Melles Damian C, Gorkink Raymond F J, Boelens Hélène A M, Snijders Susan V, Peeters Justine K, Moorhouse Michael J, van der Spek Peter J, van Leeuwen Willem B, Simons Guus, Verbrugh Henri A, van Belkum Alex
University Medical Center Rotterdam, Department of Medical Microbiology and Infectious Diseases, Room L-313, Dr Molewaterplein 40, 3015 GD Rotterdam, The Netherlands.
J Clin Invest. 2004 Dec;114(12):1732-40. doi: 10.1172/JCI23083.
The population structure of Staphylococcus aureus carried by healthy humans was determined using a large strain collection of nonclinical origin (n = 829). High-throughput amplified fragment length polymorphism (AFLP) analysis revealed 3 major and 2 minor genetic clusters of S. aureus, which were corroborated by multilocus sequence typing. Major AFLP cluster I comprised 44.4% of the carriage isolates and showed additional heterogeneity whereas major AFLP groups II and III presented 2 homogeneous clusters, including 47.3% of all carriage isolates. Coanalysis of invasive S. aureus strains and epidemic methicillin-resistant S. aureus (MRSA) revealed that all major clusters contained invasive and multiresistant isolates. However, clusters and subclusters with overrepresentation of invasive isolates were also identified. Bacteremia in elderly adults, for instance, was caused by a IVa cluster-derived strain significantly more often than by strains from other AFLP clusters. Furthermore, expansion of multiresistant clones or clones associated with skin disease (impetigo) was detected, which suggests that epidemic potential is present in pathogenic strains of S. aureus. In addition, the virulence gene encoding Panton-Valentine leukocidin was significantly enriched in S. aureus strains causing abscesses and arthritis in comparison with the carriage group. We provide evidence that essentially any S. aureus genotype carried by humans can transform into a life-threatening human pathogen but that certain clones are more virulent than others.
利用大量非临床来源的菌株（n = 829）确定了健康人携带的金黄色葡萄球菌的种群结构。高通量扩增片段长度多态性（AFLP）分析揭示了金黄色葡萄球菌的3个主要和2个次要遗传簇，多位点序列分型证实了这一点。主要的AFLP簇I包含44.4%的携带菌株，并显示出额外的异质性，而主要的AFLP组II和III呈现出2个同质簇，包括所有携带菌株的47.3%。对侵袭性金黄色葡萄球菌菌株和流行性耐甲氧西林金黄色葡萄球菌（MRSA）的联合分析表明，所有主要簇都包含侵袭性和多重耐药菌株。然而，也鉴定出了侵袭性菌株过度富集的簇和亚簇。例如，老年人的菌血症由IVa簇衍生菌株引起的频率明显高于其他AFLP簇的菌株。此外，检测到多重耐药克隆或与皮肤病（脓疱病）相关的克隆的扩张，这表明金黄色葡萄球菌的致病菌株具有流行潜力。此外，与携带组相比，编码杀白细胞素的毒力基因在引起脓肿和关节炎的金黄色葡萄球菌菌株中显著富集。我们提供的证据表明，人类携带的基本上任何金黄色葡萄球菌基因型都可以转化为危及生命的人类病原体，但某些克隆比其他克隆更具毒力。
