Effect of clpP and clpC deletion on persister cell number in Staphylococcus aureus.

This study was conducted to determine the effect of clpP and clpC deletion on S. aureus persister cell numbers following antibiotic treatment. Deletion of clpP resulted in a significant decrease in persister cells following treatment with oxacillin and erythromycin but not with levofloxacin and daptomycin. Deletion of clpC resulted in a decrease in persister cells following treatment with oxacillin. These differences were dependent on the antibiotic class and the CFU/ml in which the cells were treated. Persister revival assays for all the bacterial strains in these studies demonstrated a significant delay in resumption of growth characteristic of persister cells indicating that the surviving organisms in this study were not likely due to spontaneous antibiotic resistance. Based on our results, ClpP and possibly ClpC plays a role in persister cell formation or maintenance and this effect is dependent on antibiotic class and the CFU/ml or the growth phase of the cells. PMID: 27375177 [PubMed - as supplied by publisher]
Source: Journal of Medical Microbiology - Category: Microbiology Authors: Tags: J Med Microbiol Source Type: research

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CONCLUSION: These results show that levonadifloxacin has an improved bactericidal effect on biofilm-embedded quinolone-resistant S. aureus and meticillin-resistant S. aureus, and that it can be a promising treatment option for such infections. PMID: 31241446 [PubMed - as supplied by publisher]
Source: Journal of Medical Microbiology - Category: Microbiology Authors: Tags: J Med Microbiol Source Type: research
Abstract To date, there has been little experience in using fosfomycin in children. However, its broad spectrum of action and excellent safety profile have renewed interest in this antibiotic, especially for treating infections by multidrug-resistant bacteria. The main indication for fosfomycin in pediatrics is currently community-acquired lower urinary tract infection. Given its good activity against bacteria, fosfomycin can also be useful in urinary infections caused by extended-spectrum beta-lactamase-producing enterobacteria. Fosfomycin presents very good dissemination to tissues including bone and is therefor...
Source: Revista Espanola de Quimioterapia - Category: Drugs & Pharmacology Authors: Tags: Rev Esp Quimioter Source Type: research
Conclusions: We present the most detailed genomic analysis of MRSA isolated in Sri Lanka to date. The analysis identified a PVL-positive ST5-MRSA-IVc that is prevalent among MRSA causing clinical infections in Sri Lanka. Furthermore, this clone was also found among isolates from the United Kingdom and Australia. Introduction Worldwide, Staphylococcus aureus is the primary causative agent of community-acquired skin and soft tissue infections (SSTI) and is an important cause of hospital-associated invasive infections including bacteremia, pneumonia and endocarditis (Bell et al., 2002; David and Daum, 2010). Panton-Va...
Source: Frontiers in cellular and infection microbiology - Category: Microbiology Source Type: research
This study identified prophages as mediators of bacterial virulence in a model of infectious endocarditis, probably through promotion of interaction with extracellular matrix components. Further studies are needed to identify mechanisms leading to promotion of intrinsic virulence. Introduction Challenges related to Staphylococcus aureus infections in the human and veterinary clinics mobilized important human and technical resources. S. aureus can colonize 20–30% of the general population asymptomatically but is also capable of causing a wide spectrum of diseases ranging from benign infections, to particularly...
Source: Frontiers in Microbiology - Category: Microbiology Source Type: research
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Source: Biomed Res - Category: Research Authors: Tags: Biomed Res Int Source Type: research
ueiredo AM Abstract Staphylococcus aureus subsp. aureus, commonly referred as S. aureus, is an important bacterial pathogen frequently involved in hospital- and community-acquired infections in humans, ranging from skin infections to more severe diseases such as pneumonia, bacteraemia, endocarditis, osteomyelitis, and disseminated infections. Here, we report the complete closed genome sequence of a community-acquired methicillin-resistant S. aureus strain, USA400-0051, which is a prototype of the USA400 clone. PMID: 29091141 [PubMed - in process]
Source: Memorias do Instituto Oswaldo Cruz - Category: Infectious Diseases Authors: Tags: Mem Inst Oswaldo Cruz Source Type: research
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Source: Cellular Physiology and Biochemistry - Category: Cytology Source Type: research
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Source: The Annals of Pharmacotherapy - Category: Drugs & Pharmacology Authors: Tags: Ann Pharmacother Source Type: research
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Source: Current Topics in Microbiology and Immunology - Category: Microbiology Tags: Curr Top Microbiol Immunol Source Type: research
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Source: Current Topics in Microbiology and Immunology - Category: Microbiology Tags: Curr Top Microbiol Immunol Source Type: research
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