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Lamichhane B, Mawad AMM, Saleh M, Kelley WG, Harrington PJ, Lovestad CW, Amezcua J, Sarhan MM, El Zowalaty ME, Ramadan H, Morgan M, Helmy YA. Salmonellosis: An Overview of Epidemiology, Pathogenesis, and Innovative Approaches to Mitigate the Antimicrobial Resistant Infections. Antibiotics (Basel) 2024; 13:76. [PMID: 38247636 PMCID: PMC10812683 DOI: 10.3390/antibiotics13010076] [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: 11/21/2023] [Revised: 12/24/2023] [Accepted: 01/10/2024] [Indexed: 01/23/2024] Open
Abstract
Salmonella is a major foodborne pathogen and a leading cause of gastroenteritis in humans and animals. Salmonella is highly pathogenic and encompasses more than 2600 characterized serovars. The transmission of Salmonella to humans occurs through the farm-to-fork continuum and is commonly linked to the consumption of animal-derived food products. Among these sources, poultry and poultry products are primary contributors, followed by beef, pork, fish, and non-animal-derived food such as fruits and vegetables. While antibiotics constitute the primary treatment for salmonellosis, the emergence of antibiotic resistance and the rise of multidrug-resistant (MDR) Salmonella strains have highlighted the urgency of developing antibiotic alternatives. Effective infection management necessitates a comprehensive understanding of the pathogen's epidemiology and transmission dynamics. Therefore, this comprehensive review focuses on the epidemiology, sources of infection, risk factors, transmission dynamics, and the host range of Salmonella serotypes. This review also investigates the disease characteristics observed in both humans and animals, antibiotic resistance, pathogenesis, and potential strategies for treatment and control of salmonellosis, emphasizing the most recent antibiotic-alternative approaches for infection control.
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Affiliation(s)
- Bibek Lamichhane
- Department of Veterinary Science, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - Asmaa M. M. Mawad
- Botany and Microbiology Department, Faculty of Science, Assiut University, Assiut 71516, Egypt
| | - Mohamed Saleh
- Department of Veterinary Science, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - William G. Kelley
- Department of Veterinary Science, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - Patrick J. Harrington
- Department of Veterinary Science, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - Cayenne W. Lovestad
- Department of Veterinary Science, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - Jessica Amezcua
- Department of Veterinary Science, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - Mohamed M. Sarhan
- Faculty of Pharmacy, King Salman International University (KSIU), Ras Sudr 8744304, Egypt
| | - Mohamed E. El Zowalaty
- Veterinary Medicine and Food Security Research Group, Medical Laboratory Sciences Program, Faculty of Health Sciences, Abu Dhabi Women’s Campus, Higher Colleges of Technology, Abu Dhabi 41012, United Arab Emirates
| | - Hazem Ramadan
- Hygiene and Zoonoses Department, Faculty of Veterinary Medicine, Mansoura University, Mansoura 35516, Egypt
| | - Melissa Morgan
- Department of Animal and Food Sciences, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
| | - Yosra A. Helmy
- Department of Veterinary Science, Martin-Gatton College of Agriculture, Food and Environment, University of Kentucky, Lexington, KY 40546, USA
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2
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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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Parga A, Muras A, Otero-Casal P, Arredondo A, Soler-Ollé A, Àlvarez G, Alcaraz LD, Mira A, Blanc V, Otero A. The quorum quenching enzyme Aii20J modifies in vitro periodontal biofilm formation. Front Cell Infect Microbiol 2023; 13:1118630. [PMID: 36816581 PMCID: PMC9932050 DOI: 10.3389/fcimb.2023.1118630] [Citation(s) in RCA: 14] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2022] [Accepted: 01/20/2023] [Indexed: 02/05/2023] Open
Abstract
Introduction Recent studies have revealed the presence of N-acyl-homoserine lactones (AHLs) quorum sensing (QS) signals in the oral environment. Yet, their role in oral biofilm development remains scarcely investigated. The use of quorum quenching (QQ) strategies targeting AHLs has been described as efficient for the control of pathogenic biofilms. Here, we evaluate the use of a highly active AHL-targeting QQ enzyme, Aii20J, to modulate oral biofilm formation in vitro. Methods The effect of the QQ enzyme was studied in in vitro multispecies biofilms generated from oral samples taken from healthy donors and patients with periodontal disease. Subgingival samples were used as inocula, aiming to select members of the microbiota of the periodontal pocket niche in the in vitro biofilms. Biofilm formation abilities and microbial composition were studied upon treating the biofilms with the QQ enzyme Aii20J. Results and Discussion The addition of the enzyme resulted in significant biofilm mass reductions in 30 - 60% of the subgingival-derived biofilms, although standard AHLs could not be found in the supernatants of the cultured biofilms. Changes in biofilm mass were not accompanied by significant alterations of bacterial relative abundance at the genus level. The investigation of 125 oral supragingival metagenomes and a synthetic subgingival metagenome revealed a surprisingly high abundance and broad distribution of homologous of the AHL synthase HdtS and several protein families of AHL receptors, as well as an enormous presence of QQ enzymes, pointing to the existence of an intricate signaling network in oral biofilms that has been so far unreported, and should be further investigated. Together, our findings support the use of Aii20J to modulate polymicrobial biofilm formation without changing the microbiome structure of the biofilm. Results in this study suggest that AHLs or AHL-like molecules affect oral biofilm formation, encouraging the application of QQ strategies for oral health improvement, and reinforcing the importance of personalized approaches to oral biofilm control.
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Affiliation(s)
- Ana Parga
- Department of Microbiology and Parasitology, CIBUS-Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Andrea Muras
- Department of Microbiology and Parasitology, CIBUS-Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
| | - Paz Otero-Casal
- Department of Surgery and Medical-Surgical Specialties, Faculty of Medicine and Odontology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
- Unit of Oral Health, Santa Comba-Negreira, (CS) SERGAS, Santiago de Compostela, Spain
| | - Alexandre Arredondo
- Department of Microbiology, Dentaid Research Center, Cerdanyola Del Vallès, Spain
| | - Agnès Soler-Ollé
- Department of Microbiology, Dentaid Research Center, Cerdanyola Del Vallès, Spain
| | - Gerard Àlvarez
- Department of Microbiology, Dentaid Research Center, Cerdanyola Del Vallès, Spain
| | - Luis D. Alcaraz
- Department of Cellular Biology, Faculty of Sciences, National Autonomous University of Mexico, Coyoacán, Mexico
| | - Alex Mira
- Department of Genomics and Health, FISABIO Foundation, Valencia, Spain
| | - Vanessa Blanc
- Department of Microbiology, Dentaid Research Center, Cerdanyola Del Vallès, Spain
| | - Ana Otero
- Department of Microbiology and Parasitology, CIBUS-Faculty of Biology, Universidade de Santiago de Compostela, Santiago de Compostela, Spain
- *Correspondence: Ana Otero,
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Styles MJ, Boursier ME, McEwan MA, Santa EE, Mattmann ME, Slinger BL, Blackwell HE. Autoinducer-fluorophore conjugates enable FRET in LuxR proteins in vitro and in cells. Nat Chem Biol 2022; 18:1115-1124. [PMID: 35927585 PMCID: PMC9529866 DOI: 10.1038/s41589-022-01089-1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Accepted: 06/21/2022] [Indexed: 11/09/2022]
Abstract
Cell-to-cell signaling, or quorum sensing (QS), in many Gram-negative bacteria is governed by small molecule signals (N-acyl-L-homoserine lactones, AHLs) and their cognate receptors (LuxR-type proteins). The mechanistic underpinnings of QS in these bacteria are severely limited due to the challenges of isolating and manipulating most LuxR-type proteins. Reports of quantitative direct-binding experiments on LuxR-type proteins are scarce, and robust and generalizable methods that provide such data are largely nonexistent. We report herein a Förster resonance energy transfer (FRET) assay that leverages (1) conserved tryptophans located in the LuxR-type protein ligand-binding site and synthetic fluorophore-AHL conjugates, and (2) isolation of the proteins bound to weak agonists. The FRET assay permits straightforward measurement of ligand-binding affinities with receptor-either in vitro or in cells-and was shown to be compatible with six LuxR-type proteins. These methods will advance fundamental investigations of LuxR-type protein mechanism and the development of small molecule QS modulators.
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Affiliation(s)
- Matthew J Styles
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | | | | | - Emma E Santa
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | | | - Betty L Slinger
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA
| | - Helen E Blackwell
- Department of Chemistry, University of Wisconsin-Madison, Madison, WI, USA.
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Sionov RV, Steinberg D. Targeting the Holy Triangle of Quorum Sensing, Biofilm Formation, and Antibiotic Resistance in Pathogenic Bacteria. Microorganisms 2022; 10:1239. [PMID: 35744757 PMCID: PMC9228545 DOI: 10.3390/microorganisms10061239] [Citation(s) in RCA: 43] [Impact Index Per Article: 21.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2022] [Revised: 06/12/2022] [Accepted: 06/14/2022] [Indexed: 12/12/2022] Open
Abstract
Chronic and recurrent bacterial infections are frequently associated with the formation of biofilms on biotic or abiotic materials that are composed of mono- or multi-species cultures of bacteria/fungi embedded in an extracellular matrix produced by the microorganisms. Biofilm formation is, among others, regulated by quorum sensing (QS) which is an interbacterial communication system usually composed of two-component systems (TCSs) of secreted autoinducer compounds that activate signal transduction pathways through interaction with their respective receptors. Embedded in the biofilms, the bacteria are protected from environmental stress stimuli, and they often show reduced responses to antibiotics, making it difficult to eradicate the bacterial infection. Besides reduced penetration of antibiotics through the intricate structure of the biofilms, the sessile biofilm-embedded bacteria show reduced metabolic activity making them intrinsically less sensitive to antibiotics. Moreover, they frequently express elevated levels of efflux pumps that extrude antibiotics, thereby reducing their intracellular levels. Some efflux pumps are involved in the secretion of QS compounds and biofilm-related materials, besides being important for removing toxic substances from the bacteria. Some efflux pump inhibitors (EPIs) have been shown to both prevent biofilm formation and sensitize the bacteria to antibiotics, suggesting a relationship between these processes. Additionally, QS inhibitors or quenchers may affect antibiotic susceptibility. Thus, targeting elements that regulate QS and biofilm formation might be a promising approach to combat antibiotic-resistant biofilm-related bacterial infections.
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Affiliation(s)
- Ronit Vogt Sionov
- The Biofilm Research Laboratory, The Institute of Biomedical and Oral Research, The Faculty of Dental Medicine, Hadassah Medical School, The Hebrew University, Jerusalem 9112102, Israel;
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Refactoring transcription factors for metabolic engineering. Biotechnol Adv 2022; 57:107935. [PMID: 35271945 DOI: 10.1016/j.biotechadv.2022.107935] [Citation(s) in RCA: 36] [Impact Index Per Article: 18.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2021] [Revised: 02/04/2022] [Accepted: 03/03/2022] [Indexed: 12/19/2022]
Abstract
Due to the ability to regulate target metabolic pathways globally and dynamically, metabolic regulation systems composed of transcription factors have been widely used in metabolic engineering and synthetic biology. This review introduced the categories, action principles, prediction strategies, and related databases of transcription factors. Then, the application of global transcription machinery engineering technology and the transcription factor-based biosensors and quorum sensing systems are overviewed. In addition, strategies for optimizing the transcriptional regulatory tools' performance by refactoring transcription factors are summarized. Finally, the current limitations and prospects of constructing various regulatory tools based on transcription factors are discussed. This review will provide theoretical guidance for the rational design and construction of transcription factor-based metabolic regulation systems.
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Styles MJ, Early SA, Tucholski T, West KHJ, Ge Y, Blackwell HE. Chemical Control of Quorum Sensing in E. coli: Identification of Small Molecule Modulators of SdiA and Mechanistic Characterization of a Covalent Inhibitor. ACS Infect Dis 2020; 6:3092-3103. [PMID: 33124430 DOI: 10.1021/acsinfecdis.0c00654] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/22/2022]
Abstract
Enterohemorrhagic Escherichia coli (EHEC) is the causative agent of severe diarrheal disease in humans. Cattle are the natural reservoir of EHEC, and approximately 75% of EHEC infections in humans stem from bovine products. Many common bacterial pathogens, including EHEC, rely on chemical communication systems, such as quorum sensing (QS), to regulate virulence and facilitate host colonization. EHEC uses SdiA from E. coli (SdiAEC), an orphan LuxR-type receptor, to sense N-acyl l-homoserine lactone (AHL) QS signals produced by other members of the bovine enteric microbiome. SdiAEC regulates two phenotypes critical for colonizing cattle: acid resistance and the formation of attaching and effacing lesions. Despite the importance of SdiAEC, there is very little known about its selectivity for different AHL signals, and no chemical inhibitors that act specifically on SdiAEC have been reported. Such compounds would represent valuable tools to study the roles of QS in EHEC virulence. To identify chemical modulators of SdiAEC and delineate the structure-activity relationships (SARs) for AHL activity in this receptor, we report herein the screening of a focused library composed largely of AHLs and AHL analogues in an SdiAEC reporter assay. We describe the identity and SARs of potent modulators of SdiAEC activity, examine the promiscuity of SdiAEC, characterize the mechanism of a covalent inhibitor, and provide phenotypic assay data to support that these compounds can control SdiAEC-dependent acid resistance in E. coli. These SdiAEC modulators could be used to advance the study of LuxR-type receptor/ligand interactions, the biological roles of orphan LuxR-type receptors, and potential QS-based therapeutic approaches.
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Affiliation(s)
- Matthew J. Styles
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Stephen A. Early
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Trisha Tucholski
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Korbin H. J. West
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Ying Ge
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
- Department of Cell and Regenerative Biology, Wisconsin Institute for Medical Research, University of Wisconsin−Madison, 1111 Highland Avenue, Madison, Wisconsin 53705, United States
| | - Helen E. Blackwell
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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Acharya D, Miller I, Cui Y, Braun DR, Berres ME, Styles MJ, Li L, Kwan J, Rajski SR, Blackwell HE, Bugni TS. Omics Technologies to Understand Activation of a Biosynthetic Gene Cluster in Micromonospora sp. WMMB235: Deciphering Keyicin Biosynthesis. ACS Chem Biol 2019; 14:1260-1270. [PMID: 31120241 PMCID: PMC6591704 DOI: 10.1021/acschembio.9b00223] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
![]()
DNA
sequencing of a large collection of bacterial genomes reveals
a wealth of orphan biosynthetic gene clusters (BGCs) with no identifiable
products. BGC silencing, for those orphan clusters that are truly
silent, rather than those whose products have simply evaded detection
and cluster correlation, is postulated to result from transcriptional
inactivation of these clusters under standard laboratory conditions.
Here, we employ a multi-omics approach to demonstrate how interspecies
interactions modulate the keyicin producing kyc cluster
at the transcriptome level in cocultures of kyc-bearing Micromonospora sp. and a Rhodococcus sp.
We further correlate coculture dependent changes in keyicin production
to changes in transcriptomic and proteomic profiles and show that
these changes are attributable to small molecule signaling consistent
with a quorum sensing pathway. In piecing together the various elements
underlying keyicin production in coculture, this study highlights
how omics technologies can expedite future efforts to understand and
exploit silent BGCs.
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Affiliation(s)
- Deepa Acharya
- Pharmaceutical Sciences Division, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Ian Miller
- Pharmaceutical Sciences Division, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Yusi Cui
- Pharmaceutical Sciences Division, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Doug R. Braun
- Pharmaceutical Sciences Division, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Mark E. Berres
- Bioinformatics Resource Center, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Matthew J. Styles
- Department of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Lingjun Li
- Pharmaceutical Sciences Division, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Jason Kwan
- Pharmaceutical Sciences Division, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Scott R. Rajski
- Pharmaceutical Sciences Division, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
| | - Helen E. Blackwell
- Department of Chemistry, University of Wisconsin—Madison, Madison, Wisconsin 53706, United States
| | - Tim S. Bugni
- Pharmaceutical Sciences Division, University of Wisconsin—Madison, Madison, Wisconsin 53705, United States
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Boursier ME, Combs JB, Blackwell HE. N-Acyl l-Homocysteine Thiolactones Are Potent and Stable Synthetic Modulators of the RhlR Quorum Sensing Receptor in Pseudomonas aeruginosa. ACS Chem Biol 2019; 14:186-191. [PMID: 30668907 DOI: 10.1021/acschembio.8b01079] [Citation(s) in RCA: 17] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The RhlR quorum sensing (QS) receptor in the pathogen Pseudomonas aeruginosa plays a prominent role in infection, and both antagonism and agonism of RhlR have been shown to negatively regulate important virulence phenotypes. Non-native lactone ligands are known to modulate RhlR activity, but their utility as chemical probes is relatively limited due to hydrolytic instability. Herein, we report our design and biological evaluation of a suite of hybrid AHL analogs with structures merging (1) features of reported lead RhlR ligands and (2) head groups with improved hydrolytic stabilities. The most promising compounds identified were N-acyl l-homocysteine thiolactones, which displayed enhanced stabilities relative to lactones. Moreover, they were highly selective for RhlR over another key QS receptor in P. aeruginosa, LasR. These compounds are among the most potent RhlR modulators known and represent robust chemical tools to dissect the complex roles of RhlR in the P. aeruginosa QS circuitry.
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Affiliation(s)
- Michelle E. Boursier
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Joshua B. Combs
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
| | - Helen E. Blackwell
- Department of Chemistry, University of Wisconsin−Madison, 1101 University Avenue, Madison, Wisconsin 53706, United States
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