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Tabassum N, Jeong GJ, Jo DM, Khan F, Kim YM. Attenuation of biofilm and virulence factors of Pseudomonas aeruginosa by tetramethylpyrazine-gold nanoparticles. Microb Pathog 2024; 191:106658. [PMID: 38643850 DOI: 10.1016/j.micpath.2024.106658] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2024] [Revised: 04/15/2024] [Accepted: 04/18/2024] [Indexed: 04/23/2024]
Abstract
Pseudomonas aeruginosa is often identified as the causative agent in nosocomial infections. Their adapted resistance makes them strong towards antimicrobial treatments. They protect and empower their survival behind strong biofilm architecture that works as their armor toward antimicrobial therapy. Additionally, P. aeruginosa generates virulence factors, contributing to chronic infection and recalcitrant phenotypic characteristics. The current study utilizes the benevolence of nanotechnology to develop an alternate technique to control the spreading of P. aeruginosa by limiting its biofilm and virulence development. This study used a natural compound, tetramethylpyrazine, to generate gold nanoparticles. Tetramethylpyrazine-gold nanoparticles (Tet-AuNPs) were presented in spherical shapes, with an average size of 168 ± 52.49 nm and a zeta potential of -12.22 ± 2.06 mV. The minimum inhibition concentration (MIC) of Tet-AuNPs that proved more than 90 % effective in inhibiting P. aeruginosa was 256 μg/mL. Additionally, it also shows antibacterial activities against Staphylococcus aureus (MIC, 256 μg/mL), Streptococcus mutans (MIC, 128 μg/mL), Klebsiella pneumoniae (MIC, 128 μg/mL), Listeria monocytogenes (MIC, 256 μg/mL), and Escherichia coli (MIC, 256 μg/mL). The sub-MIC values of Tet-AuNPs significantly inhibited the early-stage biofilm formation of P. aeruginosa. Moreover, this concentration strongly affected hemolysis, protease activity, and different forms of motilities in P. aeruginosa. Additionally, Tet-AuNPs destroyed the well-established mature biofilm of P. aeruginosa. The expression of genes linked with the biofilm formation and virulence in P. aeruginosa treated with sub-MIC doses of Tet-AuNPs was shown to be significantly suppressed. Gene expression studies support biofilm- and virulence-suppressing effects of Tet-AuNPs at the phenotypic level.
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Affiliation(s)
- Nazia Tabassum
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea; Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Geum-Jae Jeong
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea; Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Du-Min Jo
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea; National Marine Biodiversity Institute of Korea, Seochun, Chungcheongnam-do, 33662, Republic of Korea
| | - Fazlurrahman Khan
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea; Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Institute of Fisheries Science, Pukyong National University, Busan, 48513, Republic of Korea.
| | - Young-Mog Kim
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea; Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea.
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Oh D, Khan F, Park SK, Jo DM, Kim NG, Jung WK, Kim YM. Antimicrobial, antibiofilm, and antivirulence properties of Eisenia bicyclis-extracts and Eisenia bicyclis-gold nanoparticles towards microbial pathogens. Microb Pathog 2024; 188:106546. [PMID: 38278457 DOI: 10.1016/j.micpath.2024.106546] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2023] [Revised: 12/28/2023] [Accepted: 01/15/2024] [Indexed: 01/28/2024]
Abstract
Nanomaterials derived from seaweed have developed as an alternative option for fighting infections caused by biofilm-forming microbial pathogens. This research aimed to discover potential seaweed-derived nanomaterials with antimicrobial and antibiofilm action against bacterial and fungal pathogens. Among seven algal species, the extract from Eisenia bicyclis inhibited biofilms of Klebsiella pneumoniae, Staphylococcus aureus, and Listeria monocytogenes most effectively at sub-MIC levels. As a result, in the present study, E. bicyclis was chosen as a prospective seaweed for producing E. bicyclis-gold nanoparticles (EB-AuNPs). Furthermore, the mass spectra of E. bicyclis reveal the presence of a number of potentially beneficial chemicals. The polyhedral shape of the synthesized EB-AuNP with a size value of 154.74 ± 33.46 nm was extensively described. The lowest inhibitory concentration of EB-AuNPs against bacterial pathogens (e.g., L.monocytogenes, S. aureus, Pseudomonas aeruginosa, and K. pneumoniae) and fungal pathogens (Candida albicans) ranges from 512 to >2048 μg/mL. Sub-MIC of EB-AuNPs reduces biofilm formation in P. aeruginosa, K. pneumoniae, L. monocytogenes, and S. aureus by 57.22 %, 58.60 %, 33.80 %, and 91.13 %, respectively. EB-AuNPs eliminate the mature biofilm of K. pneumoniae at > MIC, MIC, and sub-MIC concentrations. Furthermore, EB-AuNPs at the sub-MIC level suppress key virulence factors generated by P. aeruginosa, including motility, protease activity, pyoverdine, and pyocyanin, whereas it also suppresses the production of staphyloxanthin virulence factor from S. aureus. The current research reveals that seaweed extracts and a biocompatible seaweed-AuNP have substantial antibacterial, antibiofilm, and antivirulence actions against bacterial and fungal pathogens.
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Affiliation(s)
- DoKyung Oh
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea; Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea
| | - Fazlurrahman Khan
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea; Institute of Fisheries Sciences, Pukyong National University, Busan, 48513, Republic of Korea
| | - Seul-Ki Park
- Smart Food Manufacturing Project Group, Korea Food Research Institute, Wanju, 55365, Republic of Korea
| | - Du-Min Jo
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea; Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea
| | - Nam-Gyun Kim
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Major of Biomedical Engineering, Division of Smart Healthcare, College of Information Technology and Convergence and New-Senior Healthcare Innovation Center (BK21 Plus), Pukyong National University, Busan, 48513, Republic of Korea
| | - Won-Kyo Jung
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea; Major of Biomedical Engineering, Division of Smart Healthcare, College of Information Technology and Convergence and New-Senior Healthcare Innovation Center (BK21 Plus), Pukyong National University, Busan, 48513, Republic of Korea
| | - Young-Mog Kim
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea; Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea; Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
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Tabassum N, Khan F, Jeong GJ, Oh D, Kim YM. Antibiofilm and antivirulence activities of laminarin-gold nanoparticles in standard and host-mimicking media. Appl Microbiol Biotechnol 2024; 108:203. [PMID: 38349556 PMCID: PMC10864539 DOI: 10.1007/s00253-024-13050-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/27/2023] [Revised: 01/02/2024] [Accepted: 02/05/2024] [Indexed: 02/15/2024]
Abstract
The rapidly rising antimicrobial resistance (AMR) in pathogenic bacteria has become one of the most serious public health challenges, with a high death rate. Most pathogenic bacteria have been recognized as a source of AMR and a primary barrier to antimicrobial treatment failure due to the development of biofilms and the production of virulence factors. In this work, nanotechnology was employed as a substitute method to control the formation of biofilms and attenuate virulence features in Pseudomonas aeruginosa and Staphylococcus aureus. We synthesized biocompatible gold nanoparticles from marine-derived laminarin as potential biofilm and virulence treatments. Laminarin-gold nanoparticles (Lam-AuNPs) have been identified as spherical, 49.84 ± 7.32 nm in size and - 26.49 ± 1.29 mV zeta potential. The MIC value of Lam-AuNPs against several drug-resistant microbial pathogens varied from 2 to 1024 μg/mL in both standard and host-mimicking media. Sub-MIC values of Lam-AuNPs were reported to effectively reduce the production of P. aeruginosa and S. aureus biofilms in both standard and host-mimicking growth media. Furthermore, the sub-MIC of Lam-AuNPs strongly reduced hemolysis, pyocyanin, pyoverdine, protease, and several forms of flagellar and pili-mediated motility in P. aeruginosa. Lam-AuNPs also inhibited S. aureus hemolysis and the production of amyloid fibrils. The Lam-AuNPs strongly dispersed the preformed mature biofilm of these pathogens in a dose-dependent manner. The Lam-AuNPs would be considered an alternative antibiofilm and antivirulence agent to control P. aeruginosa and S. aureus infections. KEY POINTS: • Lam-AuNPs were biosynthesized to control biofilm and virulence. • Lam-AuNPs show effective biofilm inhibition in standard and host-mimicking media. • Lam-AuNPs suppress various virulence factors of P. aeruginosa and S. aureus.
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Affiliation(s)
- Nazia Tabassum
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Fazlurrahman Khan
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
- Institute of Fisheries Sciences, Pukyong National University, Busan, 48513, Republic of Korea.
| | - Geum-Jae Jeong
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Dokyung Oh
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea
| | - Young-Mog Kim
- Marine Integrated Biomedical Technology Center, The National Key Research Institutes in Universities, Pukyong National University, Busan, 48513, Republic of Korea.
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan, 48513, Republic of Korea.
- Department of Food Science and Technology, Pukyong National University, Busan, 48513, Republic of Korea.
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Yalkut K, Ben Ali Hassine S, Basaran E, Kula C, Ozcan A, Avci FG, Keskin O, Sariyar Akbulut B, Ozbek P. Attenuation of Type IV pili activity by natural products. J Biomol Struct Dyn 2024:1-11. [PMID: 38305801 DOI: 10.1080/07391102.2024.2310781] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/08/2023] [Accepted: 01/20/2024] [Indexed: 02/03/2024]
Abstract
The virulence factor Type IV pili (T4P) are surface appendages used by the opportunistic pathogen Pseudomonas aeruginosa for twitching motility and adhesion in the environment and during infection. Additionally, the use of these appendages by P. aeruginosa for biofilm formation increases its virulence and drug resistance. Therefore, attenuation of the activity of T4P would be desirable to control P. aeruginosa infections. Here, a computational approach has been pursued to screen natural products that can be used for this purpose. PilB, the elongation ATPase of the T4P machinery in P. aeruginosa, has been selected as the target subunit and virtual screening of FDA-approved drugs has been conducted. Screening identified two natural compounds, ergoloid and irinotecan, as potential candidates for inhibiting this T4P-associated ATPase in P. aeruginosa. These candidate compounds underwent further rigorous evaluation through molecular dynamics (MD) simulations and then through in vitro twitching motility and biofilm inhibition assays. Notably, ergoloid emerged as a particularly promising candidate for weakening the T4P activity by inhibiting the elongation ATPases associated with T4P. This repurposing study paves the way for the timely discovery of antivirulence drugs as an alternative to classical antibiotic treatments to help combat infections caused by P. aeruginosa and related pathogens.Communicated by Ramaswamy H. Sarma.
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Affiliation(s)
- Kerem Yalkut
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Soumaya Ben Ali Hassine
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
- Department of Bioengineering, Faculty of Engineering and Natural Sciences, Uskudar University, Istanbul, Turkey
| | - Esra Basaran
- Graduate School of Sciences and Engineering, Koc University, Istanbul, Turkey
| | - Ceyda Kula
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Aslıhan Ozcan
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Fatma Gizem Avci
- Department of Bioengineering, Faculty of Engineering and Natural Sciences, Uskudar University, Istanbul, Turkey
| | - Ozlem Keskin
- Graduate School of Sciences and Engineering, Koc University, Istanbul, Turkey
| | - Berna Sariyar Akbulut
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
| | - Pemra Ozbek
- Department of Bioengineering, Faculty of Engineering, Marmara University, Istanbul, Turkey
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Gómez-Salgado MDRH, Beltrán-Gómez JÁ, Díaz-Nuñez JL, Rivera-Chávez JA, García-Contreras R, Estrada-Velasco ÁY, Quezada H, Serrano Bello CA, Castillo-Juárez I. Efficacy of a Mexican folk remedy containing cuachalalate (Amphipterygium adstringens (Schltdl.) Schiede ex Standl) for the treatment of burn wounds infected with Pseudomonas aeruginosa. J Ethnopharmacol 2024; 319:117305. [PMID: 37848078 DOI: 10.1016/j.jep.2023.117305] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Revised: 10/02/2023] [Accepted: 10/08/2023] [Indexed: 10/19/2023]
Abstract
ETHNOPHARMACOLOGICAL RELEVANCE Cuachalalate (Amphipterygium adstringens) stem bark has been used to heal wounds and counteract microbial infections since pre-Hispanic times. However, its effect in treating infected burns remains unclear. STUDY OBJECTIVES To determine the antipathogenic capacity of a folk remedy (FR) containing cuachalalate stem bark to treat lesions caused by thermal damage and bacterial infection. MATERIALS AND METHODS The antipathogenic capacity of the hexanic extract (HE) and FR was evaluated in a burned mouse model infected with Pseudomonas aeruginosa. Second to third-degree burns were induced with 95 °C water in CD1 mice in similar ratios of males to females. The mice were randomly grouped into non-inoculated (Group 1) and P. aeruginosa inoculated. The latter were divided into untreated infection (Group 2) and infection topically treated with HE (Group 3), silver sulfadiazine (Group 4), and tween 80 (Group 5). In the case of FR, the lesions were washed with an aqueous extract (AE) and applied powdered stem bark (Group 6). Animal survival, establishment of the bacteria in the lesions, and systemic dispersion were determined. In addition, histopathological analysis was performed. The chemical composition of the AE was analyzed through molecular networking analysis, and the antivirulence capacity was determined through the inhibition of pyocyanin production and caseinolytic activity. RESULTS Only the FR showed antipathogenic activity and increased animal survival by 50% by reducing the systemic dispersion of P. aeruginosa. In addition, it stimulated the formation of granulation tissue and the generation of new blood vessels. The AE did not show bactericidal activity but reduced bacterial virulence, and glycosylated flavonoids and catechins were identified as its main constituents. CONCLUSIONS The results of this study contribute to validating the effectiveness of a popular remedy containing cuachalalate stem bark for treating burns infected with P. aeruginosa.
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Affiliation(s)
| | - José Ángel Beltrán-Gómez
- Laboratorio de Investigación y Aplicación de Fitoquímicos Bioactivos, Posgrado en Botánica, Colegio de Postgraduados, Texcoco, 56230, Mexico.
| | - José Luis Díaz-Nuñez
- Laboratorio de Investigación y Aplicación de Fitoquímicos Bioactivos, Posgrado en Botánica, Colegio de Postgraduados, Texcoco, 56230, Mexico.
| | - José Alberto Rivera-Chávez
- Departamento de Productos Naturales, Instituto de Química, Universidad Nacional Autónoma de México, CDMX, Mexico.
| | - Rodolfo García-Contreras
- Departamento de Microbiología y Parasitología, Universidad Nacional Autónoma de México, Ciudad Universitaria, CDMX, 04510, Mexico.
| | - Ángel Yahir Estrada-Velasco
- Departamento de Microbiología y Parasitología, Universidad Nacional Autónoma de México, Ciudad Universitaria, CDMX, 04510, Mexico.
| | - Héctor Quezada
- Laboratorio de Investigación en Inmunología y Proteómica, Hospital Infantil de México Federico Gómez, CDMX, 06720, Mexico.
| | - Carlos Alberto Serrano Bello
- Departamento de Patología Clínica y Experimental, Hospital Infantil de México Federico Gómez, CDMX, 06720, Mexico.
| | - Israel Castillo-Juárez
- Laboratorio de Investigación y Aplicación de Fitoquímicos Bioactivos, Posgrado en Botánica, Colegio de Postgraduados, Texcoco, 56230, Mexico.
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Mirpour M, Zahmatkesh H. Ketoprofen attenuates Las/Rhl quorum-sensing (QS) systems of Pseudomonas aeruginosa: molecular and docking studies. Mol Biol Rep 2024; 51:133. [PMID: 38236445 DOI: 10.1007/s11033-023-09071-3] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2023] [Accepted: 11/02/2023] [Indexed: 01/19/2024]
Abstract
BACKGROUND Quorum sensing (QS) is the leading cause of persistent infections and recalcitrance to antibiotic treatment of Pseudomonas aeruginosa. Hence, QS inhibitors are promising agents for the potential treatment of P. aeruginosa infections. METHODS AND RESULTS Herein, the reducing effect of ketoprofen on virulence factors production including protease, hemolysin, pyocyanin, hydrogen cyanide, biofilm, and motility of P. aeruginosa strains was investigated. Furthermore, the quorum quenching activity of ketoprofen at the molecular level was examined by real-time PCR assessment. Our results showed that ketoprofen significantly attenuates virulence factors and biofilm formation in P. aeruginosa strains. Moreover, ketoprofen down-regulated the expression of lasI, lasR, rhlI, and rhlR genes, by 35-47, 22-48, 34-67, and 43-56%, respectively. As well, molecular docking simulation showed a high binding affinity of ketoprofen with QS regulatory proteins. CONCLUSIONS Consequently, this study confirmed the quorum quenching activity of ketoprofen, which could be employed as a useful agent for the treatment of P. aeruginosa infections.
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Affiliation(s)
- Mirsasan Mirpour
- Department of Microbiology, Lahijan Branch, Islamic Azad University, Lahijan, Iran.
| | - Hossein Zahmatkesh
- Department of Microbiology, Lahijan Branch, Islamic Azad University, Lahijan, Iran
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Faleye OS, Lee JH, Lee J. Selected flavonoids exhibit antibiofilm and antibacterial effects against Vibrio by disrupting membrane integrity, virulence and metabolic activities. Biofilm 2023; 6:100165. [PMID: 38034415 PMCID: PMC10681883 DOI: 10.1016/j.bioflm.2023.100165] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/28/2023] [Revised: 10/31/2023] [Accepted: 11/01/2023] [Indexed: 12/02/2023] Open
Abstract
Vibrio parahaemolyticus is a high-risk foodborne pathogen associated with raw or undercooked seafoods and its biofilm forming potential has become a threat to food safety and economic values. Hence, this study aims to examine the antibacterial and antibiofilm activities as well as virulence inhibitory effects of selected flavonoids against V. parahaemolyticus. Out of the sixteen flavonoid derivatives, 6-aminoflavone (6-AF), 3,2-dihydroxyflavone (3,2-DHF) and 2,2-dihydroxy-4-methoxybenzophenone (DHMB) were found as active biofilm inhibitors. 3,2-DHF and DHMB had minimum inhibitory concentrations of 20 and 50 μg/mL respectively against Vibrio planktonic cells and displayed superior antibacterial activities to standard controls. Also, they disrupted preformed biofilms and suppressed virulence properties including motilities, cell hydrophobicity and aggregation. They impaired iron acquisition mechanism and hemolysin production at sub-MICs as supported by transcriptomic studies. Interestingly, the flavonoids interfered with the metabolic activity, cell division and membrane permeability to exert antibiofilm and antibacterial activities. 6-AF and 3,2-DHF were non-toxic in the C. elegans model and showed excellent capacity to protect shrimps from biodeterioration. Furthermore, the flavonoids inhibited biofilm formation by V. harveyi, Staphylococcus aureus and Salmonella typhimurium and the mixed-species biofilm with Vibrio. This study discovered flavonoid derivatives, especially 3,2-DHF as potential bioactive compounds capable of offering protection from risks associated with biofilm formation by V. parahaemolyticus and other food pathogens.
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Affiliation(s)
- Olajide Sunday Faleye
- School of Chemical Engineering, Yeungnam University, 280 Daehak-Ro, Gyeongsan, 38541, Republic of Korea
| | - Jin-Hyung Lee
- School of Chemical Engineering, Yeungnam University, 280 Daehak-Ro, Gyeongsan, 38541, Republic of Korea
| | - Jintae Lee
- School of Chemical Engineering, Yeungnam University, 280 Daehak-Ro, Gyeongsan, 38541, Republic of Korea
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Tian L, Wang L, Yang F, Zhou T, Jiang H. Exploring the modulatory impact of isosakuranetin on Staphylococcus aureus: Inhibition of sortase A activity and α-haemolysin expression. Virulence 2023; 14:2260675. [PMID: 37733916 PMCID: PMC10543341 DOI: 10.1080/21505594.2023.2260675] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2023] [Accepted: 08/13/2023] [Indexed: 09/23/2023] Open
Abstract
The ubiquity of methicillin-resistant Staphylococcus aureus (MRSA) and the mounting prevalence of antibiotic resistance necessitate the identification of novel therapeutic approaches to reduce the selective pressure of antibiotics. Targeting bacterial virulence factors, such as the pivotal Sortase A (SrtA) in S. aureus for adhesion and invasion, and the salient toxin α-Hemolysin (Hla), offers a sophisticated approach to attenuate pathogenicity without bacterial elimination. Herein, we report the discovery of a flavonoid, isosakuranetin, which inhibits the activity of S. aureus SrtA. A fluorescence resonance energy transfer assay revealed that isosakuranetin exhibited a low IC50 of 21.20 μg/mL. Furthermore, isosakuranetin significantly inhibited SrtA-related virulence properties, such as bacterial adhesion to fibrinogen, biofilm formation, and invasion of A549 cells. We employed fluorescence quenching and molecular docking to determine the interactions between isosakuranetin and SrtA, revealing the key amino acid sites for binding. Importantly, isosakuranetin inhibited the haemolytic activity of S. aureus in vitro at a concentration of 32 μg/mL. Moreover, isosakuranetin effectively suppressed the transcription and expression of Hla in a dose-dependent manner and regulated the transcription of RNAIII, the upstream operator of Hla. Notably, isosakuranetin demonstrated in vivo efficacy in a mouse model of S. aureus-induced pneumonia by significantly improving survival rates and reducing lung damage. This is a valuable finding, as isosakuranetin's dual inhibitory effects on SrtA and haemolytic activity, as well as its anti-virulence activity against MRSA, make it an excellent candidate for therapeutic development.
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Affiliation(s)
- Lili Tian
- Institute of Animal Husbandry and Veterinary Medicine, Jinzhou Medical University, Jinzhou, China
| | - Li Wang
- Clinical Medical College, Changchun University of Chinese Medicine, Changchun, China
| | - Fengying Yang
- Institute of Animal Husbandry and Veterinary Medicine, Jinzhou Medical University, Jinzhou, China
| | - Tiezhong Zhou
- Institute of Animal Husbandry and Veterinary Medicine, Jinzhou Medical University, Jinzhou, China
| | - Hong Jiang
- Institute of Animal Husbandry and Veterinary Medicine, Jinzhou Medical University, Jinzhou, China
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Maślanka M, Tabor W, Krzyżek P, Grabowiecka A, Berlicki Ł, Mucha A. Inhibitory activity of catecholic phosphonic and phosphinic acids against Helicobacter pylori ureolysis. Eur J Med Chem 2023; 257:115528. [PMID: 37290184 DOI: 10.1016/j.ejmech.2023.115528] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/06/2023] [Revised: 05/22/2023] [Accepted: 05/25/2023] [Indexed: 06/10/2023]
Abstract
Catechols have been reported to be potent covalent inhibitors of ureases, and they exhibit activity by modifying cysteine residues at the entrance to enzymatic active sites. Following these principles, we designed and synthesized novel catecholic derivatives that contained carboxylate and phosphonic/phosphinic functionalities and assumed expanded specific interactions. When studying the chemical stability of the molecules, we found that their intrinsic acidity catalyzes spontaneous esterification/hydrolysis reactions in methanol or water solutions, respectively. Regarding biological activity, the most promising compound, 2-(3,4-dihydroxyphenyl)-3-phosphonopropionic acid (15), exhibited significant anti-urease potential (Ki = 2.36 μM, Sporosarcinia pasteurii urease), which was reflected in the antiureolytic effect in live Helicobacter pylori cells at a submicromolar concentration (IC50 = 0.75 μM). As illustrated by molecular modeling, this compound was bound in the active site of urease through a set of concerted electrostatic and hydrogen bond interactions. The antiureolytic activity of catecholic phosphonic acids could be specific because these compounds were chemically inert and not cytotoxic to eukaryotic cells.
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Affiliation(s)
- Marta Maślanka
- Department of Bioorganic Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland
| | - Wojciech Tabor
- Department of Bioorganic Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland
| | - Paweł Krzyżek
- Department of Microbiology, Faculty of Medicine, Wrocław Medical University, Wybrzeże L. Pasteura 1, 50-367, Wrocław, Poland
| | - Agnieszka Grabowiecka
- Department of Bioorganic Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland
| | - Łukasz Berlicki
- Department of Bioorganic Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland
| | - Artur Mucha
- Department of Bioorganic Chemistry, Wrocław University of Science and Technology, Wybrzeże Wyspiańskiego 27, 50-370, Wrocław, Poland.
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Ozcan A, Keskin O, Sariyar Akbulut B, Ozbek P. Piperidine-based natural products targeting Type IV pili antivirulence: A computational approach. J Mol Graph Model 2023; 119:108382. [PMID: 36463631 DOI: 10.1016/j.jmgm.2022.108382] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/19/2022] [Revised: 11/01/2022] [Accepted: 11/23/2022] [Indexed: 11/28/2022]
Abstract
Type IV (T4) pilus is among the virulence factors with a key role in serious bacterial diseases. Specifically, in Neisseria meningitidis and Pseudomonas aeruginosa, it determines pathogenicity and causes infection. Here, a computational approach has been pursued to find piperidine-based inhibitor molecules against the elongation ATPase of T4 pili in these two selected pathogens. Using the modeled structures of the PilF and PilB ATPases of N. meningitidis and P. aeruginosa, virtual library screening via molecular docking has returned inhibitor molecule candidates. The dynamics of the best three binders have further been investigated in detail via molecular dynamic simulations. Among these, ligands with COCONUT IDs CNP0030078 and CNP0051517 were found to have higher potential in the inhibition of ATPases based on molecular dynamic simulation analysis and biological activity information. The obtained results will guide future efforts in antivirulence drug development against T4 pili of N. meningitidis and P. aeruginosa.
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Affiliation(s)
- Aslihan Ozcan
- Faculty of Engineering, Department of Bioengineering, Marmara University, Istanbul, Turkey
| | - Ozlem Keskin
- College of Engineering, Chemical and Biological Engineering, Koc University, Istanbul, Turkey
| | - Berna Sariyar Akbulut
- Faculty of Engineering, Department of Bioengineering, Marmara University, Istanbul, Turkey
| | - Pemra Ozbek
- Faculty of Engineering, Department of Bioengineering, Marmara University, Istanbul, Turkey.
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11
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Liu M, Lv Q, Xu J, Liu B, Zhou Y, Zhang S, Shen X, Wang L. Isoflavone glucoside genistin, an inhibitor targeting Sortase A and Listeriolysin O, attenuates the virulence of Listeria monocytogenes in vivo and in vitro. Biochem Pharmacol 2023; 209:115447. [PMID: 36746262 DOI: 10.1016/j.bcp.2023.115447] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2022] [Revised: 01/30/2023] [Accepted: 01/31/2023] [Indexed: 02/05/2023]
Abstract
As a common intracellular facultative anaerobic Gram-positive bacterium, Listeria monocytogenes (L. monocytogenes) exhibits strong resistance to extreme environments, such as low temperature and a wide range of pH values, causing contamination in food production and processing. Sortase A (SrtA) and listeriolysin O (LLO), two crucial virulence factors of L. monocytogenes, are widely recognized as potential targets for the development of anti-L. monocytogenes infection drugs. In this study, we found that genistin simultaneously inhibits the peptidase activity of SrtA and the hemolytic activity of LLO without affecting the growth of L. monocytogenes, alleviating concerns about developing resistance. Furthermore, we demonstrated that genistin reduces L. monocytogenes biofilm formation and invasion of human colorectal cancer (Caco-2) cells. Subsequent mechanistic studies revealed that genistin inhibited LLO-mediated Caco-2 cell damage by blocking LLO oligomerization. Fluorescence quenching assay revealed the potential binding mode of SrtA and LLO to genistin. Genistin might bind to the active pocket of SrtA through residues Leu33, Asn29, and Met40, interacting with D1 domain of LLO involved in oligomerization and pore formation through residues Asn259. Studies in infection models revealed that genistin reduces mortality and pathological damage in mice infected with L. monocytogenes. These results indicate that genistin is a promising anti-virulence agent that could be considered an alternative candidate for the treatment of L. monocytogenes infection.
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Affiliation(s)
- Minda Liu
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, China
| | - Qianghua Lv
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Shandong Key Laboratory of Animal Disease Control and Breeding, Institute of Animal Science and Veterinary Medicine, Shandong Academy of Agricultural Sciences, P.R.China; Key Laboratory of Livestock and Poultry Multi-omics of MARA, P.R.China
| | - Jingwen Xu
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China
| | - Baichen Liu
- The Second Bethune Clinical Medical College of Jilin University, Changchun 130012, Jilin, People's Republic of China
| | - Yonglin Zhou
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, China
| | - Siqi Zhang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, China
| | - Xue Shen
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Food Science, College of Food Science and Engineering, Jilin University, Changchun, China.
| | - Lin Wang
- State Key Laboratory for Zoonotic Diseases, Key Laboratory for Zoonosis Research, Ministry of Education, Institute of Zoonosis, College of Veterinary Medicine, Jilin University, Changchun, China; Department of Respiratory Medicine, the First Hospital of Jilin University, Changchun, China.
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12
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Feng L, Xu M, Zeng W, Zhang X, Wang S, Yao Z, Zhou T, Shi S, Cao J, Chen L. Evaluation of the antibacterial, antibiofilm, and anti-virulence effects of acetic acid and the related mechanisms on colistin-resistant Pseudomonas aeruginosa. BMC Microbiol 2022; 22:306. [PMID: 36529724 PMCID: PMC9762083 DOI: 10.1186/s12866-022-02716-6] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 11/28/2022] [Indexed: 12/23/2022] Open
Abstract
BACKGROUND Pseudomonas aeruginosa (P. aeruginosa) has been majorly implicated in the infection of burns, wounds, skin, and respiratory tract. Colistin is considered the last line of defense against P. aeruginosa infections. However, colistin is becoming increasingly invalid in treating patients infected with colistin-resistant (COL-R) P. aeruginosa. As one of the disinfectants used for wound infections, acetic acid (AA) offers good antibacterial and antibiofilm activities against P. aeruginosa. This study investigated the effects of AA on COL-R P. aeruginosa in terms of its antibacterial, antibiofilm, and anti-virulence properties and the corresponding underlying mechanisms. RESULTS The antimicrobial susceptibility and growth curve data revealed that 0.078% (v/v) AA exhibited good antibacterial activity against COL-R P. aeruginosa. Subinhibitory concentrations of AA were ineffective in inhibiting biofilm formation, but 4 × and 8 × of the minimum inhibitory concentration (MIC) was effective in removing the preformed biofilms in biofilm-eradication assays. The virulence results illustrated that AA inhibited COL-R P. aeruginosa swimming, swarming, twitching, and pyocyanin and elastase production. The analysis of the potential antibacterial mechanisms of AA on COL-R P. aeruginosa revealed that AA acted by increasing the outer and inner membrane permeability, polarizing the membrane potential, and decreasing the reduction potential in a concentration-dependent manner. The qRT-PCR results revealed that AA may inhibit the virulence of COL-R P. aeruginosa by inhibiting the expression of T3SS-related and QS-related genes. CONCLUSIONS AA possesses antibacterial, antibiofilm, and anti-virulence properties that ultimately lead to the alteration of the bacterial membrane permeability, membrane potential, and reduction potential. Our findings indicated that AA is presently one of the effective treatment options for infections. A high concentration of AA (> 0.156% v/v) can be used to sterilize biofilm-prone surgical instruments, for hospital disinfection, and for treating the external wound, whereas a low concentration of AA (0.00975-0.039% v/v) may be used as an anti-virulence agent for adjuvant treatment of COL-R P. aeruginosa, thereby further improving the application value of AA in the treatment of infections.
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Affiliation(s)
- Luozhu Feng
- grid.414906.e0000 0004 1808 0918Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province China ,grid.268099.c0000 0001 0348 3990Department of Medical Lab Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province China
| | - Mengxin Xu
- grid.414906.e0000 0004 1808 0918Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province China
| | - Weiliang Zeng
- grid.414906.e0000 0004 1808 0918Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province China
| | - Xiaodong Zhang
- grid.414906.e0000 0004 1808 0918Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province China
| | - Sipei Wang
- grid.414906.e0000 0004 1808 0918Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province China
| | - Zhuocheng Yao
- grid.268099.c0000 0001 0348 3990Department of Medical Lab Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province China
| | - Tieli Zhou
- grid.414906.e0000 0004 1808 0918Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province China
| | - Shiyi Shi
- grid.414906.e0000 0004 1808 0918Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province China
| | - Jianming Cao
- grid.268099.c0000 0001 0348 3990Department of Medical Lab Science, School of Laboratory Medicine and Life Science, Wenzhou Medical University, Wenzhou, Zhejiang Province China
| | - Lijiang Chen
- grid.414906.e0000 0004 1808 0918Department of Clinical Laboratory, The First Affiliated Hospital of Wenzhou Medical University; Key Laboratory of Clinical Laboratory Diagnosis and Translational Research of Zhejiang Province, Wenzhou, Zhejiang Province China
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Khan F. Strategies for controlling biofilm-forming microbial pathogens on biotic and abiotic surfaces. Curr Drug Targets 2022; 23:956-959. [PMID: 35507795 DOI: 10.2174/1389450123666220429115255] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/12/2021] [Revised: 02/05/2022] [Accepted: 03/17/2022] [Indexed: 11/22/2022]
Affiliation(s)
- Fazlurrahman Khan
- Research Center for Marine Integrated Bionics Technology, Pukyong National University, Busan 48513, South Korea.,Department of Biotechnology, School of Engineering and Technology, Sharda University, Greater Noida, 201306, UP, India
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14
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Ali E, LaPointe G. Modulation of Virulence Gene Expression in Salmonella enterica subsp. enterica typhimurium by Synthetic Milk-Derived Peptides. Probiotics Antimicrob Proteins 2022; 14:690-698. [PMID: 35380388 DOI: 10.1007/s12602-022-09936-2] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/25/2022] [Indexed: 11/28/2022]
Abstract
The hydrolysis of milk proteins produces valuable bioactive peptides, some of which show antivirulence activity. In this study, five synthetic milk-derived peptides (β-LG f(9-18), β-CN f(5-15), β-CN f(17-27), β-CN f(94-106), and β-CN f(129-137)) were shown to decrease the expression of virulence genes in Salmonella enterica subsp. enterica typhimurium when tested at four concentrations (0.02, 0.05, 0.1, and 0.2 mg/ml). A mixture of these synthetic peptides at concentrations of 0.02 and 0.2 mg/ml each significantly downregulated the expression of both hilA and ssrB virulence genes in Salmonella typhimurium after a 3-h incubation. Individually, β-CN f(17-27) at 0.02 mg/ml caused a significant decrease in both hilA and ssrB gene expressions. These results suggest a synergistic interaction between bioactive peptides. Depending on dose and amino acid sequence, these five peptides were able to affect the expression of some virulence genes in Salmonella typhimurium.
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Affiliation(s)
- Eman Ali
- Food Hygiene Department, Faculty of Veterinary Medicine, Damanhour University, Damanhour El-Beheira, 22511, Egypt
| | - Gisèle LaPointe
- Department of Food Science, Canadian Research Institute for Food Safety, University of Guelph, Guelph, ON, N1G 2W1, Canada.
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15
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Elfaky MA, Abdel-Hamid MI, Khalifa E, Alshareef WA, Mosbah RA, Elazab ST, Ghoneim MM, Al-Sanea MM, Bendary MM. Innovative next-generation therapies in combating multi-drug-resistant and multi-virulent Escherichia coli isolates: insights from in vitro, in vivo, and molecular docking studies. Appl Microbiol Biotechnol 2022. [PMID: 35133473 DOI: 10.1007/s00253-022-11781-w] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/20/2021] [Revised: 01/07/2022] [Accepted: 01/13/2022] [Indexed: 02/05/2023]
Abstract
Despite notable advances in vaccine and antimicrobial therapies, treatment failure has been increasingly reported worldwide. Of note, multi-drug-resistant (MDR) Escherichia coli (E. coli) strains have a considerable share in the evolution of this crisis. So, current practice guidelines are directed towards complementary and alternative therapies. Therefore, we evaluated the antibacterial and antivirulence activities of curcumin, thymol, and eugenol essential oils (EOs) as well as EOs-EOs and EOs-antibiotics interactions on MDR and multi-virulent E. coli isolates. Unfortunately, MDR E. coli could be isolated with a prevalence rate of 95.6% (86/90). Additionally, the majority of our isolates harbored both fimH (95.6%) and ompA (91.1%) genes, and half of them (45/90) were multi-virulent. Interestingly, all the tested EOs, especially curcumin, exhibited inhibitory activities against all MDR and multi-virulent E. coli isolates. The addition of thymol enhanced the antibacterial activities of curcumin and eugenol. Moreover, the activities of piperacillin/tazobactam and imipenem were increased by adding any one of the tested EOs. Regarding the antivirulence activities of the tested EOs, the cell surfaces of treated E. coli isolates under transmission electron microscope (TEM) were uneven. The cells appeared damaged and lost their appendages. Furthermore, EOs strongly reduced the transcription of ompA and fimH genes. The antibacterial and antivirulence activities of the used EOs were confirmed by in silico and mice protection assays. Hereby, we introduced the promising uses of curcumin, thymol, and eugenol oils as complementary and alternative therapies for combating MDR and multi-virulent E. coli isolates. KEY POINTS: • Our promising results confirmed that we were right for renewed interest of EOs. • The EOs, especially curcumin, can be used to prevent treatment failure. • We supposed a new pharmaceutical formulation of antibiotic powders dissolved in EOs.
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16
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Yin N, Yang X, Wang L, Zhang C, Guan J, Tao Y, Guo X, Zhao Y, Song W, Wang B, Tang Y. Kaempferol inhibits the expression of α-hemolysin and protects mice from methicillin-resistant Staphylococcus aureus-induced lethal pneumonia. Microb Pathog 2021; 162:105336. [PMID: 34856361 DOI: 10.1016/j.micpath.2021.105336] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/09/2021] [Revised: 11/27/2021] [Accepted: 11/27/2021] [Indexed: 01/15/2023]
Abstract
Staphylococcus aureus (S. aureus) is a common pathogenic bacterium that induces a variety of diseases in humans and animals. The significant pathogenicity of S. aureus is due to its expression of several virulence factors. Alpha-hemolysin (Hla) has attracted attention as a virulence factor in staphylococcal pathogenesis and has been the predominant focus of intense research. In this study, we found that kaempferol, a flavonoid compound, inhibited hemolysis at a low concentration (32 μg/mL) and exerted no effect on bacterial growth. Western blot and RT-qPCR assays further demonstrated that kaempferol downregulated the expression of Hla in S. aureus. We observed that kaempferol alleviated the damage from S. aureus Hla in A549 cells. More importantly, kaempferol showed a potent protective effect on mice pneumonia induced by MRSA, as evidenced by a significant improvement in the survival of mice, a reduction in the number of colonized colonies in lung tissue and a decrease in the pathological damage to lung tissues. In summary, the results demonstrate the protective effect of kaempferol on MRSA-induced lethal pneumonia in mice and indicate that kaempferol could be developed as a potential anti-MRSA drug.
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Affiliation(s)
- Ning Yin
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Xin Yang
- MOE Key Laboratory of Developmental Genes and Human Disease, School of Life Science and Technology, Southeast University, Nanjing, 210096, China; Medical Science and Technology Innovation Center, Shandong First Medical University & Shandong Academy of Medical Sciences, Jinan, 271016, China
| | - Li Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Chi Zhang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Jiyu Guan
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Ye Tao
- Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, 130021, China
| | - Xuerui Guo
- Changchun University of Chinese Medicine, Changchun, 130117, China; School of Pharmacy, Jilin University, Changchun, 130021, China
| | - Yicheng Zhao
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Wu Song
- Changchun University of Chinese Medicine, Changchun, 130117, China.
| | - Bingmei Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China.
| | - Yong Tang
- Changchun University of Chinese Medicine, Changchun, 130117, China.
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Feng J, Sun D, Wang L, Li X, Guan J, Wei L, Yue D, Wang X, Zhao Y, Yang H, Song W, Wang B. Biochanin A as an α-hemolysin inhibitor for combating methicillin-resistant Staphylococcus aureus infection. World J Microbiol Biotechnol 2021; 38:6. [PMID: 34837116 DOI: 10.1007/s11274-021-03182-4] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/09/2021] [Accepted: 10/28/2021] [Indexed: 12/29/2022]
Abstract
Methicillin-resistant Staphylococcus aureus (MRSA) is a multidrug-resistant pathogen that poses a significant risk to global health today. In S. aureus, α-hemolysin is an important virulence factor as it contributes to the capacity of the bacteria to infect the host. Here, we showed that biochanin A (bioA), an isoflavone present in red clover, cabbage and alfalfa, effectively inhibited hemolytic activity at a dose as low as 32 μg/mL. Further, western blot and RT-qPCR data showed that bioA reduced the production and expression of MRSA hemolysin in a dose-dependent manner. In addition, when different concentrations of bioA were added to a coculture system of A549 cells and S. aureus, it could significantly decrease cell injury. Importantly, the in vivo study showed that bioA could protect mice from pneumonia caused by a lethal dose of MRSA, as evidenced by improving their survival and reducing the number of bacterial colonies in lung tissues, the secretion of hemolysin into alveolar lavage fluid and the degree of pulmonary edema. In conclusion, biochanin A protected the host from MRSA infection by inhibiting the expression of the hemolysin of MRSA, which may provide experimental evidence for its development to a potential anti-MRSA drug.
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Affiliation(s)
- Jiaxuan Feng
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Dazhong Sun
- First School of Clinical Medicine, Guangzhou University of Chinese Medicine, Guangzhou, 510006, China
| | - Li Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Xueting Li
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Jiyu Guan
- Key Laboratory of Zoonosis, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, China
| | - Lin Wei
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Donghui Yue
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Xingye Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Yicheng Zhao
- Changchun University of Chinese Medicine, Changchun, 130117, China
| | - Haimiao Yang
- Affiliated Hospital to Changchun University of Chinese Medicine, Changchun, 130021, China
| | - Wu Song
- Changchun University of Chinese Medicine, Changchun, 130117, China.
| | - Bingmei Wang
- Changchun University of Chinese Medicine, Changchun, 130117, China.
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Pauer H, Teixeira FL, Robinson AV, Parente TE, De Melo MAF, Lobo LA, Domingues RMCP, Allen-Vercoe E, Ferreira RBR, Antunes LCM. Bioactive small molecules produced by the human gut microbiome modulate Vibrio cholerae sessile and planktonic lifestyles. Gut Microbes 2021; 13:1-19. [PMID: 34006192 PMCID: PMC8143261 DOI: 10.1080/19490976.2021.1918993] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/04/2023] Open
Abstract
Humans live in symbiosis with a diverse community of microorganisms, which has evolved to carry out many specific tasks that benefit the host, including protection against invading pathogens. Within the chemical diversity of the gastrointestinal tract, small molecules likely constitute chemical cues for the communication between the microbiota and pathogens. Therefore, we sought to investigate if molecules produced by the human gut microbiota show biological activity against the human pathogen Vibrio cholerae. To probe the effects of the gut metabolome on V. cholerae, we investigated its response to small-molecule extracts from human feces, from a complex bacterial community cultivated in vitro, and from culture supernatants of Enterocloster citroniae, Bacteroides thetaiotaomicron, and Bacteroides vulgatus. Using RNA sequencing, we determined the impact of the human gut metabolome on V. cholerae global gene expression. Among the genes downregulated in the presence of the fecal extract, the most overrepresented functional category was cell motility, which accounted for 39% of repressed genes. Repression of V. cholerae motility by the fecal extract was confirmed phenotypically, and E. citroniae extracts reproduced this phenotype. A complex in vitro microbial community led to increased motility, as did extracts from B. vulgatus, a species present in this community. Accordingly, mucin penetration was also repressed by fecal and E. citroniae extracts, suggesting that the phenotypes observed may have implications for host colonization. Together with previous studies, this work shows that small molecules from the gut metabolome may have a widespread, significant impact on microbe-microbe interactions established in the gut environment.
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Affiliation(s)
- Heidi Pauer
- Instituto Nacional de Ciência e Tecnologia de Inovação Em Doenças De Populações Negligenciadas, Centro De Desenvolvimento Tecnológico em Saúde, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Felipe Lopes Teixeira
- Departamento de Tecnologia Farmacêutica, Universidade Federal Fluminense, Niterói, Brazil
| | - Avery V. Robinson
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Canada
| | - Thiago E. Parente
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Marília A. F. De Melo
- Laboratório de Genômica Funcional e Bioinformática, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil
| | - Leandro A. Lobo
- Departamento de Microbiologia Médica, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio De Janeiro, Rio de Janeiro, Brazil
| | - Regina M. C. P. Domingues
- Departamento de Microbiologia Médica, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio De Janeiro, Rio de Janeiro, Brazil
| | - Emma Allen-Vercoe
- Department of Molecular and Cellular Biology, University of Guelph, Guelph, Canada
| | - Rosana B. R. Ferreira
- Departamento de Microbiologia Médica, Instituto de Microbiologia Paulo de Góes, Universidade Federal do Rio De Janeiro, Rio de Janeiro, Brazil
| | - Luis Caetano M. Antunes
- Instituto Nacional de Ciência e Tecnologia de Inovação Em Doenças De Populações Negligenciadas, Centro De Desenvolvimento Tecnológico em Saúde, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil,Escola Nacional de Saúde Pública Sergio Arouca, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil,Laboratório de Pesquisa Em Infecção Hospitalar, Instituto Oswaldo Cruz, Fundação Oswaldo Cruz, Rio de Janeiro, Brazil,CONTACT Luis Caetano Antunes Avenida Brasil, 4365, Manguinhos, Rio de Janeiro, RJ, 21040-900
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Duncan LF, Wang G, Ilyichova OV, Dhouib R, Totsika M, Scanlon MJ, Heras B, Abbott BM. Elaboration of a benzofuran scaffold and evaluation of binding affinity and inhibition of Escherichia coli DsbA: A fragment-based drug design approach to novel antivirulence compounds. Bioorg Med Chem 2021; 45:116315. [PMID: 34364222 DOI: 10.1016/j.bmc.2021.116315] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2021] [Revised: 07/15/2021] [Accepted: 07/16/2021] [Indexed: 11/20/2022]
Abstract
Bacterial thiol-disulfide oxidoreductase DsbA is essential for bacterial virulence factor assembly and has been identified as a viable antivirulence target. Herein, we report a structure-based elaboration of a benzofuran hit that bound to the active site groove of Escherichia coli DsbA. Substituted phenyl groups were installed at the 5- and 6-position of the benzofuran using Suzuki-Miyaura coupling. HSQC NMR titration experiments showed dissociation constants of this series in the high µM to low mM range and X-ray crystallography produced three co-structures, showing binding in the hydrophobic groove, comparable with that of the previously reported benzofurans. The 6-(m-methoxy)phenyl analogue (2b), which showed a promising binding pose, was chosen for elaboration from the C-2 position. The 2,6-disubstituted analogues bound to the hydrophobic region of the binding groove and the C-2 groups extended into the more polar, previously un-probed, region of the binding groove. Biochemical analysis of the 2,6-disubsituted analogues showed they inhibited DsbA oxidation activity in vitro. The results indicate the potential to develop the elaborated benzofuran series into a novel class of antivirulence compounds.
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Palaniappan B, Solomon AP, C DR. Targeting AgrA quorum sensing regulator by bumetanide attenuates virulence in Staphylococcus aureus - A drug repurposing approach. Life Sci 2021; 273:119306. [PMID: 33662434 DOI: 10.1016/j.lfs.2021.119306] [Citation(s) in RCA: 19] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/17/2020] [Revised: 02/23/2021] [Accepted: 02/24/2021] [Indexed: 11/29/2022]
Abstract
AIMS The present study aims to target the quorum sensing (QS) accessory gene regulator A (AgrA) of Staphylococcus aureus to curtail bacterial virulence through drug repurposing approach. MAIN METHODS In silico screening of chemical ligands that bind specifically to the S. aureus C-LytTR domain of AgrA (AgrAC) was carried out. AgrA inhibition and downregulation of virulence genes linked to QS system of S. aureus were determined. Efficacy, dermal toxicity and drug tolerance induction were tested in Balb/C mice dermonecrosis model. KEY FINDINGS Bumetanide bound to the conserved amino acid Tyr-229 of AgrA and showed 70% AgrA inhibition at 0.1 μM. Highly significant reduction in the expression of representative virulence genes such as alpha-hemolysin (~5 log2-fold), phenol-soluble modulins (~4 log2-fold) and panton-valentine leukocidin (~3 log2-fold) was noted in vitro. In vivo studies signified bumetanide to be highly effective in controlling the ulcer development and promoted wound healing. Also, the tested substance did not have dermal toxicity and no tolerance induction as well. SIGNIFICANCE Targeting the QS regulators could be a possible alternative approach to curtail virulence in S. aureus. In addition, if the QS inhibitors are repurposed it could accelerate the drug development process and reduce the cost. The identified drug bumetanide inhibited AgrA and the results were in comparable to that of a known virulence inhibitor, diflunisal. The newly reported results of bumetanide in this study are expected to mark the drug's visibility for antibiotic adjunctive therapy and topical drug formulations for skin infections research.
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Affiliation(s)
- Balamurugan Palaniappan
- Quorum Sensing Laboratory, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur 613401, Tamil Nadu, India.
| | - Adline Princy Solomon
- Quorum Sensing Laboratory, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur 613401, Tamil Nadu, India.
| | - David Raj C
- Central Animal Facility, School of Chemical and Biotechnology, SASTRA Deemed University, Thanjavur 613401, Tamil Nadu, India
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Vij R, Hube B, Brunke S. Uncharted territories in the discovery of antifungal and antivirulence natural products from bacteria. Comput Struct Biotechnol J 2021; 19:1244-1252. [PMID: 33680363 PMCID: PMC7905183 DOI: 10.1016/j.csbj.2021.02.003] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2020] [Revised: 02/02/2021] [Accepted: 02/02/2021] [Indexed: 12/26/2022] Open
Abstract
Many fungi can cause deadly diseases in humans, and nearly every human will suffer from some kind of fungal infection in their lives. Only few antifungals are available, and some of these fail to treat intrinsically resistant species and the ever-increasing number of fungal strains that have acquired resistance. In nature, bacteria and fungi display versatile interactions that range from friendly co-existence to predation. The first antifungal drugs, nystatin and amphotericin B, were discovered in bacteria as mediators of such interactions, and bacteria continue to be an important source of antifungals. To learn more about the ecological bacterial-fungal interactions that drive the evolution of natural products and exploit them, we need to identify environments where such interactions are pronounced, and diverse. Here, we systematically analyze historic and recent developments in this field to identify potentially under-investigated niches and resources. We also discuss alternative strategies to treat fungal infections by utilizing the antagonistic potential of bacteria to target fungal stress pathways and virulence factors, and thereby suppress the evolution of antifungal resistance.
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Affiliation(s)
- Raghav Vij
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Germany
| | - Bernhard Hube
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Germany
- Institute of Microbiology, Friedrich Schiller University, Jena, Germany
| | - Sascha Brunke
- Department of Microbial Pathogenicity Mechanisms, Leibniz Institute for Natural Product Research and Infection Biology – Hans Knoell Institute Jena (HKI), Germany
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Durgadevi R, Abirami G, Swasthikka RP, Alexpandi R, Pandian SK, Ravi AV. Proteomic analysis deciphers the multi-targeting antivirulence activity of tannic acid in modulating the expression of MrpA, FlhD, UreR, HpmA and Nrp system in Proteus mirabilis. Int J Biol Macromol 2020; 165:1175-1186. [PMID: 33007322 DOI: 10.1016/j.ijbiomac.2020.09.233] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/24/2020] [Revised: 08/08/2020] [Accepted: 09/25/2020] [Indexed: 12/28/2022]
Abstract
In the present study, the multi-targeting antivirulence activity of tannic acid (TA) was explored against Proteus mirabilis through MS-based proteomic approach. The in vitro biofilm biomass quantification assay and microscopic analysis demonstrated the antibiofilm activity of TA against P. mirabilis in which, minimum biofilm inhibitory concentration (MBIC) of TA was found to be 200 μg/mL concentration. Moreover, the nanoscale liquid chromatography coupled to tandem mass spectrometry (nano LC-MS/MS) analysis revealed that TA (at MBIC) differentially regulated the proteins involved in fimbrial adhesion, flagellar motility, iron acquisition, Fe-S cluster assembly, heat shock response, virulence enzymes, and toxin secretion. Further, the transcriptomic analysis validated the outcomes of proteomic analysis in which, the expression level of virulence genes responsible for MR/P fimbrial adhesion (mrpA), flagellar transcriptional activation (flhD), biosynthesis of urease (ureR), hemolysin (hpmA), non-ribosomal peptide siderophore system (Nrp), oxidative stress responsible enzymes and fitness factors proteins were down-regulated in TA exposed P. mirabilis. These observations were also in correspondence with the in vitro bioassays. Thus, this study reports the feasibility of TA to act as a promising therapeutic agent against multifactorial P. mirabilis infections.
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Affiliation(s)
- Ravindran Durgadevi
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi 630 003, Tamil Nadu, India
| | - Gurusamy Abirami
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi 630 003, Tamil Nadu, India
| | | | - Rajaiah Alexpandi
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi 630 003, Tamil Nadu, India
| | | | - Arumugam Veera Ravi
- Department of Biotechnology, Alagappa University, Science Campus, Karaikudi 630 003, Tamil Nadu, India.
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Lv H, Fang T, Kong F, Wang J, Deng X, Yu Q, Sun M, Liang X. Dryocrassin ABBA ameliorates Streptococcus pneumoniae-induced infection in vitro through inhibiting Streptococcus pneumoniae growth and neutralizing pneumolysin activity. Microb Pathog 2020; 150:104683. [PMID: 33309685 DOI: 10.1016/j.micpath.2020.104683] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/14/2020] [Revised: 11/06/2020] [Accepted: 12/02/2020] [Indexed: 10/22/2022]
Abstract
To explore the role of dryocrassin ABBA (ABBA) in the prevention and treatment of Streptococcus pneumoniae (S. pneumoniae) infections in vitro, a minimal inhibitory concentration test, growth curve assay, hemolysis assay, BacLight LIVE/DEAD staining experiments, oligomerization inhibition assay, time-killing test, LDH release detection assay and cytotoxicity test were performed to evaluate the efficacy of ABBA against S. pneumoniae infections in vitro. The results indicated that ABBA treatment exists bactericidal effect on S. pneumoniae at a concentration of less than 8 μg/ml. Furthermore, ABBA was effective at inhibiting the oligomerization of pneumolysin (PLY) from reducing its hemolytic activity. Meanwhile, ABBA could ameliorate cell injury by neutralizing the biological activity of PLY without cytotoxicity. In summary, ABBA was a leading compound against S. pneumoniae infections through bactericidal effect and neutralizing PLY activity.
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Affiliation(s)
- Hongfa Lv
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, Jilin, China
| | - Tianqi Fang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, Jilin, China
| | - Fanrong Kong
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, Jilin, China
| | - Jianfeng Wang
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, Jilin, China
| | - Xuming Deng
- Key Laboratory of Zoonosis Research, Ministry of Education, College of Veterinary Medicine, Jilin University, Changchun, 130062, Jilin, China
| | - Qinlei Yu
- Jilin Provincial Animal Disease Control Center, 4510 Xi'an Road, Changchun, 130062, China
| | - Meiyang Sun
- Department of Breast Surgery, Jilin Provincial Cancer Hospital, Changchun, China.
| | - Xiaoying Liang
- Department of Internal Medicine, University of South Florida, Tampa, FL, USA.
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Pollock J, Low AS, McHugh RE, Muwonge A, Stevens MP, Corbishley A, Gally DL. Alternatives to antibiotics in a One Health context and the role genomics can play in reducing antimicrobial use. Clin Microbiol Infect 2020; 26:1617-1621. [PMID: 32220638 DOI: 10.1016/j.cmi.2020.02.028] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/10/2019] [Revised: 02/19/2020] [Accepted: 02/22/2020] [Indexed: 01/16/2023]
Abstract
BACKGROUND This review follows on from the International Conference on One Health Antimicrobial Resistance (ICOHAR 2019), where strategies to improve the fundamental understanding and management of antimicrobial resistance at the interface between humans, animals and the environment were discussed. OBJECTIVE This review identifies alternatives to antimicrobials in a One Health context, noting how advances in genomic technologies are assisting their development and enabling more targeted use of antimicrobials. SOURCES Key articles on the use of microbiota modulation, livestock breeding and gene editing, vaccination, antivirulence strategies and bacteriophage therapy are discussed. CONTENT Antimicrobials are central for disease control, but reducing their use is paramount as a result of the rise of transmissible antimicrobial resistance. This review discusses antimicrobial alternatives in the context of improved understanding of fundamental host-pathogen and microbiota interactions using genomic tools. IMPLICATIONS Host and microbial genomics and other novel technologies play an important role in devising disease control strategies for healthier animals and humans that in turn reduce our reliance on antimicrobials.
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Affiliation(s)
- J Pollock
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Edinburgh, UK
| | - A S Low
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Edinburgh, UK
| | - R E McHugh
- Institute of Infection, Immunity & Inflammation, University of Glasgow, Glasgow, Scotland, UK; Strathclyde Institute of Pharmacy and Biomedical Sciences, University of Strathclyde, Glasgow, Scotland, UK
| | - A Muwonge
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Edinburgh, UK
| | - M P Stevens
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Edinburgh, UK
| | - A Corbishley
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Edinburgh, UK
| | - D L Gally
- The Roslin Institute and Royal (Dick) School of Veterinary Studies, Edinburgh, UK.
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Kreling V, Falcone FH, Kehrenberg C, Hensel A. Campylobacter sp.: Pathogenicity factors and prevention methods-new molecular targets for innovative antivirulence drugs? Appl Microbiol Biotechnol 2020; 104:10409-10436. [PMID: 33185702 PMCID: PMC7662028 DOI: 10.1007/s00253-020-10974-5] [Citation(s) in RCA: 31] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2020] [Revised: 08/24/2020] [Accepted: 10/21/2020] [Indexed: 02/08/2023]
Abstract
Infections caused by bacterial species from the genus Campylobacter are one of the four main causes of strong diarrheal enteritis worldwide. Campylobacteriosis, a typical food-borne disease, can range from mild symptoms to fatal illness. About 550 million people worldwide suffer from campylobacteriosis and lethality is about 33 million p.a. This review summarizes the state of the current knowledge on Campylobacter with focus on its specific virulence factors. Using this knowledge, multifactorial prevention strategies can be implemented to reduce the prevalence of Campylobacter in the food chain. In particular, antiadhesive strategies with specific adhesion inhibitors seem to be a promising concept for reducing Campylobacter bacterial load in poultry production. Antivirulence compounds against bacterial adhesion to and/or invasion into the host cells can open new fields for innovative antibacterial agents. Influencing chemotaxis, biofilm formation, quorum sensing, secretion systems, or toxins by specific inhibitors can help to reduce virulence of the bacterium. In addition, the unusual glycosylation of the bacterium, being a prerequisite for effective phase variation and adaption to different hosts, is yet an unexplored target for combating Campylobacter sp. Plant extracts are widely used remedies in developing countries to combat infections with Campylobacter. Therefore, the present review summarizes the use of natural products against the bacterium in an attempt to stimulate innovative research concepts on the manifold still open questions behind Campylobacter towards improved treatment and sanitation of animal vectors, treatment of infected patients, and new strategies for prevention. KEY POINTS: • Campylobacter sp. is a main cause of strong enteritis worldwide. • Main virulence factors: cytolethal distending toxin, adhesion proteins, invasion machinery. • Strong need for development of antivirulence compounds.
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Affiliation(s)
- Vanessa Kreling
- Institute of Pharmaceutical Biology and Phytochemistry, University of Münster, Corrensstraße 48, 48149, Münster, Germany
| | - Franco H Falcone
- Institute of Parasitology, University of Gießen, Schubertstraße 81, 35392, Gießen, Germany
| | - Corinna Kehrenberg
- Institute of Veterinary Food Science, University of Gießen, Frankfurterstraße 81, 35392, Gießen, Germany
| | - Andreas Hensel
- Institute of Pharmaceutical Biology and Phytochemistry, University of Münster, Corrensstraße 48, 48149, Münster, Germany.
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Aksoy CS, Avci FG, Ugurel OM, Atas B, Sayar NA, Sariyar Akbulut B. Potentiating the activity of berberine for Staphylococcus aureus in a combinatorial treatment with thymol. Microb Pathog 2020; 149:104542. [PMID: 33010366 DOI: 10.1016/j.micpath.2020.104542] [Citation(s) in RCA: 10] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/05/2020] [Revised: 06/29/2020] [Accepted: 09/28/2020] [Indexed: 02/06/2023]
Abstract
A plethora of natural products emerges as attractive molecules in the struggle against antibiotic resistance. These molecules impose their bioactivities not only alone but also in combinations as well, which further enhances their effects. Berberine is a well-known isoquinoline alkaloid with antibacterial activity. Unfortunately, it is readily extruded, which significantly reduces its efficacy and restricts its potential. Thymol is a monoterpenic phenol that exhibits different biological activities but its major effect is observed only at relatively high concentrations, which raises concern on cytotoxicity. The aim of the study was to potentiate the antibacterial activity of berberine, in a combination treatment with thymol in the opportunistic pathogen Staphylococcus aureus and understand the antibacterial mechanism of the combination treatment. The synergism of berberine and thymol was first established by the checkerboard assay. Then the antibacterial mechanism of the synergistic combination was explored by growth curves, biofilm formation assay, SEM observation, and RNA-Seq based transcriptomic profiling. Checkerboard assay showed that 32 μg mL-1 berberine and 64 μg mL-1 thymol was a synergistic combination, both concentrations below their cytotoxicity limits for many cells. 32 μg mL-1 berberine and 32 μg mL-1 thymol was sufficient to inhibit biofilm formation. SEM images confirmed the morphological changes on the structure of combination treated cells. The major finding of the combination treatment from the transcriptomic analysis was the repression in the expression of virulence factors or genes related to virulence factors. Apart from the particular changes related to the cell envelope, the majority of expressional changes seemed to be similar to berberine-treated cells or to be resulting from general stress conditions. The findings of this work showed that when thymol was used in combination with berberine, it enhanced the antibacterial activity of berberine in a synergistic manner. Furthermore, thymol could be considered as an antivirulence agent, disarming S. aureus cells.
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Abutaleb NS, Seleem MN. Antivirulence activity of auranofin against vancomycin-resistant enterococci: in vitro and in vivo studies. Int J Antimicrob Agents 2019; 55:105828. [PMID: 31669742 DOI: 10.1016/j.ijantimicag.2019.10.009] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/10/2019] [Revised: 09/13/2019] [Accepted: 10/20/2019] [Indexed: 02/05/2023]
Abstract
INTRODUCTION Vancomycin-resistant enterococci (VRE) are a leading cause of nosocomial infections because of the limited number of effective therapeutic options. In an effort to repurpose FDA-approved drugs against antibiotic-resistant bacteria, auranofin has been identified as a potent drug against VRE. METHODS AND RESULTS The present study determined that auranofin's antibacterial activity was not affected when evaluated against a higher inoculum size of VRE (~107 CFU/mL), and auranofin successfully reduced the burden of stationary phase VRE cells via a time-kill assay. In addition, auranofin reduced VRE production of key virulence factors, including proteases, lipase and haemagglutinin. The promising features of auranofin prompted evaluation of its in vivo efficacy in a lethal mouse model of VRE septicaemia. All mice receiving auranofin at 0.125 mg/kg orally, 0.125 mg/kg subcutaneously (SC) or 0.0625 mg/kg (SC) survived the lethal VRE challenge. Additionally, auranofin was superior to linezolid, the current drug of choice, in reducing VRE burden in the liver, kidneys and spleen of mice. Remarkably, auranofin successfully reduced VRE below the limit of detection in murine internal organs after 4 days of oral or subcutaneous treatment. CONCLUSION These results indicate that auranofin warrants further investigation as a new treatment for systemic VRE infections.
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Affiliation(s)
- Nader S Abutaleb
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA
| | - Mohamed N Seleem
- Department of Comparative Pathobiology, College of Veterinary Medicine, Purdue University, West Lafayette, IN, USA; Purdue Institute of Inflammation, Immunology, and Infectious Disease, West Lafayette, IN, USA.
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Vestergaard M, Ingmer H. Antibacterial and antifungal properties of resveratrol. Int J Antimicrob Agents 2019; 53:716-723. [PMID: 30825504 DOI: 10.1016/j.ijantimicag.2019.02.015] [Citation(s) in RCA: 201] [Impact Index Per Article: 40.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/10/2018] [Revised: 02/13/2019] [Accepted: 02/16/2019] [Indexed: 12/30/2022]
Abstract
Resveratrol is a naturally occurring polyphenolic antioxidant that has received massive attention for its potential health benefits, including anticarcinogenesis, anti-aging and antimicrobial properties. The compound is well tolerated by humans and in recent years has been widely used as a nutraceutical. Its common use makes it interesting to investigate with respect to antimicrobial properties both as a single agent and in combination with conventional antibiotics. Resveratrol displays antimicrobial activity against a surprisingly wide range of bacterial, viral and fungal species. At subinhibitory concentrations, resveratrol can alter bacterial expression of virulence traits leading to reduced toxin production, inhibition of biofilm formation, reduced motility and interference with quorum sensing. In combination with conventional antibiotics, resveratrol enhances the activity of aminoglycosides against Staphylococcus aureus, whereas it antagonises the lethal activity of fluoroquinolones against S. aureus and Escherichia coli. Whilst the antimicrobial properties of the compound have been extensively studied in vitro, little is known about its efficacy in vivo. Nonetheless, following topical application resveratrol has alleviated acne lesions caused by the bacterium Propionibacterium acnes. There are currently no in vivo studies addressing its effect in combination with antibiotics, but recent research suggests that there may be a potential for enhancing the antimicrobial efficacy of certain existing antibiotic classes in combination with resveratrol. Given the difficulties associated with introducing new antimicrobial agents to the market, nutraceuticals such as resveratrol may prove to be interesting candidates when searching for solutions for the growing problem of antimicrobial resistance.
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Affiliation(s)
- Martin Vestergaard
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, DK-1870 Frederiksberg C, Denmark
| | - Hanne Ingmer
- Department of Veterinary and Animal Sciences, Faculty of Health and Medical Sciences, University of Copenhagen, Stigbøjlen 4, DK-1870 Frederiksberg C, Denmark.
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Liu Y, Mi Z, Mi L, Huang Y, Li P, Liu H, Yuan X, Niu W, Jiang N, Bai C, Gao Z. Identification and characterization of capsule depolymerase Dpo48 from Acinetobacter baumannii phage IME200. PeerJ 2019; 7:e6173. [PMID: 30656071 PMCID: PMC6336015 DOI: 10.7717/peerj.6173] [Citation(s) in RCA: 34] [Impact Index Per Article: 6.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/11/2018] [Accepted: 11/28/2018] [Indexed: 12/16/2022] Open
Abstract
Background The emergence of multidrug- or extensively drug-resistant Acinetobacter baumannii has made it difficult to treat and control infections caused by this bacterium. It is urgently necessary to search for alternatives to conventional antibiotics for control of severe A. baumannii infections. In recent years, bacteriophages and their derivatives, such as depolymerases, showed great potential as antibacterial or antivirulence agents against bacterial infections. Nonetheless, unlike broad-spectrum bactericidal antibiotics, phage-encoded depolymerase targets only a limited number of bacterial strains. Therefore, identification of novel depolymerases and evaluation of their ability to control A. baumannii infections is important. Methods A bacteriophage was isolated from hospital sewage using an extensively drug-resistant A. baumannii strain as the host bacterium, and the phage’s plaque morphology and genomic composition were studied. A polysaccharide depolymerase (Dpo48) was expressed and identified, and the effects of pH and temperature on its activity were determined. Besides, a serum killing assay was conducted, and amino acid sequences homologous to those of putative polysaccharide depolymerases were compared. Results Phage IME200 yielded clear plaques surrounded by enlarged halos, with polysaccharide depolymerase activity against the host bacterium. A tail fiber protein with a Pectate_lyase_3 domain was identified as Dpo48 and characterized . Dpo48 was found to degrade the capsule polysaccharide of the bacterial surface, as revealed by Alcian blue staining. Dpo48 manifested stable activity over a broad range of pH (5.0–9.0) and temperatures (20–70 °C). Results from in vitro serum killing assays indicated that 50% serum was sufficient to cause a five log reduction of overnight enzyme-treated bacteria, with serum complement playing an important role in these killing assays. Moreover, Dpo48 had a spectrum of activity exactly the same as its parental phage IME200, which was active against 10 out of 41 A. baumannii strains. Amino acid sequence alignment showed that the putative tail fiber proteins had a relatively short, highly conserved domain in their N-terminal sequences, but their amino acid sequences containing pectate lyase domains, found in the C-terminal regions, were highly diverse. Conclusions Phage-encoded capsule depolymerases may become promising antivirulence agents for preventing and controlling A. baumannii infections.
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Affiliation(s)
- Yannan Liu
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China.,Department of Respiratory and Critical Care Medicine, 307th Hospital of PLA, Beijing, China
| | - Zhiqiang Mi
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Liyuan Mi
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Yong Huang
- State Key Laboratory of Pathogen and Biosecurity, Beijing Institute of Microbiology and Epidemiology, Beijing, China
| | - Puyuan Li
- Department of Respiratory and Critical Care Medicine, 307th Hospital of PLA, Beijing, China
| | - Huiying Liu
- Department of Respiratory and Critical Care Medicine, 307th Hospital of PLA, Beijing, China
| | - Xin Yuan
- Department of Respiratory and Critical Care Medicine, 307th Hospital of PLA, Beijing, China
| | - Wenkai Niu
- Department of Respiratory and Critical Care Medicine, 307th Hospital of PLA, Beijing, China
| | - Ning Jiang
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China
| | - Changqing Bai
- Department of Respiratory and Critical Care Medicine, 307th Hospital of PLA, Beijing, China
| | - Zhancheng Gao
- Department of Respiratory and Critical Care Medicine, Peking University People's Hospital, Beijing, China
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Wójcik M, Eleftheriadis N, Zwinderman MRH, Dömling ASS, Dekker FJ, Boersma YL. Identification of potential antivirulence agents by substitution-oriented screening for inhibitors of Streptococcus pyogenes sortase A. Eur J Med Chem 2018; 161:93-100. [PMID: 30343193 DOI: 10.1016/j.ejmech.2018.10.027] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/20/2018] [Revised: 10/02/2018] [Accepted: 10/10/2018] [Indexed: 10/28/2022]
Abstract
Antimicrobial resistance resulting in ineffective treatment of infectious diseases is an increasing global problem, particularly in infections with pathogenic bacteria. In some bacteria, such as Streptococcus pyogenes, the pathogenicity is strongly linked to the attachment of virulence factors. Their attachment to the cellular membrane is a transpeptidation reaction, catalyzed by sortase enzymes. As such, sortases pose an interesting target for the development of new antivirulence strategies that could yield novel antimicrobial drugs. Using the substitution-oriented fragment screening (SOS) approach, we discovered a potent and specific inhibitor (C10) of sortase A from S. pyogenes. The inhibitor C10 showed high specificity towards S. pyogenes sortase A, with an IC50 value of 10 μM and a Kd of 60 μM. We envision that this inhibitor could be employed as a starting point for further exploration of sortase's potential as therapeutic target for antimicrobial drug development.
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Affiliation(s)
- Magdalena Wójcik
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Chemical and Pharmaceutical Biology, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands.
| | - Nikolaos Eleftheriadis
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Chemical and Pharmaceutical Biology, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands; University of Groningen, Molecular Microscopy Research Group, Zernike Institute for Advanced Materials, Nijenborgh 4, 9747 AG, Groningen, the Netherlands.
| | - Martijn R H Zwinderman
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Chemical and Pharmaceutical Biology, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands.
| | - Alexander S S Dömling
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Drug Design, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands.
| | - Frank J Dekker
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Chemical and Pharmaceutical Biology, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands.
| | - Ykelien L Boersma
- University of Groningen, Groningen Research Institute of Pharmacy, Department of Chemical and Pharmaceutical Biology, Antonius Deusinglaan 1, 9713 AV, Groningen, the Netherlands.
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Lee JH, Kim YG, Shim SH, Lee J. Antibiofilm activities of norharmane and its derivatives against Escherichia coli O157:H7 and other bacteria. Phytomedicine 2017; 36:254-261. [PMID: 29157822 DOI: 10.1016/j.phymed.2017.10.013] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/16/2017] [Revised: 09/19/2017] [Accepted: 10/17/2017] [Indexed: 05/02/2023]
Abstract
BACKGROUND Bacterial biofilms exhibit reduced sensitivity to conventional antibiotics and host defence systems and contribute to the persistence of chronic bacterial infections. HYPOTHESIS The antibiofilm approach using plant alkaloids provides an alternative to antibiotic strategies. STUDY DESIGN In this study, the antibiofilm activities of various plant alkaloids were investigated against enterohemorrhagic Escherichia coli O157:H7 and Pseudomonas aeruginosa. In the subsequent investigation, the effects of five norharmane derivatives were investigated. RESULT Harmaline significantly inhibited biofilm formation by E. coli O157:H7, P. aeruginosa PAO1, P. aeruginosa PA14, and Klebsiella oxytoca, and norharmane (β-carboline) was found to have antibiofilm activity. It was also found that functional groups at the C-1 and C-7 positions of norharmane could play important roles in its antibiofilm activity. Confocal and electron microscopic observations confirmed biofilm inhibition by harmaline and norharmane, and both reduced fimbriae production and swarming and swimming motilities. Furthermore, harmaline and norharmane attenuated the virulence of E. coli O157:H7 in a Caenorhabditis elegans nematode model. CONCLUSION These findings strongly suggest that harmaline and norharmane could have potential use in antibiofilm strategy against persistent bacterial infections.
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Affiliation(s)
- Jin-Hyung Lee
- School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Yong-Guy Kim
- School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea
| | - Sang Hee Shim
- College of Pharmacy, Duksung Women's University, Seoul 01369, Republic of Korea.
| | - Jintae Lee
- School of Chemical Engineering, Yeungnam University, Gyeongsan 38541, Republic of Korea.
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Walsh SI, Craney A, Romesberg FE. Not just an antibiotic target: Exploring the role of type I signal peptidase in bacterial virulence. Bioorg Med Chem 2016; 24:6370-6378. [PMID: 27769673 PMCID: PMC5279723 DOI: 10.1016/j.bmc.2016.09.048] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2016] [Revised: 09/17/2016] [Accepted: 09/19/2016] [Indexed: 01/23/2023]
Abstract
The looming antibiotic crisis has prompted the development of new strategies towards fighting infection. Traditional antibiotics target bacterial processes essential for viability, whereas proposed antivirulence approaches rely on the inhibition of factors that are required only for the initiation and propagation of infection within a host. Although antivirulence compounds have yet to prove their efficacy in the clinic, bacterial signal peptidase I (SPase) represents an attractive target in that SPase inhibitors exhibit broad-spectrum antibiotic activity, but even at sub-MIC doses also impair the secretion of essential virulence factors. The potential consequences of SPase inhibition on bacterial virulence have not been thoroughly examined, and are explored within this review. In addition, we review growing evidence that SPase has relevant biological functions outside of mediating secretion, and discuss how the inhibition of these functions may be clinically significant.
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Affiliation(s)
- Shawn I Walsh
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Arryn Craney
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
| | - Floyd E Romesberg
- Department of Chemistry, The Scripps Research Institute, 10550 North Torrey Pines Road, La Jolla, CA 92037, USA
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Cushnie TP, Cushnie B, Lamb AJ. Alkaloids: an overview of their antibacterial, antibiotic-enhancing and antivirulence activities. Int J Antimicrob Agents 2014; 44:377-86. [PMID: 25130096 DOI: 10.1016/j.ijantimicag.2014.06.001] [Citation(s) in RCA: 329] [Impact Index Per Article: 32.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2014] [Accepted: 06/20/2014] [Indexed: 11/22/2022]
Abstract
With reports of pandrug-resistant bacteria causing untreatable infections, the need for new antibacterial therapies is more pressing than ever. Alkaloids are a large and structurally diverse group of compounds that have served as scaffolds for important antibacterial drugs such as metronidazole and the quinolones. In this review, we highlight other alkaloids with development potential. Natural, semisynthetic and synthetic alkaloids of all classes are considered, looking first at those with direct antibacterial activity and those with antibiotic-enhancing activity. Potent examples include CJ-13,136, a novel actinomycete-derived quinolone alkaloid with a minimum inhibitory concentration of 0.1 ng/mL against Helicobacter pylori, and squalamine, a polyamine alkaloid from the dogfish shark that renders Gram-negative pathogens 16- to >32-fold more susceptible to ciprofloxacin. Where available, information on toxicity, structure-activity relationships, mechanisms of action and in vivo activity is presented. The effects of alkaloids on virulence gene regulatory systems such as quorum sensing and virulence factors such as sortases, adhesins and secretion systems are also described. The synthetic isoquinoline alkaloid virstatin, for example, inhibits the transcriptional regulator ToxT in Vibrio cholerae, preventing expression of cholera toxin and fimbriae and conferring in vivo protection against intestinal colonisation. The review concludes with implications and limitations of the described research and directions for future research.
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McMahon RM, Premkumar L, Martin JL. Four structural subclasses of the antivirulence drug target disulfide oxidoreductase DsbA provide a platform for design of subclass-specific inhibitors. Biochim Biophys Acta 2014; 1844:1391-401. [PMID: 24487020 DOI: 10.1016/j.bbapap.2014.01.013] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2013] [Revised: 12/19/2013] [Accepted: 01/22/2014] [Indexed: 01/11/2023]
Abstract
By catalyzing oxidative protein folding, the bacterial disulfide bond protein A (DsbA) plays an essential role in the assembly of many virulence factors. Predictably, DsbA disruption affects multiple downstream effector molecules, resulting in pleiotropic effects on the virulence of important human pathogens. These findings mark DsbA as a master regulator of virulence, and identify the enzyme as a target for a new class of antivirulence agents that disarm pathogenic bacteria rather than killing them. The purpose of this article is to discuss and expand upon recent findings on DsbA and to provide additional novel insights into the druggability of this important disulfide oxidoreductase by comparing the structures and properties of 13 well-characterized DsbA enzymes. Our structural analysis involved comparison of the overall fold, the surface properties, the conformations of three loops contributing to the binding surface and the sequence identity of residues contributing to these loops. Two distinct structural classes were identified, classes I and II, which are differentiated by their central β-sheet arrangements and which roughly separate the DsbAs produced by Gram-negative from Gram-positive organisms. The classes can be further subdivided into a total of four subclasses on the basis of surface features. Class Ia is equivalent to the Enterobacteriaceae class that has been defined previously. Bioinformatic analyses support the classification of DsbAs into 3 of the 4 subclasses, but did not pick up the 4th subclass which is only apparent from analysis of DsbA electrostatic surface properties. In the context of inhibitor development, the discrete structural subclasses provide a platform for developing DsbA inhibitory scaffolds with a subclass-wide spectrum of activity. We expect that more DsbA classes are likely to be identified, as enzymes from other pathogens are explored, and we highlight the issues associated with structure-based inhibitor development targeting this pivotal mediator of bacterial virulence. This article is part of a Special Issue entitled: Thiol-Based Redox Processes.
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Affiliation(s)
- Róisín M McMahon
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, University of Queensland, St Lucia, Queensland 4072, Australia.
| | - Lakshmanane Premkumar
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, University of Queensland, St Lucia, Queensland 4072, Australia.
| | - Jennifer L Martin
- Division of Chemistry and Structural Biology, Institute for Molecular Bioscience, University of Queensland, St Lucia, Queensland 4072, Australia.
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