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Microbiology Spectrum Dec 2023Respiratory infections are a leading cause of morbidity and mortality in people with cystic fibrosis (CF). These infections are polymicrobial in nature with overt...
Respiratory infections are a leading cause of morbidity and mortality in people with cystic fibrosis (CF). These infections are polymicrobial in nature with overt pathogens and other colonizing microbes present. Microbiome data have indicated that the presence of oral commensal bacteria in the lungs is correlated with improved outcomes. We hypothesize that one oral commensal, inhibits CF pathogens and modulates the host immune response. One major CF pathogen is , a Gram-negative, opportunistic bacterium with intrinsic drug resistance and an arsenal of virulence factors. We have previously shown that inhibits in a nitrite-dependent manner through the production of reactive nitrogen intermediates. In this study, we demonstrate that while this mechanism is evident in a cell culture model of the CF airway, an alternative mechanism by which may improve outcomes for people with CF is through immunomodulation.
Topics: Humans; Nitrites; Pseudomonas aeruginosa; Biofilms; Pseudomonas Infections; Cystic Fibrosis; Lung; Respiratory Mucosa
PubMed: 37800950
DOI: 10.1128/spectrum.02198-23 -
Brazilian Journal of Microbiology :... Sep 2023Pseudomonas aeruginosa is a common infectious agent associated with respiratory diseases in boas and pythons, however, the histopathology, resistance and virulence are...
Pseudomonas aeruginosa is a common infectious agent associated with respiratory diseases in boas and pythons, however, the histopathology, resistance and virulence are yet described for this species. In this study, we investigated a dying Burmese python rescued from tropical rainforest in Hainan. Clinical signs were open-mouthed breathing, abnormal shedding and anorexia. Abundant yellow mucopurulent secretions were observed in highly ectatic segmental bronchi by postmortem. Histopathological lesions included systemic pneumonia, enteritis, nephritis and carditis. P. aeruginosa was the only species isolated from heart blood, kidney, trachea and lung. The phenotype analysis demonstrated that the isolates had strong biofilm, and were sensitive to amikacin, spectinomycin, ciprofloxacin, norfloxacin and polymyxin B, moreover, the LD of the most virulent isolate was 2.22×10 cfu/mL in a zebrafish model. Molecular epidemiological analysis revealed that the isolates belonged to sequence type 3495, the common gene patterns were toxA + exoSYT + phzIM + plcHN in virulence and catB + bla + ant (3'')-I+ tetA in resistance. This study highlights that P. aeruginosa should be worth more attention in wildlife conservation and raise the public awareness for the cross infection and cross spread between animals and human.
Topics: Animals; Anti-Bacterial Agents; Bacteremia; Boidae; Cross Infection; Pneumonia; Pseudomonas aeruginosa; Pseudomonas Infections; Zebrafish
PubMed: 37344655
DOI: 10.1007/s42770-023-01038-7 -
Journal of Innate Immunity 2024Upon infection, mucosal tissues activate a brisk inflammatory response to clear the pathogen, i.e., resistance to disease. Resistance to disease is orchestrated by... (Review)
Review
BACKGROUND
Upon infection, mucosal tissues activate a brisk inflammatory response to clear the pathogen, i.e., resistance to disease. Resistance to disease is orchestrated by tissue-resident macrophages, which undergo profound metabolic reprogramming after sensing the pathogen. These metabolically activated macrophages release many inflammatory factors, which promote their bactericidal function. However, in immunocompetent individuals, pathogens like Pseudomonas aeruginosa, Staphylococcus aureus, and Salmonella evade this type of immunity, generating communities that thrive for the long term.
SUMMARY
These organisms develop features that render them less susceptible to eradication, such as biofilms and increased tolerance to antibiotics. Furthermore, after antibiotic therapy withdrawal, "persister" cells rapidly upsurge, triggering inflammatory relapses that worsen host health. How these pathogens persisted in inflamed tissues replete with activated macrophages remains poorly understood.
KEY MESSAGES
In this review, we discuss recent findings indicating that the ability of P. aeruginosa, S. aureus, and Salmonella to evolve biofilms and antibiotic tolerance is promoted by the similar metabolic routes that regulate macrophage metabolic reprogramming.
Topics: Biofilms; Humans; Animals; Macrophages; Anti-Bacterial Agents; Bacterial Infections; Pseudomonas aeruginosa; Staphylococcus aureus; Drug Resistance, Bacterial; Immune Evasion
PubMed: 38310854
DOI: 10.1159/000536649 -
Nucleosides, Nucleotides & Nucleic Acids 2024possesses a variety of virulence factors that may contribute to its pathogenicity, and relationship has been determined between antibiotic resistance and biofilm. The...
INTRODUCTION
possesses a variety of virulence factors that may contribute to its pathogenicity, and relationship has been determined between antibiotic resistance and biofilm. The aim of this study was to investigate the virulence factors of isolates by genotypic and phenotypic methods, as well as whether there is a relationship between other virulence factors and antibiotic resistance.
METHODS
A total of 80 strains were sent from various clinics included in the study. Identification and antibiotic resistance profile of isolates were determined by Vitek 2 (Biomerioux, France) automated system. P agar, F agar, and motility test medium were used for phenotyping tests. , , , and were evaluated with Real-time PCR (Anatolia, Geneworks, Turkey).
RESULTS
The highest rates of antibiotic resistance were observed against imipenem (42.5%) and meropenem (40%). Among the isolates, 81.3% tested positive for , 30% for , 32.5% for , and 42.5% for . Additionally, 70.4% of the isolates tested positive for pyocyanin, 41.3% for pyoverdine, 1.8% for pyorubin, and 8.9% tested negative for pyorubin. No statistically significant difference was found between antibiotic resistance and the presence of virulence factors ( > 0.005).
CONCLUSIONS
The relationship between antibiotic resistance and virulence factors is controversial. There are studies demonstrating the relationship between virulence factors and antibiotic resistance, as well as studies that indicate the absence of such a relationship. Investigating virulence and antibiotic resistance rates may be important for identifying potential drug targets for subsequent research.
Topics: Humans; Virulence Factors; Pseudomonas aeruginosa; Agar; Virulence; Pseudomonas Infections; Anti-Bacterial Agents; Microbial Sensitivity Tests; Organic Chemicals
PubMed: 37665184
DOI: 10.1080/15257770.2023.2254346 -
Microbes and Infection 2024Chronic lung infections caused by Pseudomonas aeruginosa play a significant role in the mortality and morbidity of cystic fibrosis (CF) patients. The widespread...
Cell-free supernatants from Lactobacillus strains exert antibacterial, antibiofilm, and antivirulence activity against Pseudomonas aeruginosa from cystic fibrosis patients.
Chronic lung infections caused by Pseudomonas aeruginosa play a significant role in the mortality and morbidity of cystic fibrosis (CF) patients. The widespread bacterial resistance to conventional antimicrobials demands identifying new strategies to complement or replace current antibiotic therapies. In this study, we evaluated the antibacterial, antibiofilm, and antivirulence properties of cell-free supernatants (CFS) from several Lactobacillus probiotic strains against P. aeruginosa isolated from the sputum of CF patients. A strong and fast antibacterial activity of CFS from different strains of lactobacilli was observed at acidic pH towards P. aeruginosa, both in planktonic and biofilm mode of growth, in conditions mimicking CF lung. Interestingly, although when adjusted at pH 6.0, CFS lost most of their antibacterial potential, they retained some antivirulence activity towards P. aeruginosa, largely dependent on the dose, exposure time, and the Lactobacillus-P. aeruginosa strain combination. In vivo testing in the invertebrate Galleria mellonella model disclosed the lack of toxicity of acidic CFS and their ability to prevent P. aeruginosa infection. For the first time, the results revealed lactobacilli postbiotic activities in the context of the pulmonary environment, pointing to innovative postbiotics' uses in anti-infective therapy.
Topics: Cystic Fibrosis; Pseudomonas aeruginosa; Biofilms; Humans; Pseudomonas Infections; Animals; Lactobacillus; Anti-Bacterial Agents; Sputum; Hydrogen-Ion Concentration; Probiotics; Moths; Antibiosis
PubMed: 38237656
DOI: 10.1016/j.micinf.2024.105301 -
Parasitology Aug 2023For infections to be maintained in a population, pathogens must compete to colonize hosts and transmit between them. We use an experimental approach to investigate...
For infections to be maintained in a population, pathogens must compete to colonize hosts and transmit between them. We use an experimental approach to investigate within-and-between host dynamics using the pathogen and the animal host Within-host interactions can involve the production of goods that are beneficial to all pathogens in the local environment but susceptible to exploitation by non-producers. We exposed the nematode host to ‘producer’ and two ‘non-producer’ bacterial strains (specifically for siderophore production and quorum sensing), in single infections and coinfections, to investigate within-host colonization. Subsequently, we introduced infected nematodes to pathogen-naive populations to allow natural transmission between hosts. We find that producer pathogens are consistently better at colonizing hosts and transmitting between them than non-producers during coinfection and single infection. Non-producers were poor at colonizing hosts and between-host transmission, even when coinfecting with producers. Understanding pathogen dynamics across these multiple levels will ultimately help us predict and control the spread of infections, as well as contribute to explanations for the persistence of cooperative genotypes in natural populations.
Topics: Animals; Bacteria; Quorum Sensing; Caenorhabditis elegans; Pseudomonas aeruginosa; Coinfection
PubMed: 37394480
DOI: 10.1017/S0031182023000586 -
Archives of Microbiology Jun 2024Among the ESKAPE pathogens, Pseudomonas aeruginosa is an extensively notorious superbug that causes difficult-to-treat infections. Since quorum sensing (QS) directly...
Among the ESKAPE pathogens, Pseudomonas aeruginosa is an extensively notorious superbug that causes difficult-to-treat infections. Since quorum sensing (QS) directly promotes pseudomonal virulence, targeting QS circuits is a promising approach for disarming phenotypic virulence. Hence, this study scrutinizes the anti-QS, antivirulence, and anti-biofilm potential of citral (CiT; phytochemical) and triclosan (TcN; disinfectant), alone and in combination, against P. aeruginosa PAO1/PA14. The findings confirmed synergism between CiT and TcN and revealed their quorum quenching (QQ) potential. At sub-inhibitory levels, CiT-TcN combination significantly impeded pyocyanin, total bacterial protease, hemolysin, and pyochelin production alongside inhibiting biofilm formation in P. aeruginosa. Moreover, the QQ and antivirulence potential of CiT and TcN was positively correlated by molecular docking studies that predicted strong associations of the drugs with QS receptors of P. aeruginosa. Collectively, the study identifies CiT-TcN as an effective drug combination that harbors QQ, antivirulence, and anti-biofilm prospects against P. aeruginosa.
Topics: Pseudomonas aeruginosa; Quorum Sensing; Triclosan; Biofilms; Acyclic Monoterpenes; Drug Synergism; Molecular Docking Simulation; Anti-Bacterial Agents; Virulence; Bacterial Proteins; Pyocyanine
PubMed: 38913239
DOI: 10.1007/s00203-024-04059-4 -
Molecular Biology Reports Feb 2024Recently, lipase processing for biodiesel production has shown a global increase as it is considered a potential alternative clean-fuel source. The current study's...
BACKGROUND
Recently, lipase processing for biodiesel production has shown a global increase as it is considered a potential alternative clean-fuel source. The current study's objective is to investigate of lipolytic activity of lipase produced from different strains of Pseudomonas aeruginosa (P. aeruginosa) in biodiesel production using edible plant oils. The goal is to develop an efficient and cost-effective method for producing inexpensive and environmentally friendly biodiesel.
METHODS AND RESULTS
Four P. aeruginosa isolates were obtained from different environmental sources (soil), phenotypically identified, and it was confirmed by the PCR detection of the 16SrRNA gene. The isolated P. aeruginosa strains were screened for lipase production, and the recovered lipase was purified. Besides, the lipase (lip) gene was detected by PCR, and the purified PCR products were sequenced and analyzed. The production of biofuel was conducted using gas chromatography among tested oils. It was found that castor oil was the best one that enhances lipase production in-vitro.
Topics: Humans; Biofuels; Pseudomonas aeruginosa; Lipase; Oils; Base Sequence; Pseudomonas Infections; Plant Oils
PubMed: 38393680
DOI: 10.1007/s11033-023-09156-z -
Scientific Reports Oct 2023Pseudomonas aeruginosa is resistant to a wide range of extended spectrum-lactamases (ESBLs) antibiotics because it produces several kinds of ESBLs. The goal of the...
Pseudomonas aeruginosa is resistant to a wide range of extended spectrum-lactamases (ESBLs) antibiotics because it produces several kinds of ESBLs. The goal of the current investigation was to identify the bacteria that produce extended spectrum -lactamases and the genes that encode three different ESBLs, such as bla, bla and bla genes in Pseudomonas aeruginosa isolated from burn patients. In this investigation, 71 Pseudomonas aeruginosa isolates were isolated from burn wounds in Burn and Plastic Surgery Hospital, Duhok City between July 2021 to June 2022. For the purpose of finding the bla, bla, and bla ESBL expressing genes, Polymerase Chain Reaction (PCR) was used. Among 71 Pseudomonas aeruginosa isolates, 26.36% (29/71) were isolated from males and 38.18% (42/71) from females, and 76.06% (54/71) of the isolates were multidrug resistant. They exhibited higher resistance against Piperacillin with resistance rates of 98.59%. Among the ESBL-producing isolates tested, bla was found in 59.26% (32), bla was found in 44.44% (24), and bla was found in 11.11% (6). All isolates must undergo antimicrobial susceptibility testing because only a few numbers of the available antibiotics are effective for the treatment of this bacterium. This will prevent the development of resistance in burn units and aids in the management of the treatment plan.
Topics: Female; Humans; Male; Anti-Bacterial Agents; beta-Lactamases; Microbial Sensitivity Tests; Pseudomonas aeruginosa; Transcription Factors; Burns
PubMed: 37884651
DOI: 10.1038/s41598-023-45417-4 -
Experimental and Clinical... Apr 2024In this study, we analyzed the effects of carbapenem-resistant Pseudomonas aeruginosa infection and mixed infection on the perioperative prognosis of lung transplant...
OBJECTIVES
In this study, we analyzed the effects of carbapenem-resistant Pseudomonas aeruginosa infection and mixed infection on the perioperative prognosis of lung transplant recipients and studied statistics on antibiotic resistance in P aeruginosa.
MATERIALS AND METHODS
This was a retrospective casecontrol study. We collected data on lung transplant recipients with combined lower respiratory tract P aeruginosa infection within 48 hours after lung transplant at the China-Japan Friendship Hospital from August 2018 to April 2022. We grouped recipients according to P aeruginosa resistance to carbapenem antibiotics and summarized the clinical characteristics of carbapenem-resistant P aeruginosa infection. We analyzed the effects of carbapenemresistant P aeruginosa infection and mixed infections on all-cause mortality 30 days after lung transplant by Cox regression. We used the Kaplan-Meier method to plot survival curves.
RESULTS
Patients in the carbapenem-resistant P aeruginosa group had a higher all-cause mortality rate than those in the carbapenem-sensitive P aeruginosa group at both 7 days (6 patients [22.3%] vs 2 patients [4.5%]; P = .022) and 30 days (12 patients [44.4%] vs 7 patients [15.9%]; P = .003) after lung transplant. In multivariate analysis, both carbapenemresistant P aeruginosa infection and P aeruginosa combined with bacterial infection were independent risk factors for death 30 days after transplant in lung transplant recipients (P < .05). In subgroup analysis, carbapenem-resistant P aeruginosa combined with bacterial infection increased the risk of death 30 days after transplant in lung transplant recipients compared with carbapenem-sensitive P aeruginosa combined with bacterial infection (12 patients [60%] vs 6 patients [19.4%]; P < .001).
CONCLUSIONS
Combined lower respiratory tract carbapenem-resistant P aeruginosa infection and P aeruginosa combined with bacterial infection early after lung transplant increased the risk of 30-day mortality after lung transplant.
Topics: Humans; Pseudomonas aeruginosa; Retrospective Studies; Pseudomonas Infections; Risk Factors; Lung Transplantation; Carbapenems; Female; Male; Middle Aged; Time Factors; Anti-Bacterial Agents; Adult; Treatment Outcome; Coinfection; Risk Assessment; beta-Lactam Resistance
PubMed: 38742321
DOI: 10.6002/ect.2023.0268