead plants (PDP) and the final mean symptomes severity (FMS) of plants articifialy infected by V. dahliae and treated with the pre-purified peptide BacYB1 (preventive and curative treatments) were significantly inferior to untreated plants. Biochemical analysis of leaves of the plants has shown that polyophenols contents were highly detected in plants infected by V. dahliae and the highest contents of chlorophyl a, b and total chlorophyll were recorded in plants treated with the combination of BacYB1 with the biofertilisant Humivital. BacYB1 presents a promising alternative for the control of Verticillium wilt and crown gall diseases.
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Affiliation(s)
- Ahlem Chakchouk-Mtibaa
- Laboratory of Microbial and Enzymes Biotechnology and Biomolecules (LMEBB), Centre of Biotechnology of Sfax (CBS), University of Sfax-Tunisia, Road of Sidi Mansour Km 6, P. O. Box 1177, 3018, Sfax, Tunisia.
| | - Sondes Mechri
- Laboratory of Microbial and Enzymes Biotechnology and Biomolecules (LMEBB), Centre of Biotechnology of Sfax (CBS), University of Sfax-Tunisia, Road of Sidi Mansour Km 6, P. O. Box 1177, 3018, Sfax, Tunisia.
| | - Manel Cheffi Azabou
- Laboratory of Improvement and Protection of Olive Tree Genetic Resources, Olive Tree Institute, University of Sfax, Sfax, 3038, Tunisia.
| | - Mohamed Ali Triki
- Laboratory of Improvement and Protection of Olive Tree Genetic Resources, Olive Tree Institute, University of Sfax, Sfax, 3038, Tunisia.
| | - Slim Smaoui
- Laboratory of Microbial and Enzymes Biotechnology and Biomolecules (LMEBB), Centre of Biotechnology of Sfax (CBS), University of Sfax-Tunisia, Road of Sidi Mansour Km 6, P. O. Box 1177, 3018, Sfax, Tunisia.
| | - Lotfi Mellouli
- Laboratory of Microbial and Enzymes Biotechnology and Biomolecules (LMEBB), Centre of Biotechnology of Sfax (CBS), University of Sfax-Tunisia, Road of Sidi Mansour Km 6, P. O. Box 1177, 3018, Sfax, Tunisia.
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Pradhan P, Taviti AC, Beuria TK. The bacterial division protein MinDE has an independent function in flagellation. J Biol Chem 2024; 300:107117. [PMID: 38403244 PMCID: PMC10963238 DOI: 10.1016/j.jbc.2024.107117] [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: 01/11/2024] [Revised: 02/14/2024] [Accepted: 02/18/2024] [Indexed: 02/27/2024] Open
Abstract
Before preparing for division, bacteria stop their motility. During the exponential growth phase in Escherichia coli, when the rate of bacterial division is highest, the expression of flagellar genes is repressed and bacterial adhesion is enhanced. Hence, it is evident that cell division and motility in bacteria are linked; however, the specific molecular mechanism by which these two processes are linked is not known. While observing E. coli, we found that compared to the WT, the E. coli (Δmin) cells show higher motility and flagellation. We demonstrated that the higher motility was due to the absence of the Min system and can be restored to normal in the presence of Min proteins, where Min system negatively regulates flagella formation. The Min system in E. coli is widely studied for its role in the inhibition of polar Z-ring formation through its pole-to-pole oscillation. However, its role in bacterial motility is not explored. MinD homologs, FlhG and FleN, are known to control flagellar expression through their interaction with FlrA and FleQ, respectively. AtoC, a part of the two-component system AtoSC complex, is homologous to FlrA/FleQ, and the complex is involved in E. coli flagellation via its interaction with the fliA promoter. We have shown that MinD interacts directly with the AtoS of AtoSC complex and controls the fliA expression. Our findings suggest that the Min system acts as a link between cell division and motility in E. coli.
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Affiliation(s)
- Pinkilata Pradhan
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India; Regional Centre for Biotechnology, Faridabad, Haryana, India
| | - Ashoka Chary Taviti
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India
| | - Tushar Kant Beuria
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, Odisha, India.
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Guru A, Taviti AC, Sethy M, Ray S, Dixit A, Beuria TK. The cell division protein ZapE is targeted by the antibiotic aztreonam to induce cell filamentation in Escherichia coli. FEBS Lett 2023; 597:2931-2945. [PMID: 37857499 DOI: 10.1002/1873-3468.14759] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/23/2023] [Revised: 09/26/2023] [Accepted: 09/26/2023] [Indexed: 10/21/2023]
Abstract
Bacterial division is mediated by a protein complex called the Z-ring, and Z-ring associated protein E (ZapE) is a Z-ring-associated protein that acts as its negative regulator. In the present study, we show that treatment of Escherichia coli with the antibiotic aztreonam stabilized the Z-ring, induced filamentation, and reduced viability, with similar phenotypes being observed in ZapE deletion strains. Aztreonam treatment decreased ZapE expression, and the overexpression of ZapE rescued filamentous morphology significantly and viability partially. However, overexpression of filamentous temperature sensitive I (FtsI), a known target of aztreonam, could not rescue the filamentation. Interestingly, overexpression of ZapE and FtsI together was able to rescue both filamentous morphology and cell viability. Using in silico and biochemical analyses, we show that aztreonam directly interacts with ZapE. Our study suggests that the inhibitory effects of aztreonam in E. coli could be mediated by targeting ZapE.
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Affiliation(s)
- Ankeeta Guru
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
- Regional Centre for Biotechnology, Faridabad, India
| | | | - Madhusmita Sethy
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Srusti Ray
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
- Regional Centre for Biotechnology, Faridabad, India
| | - Anshuman Dixit
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
| | - Tushar Kant Beuria
- Infectious Disease Biology, Institute of Life Sciences, Bhubaneswar, India
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Zeng X, Hu L, Ai Q, Liu CJ, Xiong LX, Yang WW, Zhang X, Liu L, Li GQ. Helicobacter macacae MazF interplays with Escherichia coli homologs and enhances antibiotic tolerance. Helicobacter 2023; 28:e13014. [PMID: 37559199 DOI: 10.1111/hel.13014] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 05/15/2023] [Revised: 07/17/2023] [Accepted: 07/31/2023] [Indexed: 08/11/2023]
Abstract
BACKGROUND Toxin-antitoxin systems are highly variable, even among strains of the same bacterial species. The MazEF toxin-antitoxin system is found in many bacteria and plays important roles in various biological processes such as antibiotic tolerance and phage defense. However, no interplay of MazEF systems between different species was reported. MATERIALS AND METHODS MazEF toxin-antitoxin system of Helicobacter macacae was examined in three Escherichia coli strains with and without endogenous MazEF knockout. In vivo toxicity, antibiotic tolerance, and live/dead staining followed by flowcytometry analysis were performed to evaluate the functionality and interplay of the toxin-antitoxin system between the two species. RESULTS Controlled ectopic expression of MazF of H. macacae (MazFhm) in E. coli did not affect its growth. However, in endogenous MazEF knockout E. coli strains, MazFhm expression caused a sharp growth arrest. The toxicity of MazFhm could be neutralized by both the antitoxin of MazE homolog of H.macacae and the antitoxin of MazE of E. coli, indicating interplay of MazEF toxin-antitoxin systems between the two species. Induced expression of MazFhm enhanced tolerance to a lethal dose of levofloxacin, suggesting enhanced persister formation, which was further confirmed by live/dead cell staining. CONCLUSIONS The MazEF toxin-antitoxin system of H. macace enhances persister formation and thus antibiotic tolerance in E. coli. Our findings reveal an interplay between the MazEF systems of H. macacae and E. coli, emphasizing the need to consider this interaction while evaluating the toxicity and functionality of MazF homologs from different species in future studies.
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Affiliation(s)
- Xi Zeng
- Department of Gastroenterology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
- Department of Gastroenterology, The First Affiliated Hospital of Shaoyang University, Shaoyang, China
| | - Limiao Hu
- Department of Gastroenterology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
| | - Qi Ai
- Department of Gastroenterology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
| | - Cai-Juan Liu
- Department of Gastroenterology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
| | - Lu-Xi Xiong
- Department of Gastroenterology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
| | - Wei-Wei Yang
- Department of Gastroenterology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
| | - Xiaotuan Zhang
- Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University, Wenzhou, China
| | - Logen Liu
- Clinical Research Center, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
- Hunan Provincial Key Laboratory of Basic and Clinical Pharmacological Research on Gastrointestinal Tumors, University of South China, Hengyang, China
| | - Guo-Qing Li
- Department of Gastroenterology, The Second Affiliated Hospital, Hengyang Medical School, University of South China, Hengyang, China
- Hunan Provincial Key Laboratory of Basic and Clinical Pharmacological Research on Gastrointestinal Tumors, University of South China, Hengyang, China
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Liu X, Wang P, Shi Y, Cui Y, Li S, Wu Dong G, Li J, Hao M, Zhai Y, Zhou D, Liu W, Wang A, Jin Y. (P)ppGpp synthetase Rsh participates in rifampicin tolerance of persister cells in Brucella abortus in vitro. Microb Pathog 2023; 183:106310. [PMID: 37604214 DOI: 10.1016/j.micpath.2023.106310] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/28/2023] [Revised: 07/30/2023] [Accepted: 08/14/2023] [Indexed: 08/23/2023]
Abstract
Brucella abortus is facultative intracellular pathogen that causes chronic persistent infections and results in abortion and infertility in food animals. Recurrent infections can be one of the results of persister cells formation that transiently displays phenotypic tolerance to high dose of antibiotics treatment. We examined persister cells formation of B. abortus strain A19 in stationary phase and investigated a potential role for the (p)ppGpp synthetase Rsh in this process. We found that B. abortus stationary phase cells can produce higher levels of multi-drugs tolerant persister cells in vitro under high dose of antibiotics (20 × MIC) exposure than do exponential phase cells. Persister cell formation was also induced with environmental stressors pH 4.5, 0.01 M PBS (pH7.0), 2% NaCl and 25 °C, upon exposure to ampicillin, enrofloxacin and rifampicin. Persister cells were not formed following exposure to 1 mM H2O2. The numbers of persister cells were significantly increased following uptake of B. abortus stationary phase cells by RAW264.7 macrophages in contrast with cultures in TSB liquid medium. Environmental stressors to B. abortus significantly increased expression of rsh mRNA level. The rsh null mutant (Δrsh) formed significantly fewer persister cells than the complemented (CΔrsh) and wildtype (WT) strains under high dose of rifampicin in vitro. These data for the first time demonstrate that B. abortus can produce multi-drug tolerant persister cells in stationary phase. The (p)ppGpp synthetase Rsh is necessary for persister cell formation in B. abortus in the presence of rifampicin. On this basis, a new understanding of the recurrent infections of Brucella was advanced, thus provided a new basis for revelation of pathogenic mechanism of the chronic persistent infection in Brucella.
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Affiliation(s)
- Xiaofang Liu
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Pingping Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Yong Shi
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Yimeng Cui
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Shengnan Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Gaowa Wu Dong
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Junmei Li
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Mingyue Hao
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Yunyi Zhai
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Dong Zhou
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Wei Liu
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
| | - Aihua Wang
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China.
| | - Yaping Jin
- College of Veterinary Medicine, Northwest A&F University, Yangling, Shaanxi 712100, China; Key Laboratory of Animal Biotechnology of the Ministry of Agriculture, Northwest A&F University; Yangling, Shaanxi 712100, China
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Bu F, Liu M, Xie Z, Chen X, Li G, Wang X. Targeted Anti-Biofilm Therapy: Dissecting Targets in the Biofilm Life Cycle. Pharmaceuticals (Basel) 2022; 15:1253. [PMID: 36297365 PMCID: PMC9611117 DOI: 10.3390/ph15101253] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/18/2022] [Revised: 10/03/2022] [Accepted: 10/05/2022] [Indexed: 06/13/2024] Open
Abstract
Biofilm is a crucial virulence factor for microorganisms that causes chronic infection. After biofilm formation, the bacteria present improve drug tolerance and multifactorial defense mechanisms, which impose significant challenges for the use of antimicrobials. This indicates the urgent need for new targeted technologies and emerging therapeutic strategies. In this review, we focus on the current biofilm-targeting strategies and those under development, including targeting persistent cells, quorum quenching, and phage therapy. We emphasize biofilm-targeting technologies that are supported by blocking the biofilm life cycle, providing a theoretical basis for design of targeting technology that disrupts the biofilm and promotes practical application of antibacterial materials.
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Affiliation(s)
| | | | | | | | | | - Xing Wang
- State Key Laboratory of Organic-Inorganic Composites, Beijing Laboratory of Biomedical Materials, Beijing Advanced Innovation Center for Soft Matter Science and Engineering, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing 100029, China
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MBZM-N-IBT, a Novel Small Molecule, Restricts Chikungunya Virus Infection by Targeting nsP2 Protease Activity In Vitro, In Vivo, and Ex Vivo. Antimicrob Agents Chemother 2022; 66:e0046322. [PMID: 35766508 PMCID: PMC9295557 DOI: 10.1128/aac.00463-22] [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] [Indexed: 11/20/2022] Open
Abstract
The increase in disease incidences and persistent Chikungunya virus (CHIKV)-induced arthritis have been a huge burden on public health globally. In the absence of specific antivirals or vaccines, it is essential to continue efforts to develop effective anti-CHIKV strategies. Our previous study showing the in vitro anti-CHIKV potential of a novel molecule 1-[(2-methylbenzimidazol-1-yl) methyl]-2-oxo-indolin-3-ylidene] amino] thiourea (MBZM-N-IBT) encouraged us to further validate its efficacy. Here, the effect of MBZM-N-IBT was evaluated in vitro in RAW 264.7 cells, in vivo in C57BL/6 mice, and ex vivo in human peripheral blood mononuclear cells (hPBMCs). The study demonstrated that CHIKV infection was efficiently abrogated in RAW 264.7 cells (IC50 = 22.34 μM) with significant inhibition in viral proteins. The inhibition was effective in the postentry step, and MBZM-N-IBT predominately interfered in the early stages of CHIKV life cycle. It was further supported when the protease activity of CHIKV-nsP2 was hindered by the compound. Moreover, it diminished the CHIKV-induced inflammatory responses in vitro through significant downregulation of all the major mitogen-activated protein kinases (MAPKs), NF-κB, cyclooxygenase (COX)-2, and cytokines. Furthermore, MBZM-N-IBT restricted CHIKV infection and inflammation in vivo, leading to reduced clinical scores and complete survival of C57BL/6 mice. Additionally, it has been noticed that the CHIKV infection was reduced remarkably in hPBMC-derived monocyte-macrophage populations ex vivo by the compound. In conclusion, it can be suggested that this novel compound MBZM-N-IBT has been demonstrated to be a potential anti-CHIKV molecule in vitro, in vivo, and ex vivo and fulfilled all the criteria to investigate further for successful treatment of CHIKV infection.
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Ju Y, An Q, Zhang Y, Sun K, Bai L, Luo Y. Recent advances in Clp protease modulation to address virulence, resistance and persistence of MRSA infection. Drug Discov Today 2021; 26:2190-2197. [PMID: 34048895 DOI: 10.1016/j.drudis.2021.05.014] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/20/2021] [Revised: 04/17/2021] [Accepted: 05/20/2021] [Indexed: 02/05/2023]
Abstract
The Clp protease is an AAA+ protease that executes abnormally folded or malfunctioning proteins, and has an important role in producing virulence factors, forming biofilms or persisters and developing methicillin-resistant Staphylococcus aureus (MRSA). Recent studies showed that Clp protease controls virulence via agr signaling and degrades antitoxins of the toxin-antitoxin system to modulate the formation of persisters and biofilms. In this review, we focus on recent developments concerning the virulence and persistence regulatory pathways and resistance-related mechanism of Clp protease in S. aureus, with an overview of the Clp modulators developed to treat MRSA infection.
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Affiliation(s)
- Yuan Ju
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China; Sichuan University Library, Sichuan University, Chengdu 610041, China
| | - Qi An
- Public Health Clinical Center of Chengdu, Chengdu 610041, China
| | - Yiwen Zhang
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Ke Sun
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China
| | - Lang Bai
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China.
| | - Youfu Luo
- Center of Infectious Diseases and State Key Laboratory of Biotherapy, West China Hospital, West China Medical School, Sichuan University, Chengdu 610041, China.
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