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Yousefi L, Kadkhoda H, Shirmohammadi M, Moaddab SY, Ghotaslou R, Tahereh pirzadeh, Sadeghi J, Somi MH, Ahangarzadeh Rezaee M, Ganbarov K, Samadi Kafil H. CRISPR-like sequences association with antibiotic resistance and biofilm formation in Helicobacter pylori clinical isolates. Heliyon 2024; 10:e26809. [PMID: 38449645 PMCID: PMC10915373 DOI: 10.1016/j.heliyon.2024.e26809] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2023] [Revised: 01/31/2024] [Accepted: 02/20/2024] [Indexed: 03/08/2024] Open
Abstract
Role of clustered regularly interspaced short palindromic repeats (CRISPR)-like sequences in antibiotic resistance and biofilm formation isn't clear. This study investigated association of CRISPR-like sequences with antibiotic resistance and biofilm formation in H. pylori isolates. Thirty-six of H. pylori isolates were studied for existence of CRISPR-like sequences using PCR method and their correlation with biofilm formation and antibiotic resistance. Microtiter-plate technique was utilized for investigating antibiotic resistance profile of isolates against amoxicillin, tetracycline, metronidazole and clarithromycin. Biofilm formation of isolates was analyzed by microtiter-plate-based-method. Out of 23 CRISPR-like positive isolates, 19 had ability of biofilm formation and 7 of 13 CRISPR-like negative isolates were able to form biofilm (Pvalue = 0.445). In CRISPR-like positive isolates, 11 (48%), 18 (78%), 18 (78%) and 23 (100%) were resistant to amoxicillin, tetracycline, metronidazole and clarithromycin, respectively. Since CRISPR-like sequences have role in antibiotic resistance, may be applied as genetic markers of antibiotic resistance. But there was no substantial correlation between biofilm formation and existence of CRISPR-like sequences. These results indicate possible importance of CRISPR-like sequences on acquisition of resistance to antibiotics in this bacterium.
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Affiliation(s)
- Leila Yousefi
- Student Research Committee, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Hiva Kadkhoda
- Drug Applied Research center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Masoud Shirmohammadi
- Liver and Gastrointestinal Diseases Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Seyyed Yaghoub Moaddab
- Liver and Gastrointestinal Diseases Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Reza Ghotaslou
- Drug Applied Research center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Tahereh pirzadeh
- Stem Cell Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Javid Sadeghi
- Drug Applied Research center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | - Mohammad Hossein Somi
- Liver and Gastrointestinal Diseases Research Center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
| | | | - Khudaverdi Ganbarov
- Research Laboratory of Microbiology and Virology, Baku State University, Z. Khalilov str., 23 AZ1148, Baku, Azerbaijan
| | - Hossein Samadi Kafil
- Drug Applied Research center, Faculty of Medicine, Tabriz University of Medical Sciences, Tabriz, Iran
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Guidone GHM, Cardozo JG, Silva LC, Sanches MS, Galhardi LCF, Kobayashi RKT, Vespero EC, Rocha SPD. Epidemiology and characterization of Providencia stuartii isolated from hospitalized patients in southern Brazil: a possible emerging pathogen. Access Microbiol 2023; 5:000652.v4. [PMID: 37970084 PMCID: PMC10634494 DOI: 10.1099/acmi.0.000652.v4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2023] [Accepted: 10/08/2023] [Indexed: 11/17/2023] Open
Abstract
This study aimed to characterize the virulence factors and antimicrobial resistance of Providencia stuartii , an opportunistic pathogen that causes human infections. We examined 45 isolates of P. stuartii both genotypically and phenotypically by studying their adherence to HeLa cells, biofilm formation, cytotoxicity and antimicrobial resistance, and analysed their genomes for putative virulence and resistance genes. This study found that most isolates possessed multiple virulence genes, including fimA, mrkA, fptA, iutA, ireA and hlyA, and were cytotoxic to Vero cells. All the isolates were resistant to amoxicillin plus clavulanic acid, levofloxacin and sulfamethoxazole plus trimethoprim, and most were resistant to ceftriaxone and cefepime. All isolates harboured extended-spectrum beta-lactamase coding genes such as bla CTX-M-2 and 23/45(51.11 %) of them also harboured bla CTX-M-9. The gene KPC-2 (carbapenemase) was detected in 8/45(17.77 %) isolates. This study also found clonality among the isolates, indicating the possible spread of the pathogen among patients at the hospital. These results have significant clinical and epidemiological implications and emphasize the importance of a continued understanding of the virulence and antimicrobial resistance of this pathogen for the prevention and treatment of future infections.
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Affiliation(s)
| | - Jennifer Germiniani Cardozo
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina, Brazil
| | - Luana Carvalho Silva
- Laboratory of Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina, Brazil
| | - Matheus Silva Sanches
- Laboratory of Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina, Brazil
| | - Ligia Carla Faccin Galhardi
- Virology Laboratory, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina, Brazil
| | - Renata Katsuko Takayama Kobayashi
- Laboratory of Basic and Applied Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina, Brazil
| | - Eliana Carolina Vespero
- Department of Pathology, Clinical and Toxicological Analysis, Health Sciences Center, University Hospital of Londrina, State University of Londrina, Paraná, Brazil
| | - Sergio Paulo Dejato Rocha
- Laboratory of Bacteriology, Department of Microbiology, Center of Biological Sciences, State University of Londrina, Londrina, Brazil
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Bianchini Fulindi R, Domingues Rodrigues J, Lemos Barbosa TW, Goncalves Garcia AD, de Almeida La Porta F, Pratavieira S, Chiavacci LA, Pessoa Araújo Junior J, da Costa PI, Martinez LR. Zinc-Based Nanoparticles Reduce Bacterial Biofilm Formation. Microbiol Spectr 2023; 11:e0483122. [PMID: 36853055 PMCID: PMC10101090 DOI: 10.1128/spectrum.04831-22] [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: 11/23/2022] [Accepted: 02/01/2023] [Indexed: 03/01/2023] Open
Abstract
Biofilm formation is important for microbial survival in hostile environments and a phenotype that provides microorganisms with antimicrobial resistance. Zinc oxide (ZnO) and Zinc sulfide (ZnS) nanoparticles (NPs) present potential antimicrobial properties for biomedical and food industry applications. Here, we aimed to analyze, for the first time, the bactericidal and antibiofilm activity of ZnS NPs against Staphylococcus aureus, Klebsiella oxytoca, and Pseudomonas aeruginosa, all medically important bacteria in developed countries. We compared ZnS NPs antimicrobial activity to ZnO NPs, which have been extensively studied. Using the colorimetric XTT reduction assay to observe the metabolic activity of bacterial cells and the crystal violet assay to measure biofilm mass, we demonstrated that ZnS and ZnO had similar efficacy in killing planktonic bacterial cells and reducing biofilm formation, with S. aureus being more susceptible to both therapeutics than K. oxytoca and P. aeruginosa. Crystal violet staining and confocal microscopy validated that Zn NPs inhibit biofilm formation and cause architectural damage. Our findings provide proof of principle that ZnS NPs have antibiofilm activity, and can be potentially used in medical and food industry applications, such as treatment of wound infections or package coating for food preservation. IMPORTANCE Zinc (Zn)-based nanoparticles (NPs) can be potentially used in medical and food preservation applications. As proof of principle, we investigated the bactericidal and antibiofilm activity of zinc oxide (ZnO) and zinc sulfide (ZnS) NPs against medically important bacteria. Zn-based NPs were similarly effective in killing planktonic and biofilm-associated Staphylococcus aureus, Klebsiella oxytoca, and Pseudomonas aeruginosa cells. However, S. aureus was more susceptible to these investigational therapeutics. Although further studies are warranted, our findings suggest the possibility of future use of Zn-based NPs in the treatment of skin infections or preservation of food.
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Affiliation(s)
- Rafael Bianchini Fulindi
- Departments of Clinical Analysis, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil
| | | | - Thulio Wliandon Lemos Barbosa
- Departments of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil
| | | | | | - Sebastião Pratavieira
- São Carlos Physics Department, University of São Paulo, São Carlos, São Paulo, Brazil
| | - Leila Aparecida Chiavacci
- Departments of Drugs and Medicines, School of Pharmaceutical Sciences, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil
| | | | - Paulo Inácio da Costa
- Departments of Clinical Analysis, São Paulo State University (UNESP), Araraquara, São Paulo, Brazil
| | - Luis R. Martinez
- Department of Oral Biology, University of Florida College of Dentistry, Gainesville, Florida, USA
- Emerging Pathogens Institute, University of Florida, Gainesville, Florida, USA
- Center for Immunology and Transplantation, University of Florida, Gainesville, Florida, USA
- Center for Translational Research in Neurodegenerative Disease, University of Florida, Gainesville, Florida, USA
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Silva SMDA, Ramos BA, Sá RAQCDE, Silva MVDA, Correia MTS, Oliveira MBMDE. Investigation of factors related to biofilm formation in Providencia stuartii. AN ACAD BRAS CIENC 2022; 94:e20210765. [PMID: 36074405 DOI: 10.1590/0001-3765202220210765] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/26/2021] [Accepted: 11/18/2021] [Indexed: 11/22/2022] Open
Abstract
Providencia stuartii is one of the Enterobacteriaceae species of medical importance commonly associated with urinary infections, which can also cause other ones, including uncommon ones, such as liver abscess and septic vasculitis. This bacterium stands out in the expression of intrinsic and acquired resistance to antimicrobials. Besides, it uses mechanisms such as biofilm for its persistence in biotic and abiotic environments. This study investigated the cellular hydrophobicity profile of clinical isolates of P. stuartii. It also analyzed genes related to the fimbrial adhesin in this species comparing with other reports described for other bacteria from Enterobacteriaceae family. The investigated isolates to form biofilm and had a practically hydrophilic cell surface profile. However, fimH and mrkD genes were not found in P. stuartii, unlike observed in other species of Enterobacteriaceae. These results show that P. stuartii has specificities regarding its potential for biofilm formation, which makes it difficult to destabilize the infectious process and increases the permanence of this pathogen in hospital units.
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Affiliation(s)
- Sivoneide M DA Silva
- Universidade Federal de Pernambuco, Centro de Biociências, Departamento de Bioquímica, Av. Prof. Moraes Rego, 1235, Cidade Universitária, 50670-901 Recife, PE, Brazil
| | - Bárbara A Ramos
- Universidade Federal de Pernambuco, Centro de Biociências, Departamento de Bioquímica, Av. Prof. Moraes Rego, 1235, Cidade Universitária, 50670-901 Recife, PE, Brazil
| | - Rafael A Q C DE Sá
- Universidade Federal de Pernambuco, Centro de Biociências, Departamento de Bioquímica, Av. Prof. Moraes Rego, 1235, Cidade Universitária, 50670-901 Recife, PE, Brazil
| | - Márcia V DA Silva
- Universidade Federal de Pernambuco, Centro de Biociências, Departamento de Bioquímica, Av. Prof. Moraes Rego, 1235, Cidade Universitária, 50670-901 Recife, PE, Brazil
| | - Maria T S Correia
- Universidade Federal de Pernambuco, Centro de Biociências, Departamento de Bioquímica, Av. Prof. Moraes Rego, 1235, Cidade Universitária, 50670-901 Recife, PE, Brazil
| | - Maria B M DE Oliveira
- Universidade Federal de Pernambuco, Centro de Biociências, Departamento de Bioquímica, Av. Prof. Moraes Rego, 1235, Cidade Universitária, 50670-901 Recife, PE, Brazil
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Manandhar S, Nguyen Q, Pham DT, Amatya P, Rabaa M, Dongol S, Basnyat B, Dixit SM, Baker S, Karkey A. A fatal outbreak of neonatal sepsis caused by mcr-10 carrying Enterobacter kobei in a tertiary care hospital in Nepal. J Hosp Infect 2022; 125:60-66. [PMID: 35460799 DOI: 10.1016/j.jhin.2022.03.015] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/13/2022] [Revised: 03/03/2022] [Accepted: 03/23/2022] [Indexed: 11/30/2022]
Abstract
BACKGROUND Enterobacter kobei is an emerging cause of outbreak of nosocomial infections in neonatal intensive care units (NICUs). Between July and September of 2016, an NICU in a tertiary care hospital of Nepal observed an abrupt increase in the number of neonatal sepsis cases caused by Enterobacter spp. infecting 11 of 23 admitted neonates, 5 of whom died of an exacerbated sepsis. AIM Main aims of this study were to confirm the suspected outbreak, identify environmental source of infection, and characterize genetic determinants of antimicrobial resistance (AMR) and virulence of the pathogen. METHODS We performed whole genome sequencing of all Enterobacter spp. isolated from blood cultures of septic neonates admitted to NICU between May 2016 and December 2017. Also, an environmental sampling was intensified from fortnightly to weekly during the outbreak. FINDINGS The genomic analysis revealed that 10 of 11 non-duplicated E. kobei isolated from neonatal blood cultures between July and September 2016 were clonal, confirming the outbreak. The isolates carried AMR genes including blaAmpC and mcr-10 conferring reduced susceptibility to carbapenem and colistin respectively. The environmental sampling however failed to isolate any Enterobacter spp. Reinforcement of aseptic protocols in invasive procedures, hand hygiene, environmental decontamination, fumigation, and secluded care of culture positive cases successfully terminated the outbreak. CONCLUSION Our study underscored the need to implement stringent infection control measures to prevent infection outbreaks. Further, for the first time, we report the emergence of carbapenem and colistin non-susceptible E. kobei carrying mcr-10 gene as an important cause of nosocomial neonatal sepsis in an NICU.
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Affiliation(s)
- Sulochana Manandhar
- Oxford University Clinical Research Unit, Patan Academy of Health Sciences, Kathmandu, Nepal; Centre for Tropical Medicine and Global Health, Medical sciences division, Nuffield Department of Medicine, University of Oxford, Linacre College, Oxford, UK
| | - Quynh Nguyen
- Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Duy Thanh Pham
- Centre for Tropical Medicine and Global Health, Medical sciences division, Nuffield Department of Medicine, University of Oxford, Linacre College, Oxford, UK; Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Puja Amatya
- Department of Pediatrics, Patan Academy of Health Sciences, Kathmandu, Nepal
| | - Maia Rabaa
- Centre for Tropical Medicine and Global Health, Medical sciences division, Nuffield Department of Medicine, University of Oxford, Linacre College, Oxford, UK; Oxford University Clinical Research Unit, Ho Chi Minh City, Vietnam
| | - Sabina Dongol
- Oxford University Clinical Research Unit, Patan Academy of Health Sciences, Kathmandu, Nepal
| | - Buddha Basnyat
- Oxford University Clinical Research Unit, Patan Academy of Health Sciences, Kathmandu, Nepal; Centre for Tropical Medicine and Global Health, Medical sciences division, Nuffield Department of Medicine, University of Oxford, Linacre College, Oxford, UK
| | | | - Stephen Baker
- Cambridge Institute of Therapeutic Immunology & Infectious Disease (CITIID) Department of Medicine, University of Cambridge, Cambridge, UK
| | - Abhilasha Karkey
- Oxford University Clinical Research Unit, Patan Academy of Health Sciences, Kathmandu, Nepal; Centre for Tropical Medicine and Global Health, Medical sciences division, Nuffield Department of Medicine, University of Oxford, Linacre College, Oxford, UK.
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Shrief R, Hassan RH, Zaki MES, Rizk MA. Molecular Study of Klebsiella Oxytoca Associated with Urinary Tract Infection in Children. Open Microbiol J 2022. [DOI: 10.2174/18742858-v16-e2201070] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022] Open
Abstract
Background:
There are scarce reports about the association of Klebsiella oxytoca (K. oxytoca) with urinary tract infection (UTI) in children. We aimed to evaluate the prevalence of fimA, mrkA, matB and pilQ adhesins genes and extended-spectrum beta-lactamase (ESBL) genes blaCTX-M, blaTEM and blaSHV by polymerase chain reaction (PCR) and to study biofilm formation and antibiotics resistance in K. oxytoca from children with UTI.
Methods:
This study was a retrospective cross-sectional study that included 120 children with UTI due to K. oxytoca. The bacteria were subjected to molecular detection of fimA, mrkA, matB and pilQ adhesins genes and ESBL genes blaCTX-M, blaTEM and blaSHV by PCR. Biofilm capacity was determined by the microtiter plate method.
Results:
The isolated K. oxytoca had positive ESBL activity in 45.8% of isolates. About 40% of isolates were biofilm producers. The frequency of adhesion genes among K. oxytoca was 91.7%, 83.3%, 48.3% and 37.5% for matB, pilQ, fimA and mrkA genes, respectively. For ESBL genes, the frequency was 38.3%, 36.7% and 33.3% for blaCTX-M, blaSHV and blaTEM genes, respectively. The commonest genes among ESBL isolates were blaCTX-M (83.6%), blaSHV (80%) then blaTEM gene (72.7%). A significant association (p=0.048) was detected between ESBL activity and biofilm formation by K. oxytoca.
Conclusion:
Present study highlights the emergence of K. oxytoca as a pathogen associated with UTI in children. There was a high prevalence of adhesin genes and ESBL genes among these isolates. The capacity of K. oxytoca to form biofilm was associated with ESBL production.
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Klebsiella oxytoca Complex: Update on Taxonomy, Antimicrobial Resistance, and Virulence. Clin Microbiol Rev 2021; 35:e0000621. [PMID: 34851134 DOI: 10.1128/cmr.00006-21] [Citation(s) in RCA: 45] [Impact Index Per Article: 15.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/05/2023] Open
Abstract
Klebsiella oxytoca is actually a complex of nine species-Klebsiella grimontii, Klebsiella huaxiensis, Klebsiella michiganensis, K. oxytoca, Klebsiella pasteurii, Klebsiella spallanzanii, and three unnamed novel species. Phenotypic tests can assign isolates to the complex, but precise species identification requires genome-based analysis. The K. oxytoca complex is a human commensal but also an opportunistic pathogen causing various infections, such as antibiotic-associated hemorrhagic colitis (AAHC), urinary tract infection, and bacteremia, and has caused outbreaks. Production of the cytotoxins tilivalline and tilimycin lead to AAHC, while many virulence factors seen in Klebsiella pneumoniae, such as capsular polysaccharides and fimbriae, have been found in the complex; however, their association with pathogenicity remains unclear. Among the 5,724 K. oxytoca clinical isolates in the SENTRY surveillance system, the rates of nonsusceptibility to carbapenems, ceftriaxone, ciprofloxacin, colistin, and tigecycline were 1.8%, 12.5%, 7.1%, 0.8%, and 0.1%, respectively. Resistance to carbapenems is increasing alarmingly. In addition to the intrinsic blaOXY, many genes encoding β-lactamases with varying spectra of hydrolysis, including extended-spectrum β-lactamases, such as a few CTX-M variants and several TEM and SHV variants, have been found. blaKPC-2 is the most common carbapenemase gene found in the complex and is mainly seen on IncN or IncF plasmids. Due to the ability to acquire antimicrobial resistance and the carriage of multiple virulence genes, the K. oxytoca complex has the potential to become a major threat to human health.
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Liu F, Tang C, Wang D, Sun Z, Du L, Wang D. The synergistic effects of phenyllactic acid and slightly acid electrolyzed water to effectively inactivate Klebsiella oxytoca planktonic and biofilm cells. Food Control 2021. [DOI: 10.1016/j.foodcont.2020.107804] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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Antibiofilm and antivirulence potential of silver nanoparticles against multidrug-resistant Acinetobacter baumannii. Sci Rep 2021; 11:10751. [PMID: 34031472 PMCID: PMC8144575 DOI: 10.1038/s41598-021-90208-4] [Citation(s) in RCA: 64] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2020] [Accepted: 04/26/2021] [Indexed: 11/08/2022] Open
Abstract
We aimed to isolate Acinetobacter baumannii (A. baumannii) from wound infections, determine their resistance and virulence profile, and assess the impact of Silver nanoparticles (AgNPs) on the bacterial growth, virulence and biofilm-related gene expression. AgNPs were synthesized and characterized using TEM, XRD and FTIR spectroscopy. A. baumannii (n = 200) were isolated and identified. Resistance pattern was determined and virulence genes (afa/draBC, cnf1, cnf2, csgA, cvaC, fimH, fyuA, ibeA, iutA, kpsMT II, PAI, papC, PapG II, III, sfa/focDE and traT) were screened using PCR. Biofilm formation was evaluated using Microtiter plate method. Then, the antimicrobial activity of AgNPs was evaluated by the well-diffusion method, growth kinetics and MIC determination. Inhibition of biofilm formation and the ability to disperse biofilms in exposure to AgNPs were evaluated. The effect of AgNPs on the expression of virulence and biofilm-related genes (bap, OmpA, abaI, csuA/B, A1S_2091, A1S_1510, A1S_0690, A1S_0114) were estimated using QRT-PCR. In vitro infection model for analyzing the antibacterial activity of AgNPs was done using a co-culture infection model of A. baumannii with human fibroblast skin cell line HFF-1 or Vero cell lines. A. baumannii had high level of resistance to antibiotics. Most of the isolates harbored the fimH, afa/draBC, cnf1, csgA and cnf2, and the majority of A. baumannii produced strong biofilms. AgNPs inhibited the growth of A. baumannii efficiently with MIC ranging from 4 to 25 µg/ml. A. baumannii showed a reduced growth rate in the presence of AgNPs. The inhibitory activity and the anti-biofilm activity of AgNPs were more pronounced against the weak biofilm producers. Moreover, AgNPs decreased the expression of kpsMII , afa/draBC,bap, OmpA, and csuA/B genes. The in vitro infection model revealed a significant antibacterial activity of AgNPs against extracellular and intracellular A. baumannii. AgNPs highly interrupted bacterial multiplication and biofilm formation. AgNPs downregulated the transcription level of important virulence and biofilm-related genes. Our findings provide an additional step towards understanding the mechanisms by which sliver nanoparticles interfere with the microbial spread and persistence.
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Santiago AJ, Donlan RM. Bacteriophage Infections of Biofilms of Health Care-Associated Pathogens: Klebsiella pneumoniae. EcoSal Plus 2020; 9. [PMID: 33118486 DOI: 10.1128/ecosalplus.esp-0029-2019] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/31/2022]
Abstract
Members of the family Enterobacteriaceae, such as Klebsiella pneumoniae, are considered both serious and urgent public health threats. Biofilms formed by these health care-associated pathogens can lead to negative and costly health outcomes. The global spread of antibiotic resistance, coupled with increased tolerance to antimicrobial treatments in biofilm-associated bacteria, highlights the need for novel strategies to overcome treatment hurdles. Bacteriophages (phages), or viruses that infect bacteria, have reemerged as one such potential strategy. Virulent phages are capable of infecting and killing their bacterial hosts, in some cases producing depolymerases that are able to hydrolyze biofilms. Phage therapy does have its limitations, however, including potential narrow host ranges, development of bacterial resistance to infection, and the potential spread of phage-encoded virulence genes. That being said, advances in phage isolation, screening, and genome sequencing tools provide an upside in overcoming some of these limitations and open up the possibilities of using phages as effective biofilm control agents.
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Affiliation(s)
- Ariel J Santiago
- Clinical and Environmental Microbiology Branch, Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA, USA
| | - Rodney M Donlan
- Clinical and Environmental Microbiology Branch, Division of Healthcare Quality Promotion, Centers for Disease Control and Prevention, Atlanta, GA, USA
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