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Scientific Reports Apr 2022Biofilm-associated infections are of great concern because they are associated with antibiotic resistance and immune evasion. Co-colonization by Staphylococcus aureus...
Biofilm-associated infections are of great concern because they are associated with antibiotic resistance and immune evasion. Co-colonization by Staphylococcus aureus and Streptococcus pneumoniae is possible and a threat in clinical practice. We investigated the interaction between S. aureus and S. pneumoniae in mixed biofilms and tested new antibiofilm therapies with antioxidants N-acetyl-L-cysteine (NAC) and cysteamine (Cys). We developed two in vitro S. aureus-S. pneumoniae mixed biofilms in 96-well polystyrene microtiter plates and we treated in vitro biofilms with Cys and NAC analyzing their effect by CV staining and viable plate counting. S. pneumoniae needed a higher proportion of cells in the inoculum and planktonic culture to reach a similar population rate in the mixed biofilm. We demonstrated the effect of Cys in preventing S. aureus biofilms and S. aureus-S. pneumoniae mixed biofilms. Moreover, administration of 5 mg/ml of NAC nearly eradicated the S. pneumoniae population and killed nearly 94% of MSSA cells and 99% of MRSA cells in the mixed biofilms. The methicillin resistance background did not change the antioxidants effect in S. aureus. These results identify NAC and Cys as promising repurposed drug candidates for the prevention and treatment of mixed biofilms by S. pneumoniae and S. aureus.
Topics: Acetylcysteine; Anti-Bacterial Agents; Antioxidants; Biofilms; Cysteamine; Methicillin; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Staphylococcus aureus; Streptococcus pneumoniae
PubMed: 35461321
DOI: 10.1038/s41598-022-10609-x -
FEMS Immunology and Medical Microbiology Feb 2006Staphylococcal cassette chromosome (SCC) elements are, so far, the only vectors described for the mecA gene encoding methicillin resistance in staphylococci. SCCmec... (Review)
Review
Staphylococcal cassette chromosome (SCC) elements are, so far, the only vectors described for the mecA gene encoding methicillin resistance in staphylococci. SCCmec elements are classified according to the type of recombinase they carry and their general genetic composition. SCCmec types I-V have been described, and SCC elements lacking mecA have also been reported. In this review, we summarize the current knowledge about SCC structure and distribution, including genetic variants and rudiments of the elements. Its origin is still unknown, but one assumes that staphylococcal cassette chromosome is transferred between staphylococci, and mecA-positive coagulase-negative staphylococci may be a potential reservoir for these elements. Staphylococcal genomes seem to change continuously as genetic elements move in and out, but no mechanism of transfer has been found responsible for moving SCC elements between different staphylococcal species. Observations suggesting de novo production of methicillin-resistant staphylococci and horizontal gene transfer of SCCmec will be discussed.
Topics: Chromosomes, Bacterial; Gene Transfer, Horizontal; Genes, Bacterial; Genome, Bacterial; Interspersed Repetitive Sequences; Methicillin; Methicillin Resistance; Staphylococcus aureus
PubMed: 16420592
DOI: 10.1111/j.1574-695X.2005.00009.x -
Microbiology Spectrum Sep 2021Antibiotic resistance is one of the largest threats facing global health. Wastewater treatment plants are well-known hot spots for interaction between diverse bacteria,...
Antibiotic resistance is one of the largest threats facing global health. Wastewater treatment plants are well-known hot spots for interaction between diverse bacteria, genetic exchange, and antibiotic resistance. Nonpathogenic bacteria theoretically act as reservoirs of antibiotic resistance subsequently transferring antibiotic resistance genes to pathogens, indicating that evolutionary processes occur outside clinical settings and may drive patterns of drug-resistant infections. We isolated and sequenced 100 bacterial strains from five wastewater treatment plants to analyze regional dynamics of antibiotic resistance in the California Central Valley. The results demonstrate the presence of a wide diversity of pathogenic and nonpathogenic bacteria, with an arithmetic mean of 5.1 resistance genes per isolate. Forty-three percent of resistance genes were located on plasmids, suggesting that large levels of gene transfer between bacteria that otherwise may not co-occur are facilitated by wastewater treatment. One of the strains detected was a carrying pX01 and pX02 anthrax-like plasmids and multiple drug resistance genes. A correlation between resistance genes and taxonomy indicates that taxon-specific evolutionary studies may be useful in determining and predicting patterns of antibiotic resistance. Conversely, a lack of geographic correlation may indicate that landscape genetic studies to understand the spread of antibiotic resistance genes should be carried out at broader scales. This large data set provides insights into how pathogenic and nonpathogenic bacteria interact in wastewater environments and the resistance genes which may be horizontally transferred between them. This can help in determining the mechanisms leading to the increasing prevalence of drug-resistant infections observed in clinical settings. The reasons for the increasing prevalence of antibiotic-resistant infections are complex and associated with myriad clinical and environmental processes. Wastewater treatment plants operate as nexuses of bacterial interaction and are known hot spots for genetic exchange between bacteria, including antibiotic resistance genes. We isolated and sequenced 100 drug-resistant bacteria from five wastewater treatment plants in California's Central Valley, characterizing widespread gene sharing between pathogens and nonpathogens. We identified a novel, multiresistant carrying anthrax-like plasmids. This empirical study supports the likelihood of evolutionary and population processes in the broader environment affecting the prevalence of clinical drug-resistant infections and identifies several taxa that may operate as reservoirs and vectors of antibiotic resistance genes.
Topics: Anti-Bacterial Agents; Bacteria; Bacterial Proteins; Carbapenems; Drug Resistance, Multiple, Bacterial; Genome, Bacterial; Genomics; Methicillin; Plasmids; Sewage; Water Purification
PubMed: 34132566
DOI: 10.1128/Spectrum.00128-21 -
The Journal of Bone and Joint Surgery.... Nov 2008Methicillin-resistant Staphylococcus aureus (MRSA) has become a ubiquitous bacterium in both the hospital and community setting. There are two major subclassifications... (Review)
Review
Methicillin-resistant Staphylococcus aureus (MRSA) has become a ubiquitous bacterium in both the hospital and community setting. There are two major subclassifications of MRSA, community-acquired and healthcare-acquired, each with differing pathogenicity and management. MRSA is increasingly responsible for infections in otherwise healthy, active adults. Local outbreaks affect both professional and amateur athletes and there is increasing public awareness of the issue. Health-acquired MRSA has major cost and outcome implications for patients and hospitals. The increasing prevalence and severity of MRSA means that the orthopaedic community should have a basic knowledge of the bacterium, its presentation and options for treatment. This paper examines the evolution of MRSA, analyses the spectrum of diseases produced by this bacterium and presents current prevention and treatment strategies for orthopaedic infections from MRSA.
Topics: Anti-Bacterial Agents; Community-Acquired Infections; Cross Infection; Drug Resistance, Multiple, Bacterial; Humans; Methicillin; Methicillin-Resistant Staphylococcus aureus; Orthopedics; Staphylococcal Infections
PubMed: 18978255
DOI: 10.1302/0301-620X.90B11.20771 -
JPMA. the Journal of the Pakistan... Apr 2023To characterise the biofilm matrix composition of a newly described Staphylococcus aureus biofilm phenotype.
OBJECTIVES
To characterise the biofilm matrix composition of a newly described Staphylococcus aureus biofilm phenotype.
METHOD
This experimental study was conducted at the Faculty of Pharmacy, Helwan University, Cairo, Egypt, from January 2021 to March 2022, and comprised methicillin-resistant Staphylococcus aureus and methicillin-susceptible Staphylococcus aureus biofilm-forming clinical isolates which were allowed to construct biofilms under two distinct culture conditions; one a commonly used condition, and the other one a novel, more biologically-relevant condition. The formed biofilms were analysed for matrix composition through treatment with proteinase,sodium meta-periodate, and streptokinase. The efficacy of Cis-2-Decenoic acid and hamamelitannin on the biologically-relevant biofilms was evaluated using biofilm viability assay based on a colorimetric assay for measuring cell metabolic activity and scanning electron microscope imaging. Data was analysed using GraphPad Prism 5.01.
RESULTS
Of the 58 isolates, 45(77.6%) were methicillin-resistant Staphylococcus aureus and 13(22.4%) were methicillin susceptible Staphylococcus aureus. There was significant difference in responses to streptokinase, proteinase and sodium meta-periodate (p<0.05) among the differentially-developed biofilms in methicillin-resistant Staphylococcus aureus isolates. Regarding the methicillin-susceptible Staphylococcus aureus isolates, the differentially-developed biofilms showed significantly different liabilities to streptokinase only (p<0.05). Mean biofilm inhibition for Cis-2- Decenoic acid was 54.27±27.93% and mean biofilm dispersion was 71.92±11.59% while the corresponding valuesfor hamamelitannin were 83.03±13.95% and 70.48±7.116% against the newly described methicillin-resistant Staphylococcus aureus biofilm phenotype.
CONCLUSIONS
Applying biologically-relevant culture conditions on staphylococci biofilms and antibiofilm drugs is recommended.
Topics: Humans; Staphylococcus aureus; Methicillin-Resistant Staphylococcus aureus; Methicillin; Anti-Bacterial Agents; Staphylococcal Infections; Biofilms; Peptide Hydrolases; Phenotype; Streptokinase; Sodium; Microbial Sensitivity Tests
PubMed: 37482852
DOI: 10.47391/JPMA.EGY-S4-34 -
The Cochrane Database of Systematic... Jul 2018Cystic fibrosis is an inherited life-threatening multisystem disorder with lung disease characterized by abnormally thick airway secretions and persistent bacterial... (Review)
Review
BACKGROUND
Cystic fibrosis is an inherited life-threatening multisystem disorder with lung disease characterized by abnormally thick airway secretions and persistent bacterial infection. Chronic, progressive lung disease is the most important cause of morbidity and mortality in the condition and is therefore the main focus of clinical care and research. Staphylococcus aureus is a major cause of chest infection in people with cystic fibrosis. Early onset, as well as chronic, lung infection with this organism in young children and adults results in worsening lung function, poorer nutrition and increases the airway inflammatory response, thus leading to a poor overall clinical outcome. There are currently no evidence-based guidelines for chronic suppressive therapy for Staphylococcus aureus infection in cystic fibrosis such as those used for Pseudomonas aeruginosa infection. This is an update of a previously published review.
OBJECTIVES
To assess the evidence regarding the effectiveness of long-term antibiotic treatment regimens for chronic infection with methicillin-sensitive Staphylococcus aureus (MSSA) infection in people with cystic fibrosis and to determine whether this leads to improved clinical and microbiological outcomes.
SEARCH METHODS
Trials were identified by searching the Cochrane Cystic Fibrosis and Genetic Disorders Group's Cystic Fibrosis Trials Register, MEDLINE, Embase, handsearching article reference lists and through contact with local and international experts in the field. Date of the last search of the Group's Cystic Fibrosis Trials Register: 09 February 2018.We also searched ongoing trials databases. Date of latest search: 20 May 2018.
SELECTION CRITERIA
Randomised or quasi-randomised controlled trials comparing any combinations of topical, inhaled, oral or intravenous antimicrobials used as suppressive therapy for chronic infection with methicillin-sensitive Staphylococcus aureus compared with placebo or no treatment.
DATA COLLECTION AND ANALYSIS
The authors independently assessed all search results for eligibility. No eligible trials were identified.
MAIN RESULTS
The searches identified 58 trials, but none were eligible for inclusion in the current version of this review.
AUTHORS' CONCLUSIONS
No randomised controlled trials were identified which met the inclusion criteria for this review. Although methicillin-sensitive Staphylococcus aureus is an important and common cause of lung infection in people with cystic fibrosis, there is no agreement on how best to treat long-term infection. The review highlights the need to organise well-designed trials that can provide evidence to support the best management strategy for chronic methicillin-sensitive Staphylococcus aureus infection in people with cystic fibrosis.
Topics: Anti-Bacterial Agents; Cystic Fibrosis; Humans; Methicillin; Respiratory Tract Infections; Staphylococcal Infections; Staphylococcus aureus
PubMed: 30052271
DOI: 10.1002/14651858.CD011581.pub3 -
BMC Complementary and Alternative... Mar 2015To determine the effect of flavonoids in conjunction with antibiotics in methicillin resistant Staphylococcus aureus (MRSA) a study was designed. The flavonoids included...
BACKGROUND
To determine the effect of flavonoids in conjunction with antibiotics in methicillin resistant Staphylococcus aureus (MRSA) a study was designed. The flavonoids included Rutin, Morin, Qurecetin while antibiotics included ampicillin, amoxicillin, cefixime, ceftriaxone, vancomycin, methicillin, cephradine, erythromycin, imipenem, sulphamethoxazole/trimethoprim, ciprofloxacin and levolfloxacin. Test antibiotics were mostly found resistant with only Imipenem and Erythromycin found to be sensitive against 100 MRSA clinical isolates and S. aureus (ATCC 43300). The flavonoids were tested alone and also in different combinations with selected antibiotics.
METHODS
Antibiotics and flavonoids sensitivity assays were carried using disk diffusion method. The combinations found to be effective were sifted through MIC assays by broth macro dilution method. Exact MICs were determined using an incremental increase approach. Fractional inhibitory concentration indices (FICI) were determined to evaluate relationship between antibiotics and flavonoids is synergistic or additive. Potassium release was measured to determine the effect of antibiotic-flavonoids combinations on the cytoplasmic membrane of test bacteria.
RESULTS
Antibiotic and flavonoids screening assays indicated activity of flavanoids against test bacteria. The inhibitory zones increased when test flavonoids were combined with antibiotics facing resistance. MICs of test antibiotics and flavonoids reduced when they were combined. Quercetin was the most effective flavonoid (MIC 260 μg/ml) while morin + rutin + quercetin combination proved most efficient with MIC of 280 + 280 + 140 μg/ml. Quercetin + morin + rutin with amoxicillin, ampicillin, cephradine, ceftriaxone, imipenem, and methicillin showed synergism, while additive relationship was indicated between morin + rutin and amoxicillin, cephradine, ceftriaxone, imipenem, and methicillin. Quercetin alone had an additive effect with ampicillin, cephradine, ceftriaxone, imipenem, and methicillin. Potassium leakage was highest for morin + rutin + quercetin that improved further in combination with imipenem. Morin and rutin alone had no activity but in combination showed activity against test bacteria.
CONCLUSIONS
The flavonoids when used in combination with antibiotics were found to increase each other activity against test bacteria. The relationship between the flavonoids and antibiotics in most of the cases was additive. However in a few cases synergism was also observed. Flavonoids alone or in combinations also damaged bacterial cell membrane.
Topics: Anti-Bacterial Agents; Drug Resistance; Drug Synergism; Flavonoids; Humans; Methicillin; Methicillin-Resistant Staphylococcus aureus; Microbial Sensitivity Tests; Quercetin; Rutin
PubMed: 25879586
DOI: 10.1186/s12906-015-0580-0 -
The Lancet. Infectious Diseases Oct 2005
Review
Topics: Europe; Humans; Incidence; Japan; Methicillin; Methicillin Resistance; Staphylococcal Infections; Staphylococcus aureus; United States
PubMed: 16183520
DOI: 10.1016/S1473-3099(05)70243-7 -
Biocontrol Science 2017Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major pathogens responsible for nosocomial infections. The presence of MRSA in a hospital is...
Methicillin-resistant Staphylococcus aureus (MRSA) is one of the major pathogens responsible for nosocomial infections. The presence of MRSA in a hospital is detrimental to patients and to hospital management. Thus, rapid identification of MRSA is needed. Here, we report on a prospective method to rapidly discriminate of MSSA from MRSA using matrix-assisted laser desorption ionization-time of flight mass spectrometry (MALDI-TOF MS) and support vector machine (SVM) analysis in 160 clinical isolates of S. aureus. The predictive model was tested using 100 S. aureus isolates (50 MSSA and 50 MRSA). The identification rates were 90.0% for MSSA and 87.5% for MRSA in a 10-fold cross-validation SVM. In blind test sets, 60 S. aureus isolates (30 MSSA and 30 MRSA) were correctly classified, with identification rates of 93.3% for MSSA and 86.7% for MRSA. The method proposed in this study using the predictive model enables detection of one colony in 5 minutes, and thus is useful at clinical sites at which rapid discrimination of MRSA from MSSA is required.
Topics: Anti-Bacterial Agents; Humans; Methicillin; Methicillin-Resistant Staphylococcus aureus; Prospective Studies; Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization; Staphylococcal Infections; Staphylococcus aureus
PubMed: 28954959
DOI: 10.4265/bio.22.163 -
International Journal of Molecular... Nov 2023Methicillin-sensitive () (MSSA) bacteremia remains a global challenge, despite the availability of antibiotics. Primary treatments include β-lactam agents such as...
Methicillin-sensitive () (MSSA) bacteremia remains a global challenge, despite the availability of antibiotics. Primary treatments include β-lactam agents such as cefazolin and flucloxacillin. Ongoing discussions have focused on the potential synergistic effects of combining these agents with rifampicin or fosfomycin to combat infections associated with biofilm formation. Managing staphylococcal infections is challenging due to antibacterial resistance, biofilms, and 's ability to invade and replicate within host cells. Intracellular invasion shields the bacteria from antibacterial agents and the immune system, often leading to incomplete bacterial clearance and chronic infections. Additionally, can assume a dormant phenotype, known as the small colony variant (SCV), further complicating eradication and promoting persistence. This study investigated the impact of antibiotic combinations on the persistence of 6850 and its stable small colony variant (SCV strain JB1) focusing on intracellular survival and biofilm formation. The results from the wild-type strain 6850 demonstrate that β-lactams combined with RIF effectively eliminated biofilms and intracellular bacteria but tend to select for SCVs in planktonic culture and host cells. Higher antibiotic concentrations were associated with an increase in the zeta potential of , suggesting reduced membrane permeability to antimicrobials. When using the stable SCV mutant strain JB1, antibiotic combinations with rifampicin successfully cleared planktonic bacteria and biofilms but failed to eradicate intracellular bacteria. Given these findings, it is reasonable to report that β-lactams combined with rifampicin represent the optimal treatment for MSSA bacteremia. However, caution is warranted when employing this treatment over an extended period, as it may elevate the risk of selecting for small colony variants (SCVs) and, consequently, promoting bacterial persistence.
Topics: Humans; Anti-Bacterial Agents; Staphylococcus aureus; Methicillin; Methicillin-Resistant Staphylococcus aureus; Rifampin; Staphylococcal Infections; Biofilms; beta-Lactams; Bacteremia; Microbial Sensitivity Tests
PubMed: 38003500
DOI: 10.3390/ijms242216308