Department of Biomedicine and Biotechnology, University of Alcalá, Alcalá de Henares, Madrid, Spain.
Microbiology Service, Hospital Universitario Príncipe de Asturias, Alcalá-Meco, Alcalá de Henares, Madrid, Spain.
PLoS One. 2020 Mar 12;15(3):e0230031. doi: 10.1371/journal.pone.0230031. eCollection 2020.
We characterised 80 Staphylococcus aureus strains isolated from human patients with SSTIs at a rural hospital in Ethiopia. Susceptibility to antibiotic of all strains was tested. The MLST method was used to type and a phylogenetic analysis was conducted employing the sequences of 7 housekeeping genes. PCR amplification was used to investigate the presence of the following virulence genes in all strains: hla (α-haemolysin), tstH (toxic shock syndrome toxin), luk PV (Panton-Valentine leukocidin), fnbA (fibronectin binding protein A) and mecA (methicillin resistance). Most of the strains were resistant to penicillin and ampicillin, but only 3 strains were resistant to oxacillin, and 1 of them was a true MRSA. The MLST results showed a high diversity of sequence types (ST), 55% of which were new, and ST152 was the most prevalent. A phylogeny study showed that many of the new STs were phylogenetically related to other previously described STs, but bore little relationship to the only ST from Ethiopia described in the database. Virulence gene detection showed a high prevalence of strains encoding the hla, fnbA and pvl genes (98.77%, 96.3% and 72.84%, respectively), a low prevalence of the tst gene (13.58%) and a markedly low prevalence of MRSA (1.25%). S. aureus strains isolated from patients in a rural area in Ethiopia showed low levels of antibiotic resistance, except to penicillin. Moreover, this study reveals new STs in Eastern Africa that are phylogenetically related to other previously described STs, and confirm the high prevalence of the pvl gene and the low prevalence of MRSA on the continent.
我们从埃塞俄比亚农村医院患有 SSTIs 的人类患者中分离出 80 株金黄色葡萄球菌菌株，并对所有菌株的抗生素敏感性进行了测试。采用 MLST 方法对菌株进行分型，并对 7 种看家基因序列进行系统发育分析。采用 PCR 扩增技术检测所有菌株中以下毒力基因的存在情况：hla（α-溶血素）、tstH（中毒性休克综合征毒素）、luk PV（潘顿-瓦伦丁白细胞素）、fnbA（纤维结合蛋白 A）和 mecA（耐甲氧西林基因）。大多数菌株对青霉素和氨苄西林耐药，但只有 3 株对苯唑西林耐药，其中 1 株为真正的耐甲氧西林金黄色葡萄球菌。MLST 结果显示，序列型（ST）高度多样化，其中 55%为新 ST，ST152 最为流行。系统发育研究表明，许多新 ST 与其他先前描述的 ST 具有亲缘关系，但与数据库中描述的来自埃塞俄比亚的唯一 ST 关系不大。毒力基因检测显示，携带 hla、fnbA 和 pvl 基因的菌株流行率较高（分别为 98.77%、96.3%和 72.84%），tst 基因流行率较低（13.58%），MRSA 流行率明显较低（1.25%）。从埃塞俄比亚农村地区患者中分离出的金黄色葡萄球菌对青霉素以外的抗生素的耐药性较低。此外，本研究揭示了东非地区新的 ST，这些 ST 与其他先前描述的 ST 具有亲缘关系，并证实了该大陆 pvl 基因的高流行率和 MRSA 的低流行率。
