scholarly journals Expansion of a Plasmid Classification System for Gram-Positive Bacteria and Determination of the Diversity of Plasmids in Staphylococcus aureus Strains of Human, Animal, and Food Origins

2012 ◽  
Vol 78 (16) ◽  
pp. 5948-5955 ◽  
Author(s):  
Carmen Lozano ◽  
Lourdes García-Migura ◽  
Carmen Aspiroz ◽  
Myriam Zarazaga ◽  
Carmen Torres ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Classification System ◽  
Gel Electrophoresis ◽  
Pulsed Field Gel Electrophoresis ◽  
Content Type ◽  
Plasmid Content ◽  
Gram Positive Bacteria ◽  
Human Animal ◽  
Different Origins

ABSTRACTAn expansion of a previously described plasmid classification was performed and used to reveal the plasmid content of a collection of 92Staphylococcus aureusstrains of different origins.repgenes of other genera were detected inStaphylococcus. S1 pulsed-field gel electrophoresis (PFGE) hybridizations were performed with 18 representativeS. aureusstrains, and a high number of plasmids of different sizes and organizations were detected.

scholarly journals Comparison of Virulence Gene Identification, Ribosomal Spacer PCR, and Pulsed-Field Gel Electrophoresis for Typing of Staphylococcus aureus Strains Isolated from Cases of Subclinical Bovine Mastitis in the United States

2016 ◽  
Vol 54 (7) ◽  
pp. 1871-1876 ◽  
Author(s):  
Pamela R. F. Adkins ◽  
John R. Middleton ◽  
Lawrence K. Fox
Keyword(s):  
United States ◽  
Staphylococcus Aureus ◽  
Gel Electrophoresis ◽  
Virulence Gene ◽  
The United States ◽  
Pulsed Field Gel Electrophoresis ◽  
Gene Identification ◽  
Content Type ◽  
Pulsed Field

Staphylococcus aureusis one of the most important pathogens causing contagious mastitis in dairy cattle worldwide. The objectives of this study were to determine if recently describedS. aureusgenotype B was present among previously characterized isolates from cases of bovine intramammary infection in the United States and to compare pulsed-field gel electrophoresis (PFGE) to the combination of ribosomal spacer PCR (RS-PCR) and virulence gene identification for typing ofS. aureusstrains. The hypothesis was that isolates that were previously characterized as contagious would be identified as genotype B and that the results of the two strain-typing methods would be comparable. Isolates were selected from a collection ofS. aureusisolates from eight dairy farms. Mammary quarter milk somatic cell count (SCC) andN-acetyl-β-d-gluconaminidase (NAGase) activity data were known and used to evaluate strain pathogenicity. RS-PCR was performed with conventional gel electrophoresis, and PCR was used for toxin gene identification. RS-PCR patterns were associated with a specific virulence gene pattern, as previously reported. Five RS-PCR banding patterns were identified. None of the isolates were characterized as genotype B. No association between RS-PCR types and milk SCC was found; however, NAGase activity was significantly higher in milk from mammary glands infected with RS-PCR banding type 1 (RSP type 1) than in milk from those infected with RSP type 2. The discriminatory power values were 1.0 and 0.46 for PFGE and RS-PCR, respectively. These data suggest that genotype B may have a limited geographic distribution and that PFGE is more discriminatory than RS-PCR performed with conventional gel electrophoresis for typing ofS. aureusisolates of bovine origin.

scholarly journals Pulsed-Field Gel Electrophoresis and PCR Characterization of Environmental Vibrio parahaemolyticus Strains of Different Origins

2011 ◽  
Vol 77 (17) ◽  
pp. 6301-6304 ◽  
Author(s):  
E. Suffredini ◽  
C. Lopez-Joven ◽  
L. Maddalena ◽  
L. Croci ◽  
A. Roque
Keyword(s):  
Gel Electrophoresis ◽  
Vibrio Parahaemolyticus ◽  
Genetic Relationships ◽  
Pulsed Field Gel Electrophoresis ◽  
Environmental Isolates ◽  
Content Type ◽  
Pulsed Field ◽  
Intraspecies Variability ◽  
Different Origins

ABSTRACTThe present study used pulsed-field gel electrophoresis (PFGE) characterization to examine the intraspecies variability and genetic relationships among environmental isolates ofVibrio parahaemolyticusfrom different European countries. This is first study performed on environmentalV. parahaemolyticusthat included more than one European country.

scholarly journals Association of Vancomycin MIC and Molecular Characteristics with Clinical Outcomes in Methicillin-Susceptible Staphylococcus aureus Acute Hematogenous Osteoarticular Infections in Children

2018 ◽  
Vol 62 (5) ◽  
Author(s):  
Eric Y. Kok ◽  
Jesus G. Vallejo ◽  
Lauren M. Sommer ◽  
Louie Rosas ◽  
Sheldon L. Kaplan ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Clinical Outcomes ◽  
Gel Electrophoresis ◽  
Methicillin Resistance ◽  
Pulsed Field Gel Electrophoresis ◽  
Molecular Characteristics ◽  
Content Type ◽  
Group 4 ◽  
Osteoarticular Infections ◽  
Vancomycin Mics

ABSTRACT Strains of methicillin-resistant Staphylococcus aureus (MRSA), particularly those belonging to the USA300 pulsotype, have been well described to cause severe osteoarticular infections (OAIs). A vancomycin MIC of ≥1.5 μg/ml has been demonstrated to contribute to disease severity in adults with MRSA and even methicillin-susceptible S. aureus (MSSA) bacteremia. Little data exist describing the outcomes of MSSA OAIs in terms of molecular characteristics and vancomycin MIC. All patients/isolates were chosen from a surveillance study at Texas Children's Hospital (TCH). S. aureus OAI isolates were identified from 2011 to 2016 and subjected to vancomycin Etests, pulsed-field gel electrophoresis (PFGE), and PCR to determine Panton-Valentine leucocidin (PVL) production and agr group. Two hundred fifty-two cases of S. aureus OAI were identified; 183 cases were MSSA (72.6%). During the study period, a decrease in the proportion of cases secondary to MRSA was observed, declining from 37.8% to 15.9% ( P = 0.02). Of the MSSA isolates, 26.2% and 23.5% were USA300 and PVL positive, respectively. An increase in the proportion of MSSA isolates with a vancomycin MIC of ≥1.5 μg/ml occurred in the study period ( P = 0.004). In MSSA, an elevated vancomycin MIC was associated with multiple surgical procedures and venous thromboses, even when adjusting for empirical β-lactam use. An increase in vancomycin MIC was noted among isolates belonging to agr group 4 during the study period. Methicillin resistance is declining among S. aureus OAI isolates at TCH. Simultaneously, vancomycin Etest MICs are increasing among MSSA isolates. Vancomycin MICs of ≥2 μg/ml are associated with adverse clinical outcomes in MSSA irrespective of antibiotic choice, suggesting that this may be a surrogate for organism virulence.

scholarly journals Use of Pulsed-Field Gel Electrophoresis to Determine the Source of Methicillin-Resistant Staphylococcus aureus Bacteremia

2021 ◽  
Vol 13 (3) ◽  
pp. 602-610
Author(s):  
Eugene Y. H. Yeung ◽  
Ivan Gorn
Keyword(s):  
Staphylococcus Aureus ◽  
Gel Electrophoresis ◽  
Methicillin Resistant Staphylococcus Aureus ◽  
Epidemiological Studies ◽  
Pelvic Trauma ◽  
Pulsed Field Gel Electrophoresis ◽  
Bacterial Strains ◽  
Methicillin Resistant ◽  
Pulsed Field ◽  
Clinical Cases

Pulsed-field gel electrophoresis (PFGE) has historically been considered the gold standard in fingerprinting bacterial strains in epidemiological studies and outbreak investigations; little is known regarding its use in individual clinical cases. The current study detailed two clinical cases in which PFGE helped to determine the source of their methicillin-resistant Staphylococcus aureus (MRSA) bacteremia. Patient A was found to have MRSA bacteremia after trauma in her pelvic area. MRSA was also found in her groin but not in her nostril and rectum. PFGE was performed that showed variable bands of her MRSA isolates from blood and groin, suggestive of different strains of MRSA. Her MRSA bacteremia was determined to be unrelated to her pelvic trauma. Patient B was found to have MRSA bacteremia after colonoscopy. MRSA was also found in his nostril and rectum. PFGE was performed that showed variable bands of his MRSA isolates from blood and rectum but identical bands of MRSA isolates from his blood and nostril. His MRSA bacteremia was determined to be unrelated to his colonoscopy procedure. The current study demonstrates the use of PFGE to rule out the source of bacteremia in individual clinical cases.

scholarly journals The Phosphoenolpyruvate:Sugar Phosphotransferase System Is Involved in Sensitivity to the Glucosylated Bacteriocin Sublancin

2015 ◽  
Vol 59 (11) ◽  
pp. 6844-6854 ◽  
Author(s):  
C. V. Garcia De Gonzalo ◽  
E. L. Denham ◽  
R. A. T. Mars ◽  
J. Stülke ◽  
W. A. van der Donk ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Mechanism Of Action ◽  
Mode Of Action ◽  
Phosphotransferase System ◽  
Content Type ◽  
Gram Positive Bacteria ◽  
Distinct Mechanism ◽  
Genomic Studies ◽  
Increased Sensitivity ◽  
Bacterial Sensitivity

ABSTRACTThe mode of action of a group of glycosylated antimicrobial peptides known as glycocins remains to be elucidated. In the current study of one glycocin, sublancin, we identified the phosphoenolpyruvate:sugar phosphotransferase system (PTS) ofBacillusspecies as a key player in bacterial sensitivity. Sublancin kills several Gram-positive bacteria, such asBacillusspecies andStaphylococcus aureus, including methicillin-resistantS. aureus(MRSA). Unlike other classes of bacteriocins for which the PTS is involved in their mechanism of action, we show that the addition of PTS-requiring sugars leads to increased resistance rather than increased sensitivity, suggesting that sublancin has a distinct mechanism of action. Collectively, our present mutagenesis and genomic studies demonstrate that the histidine-containing phosphocarrier protein (HPr) and domain A of enzyme II (PtsG) in particular are critical determinants for bacterial sensitivity to sublancin.

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