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Arfaoui A, Rojo-Bezares B, Fethi M, López M, Toledano P, Sayem N, Ben Khelifa Melki S, Ouzari HI, Klibi N, Sáenz Y. Molecular characterization of Pseudomonas aeruginosa from diabetic foot infections in Tunisia. J Med Microbiol 2024; 73. [PMID: 38963417 DOI: 10.1099/jmm.0.001851] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 07/05/2024] Open
Abstract
Background. Pseudomonas aeruginosa is an invasive organism that frequently causes severe tissue damage in diabetic foot ulcers.Gap statement. The characterisation of P. aeruginosa strains isolated from diabetic foot infections has not been carried out in Tunisia.Purpose. The aim was to determine the prevalence of P. aeruginosa isolated from patients with diabetic foot infections (DFIs) in Tunisia and to characterize their resistance, virulence and molecular typing.Methods. Patients with DFIs admitted to the diabetes department of the International Hospital Centre of Tunisia, from September 2019 to April 2021, were included in this prospective study. P. aeruginosa were obtained from the wound swabs, aspiration and soft tissue biopsies during routine clinical care and were confirmed by matrix-assisted laser desorption/ionization time-of-flight mass spectrometry. Antimicrobial susceptibility testing, serotyping, integron and OprD characterization, virulence, biofilm production, pigment quantification, elastase activity and molecular typing were analysed in all recovered P. aeruginosa isolates by phenotypic tests, specific PCRs, sequencing, pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing.Results. Sixteen P. aeruginosa isolates (16.3 %) were recovered from 98 samples of 78 diabetic patients and were classified into 6 serotypes (O:11 the most frequent), 11 different PFGE patterns and 10 sequence types (three of them new ones). The high-risk clone ST235 was found in two isolates. The highest resistance percentages were observed to netilmicin (69 %) and cefepime (43.8 %). Four multidrug-resistant (MDR) isolates (25 %) were detected, three of them being carbapenem-resistant. The ST235-MDR strain harboured the In51 class 1 integron (intI1 +aadA6+orfD+qacED1-sul1). According to the detection of 14 genes involved in virulence or quorum sensing, 5 virulotypes were observed, including 5 exoU-positive, 9 exoS-positive and 2 exoU/exoS-positive strains. The lasR gene was truncated by ISPpu21 insertion sequence in one isolate, and a deletion of 64 bp in the rhlR gene was detected in the ST235-MDR strain. Low biofilm, pyoverdine and elastase production were detected in all P. aeruginosa; however, the lasR-truncated strain showed a chronic infection phenotype characterized by loss of serotype-specific antigenicity, high production of phenazines and high biofilm formation.Conclusions. Our study demonstrated for the first time the prevalence and the molecular characterization of P. aeruginosa strains from DFIs in Tunisia, showing a high genetic diversity, moderate antimicrobial resistance, but a high number of virulence-related traits, highlighting their pathological importance.
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Affiliation(s)
- Ameni Arfaoui
- Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Beatriz Rojo-Bezares
- Área de Microbiología Molecular, Centro de Investigación Biomédica de La Rioja (CIBIR), Logroño, Spain
| | - Meha Fethi
- Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Maria López
- Área de Microbiología Molecular, Centro de Investigación Biomédica de La Rioja (CIBIR), Logroño, Spain
| | - Paula Toledano
- Área de Microbiología Molecular, Centro de Investigación Biomédica de La Rioja (CIBIR), Logroño, Spain
| | - Noureddine Sayem
- Service of Biology, Carthagene International Hospital of Tunisia, Tunis, Tunisia
| | | | - Hadda-Imene Ouzari
- Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Naouel Klibi
- Laboratory of Microorganisms and Active Biomolecules, Faculty of Sciences of Tunis, University of Tunis El Manar, Tunis, Tunisia
| | - Yolanda Sáenz
- Área de Microbiología Molecular, Centro de Investigación Biomédica de La Rioja (CIBIR), Logroño, Spain
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Parolin GA, Vital VG, de Vasconcellos SP, Lago JHG, Péres LO. Thymol as Starting Material for the Development of a Biobased Material with Enhanced Antimicrobial Activity: Synthesis, Characterization, and Potential Application. Molecules 2024; 29:1010. [PMID: 38474522 DOI: 10.3390/molecules29051010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2023] [Revised: 10/19/2023] [Accepted: 10/20/2023] [Indexed: 03/14/2024] Open
Abstract
A biobased material, polythymol (PTF), was prepared using thymol, a monoterpene obtained from the essential oil of Thymus vulgaris (Lamiaceae), as a starting material with the aim of enhancing the antimicrobial properties of this natural product. Initially, different processes were performed in order to optimize the reaction conditions to obtain a macromolecule with a high purity and yield. PTF was characterized using different techniques, such as NMR, infrared, UV-Vis, and thermogravimetric analyses. The antimicrobial activity of both PTF and thymol was evaluated against different microorganisms, including S. aureus, E. coli, P. aeruginosa, and C. albicans. The obtained MIC values showed a higher potential for PTF than the monomer thymol-for example, against S. aureus (500 and 31.5 µg·mL-1 for thymol and PTF, respectively). Therefore, the obtained results show that the polymerization of thymol afforded more active biomaterial than the starting monomeric antimicrobial compound (thymol), suggesting that PTF is an important biomaterial.
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Affiliation(s)
- Giovana A Parolin
- Laboratory of Hybrid Materials, Chemistry Department, Federal University of São Paulo, Diadema 09913-030, SP, Brazil
| | - Vitor G Vital
- Multidisciplinary Laboratory of Health and Environment Sciences, Department of Pharmaceutical Sciences, Federal University of São Paulo, Diadema 09913-030, SP, Brazil
| | - Suzan P de Vasconcellos
- Multidisciplinary Laboratory of Health and Environment Sciences, Department of Pharmaceutical Sciences, Federal University of São Paulo, Diadema 09913-030, SP, Brazil
| | - João Henrique G Lago
- Laboratory of Chemical Biology, Center for Natural and Human Sciences, Federal University of ABC, Santo Andre 09210-580, SP, Brazil
| | - Laura O Péres
- Laboratory of Hybrid Materials, Chemistry Department, Federal University of São Paulo, Diadema 09913-030, SP, Brazil
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Coenye T. Biofilm antimicrobial susceptibility testing: where are we and where could we be going? Clin Microbiol Rev 2023; 36:e0002423. [PMID: 37812003 PMCID: PMC10732061 DOI: 10.1128/cmr.00024-23] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/21/2023] [Accepted: 07/27/2023] [Indexed: 10/10/2023] Open
Abstract
Our knowledge about the fundamental aspects of biofilm biology, including the mechanisms behind the reduced antimicrobial susceptibility of biofilms, has increased drastically over the last decades. However, this knowledge has so far not been translated into major changes in clinical practice. While the biofilm concept is increasingly on the radar of clinical microbiologists, physicians, and healthcare professionals in general, the standardized tools to study biofilms in the clinical microbiology laboratory are still lacking; one area in which this is particularly obvious is that of antimicrobial susceptibility testing (AST). It is generally accepted that the biofilm lifestyle has a tremendous impact on antibiotic susceptibility, yet AST is typically still carried out with planktonic cells. On top of that, the microenvironment at the site of infection is an important driver for microbial physiology and hence susceptibility; but this is poorly reflected in current AST methods. The goal of this review is to provide an overview of the state of the art concerning biofilm AST and highlight the knowledge gaps in this area. Subsequently, potential ways to improve biofilm-based AST will be discussed. Finally, bottlenecks currently preventing the use of biofilm AST in clinical practice, as well as the steps needed to get past these bottlenecks, will be discussed.
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Affiliation(s)
- Tom Coenye
- Laboratory of Pharmaceutical Microbiology, Ghent University, Ghent, Belgium
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Pajavand H, Mobarez AM, Barati A, Nikkhah M, Delnavazi MR, Abiri R, Alvandi AH, Karimiravesh R. Evaluation of combined carbon dots and ciprofloxacin on the expression level of pslA, pelA, and ppyR genes and biofilm production in ciprofloxacin-resistant Pseudomonas aeruginosa isolates from burn wound infection in Iran. J Glob Antimicrob Resist 2023; 35:289-296. [PMID: 37844801 DOI: 10.1016/j.jgar.2023.10.005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2023] [Revised: 09/19/2023] [Accepted: 10/08/2023] [Indexed: 10/18/2023] Open
Abstract
OBJECTIVES Antimicrobial resistance and biofilm formation are increasingly significant public health concerns. This study aimed to examine the antibacterial and antibiofilm properties of carbon dots (C-dots) alone and in combination with antibiotics against biofilm-forming isolates of Pseudomonas aeruginosa. METHODS The antibacterial property of C-dots was investigated by broth microdilution method against ATCC PAO1 and P. aeruginosa clinical isolates. The antibacterial effect of the C-dots and ciprofloxacin combination was investigated using the checkerboard method. The antibiofilm effect of the C-dots alone and its combination with ciprofloxacin was evaluated using the microtiter plate method. Subsequently, the toxicity of each agent was tested on L929 fibroblast cells. In the end, the effects of C-dots on the expression levels of pslA, pelA, and ppyR genes were determined using real-time quantitative PCR. RESULTS The combination of C-dots and ciprofloxacin exhibited a synergistic effect. Additionally, this compound substantially decreased bacterial growth (P < 0.0001) and inhibited biofilm formation at MIC (96 µg/mL) and sub-MIC (48 µg/mL) concentrations (P < 0.0053, P < 0.01). After being exposed to C-dots at a concentration of 1mg/mL for 24 hours, the survival rate of L929 cells was 87.3%. The expression of genes pslA, pelA, and ppyR, associated with biofilm formation in P. aeruginosa, was significantly reduced upon exposure to C-dots (P < 0.0023). CONCLUSIONS The findings demonstrate a promising new treatment method for infections. Furthermore, reducing the dosage of antibiotics can lead to an improvement in the toxic effects caused by dose-dependent antibiotics and antimicrobial activity.
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Affiliation(s)
- Hamid Pajavand
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
| | - Ashraf Mohabti Mobarez
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran.
| | - Ali Barati
- Department of Chemistry, Razi University, Kermanshah, Iran
| | - Maryam Nikkhah
- Department of Nanobiotechnology, Faculty of Biological Sciences, Tarbiat Modares University Tehran, Iran
| | - Mohammad Raza Delnavazi
- Department of Pharmacognosy, Faculty of Pharmacy, Tehran University of Medical Sciences, Tehran, I.R. Iran
| | - Ramin Abiri
- Department of Microbiology, Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Amir Houshang Alvandi
- Department of Microbiology, Faculty of Medicine, Kermanshah University of Medical Sciences, Kermanshah, Iran
| | - Rahleh Karimiravesh
- Department of Bacteriology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran, Iran
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Shakerimoghaddam A, Moghaddam AD, Barghchi B, Pisheh Sanani MG, Azami P, Kalmishi A, Sabeghi P, Motavalli F, Khomartash MS, Mousavi SH, Nikmanesh Y. Prevalence of Pseudomonas aeruginosa and its antibiotic resistance in patients who have received Hematopoietic Stem-Cell Transplantation; A globally Systematic Review. Microb Pathog 2023; 184:106368. [PMID: 37769854 DOI: 10.1016/j.micpath.2023.106368] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2023] [Revised: 09/20/2023] [Accepted: 09/20/2023] [Indexed: 10/03/2023]
Abstract
Gram-negative bacteria are infectious and life-threatening agents after hematopoietic stem cell transplantation (HSCT). So, this study aimed to investigate the prevalence of Pseudomonas aeruginosa and its antibiotic resistance in patients who have received Hematopoietic Stem-Cell Transplantation through a systematic review. The systematic search was done with key words; Pseudomonas aeruginosa, hematopoietic stem cell transplantation from 2000 to the end of July 2023 in Google Scholar and PubMed/Medline, Scopus, and Web of Science. Twelve studies were able to include our study. Quality assessment of studies was done by Appraisal tool for Cross-Sectional Studies. The most of the included studies were conducted as allo-HSCT. Infections such as respiratory infection, urinary infection and bacteremia have occurred. The rate of prevalence with P. aeruginosa has varied between 3 and 100%. The average age of the participants was between 1 and 74 years. The rate of prevalence of P. aeruginosa resistant to several drugs has been reported to be variable, ranging from 20 to 100%. The highest antibiotic resistance was reported against cefotetan (100%), and the lowest was related to tobramycin (1.8%) followed by amikacin, levofloxacin and ciprofloxacin with the prevalence of 16.6%. Our findings showed a high prevalence and antibiotic resistance rate of P. aeruginosa in Hematopoietic stem cell transplantation. Therefore, more serious health measures should be taken in patients after transplantation.
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Affiliation(s)
- Ali Shakerimoghaddam
- Medical Biotechnology Research Center, AJA University of Medical Sciences, Tehran, Iran
| | - Arasb Dabbagh Moghaddam
- Infectious Diseases Research Center, Aja University of Medical Sciences, Tehran, Iran; Department of Public Health & Nutrition, Aja University of Medical Sciences, Tehran, Iran
| | - Bita Barghchi
- Medical School, Islamic Azad University, Tehran, Branch, Tehran, Iran
| | | | - Pouria Azami
- Cardiovascular Research Center, Shiraz University of Medical Sciences, Shiraz, Iran
| | - Abolfazl Kalmishi
- Department of Internal and Surgical Nursing Faculty of Nursing and Midwifery, Sabzevar University of Medical Sciences, Sabzevar, Iran
| | - Paniz Sabeghi
- Medical School, Shiraz University of Medical Sciences, Shiraz Branch, Shiraz, Iran
| | - Farhad Motavalli
- Medical Biotechnology Research Center, AJA University of Medical Sciences, Tehran, Iran
| | | | - Seyyed Hossein Mousavi
- Department of Cardiology, School of Medicine, AJA University of Medical Sciences, Tehran, Iran
| | - Yousef Nikmanesh
- Gastroenterohepatology Research Center, Shiraz University of Medical Sciences, Shiraz, Iran.
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Valadbeigi H, Sadeghifard N, Kaviar VH, Haddadi MH, Ghafourian S, Maleki A. Effect of ZnO nanoparticles on biofilm formation and gene expression of the toxin-antitoxin system in clinical isolates of Pseudomonas aeruginosa. Ann Clin Microbiol Antimicrob 2023; 22:89. [PMID: 37798613 PMCID: PMC10557154 DOI: 10.1186/s12941-023-00639-2] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/24/2023] [Accepted: 09/25/2023] [Indexed: 10/07/2023] Open
Abstract
BACKGROUND Biofilm formation by Pseudomonas aeruginosa (P. aeruginosa) is known to be characteristic of this organism. This bacterium is considered one of the most life-threatening bacteria and has been identified as a priority pathogen for research by WHO. Biofilm-producing P. aeruginosa is a concern in many parts of the world due to antibiotic resistance. Alginate also plays an important role in the biofilm formation of P. aeruginosa as well as the emergence of antibiotic resistance in biofilms. In addition, the systems of toxin-antitoxin( TA) play an important role in biofilm formation. Metal nanoparticle(NP) such as zinc oxide (ZnO) also have extensive biological properties, especially anti-biofilm properties. Therefore, this study was conducted in relation to the importance of zinc oxide nanoparticles (ZnO NPs) in biofilm formation and also the correlation of gene expression of TA systems in clinical isolates of P. aeruginosa. METHODS A total of 52 P. aeruginosa isolates were collected from burns (n = 15), UTI (n = 31), and trachea (n = 6) in hospitals in Ilam between May 2020 and October 2020. Biofilm formation was assessed using a microtiter plate assay. MIC and sub-MIC concentrations of ZnO NPs (10-30 nm with purity greater than 99.8%) in P. aeruginosa were determined. Subsequently, biofilm formation was investigated using sub-MIC concentrations of ZnO NPs. Finally, total RNA was extracted and RT- qPCR was used to determine the expression levels of genes of mazEF, mqsRA, and higBA of TA systems. RESULTS Six isolates of P. aeruginosa were found to form strong biofilms. The results showed that ZnO NPs were able to inhibit biofilm formation. In our experiments, we found that the sub-MIC concentration of ZnO NPs increased the gene expression of antitoxins mazE and mqsA and toxin higB of TA systems treated with ZnO NPs. CONCLUSIONS In the present study, ZnO NPs were shown to effectively inhibit biofilm formation in P. aeruginosa. Our results support the relationship between TA systems and ZnO NPs in biofilm formation in P. aeruginosa. Importantly, the expression of antitoxins mazE and mqsA was high after treatment with ZnO NPs, but not that of antitoxin higA.
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Affiliation(s)
- Hassan Valadbeigi
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran.
| | - Nourkhoda Sadeghifard
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | - Vahab Hassan Kaviar
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
| | | | - Sobhan Ghafourian
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
- Department of Microbiology, School of Medicine, Ilam University of Medical Sciences, Ilam, Iran
| | - Abbas Maleki
- Clinical Microbiology Research Center, Ilam University of Medical Sciences, Ilam, Iran
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Valentin JDP, Altenried S, Varadarajan AR, Ahrens CH, Schreiber F, Webb JS, van der Mei HC, Ren Q. Identification of Potential Antimicrobial Targets of Pseudomonas aeruginosa Biofilms through a Novel Screening Approach. Microbiol Spectr 2023; 11:e0309922. [PMID: 36779712 PMCID: PMC10100978 DOI: 10.1128/spectrum.03099-22] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/08/2022] [Accepted: 01/15/2023] [Indexed: 02/14/2023] Open
Abstract
Pseudomonas aeruginosa is an opportunistic pathogen of considerable medical importance, owing to its pronounced antibiotic tolerance and association with cystic fibrosis and other life-threatening diseases. The aim of this study was to highlight the genes responsible for P. aeruginosa biofilm tolerance to antibiotics and thereby identify potential new targets for the development of drugs against biofilm-related infections. By developing a novel screening approach and utilizing a public P. aeruginosa transposon insertion library, several biofilm-relevant genes were identified. The Pf phage gene (PA0720) and flagellin gene (fliC) conferred biofilm-specific tolerance to gentamicin. Compared with the reference biofilms, the biofilms formed by PA0720 and fliC mutants were completely eliminated with a 4-fold-lower gentamicin concentration. Furthermore, the mreC, pprB, coxC, and PA3785 genes were demonstrated to play major roles in enhancing biofilm tolerance to gentamicin. The analysis of biofilm-relevant genes performed in this study provides important novel insights into the understanding of P. aeruginosa antibiotic tolerance, which will facilitate the detection of antibiotic resistance and the development of antibiofilm strategies against P. aeruginosa. IMPORTANCE Pseudomonas aeruginosa is an opportunistic pathogen of high medical importance and is one of the main pathogens responsible for the mortality of patients with cystic fibrosis. In addition to inherited antibiotic resistance, P. aeruginosa can form biofilms, defined as communities of microorganisms embedded in a self-produced matrix of extracellular polymeric substances adhering to each other and/or to a surface. Biofilms protect bacteria from antibiotic treatments and represent a major reason for antibiotic failure in the treatment of chronic infections caused by cystic fibrosis. Therefore, it is crucial to develop new therapeutic strategies aimed at specifically eradicating biofilms. The aim of this study was to generalize a novel screening method for biofilm research and to identify the possible genes involved in P. aeruginosa biofilm tolerance to antibiotics, both of which could improve the understanding of biofilm-related infections and allow for the identification of relevant therapeutic targets for drug development.
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Affiliation(s)
- Jules D. P. Valentin
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
- University of Groningen and University Medical Center Groningen, Department of BioMedical Engineering, Groningen, Netherlands
| | - Stefanie Altenried
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
| | - Adithi R. Varadarajan
- Molecular Ecology, Agroscope and Swiss Institute of Bioinformatics, Zurich, Switzerland
| | - Christian H. Ahrens
- Molecular Ecology, Agroscope and Swiss Institute of Bioinformatics, Zurich, Switzerland
| | - Frank Schreiber
- Division of Biodeterioration and Reference Organisms (4.1), Department of Materials and the Environment, Federal Institute for Materials Research and Testing (BAM), Berlin, Germany
| | - Jeremy S. Webb
- Institute for Life Sciences, University of Southampton, Southampton, United Kingdom
- National Biofilms Innovation Centre, University of Southampton, Southampton, United Kingdom
| | - Henny C. van der Mei
- University of Groningen and University Medical Center Groningen, Department of BioMedical Engineering, Groningen, Netherlands
| | - Qun Ren
- Laboratory for Biointerfaces, Empa, Swiss Federal Laboratories for Materials Science and Technology, St. Gallen, Switzerland
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Mohamed HMA, Alnasser SM, Abd-Elhafeez HH, Alotaibi M, Batiha GES, Younis W. Detection of β-Lactamase Resistance and Biofilm Genes in Pseudomonas Species Isolated from Chickens. Microorganisms 2022; 10:microorganisms10101975. [PMID: 36296251 PMCID: PMC9611058 DOI: 10.3390/microorganisms10101975] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/12/2022] [Revised: 09/26/2022] [Accepted: 09/30/2022] [Indexed: 11/16/2022] Open
Abstract
Bacteria of the genus Pseudomonas are pathogens in both humans and animals. The most prevalent nosocomial pathogen is P. aeruginosa, particularly strains with elevated antibiotic resistance. In this study, a total of eighteen previously identified Pseudomonas species strains, were isolated from chicken. These strains were screened for biofilm formation and antibiotic resistance. In addition, we evaluated clove oil’s effectiveness against Pseudomonas isolates as an antibiofilm agent. The results showed that Pseudomonas species isolates were resistant to most antibiotics tested, particularly those from the β-lactamase family. A significant correlation (p < 0.05) between the development of multidrug-resistant isolates and biofilms is too informal. After amplifying the AmpC-plasmid-mediated genes (blaCMY, blaMIR, DHA, and FOX) and biofilm-related genes (psld, rhlA, and pelA) in most of our isolates, PCR confirmed this relationship. Clove oil has a potent antibiofilm effect against Pseudomonas isolates, and may provide a treatment for bacteria that form biofilms and are resistant to antimicrobials.
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Affiliation(s)
- Hams M. A. Mohamed
- Department of Microbiology, Faculty of Veterinary Medicine, South Valley University, Qena 83523, Egypt
- Correspondence: (H.M.A.M.); (S.M.A.); (H.H.A.-E.)
| | - Sulaiman Mohammed Alnasser
- Department of Pharmacology and Toxicology, Unaizah College of Pharmacy, Qassim University, Buraydah 52571, Saudi Arabia
- Correspondence: (H.M.A.M.); (S.M.A.); (H.H.A.-E.)
| | - Hanan H. Abd-Elhafeez
- Department of Cells and Tissues, Faculty of Veterinary Medicine, Assiut University, Assiut 71526, Egypt
- Correspondence: (H.M.A.M.); (S.M.A.); (H.H.A.-E.)
| | - Meshal Alotaibi
- Department of Pharmacy Practice, College of Pharmacy, University of Hafr Albatin, Hafr Albatin 39524, Saudi Arabia
| | - Gaber El-Saber Batiha
- Department of Pharmacology and Therapeutics, Faculty of Veterinary Medicine, Damanhur University, Damanhur 22511, Egypt
| | - Waleed Younis
- Department of Microbiology, Faculty of Veterinary Medicine, South Valley University, Qena 83523, Egypt
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Antibiofilm Properties of Antiseptic Agents Used on Pseudomonas aeruginosa Isolated from Diabetic Foot Ulcers. Int J Mol Sci 2022; 23:ijms231911270. [PMID: 36232569 PMCID: PMC9569737 DOI: 10.3390/ijms231911270] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Revised: 09/11/2022] [Accepted: 09/13/2022] [Indexed: 11/16/2022] Open
Abstract
In diabetic foot ulcers (DFUs), biofilm formation is a major challenge that promotes wound chronicity and delays healing. Antiseptics have been proposed to combat biofilms in the management of DFUs. However, there is limited evidence on the activity of these agents against biofilms, and there are questions as to which agents have the best efficiency. Here, we evaluated the antibiofilm activity of sodium hypochlorite, polyvinylpyrrolidoneIodine (PVPI), polyhexamethylenebiguanide (PHMB) and octenidine against Pseudomonas aeruginosa strains using static and dynamic systems in a chronic-wound-like medium (CWM) that mimics the chronic wound environment. Using Antibiofilmogram®, a technology assessing the ability of antiseptics to reduce the initial phase of biofilm formation, we observed the significant activity of antiseptics against biofilm formation by P. aeruginosa (at 1:40 to 1:8 dilutions). Moreover, 1:100 to 1:3 dilutions of the different antiseptics reduced mature biofilms formed after 72 h by 10-log, although higher concentrations were needed in CWM (1:40 to 1:2). Finally, in the BioFlux200TM model, after biofilm debridement, sodium hypochlorite and PHMB were the most effective antiseptics. In conclusion, our study showed that among the four antiseptics tested, sodium hypochlorite demonstrated the best antibiofilm activity against P. aeruginosa biofilms and represents an alternative in the management of DFUs.
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Wu RT, Chen JY, Liu S, Niu SH, Liao XD, Xing SC. Cyclic AMP and biofilms reveal the synergistic proliferation strategy of Pseudomonas aeruginosa and Escherichia coli under the costimulation of high concentrations of microplastics and enrofloxacin. THE SCIENCE OF THE TOTAL ENVIRONMENT 2022; 838:156470. [PMID: 35660582 DOI: 10.1016/j.scitotenv.2022.156470] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/28/2022] [Revised: 05/28/2022] [Accepted: 05/31/2022] [Indexed: 06/15/2023]
Abstract
Microplastics (MPs) provide attachment sites for biofilm formation of microorganisms, which can promote their resistance to environmental stress has been proved. However, the effect of MPs on synergy survival among microorganisms under antibiotic stress remains unclear. In the present study, the proliferation of Escherichia coli and Pseudomonas aeruginosa was assessed under enrofloxacin stress with the influence of MPs. Here, MPs reduced the growth speed of E. coli and enhanced that of P. aeruginosa, especially at 12 h, but the final value of OD600 and CFU of both bacteria not be influenced. E. coli was enrofloxacin sensitive (MIC = 0.25 μg/mL), and a high MP concentration in the presence of enrofloxacin notably enhanced the biofilm formation ability of P. aeruginosa, but proliferation decreased. In the coculture system, the proliferation of E. coli (increased 1.42-fold) and P. aeruginosa (increased 1.06-fold) both increased under enrofloxacin stress (0.25 μg/mL) with high-concentration MP addition. P. aeruginosa may provide the biofilm matrix for E. coli to resist the stress of enrofloxacin. The high concentration of cyclic AMP secreted by E. coli may slightly inhibited biofilm formation, leading to a decrease in the fitness cost of P. aeruginosa; thus, the proliferation of P. aeruginosa increased. The present study is the first to show that MP combined with antibiotics stimulates the metabolic cooperation of bacteria to promote proliferation.
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Affiliation(s)
- Rui-Ting Wu
- College of Animal Science, South China Agricultural University, Guangzhou 510642, Guangdong, China
| | - Jing-Yuan Chen
- College of Animal Science, South China Agricultural University, Guangzhou 510642, Guangdong, China
| | - Shuo Liu
- College of Animal Science, South China Agricultural University, Guangzhou 510642, Guangdong, China
| | - Shi-Hua Niu
- College of Animal Science, South China Agricultural University, Guangzhou 510642, Guangdong, China
| | - Xin-Di Liao
- College of Animal Science, South China Agricultural University, Guangzhou 510642, Guangdong, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry Agriculture, Guangzhou, 510642, Guangdong, China; National-Local Joint Engineering Research Center for Livestock Breeding, Guangzhou, 510642, Guangdong, China
| | - Si-Cheng Xing
- Integrative Microbiology Research Centre, South China Agricultural University, Guangzhou 510642, China; College of Animal Science, South China Agricultural University, Guangzhou 510642, Guangdong, China; Guangdong Provincial Key Lab of Agro-Animal Genomics and Molecular Breeding, Key Laboratory of Chicken Genetics, Breeding and Reproduction, Ministry Agriculture, Guangzhou, 510642, Guangdong, China; National-Local Joint Engineering Research Center for Livestock Breeding, Guangzhou, 510642, Guangdong, China.
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Relationship between Biofilm-Formation, Phenotypic Virulence Factors and Antibiotic Resistance in Environmental Pseudomonas aeruginosa. Pathogens 2022; 11:pathogens11091015. [PMID: 36145447 PMCID: PMC9503712 DOI: 10.3390/pathogens11091015] [Citation(s) in RCA: 9] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/24/2022] [Revised: 09/01/2022] [Accepted: 09/02/2022] [Indexed: 11/17/2022] Open
Abstract
The formation of a protective biofilm by Pseudomonas aeruginosa (PA) is one of the hallmarks of their survival both in vivo and in harsh environmental conditions, thus, biofilm-eradication has relevance from therapeutic perspectives and for infection control. The aim of our study was to investigate the possible relationship between antibiotic resistance, biofilm-forming capacity and virulence factors in n = 166 PA isolates of environmental origin. Antimicrobial susceptibility testing and the phenotypic detection of resistance determinants were carried out using standard protocols. The biofilm-forming capacity of PA was tested using a standardized crystal violet microtiter plate-based method. Motility (swimming, swarming, and twitching) and siderophore production of the isolates were also assessed. Resistance rates were highest for ciprofloxacin (46.98%), levofloxacin (45.18%), ceftazidime (31.92%) and cefepime (30.12%); 19.28% of isolates met the criteria to be classified as multidrug-resistant (MDR). Efflux pump overexpression, AmpC overexpression, and modified Hodge-test positivity were noted in 28.31%, 18.07% and 3.61%, respectively. 22.89% of isolates were weak/non-biofilm producers, while 27.71% and 49.40% were moderate and strong biofilm producers, respectively. Based on MDR status of the isolates, no significant differences in biofilm-production were shown among environmental PA (non-MDR OD570 [mean ± SD]: 0.416 ± 0.167 vs. MDR OD570: 0.399 ± 0.192; p > 0.05). No significant association was observed between either motility types in the context of drug resistance or biofilm-forming capacity (p > 0.05). 83.13% of isolates tested were positive for siderophore production. The importance of PA as a pathogen in chronic and healthcare-associated infections has been described extensively, while there is increasing awareness of PA as an environmental agent in agriculture and aquaculture. Additional studies in this field would be an important undertaking to understand the interrelated nature of biofilm production and antimicrobial resistance, as these insights may become relevant bases for developing novel therapeutics and eradication strategies against PA.
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Dey A, Yadav M, Kumar D, Dey AK, Samal S, Tanwar S, Sarkar D, Pramanik SK, Chaudhuri S, Das A. A combination therapy strategy for treating antibiotic resistant biofilm infection using a guanidinium derivative and nanoparticulate Ag(0) derived hybrid gel conjugate. Chem Sci 2022; 13:10103-10118. [PMID: 36128224 PMCID: PMC9430544 DOI: 10.1039/d2sc02980d] [Citation(s) in RCA: 11] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2022] [Accepted: 07/22/2022] [Indexed: 11/25/2022] Open
Abstract
Bacteria organized in biofilms show significant tolerance to conventional antibiotics compared to their planktonic counterparts and form the basis for chronic infections. Biofilms are composites of different types of extracellular polymeric substances that help in resisting several host-defense measures, including phagocytosis. These are increasingly being recognized as a passive virulence factor that enables many infectious diseases to proliferate and an essential contributing facet to anti-microbial resistance. Thus, inhibition and dispersion of biofilms are linked to addressing the issues associated with therapeutic challenges imposed by biofilms. This report is to address this complex issue using a self-assembled guanidinium-Ag(0) nanoparticle (AD-L@Ag(0)) hybrid gel composite for executing a combination therapy strategy for six difficult to treat biofilm-forming and multidrug-resistant bacteria. Improved efficacy was achieved primarily through effective biofilm inhibition and dispersion by the cationic guanidinium ion derivative, while Ag(0) contributes to the subsequent bactericidal activity on planktonic bacteria. Minimum Inhibitory Concentration (MIC) of the AD-L@Ag(0) formulation was tested against Acinetobacter baumannii (25 μg mL-1), Pseudomonas aeruginosa (0.78 μg mL-1), Staphylococcus aureus (0.19 μg mL-1), Klebsiella pneumoniae (0.78 μg mL-1), Escherichia coli (clinical isolate (6.25 μg mL-1)), Klebsiella pneumoniae (clinical isolate (50 μg mL-1)), Shigella flexneri (clinical isolate (0.39 μg mL-1)) and Streptococcus pneumoniae (6.25 μg mL-1). Minimum bactericidal concentration, and MBIC50 and MBIC90 (Minimum Biofilm Inhibitory Concentration at 50% and 90% reduction, respectively) were evaluated for these pathogens. All these results confirmed the efficacy of the formulation AD-L@Ag(0). Minimum Biofilm Eradication Concentration (MBEC) for the respective pathogens was examined by following the exopolysaccharide quantification method to establish its potency in inhibition of biofilm formation, as well as eradication of mature biofilms. These effects were attributed to the bactericidal effect of AD-L@Ag(0) on biofilm mass-associated bacteria. The observed efficacy of this non-cytotoxic therapeutic combination (AD-L@Ag(0)) was found to be better than that reported in the existing literature for treating extremely drug-resistant bacterial strains, as well as for reducing the bacterial infection load at a surgical site in a small animal BALB/c model. Thus, AD-L@Ag(0) could be a promising candidate for anti-microbial coatings on surgical instruments, wound dressing, tissue engineering, and medical implants.
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Affiliation(s)
- Ananta Dey
- CSIR - Central Salt and Marine Chemical Research Institute Bhavnagar Gujarat India
- Indian Institute of Science Education and Research Kolkata Mohanpur 741246 West Bengal India
| | - Manisha Yadav
- Translational Health Science and Technology Institute (THSTI) Faridabad 121001 Haryana India
| | - Deepak Kumar
- Translational Health Science and Technology Institute (THSTI) Faridabad 121001 Haryana India
| | - Anik Kumar Dey
- CSIR - Central Salt and Marine Chemical Research Institute Bhavnagar Gujarat India
| | - Sweety Samal
- Translational Health Science and Technology Institute (THSTI) Faridabad 121001 Haryana India
| | - Subhash Tanwar
- Translational Health Science and Technology Institute (THSTI) Faridabad 121001 Haryana India
| | - Debrupa Sarkar
- Translational Health Science and Technology Institute (THSTI) Faridabad 121001 Haryana India
| | - Sumit Kumar Pramanik
- CSIR - Central Salt and Marine Chemical Research Institute Bhavnagar Gujarat India
| | - Susmita Chaudhuri
- Translational Health Science and Technology Institute (THSTI) Faridabad 121001 Haryana India
| | - Amitava Das
- Indian Institute of Science Education and Research Kolkata Mohanpur 741246 West Bengal India
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13
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Heidari R, Farajzadeh Sheikh A, Hashemzadeh M, Farshadzadeh Z, Salmanzadeh S, Saki M. Antibiotic resistance, biofilm production ability and genetic diversity of carbapenem-resistant Pseudomonas aeruginosa strains isolated from nosocomial infections in southwestern Iran. Mol Biol Rep 2022; 49:3811-3822. [PMID: 35169997 PMCID: PMC8853202 DOI: 10.1007/s11033-022-07225-3] [Citation(s) in RCA: 20] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2021] [Accepted: 02/02/2022] [Indexed: 12/14/2022]
Abstract
Background This study was aimed to evaluate the antibiotic resistance, biofilm formation, and genetic diversity of carbapenem-resistant Pseudomonas aeruginosa (CRPA) strains isolated from four types of nosocomial infections (NIs) including urinary tract infection (UTI), ventilator-associated pneumonia (VAP), surgical site infection (SSI), and bloodstream infection (BSI). Methods and results In total, 115 isolates of NIs-causing P. aeruginosa were collected from NIs. Antibiotic susceptibility testing (AST) was performed using disk diffusion method and minimum inhibitory concentrations. Biofilm formation was tested on 96-well polystyrene microtiter plates (MTP). CRPA isolates were genotyped using multiple-locus variable number of tandem repeat analysis (MLVA). The most resistance and susceptibility rates were observed to amikacin (70.6%) and colistin (96.1%), respectively. Colistin and meropenem were the most active antimicrobial agents in VAP, SSI, and BSI. While, colistin and cefepime were the most active in UTIs. In total, 52.2% (n = 60/115) of P. aeruginosa isolates were carbapenem resistant, of which 95.0%, 55.0%, and 5.0% were multidrug-resistant, extensively drug-resistant, and pandrug-resistant, respectively. There was a significant association between resistance to carbapenem and resistance to other antibiotics except for piperacillin/tazobactam. The biofilm production of CRPA isolates was 95.0%, of which 23.3% were strong biofilm producers. Based on MLVA, there were 34 different types of CRPA isolates classified into three main clusters and 5 sub clusters. Conclusion The association of CRPA with other antibiotic resistance, the high rates of biofilm production, and the high genetic diversity of the isolates may be a warning of the need for a careful surveillance program.
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Affiliation(s)
- Reza Heidari
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Ahmad Farajzadeh Sheikh
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran.
| | - Mohammad Hashemzadeh
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Zahra Farshadzadeh
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Shokrollah Salmanzadeh
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
- Tropical Medicine Ward, Razi Teaching Hospital, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
| | - Morteza Saki
- Infectious and Tropical Diseases Research Center, Health Research Institute, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
- Department of Microbiology, Faculty of Medicine, Ahvaz Jundishapur University of Medical Sciences, Ahvaz, Iran
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β-lactam Resistance in Pseudomonas aeruginosa: Current Status, Future Prospects. Pathogens 2021; 10:pathogens10121638. [PMID: 34959593 PMCID: PMC8706265 DOI: 10.3390/pathogens10121638] [Citation(s) in RCA: 47] [Impact Index Per Article: 15.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/02/2021] [Revised: 12/06/2021] [Accepted: 12/16/2021] [Indexed: 12/12/2022] Open
Abstract
Pseudomonas aeruginosa is a major opportunistic pathogen, causing a wide range of acute and chronic infections. β-lactam antibiotics including penicillins, carbapenems, monobactams, and cephalosporins play a key role in the treatment of P. aeruginosa infections. However, a significant number of isolates of these bacteria are resistant to β-lactams, complicating treatment of infections and leading to worse outcomes for patients. In this review, we summarize studies demonstrating the health and economic impacts associated with β-lactam-resistant P. aeruginosa. We then describe how β-lactams bind to and inhibit P. aeruginosa penicillin-binding proteins that are required for synthesis and remodelling of peptidoglycan. Resistance to β-lactams is multifactorial and can involve changes to a key target protein, penicillin-binding protein 3, that is essential for cell division; reduced uptake or increased efflux of β-lactams; degradation of β-lactam antibiotics by increased expression or altered substrate specificity of an AmpC β-lactamase, or by the acquisition of β-lactamases through horizontal gene transfer; and changes to biofilm formation and metabolism. The current understanding of these mechanisms is discussed. Lastly, important knowledge gaps are identified, and possible strategies for enhancing the effectiveness of β-lactam antibiotics in treating P. aeruginosa infections are considered.
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Gajdács M, Baráth Z, Kárpáti K, Szabó D, Usai D, Zanetti S, Donadu MG. No Correlation between Biofilm Formation, Virulence Factors, and Antibiotic Resistance in Pseudomonas aeruginosa: Results from a Laboratory-Based In Vitro Study. Antibiotics (Basel) 2021; 10:1134. [PMID: 34572716 PMCID: PMC8471826 DOI: 10.3390/antibiotics10091134] [Citation(s) in RCA: 25] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2021] [Revised: 09/17/2021] [Accepted: 09/19/2021] [Indexed: 12/25/2022] Open
Abstract
Pseudomonas aeruginosa (P. aeruginosa) possesses a plethora of virulence determinants, including the production of biofilm, pigments, exotoxins, proteases, flagella, and secretion systems. The aim of our present study was to establish the relationship between biofilm-forming capacity, the expression of some important virulence factors, and the multidrug-resistant (MDR) phenotype in P. aeruginosa. A total of three hundred and two (n = 302) isolates were included in this study. Antimicrobial susceptibility testing and phenotypic detection of resistance determinants were carried out; based on these results, isolates were grouped into distinct resistotypes and multiple antibiotic resistance (MAR) indices were calculated. The capacity of isolates to produce biofilm was assessed using a crystal violet microtiter-plate based method. Motility (swimming, swarming, and twitching) and pigment-production (pyoverdine and pyocyanin) were also measured. Pearson correlation coefficients (r) were calculated to determine for antimicrobial resistance, biofilm-formation, and expression of other virulence factors. Resistance rates were the highest for ceftazidime (56.95%; n = 172), levofloxacin (54.97%; n = 166), and ciprofloxacin (54.64%; n = 159), while lowest for colistin (1.66%; n = 5); 44.04% (n = 133) of isolates were classified as MDR. 19.87% (n = 60), 20.86% (n = 63) and 59.27% (n = 179) were classified as weak, moderate, and strong biofilm producers, respectively. With the exception of pyocyanin production (0.371 ± 0.193 vs. non-MDR: 0.319 ± 0.191; p = 0.018), MDR and non-MDR isolates did not show significant differences in expression of virulence factors. Additionally, no relevant correlations were seen between the rate of biofilm formation, pigment production, or motility. Data on interplay between the presence and mechanisms of drug resistance with those of biofilm formation and virulence is crucial to address chronic bacterial infections and to provide strategies for their management.
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Affiliation(s)
- Márió Gajdács
- Department of Oral Biology and Experimental Dental Research, Faculty of Dentistry, University of Szeged, Tisza Lajos körút 63, 6720 Szeged, Hungary
- Institute of Medical Microbiology, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, 1089 Budapest, Hungary;
| | - Zoltán Baráth
- Department of Prosthodontics, Faculty of Dentistry, University of Szeged, Tisza Lajos körút 62–64, 6720 Szeged, Hungary;
| | - Krisztina Kárpáti
- Department of Orthodontics and Pediatric Dentistry, Faculty of Dentistry, University of Szeged, Tisza Lajos körút 62–64, 6720 Szeged, Hungary;
| | - Dóra Szabó
- Institute of Medical Microbiology, Faculty of Medicine, Semmelweis University, Nagyvárad tér 4, 1089 Budapest, Hungary;
| | - Donatella Usai
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (D.U.); (S.Z.); (M.G.D.)
| | - Stefania Zanetti
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (D.U.); (S.Z.); (M.G.D.)
| | - Matthew Gavino Donadu
- Department of Biomedical Sciences, University of Sassari, 07100 Sassari, Italy; (D.U.); (S.Z.); (M.G.D.)
- Department of Chemistry and Pharmacy, University of Sassari, 07100 Sassari, Italy
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