Comparative analysis of the virulence characteristics of epidemic methicillin–resistant Staphylococcus aureus (MRSA) strains isolated from Chinese children: ST59 MRSA highly expresses core gene–encoded toxin. Issue 2 (25th May 2013)

• Record Type: Journal Article
• Authors: Li, Shipeng; Sun, Jing; Zhang, Jianzhong; Li, Xiangmei; Tao, Xiaoxia; Wang, Lijuan; Sun, Mingjiao; Liu, Yingchao; Li, Juan; Qiao, Yanhong; Yu, Sangjie; Yao, Kaihu; Yang, Yonghong; Shen, Xuzhuang
• Is Part Of: Apmis. Volume 122:Issue 2(2014:Feb.)
• Page Start: 101
• Page End: 114
• Publication Date: 2013-05-25
• Subjects: Pathology -- Periodicals; Microbiology -- Periodicals; Immunology -- Periodicals; 572
• DOI: 10.1111/apm.12105
• Languages: English
• ISSNs: 0903-4641

Abstract

<abstract abstract-type="main" id="apm12105-abs-0001"> <title> <x xml:space="preserve">Abstract</x> </title> <p>This study aims to investigate the prevalence of a novel cell wall‐anchored protein gene, <italic>sasX</italic>, and to obtain information on the genetic basis for the pathogenic potential of the MRSA strains isolated from Chinese children. The molecular and virulence characteristics of the clinical strains were analyzed. Twenty‐two sequence types (STs) were obtained, with six epidemic clones ST59, ST239, ST1, ST910, ST88, and ST338 accounting for 35.8, 22, 6.6, 6.6, 5.3, and 4.1% respectively. The expression levels of <italic>hla</italic>, <italic> psm</italic>α, and <italic>RNAIII</italic> were higher in ST59 than in other STs (p < 0.05). The <italic>sasX</italic> gene was detected in 26 (10.7%) MRSA isolates. ST239‐MRSA‐SCCmecIII‐t037 (61.5%) was the predominant <italic>sasX</italic>‐positive MRSA clone. The expressions of <italic>PSMα</italic> and <italic>RNAIII</italic> were higher in <italic>sasX</italic>‐positive ST239 isolates than in <italic>sasX</italic>‐negative ST239 ones (p<italic> </italic>< 0.01). Notably, the percentage of invasive infection in infections caused by <italic>sasX</italic>‐positive ST239 MRSA was higher than that by <italic>sasX</italic>‐negative ST239 MRSA (p<italic> </italic>= 0.008). This study indicated that ST59 was the predominant clone in the MRSA isolates obtained from Chinese children and might have stronger pathogenic potential. The prevalence of the <italic>sasX</italic> gene in the MRSA isolates from children was relatively low. Furthermore, the <italic>sasX</italic> gene might be related to the expressions of <italic>PSMα</italic> and <italic>RNAIII</italic> and infection invasiveness.</p> </abstract>