scholarly journals Genetic Analysis of a Vancomycin-Resistant Staphylococcus aureus Strain Isolated in Iran

mBio ◽  
2012 ◽  
Vol 3 (6) ◽  
Author(s):  
Amir Azimian ◽  
Seyed Asghar Havaei ◽  
Hosein Fazeli ◽  
Mahmood Naderi ◽  
Kiarash Ghazvini ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Genetic Analysis ◽  
Aureus Strain ◽  
Vancomycin Resistant

scholarly journals Genetic Characterization of Methicillin Resistant and Sensitive, Vancomycin Intermediate Staphylococcus aureus Strains Isolated from Different Iranian Hospitals

2012 ◽  
Vol 2012 ◽  
pp. 1-6 ◽  
Author(s):  
Seyed Asghar Havaei ◽  
Amir Azimian ◽  
Hosein Fazeli ◽  
Mahmood Naderi ◽  
Kiarash Ghazvini ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Genetic Analysis ◽  
Clinical Samples ◽  
Different Types ◽  
Health Care Policies ◽  
Global Health Care ◽  
Vancomycin Resistant ◽  
Epidemiological Evaluation ◽  
Mrsa Strains

Background. Global concerns have been raised due to upward trend of Vancomycin Intermediate Staphylococcus aureus (VISA) and Vancomycin Resistant Staphylococcus aureus (VRSA) reports which mean casting doubt on the absolute effectiveness of the last line of antibiotic treatment for S. aureus, vancomycin. Hence, epidemiological evaluation can improve global health care policies. Methodology. 171 Isolates of Staphylococcus aureus were collected from different types of clinical samples in selected hospitals in Isfahan, Mashhad, and Tehran, Iran. Then, they were evaluated by agar screening, disk diffusion, and MIC method to determine their resistance to vancomycin and methicillin. The isolated VISA strains were then confirmed with genetic analysis by the evaluation of mecA and vanA genes, SCCmec, agr, and spa type, and also toxin profiles. MLST was also performed. Results and Conclusion. Our data indicated that 67% of isolated S. aureus strains were resistant to methicillin. Furthermore, five isolates (2.9%) had intermediate resistance to vancomycin (VISA). In contrast to usual association of VISA with MRSA strains, we found two isolates of MSSA-VISA. Therefore, our data suggests a probable parallel growing trend of VISA towards MSSA, along with MRSA strains. However, more samples are required to confirm these primarily data. Moreover, genetic analysis of the isolated VISA strains revealed that these strains are endemic Asian clones.

scholarly journals Derivatives of a Vancomycin-Resistant Staphylococcus aureus Strain Isolated at Hershey Medical Center

2004 ◽  
Vol 48 (12) ◽  
pp. 4762-4765 ◽  
Author(s):  
Bülent Bozdogan ◽  
Lois Ednie ◽  
Kim Credito ◽  
Klaudia Kosowska ◽  
Peter C. Appelbaum
Keyword(s):  
Staphylococcus Aureus ◽  
Genetic Relatedness ◽  
Medical Center ◽  
Aureus Strain ◽  
Original Culture ◽  
Vancomycin Mics ◽  
Allele Variant ◽  
Vancomycin Resistant ◽  
High Level ◽  
Derivatives Of

ABSTRACT Antimicrobial susceptibilities and genetic relatedness of the vancomycin-resistant Staphylococcus aureus strain (VRSA) isolated at Hershey, Pa. (VRSA Hershey), and its vancomycin-susceptible and high-level-resistant derivatives were studied and compared to 32 methicillin-resistant S. aureus strains (MRSA) isolated from patients and medical staff in contact with the VRSA patient. Derivatives of VRSA were obtained by subculturing six VRSA colonies from the original culture with or without vancomycin. Ten days of drug-free subculture caused the loss of vanA in two vancomycin-susceptible derivatives for which vancomycin MICs were 1 to 4 μg/ml. Multistep selection of three VRSA clones with vancomycin for 10 days increased vancomycin MICs from 32 to 1,024 to 2,048 μg/ml. MICs of teicoplanin, dalbavancin, and oritavancin were also increased from 4, 0.5, and 0.12 to 64, 1, and 32 μg/ml, respectively. Pulsed-field gel electrophoresis (PFGE) and multilocus sequence typing analysis indicated that VRSA Hershey was the vanA-acquired variety of a common MRSA clone in our hospital with sequence type 5 (ST5). Three of five vancomycin-intermediate S. aureus strains tested from geographically different areas were also ST5, and the Michigan VRSA was ST371, a one-allele variant of ST5. Derivatives of VRSA Hershey had differences in PFGE profiles and the size of SmaI fragment that carries the vanA gene cluster, indicating instability of this cluster in VRSA Hershey. However induction with vancomycin increased glycopeptide MICs and stabilized the resistance.

scholarly journals Increase in glutamine-non-amidated muropeptides in the peptidoglycan of vancomycin-resistant Staphylococcus aureus strain Mu50.

1998 ◽  
Vol 42 (3) ◽  
pp. 315-320 ◽  
Author(s):  
H. Hanaki ◽  
H. Labischinski ◽  
Y. Inaba ◽  
N. Kondo ◽  
H. Murakami ◽  
...  
Keyword(s):  
Staphylococcus Aureus ◽  
Aureus Strain ◽  
Vancomycin Resistant
Sign in / Sign up

Export Citation Format

Share Document