Title |
Characteristics of the community-genotype sequence type 72 methicillin-resistant Staphylococcus aureus isolates that underlie their persistence in hospitals |
Author |
Eun-Jeong Joo1, Ji-Young Choi2, Doo Ryeon Chung3,4, Jae-Hoon Song3,4, and Kwan Soo Ko2,4* |
Address |
1Division of Infectious Diseases, Department of Internal Medicine, Kangbuk Samsung Hospital, Sungkyunkwan University School of Medicine, Seoul 03181, Republic of Korea, 2Department of Molecular Cell Biology, Sungkyunkwan University School of Medicine, Suwon 16419, Republic of Korea, 3Division of Infectious Diseases, Samsung Medical Center,Sungkyunkwan University School of Medicine, Seoul 06351, Republic of Korea , 4Asia-Pacific Foundation for Infectious Diseases (APFID), Seoul 06351,Republic of Korea |
Bibliography |
Journal of Microbiology, 54(6),445-450, 2016,
|
DOI |
10.1007/s12275-016-6157-x
|
Key Words |
CA-MRSA, ST72, ST5, ST239, healthcare-associated
infection, skin and soft tissue infections |
Abstract |
Panton-Valentine leukocidin-negative methicillin-resistant
Staphylococcus aureus (MRSA) clone ST72, known as a major
community-associated MRSA in Korea, has emerged as an
important pathogen in hospitals. To understand bacterial
properties that underlie transformation of this clone into a
nosocomial pathogen, we compared characteristics of the
community-genotype ST72 MRSA isolates with those of ST5
and ST239 MRSA, which have been predominant nosocomial
MRSA clones in Korea. Several genes associated with
adhesion and virulence were absent or rarely found in ST72
isolates. Many ST72 isolates (70.1%) belonged to agr group I,
but the agr group of other ST72 isolates could not be determined.
As indicated by δ-hemolysin production, ST72 isolates
expressed fully functional agr, whereas agr dysfunction
was observed in ST5 and ST239 isolates. In the biofilm formation
assay, no upregulation of biofilm-forming activity
of ST72 MRSA was detected. However, ST72 isolates demonstrated
persistence under hypotonic and desiccating conditions
(survival rates 72.3% and 33.9%, respectively), which
was similar to characteristics of ST5 or ST239 isolates. ST72-
MRSA isolates showed low virulence, but properties of their
functional agr system could facilitate their spread in hospitals.
In conclusion, tolerance to stressful environments, e.g., hypotonic
and dry conditions, may also contribute to survival
of the community-associated MRSA clones in healthcare
facilities. |