scholarly journals Molecular typing of community-acquired methicillin-resistant Staphylococcus aureus isolated from 2- to 6-year old children by staphylococcal protein A and agr typing in Isfahan, Iran

2021 ◽  
Vol 10 (1) ◽  
pp. 3
Author(s):  
Davood Azadi ◽  
Sina Mobasherizadeh ◽  
Hasan Shojaei ◽  
SeyedAsghar Havaei ◽  
Behrooz Ataei ◽  
...  
2017 ◽  
Vol 80 (3) ◽  
pp. 476-481 ◽  
Author(s):  
V. Murugadas ◽  
C. Joseph Toms ◽  
Sara A. Reethu ◽  
K. V. Lalitha

ABSTRACT Methicillin-resistant Staphylococcus aureus (MRSA) has been a global health concern since the 1960s, and isolation of this pathogen from food-producing animals has been increasing. However, little information is available on the prevalence of MRSA and its clonal characteristics in seafood and the aquatic environment. In this study, 267 seafood and aquatic environment samples were collected from three districts of Kerala, India. Staphylococcal protein A (spa) typing and multilocus sequence typing (MLST) was performed for 65 MRSA strains isolated from 20 seafood and aquatic environment samples. The MRSA clonal profiles were t657-ST772, t002-ST5, t334-ST5, t311-ST5, t121-ST8, t186-ST88, t127-ST1, and two non-spa assignable strains. Whole spa gene sequence analysis along with MLST confirmed one strain as t711-ST6 and another as a novel MRSA clone identified for the first time in seafood and the aquatic environment with a t15669 spa type and a new MLST profile of ST420-256-236-66-82-411-477. The MRSA strains were clustered into five clonal complexes based on the goeBURST algorithm, indicating high diversity among MRSA strains in seafood and the aquatic environment. The novel clone formed a separate clonal complex with matches to three loci. This study recommends large-scale spa typing and MLST of MRSA isolates from seafood and the aquatic environment to determine the prevalence of new MRSA clones. This monitoring process can be useful for tracing local spread of MRSA isolates into the seafood production chain in a defined geographical area.


2010 ◽  
Vol 207 (9) ◽  
pp. 1863-1870 ◽  
Author(s):  
Hwan Keun Kim ◽  
Alice G. Cheng ◽  
Hye-Young Kim ◽  
Dominique M. Missiakas ◽  
Olaf Schneewind

The current epidemic of hospital- and community-acquired methicillin-resistant Staphylococcus aureus (MRSA) infections has caused significant human morbidity, but a protective vaccine is not yet available. Prior infection with S. aureus is not associated with protective immunity. This phenomenon involves staphylococcal protein A (SpA), an S. aureus surface molecule that binds to Fcγ of immunoglobulin (Ig) and to the Fab portion of VH3-type B cell receptors, thereby interfering with opsonophagocytic clearance of the pathogen and ablating adaptive immune responses. We show that mutation of each of the five Ig-binding domains of SpA with amino acid substitutions abolished the ability of the resulting variant SpAKKAA to bind Fcγ or Fab VH3 and promote B cell apoptosis. Immunization of mice with SpAKKAA raised antibodies that blocked the virulence of staphylococci, promoted opsonophagocytic clearance, and protected mice against challenge with highly virulent MRSA strains. Furthermore, SpAKKAA immunization enabled MRSA-challenged mice to mount antibody responses to many different staphylococcal antigens.


Toxins ◽  
2020 ◽  
Vol 13 (1) ◽  
pp. 14
Author(s):  
Thamiris Santana Machado ◽  
Felipe Ramos Pinheiro ◽  
Lialyz Soares Pereira Andre ◽  
Renata Freire Alves Pereira ◽  
Reginaldo Fernandes Correa ◽  
...  

Hospitalizations related to Methicillin-resistant Staphylococcus aureus (MRSA) are frequent, increasing mortality and health costs. In this way, this study aimed to compare the genotypic and phenotypic characteristics of MRSA isolates that colonize and infect patients seen at two hospitals in the city of Niterói—Rio de Janeiro, Brazil. A total of 147 samples collected between March 2013 and December 2015 were phenotyped and genotyped to identify the protein A (SPA) gene, the mec staphylococcal chromosomal cassette (SCCmec), mecA, Panton-Valentine Leucocidin (PVL), icaC, icaR, ACME, and hla virulence genes. The strength of biofilm formation has also been exploited. The prevalence of SCCmec type IV (77.1%) was observed in the colonization group; however, in the invasive infection group, SCCmec type II was prevalent (62.9%). The Multilocus Sequence Typing (MLST), ST5/ST30, and ST5/ST239 analyses were the most frequent clones in colonization, and invasive infection isolates, respectively. Among the isolates selected to assess the ability to form a biofilm, 51.06% were classified as strong biofilm builders. Surprisingly, we observed that isolates other than the Brazilian Epidemic Clone (BEC) have appeared in Brazilian hospitals. The virulence profile has changed among these isolates since the ACME type I and II genes were also identified in this collection.


Sign in / Sign up

Export Citation Format

Share Document