The bacterium Staphylococcus aureus, which grows on healthy human skin, may cause diseases such as atopic dermatitis (AD). Treatment for such AD cases involves antibiotic use; however, alternate treatments are preferred owing to the development of antimicrobial resistance. This study aimed to characterize the novel bacteriophage SaGU1 as a potential agent for phage therapy to treat S. aureus infections. SaGU1 that infects S. aureus strains previously isolated from the skin of patients with AD was screened from sewage samples in Gifu, Japan. Its genome was sequenced and analyzed using bioinformatics tools, and the morphology, lytic activity, stability, and host range of the phage were determined. The SaGU1 genome consisted of 140,909 bp with an average GC content of 30.2%. The viral chromosome contained putative 225 protein-coding genes and four tRNA genes, carrying neither toxic nor antibiotic resistance genes. Electron microscopy analysis revealed that SaGU1 belongs to the Myoviridae family. Stability tests showed that SaGU1 was heat-stable under physiological and acidic conditions. Host-range testing revealed that SaGU1 could infect a broad range of S. aureus clinical isolates present on the skin of patients with AD, whereas it did not kill strains of Staphylococcus epidermidis, which are symbiotic bacteria in the human skin microbiota. Our data suggest that SaGU1 is a potential candidate for developing a phage therapy to treat AD caused by pathogenic S. aureus.

中文翻译：

---

新型噬菌体SaGU1的分离和鉴定，该噬菌体感染了特应性皮炎患者的金黄色葡萄球菌临床分离株

在健康的人类皮肤上生长的金黄色葡萄球菌细菌可能引起诸如特应性皮炎（AD）的疾病。对这类AD病例的治疗涉及抗生素的使用；但是，由于产生了抗药性，因此首选替代疗法。这项研究旨在表征新型噬菌体SaGU1作为噬菌体治疗金黄色葡萄球菌感染的潜在药物。从日本岐阜市的污水样品中筛选出感染先前从AD患者皮肤中分离出的金黄色葡萄球菌菌株的SaGU1。使用生物信息学工具对其基因组进行测序和分析，然后确定噬菌体的形态，裂解活性，稳定性和宿主范围。SaGU1基因组由140,909 bp组成，平均GC含量为30.2％。病毒染色体包含推定的225个蛋白质编码基因和4个tRNA基因，既不携带毒性也不具有抗生素抗性基因。电子显微镜分析表明，SaGU1属于Myoviridae家族。稳定性测试表明，SaGU1在生理和酸性条件下均具有热稳定性。宿主范围测试显示，SaGU1可以感染AD患者皮肤上存在的多种金黄色葡萄球菌临床分离株，而它并没有杀死表皮葡萄球菌菌株，后者是人类皮肤微生物群中的共生细菌。我们的数据表明SaGU1是开发噬菌体疗法来治疗由致病性金黄色葡萄球菌引起的AD的潜在候选人。稳定性测试表明，SaGU1在生理和酸性条件下均具有热稳定性。宿主范围测试显示，SaGU1可以感染AD患者皮肤上存在的多种金黄色葡萄球菌临床分离株，而它并没有杀死表皮葡萄球菌菌株，后者是人类皮肤微生物群中的共生细菌。我们的数据表明SaGU1是开发噬菌体疗法来治疗由致病性金黄色葡萄球菌引起的AD的潜在候选人。稳定性测试表明，SaGU1在生理和酸性条件下均具有热稳定性。宿主范围测试显示，SaGU1可以感染AD患者皮肤上存在的多种金黄色葡萄球菌临床分离株，而它并没有杀死表皮葡萄球菌菌株，后者是人类皮肤微生物群中的共生细菌。我们的数据表明SaGU1是开发噬菌体疗法来治疗由致病性金黄色葡萄球菌引起的AD的潜在候选人。