Department of Orthopedics, West China Hospital, Sichuan University, No. 37 Guoxue Alley, Chengdu, 610041, Sichuan, People's Republic of China.
State Key Laboratory of Oral Diseases, Department of Preventive Dentistry, West China Hospital of Stomatology, Sichuan University, No. 14 Renmin South Road, Chengdu City, 610041, Sichuan, China.
J Orthop Surg Res. 2019 Sep 6;14(1):305. doi: 10.1186/s13018-019-1356-x.
Staphylococcus aureus (S. aureus) has the potential to opportunistically cause infectious diseases, including osteomyelitis, skin infections, pneumonia, and diarrhea. We previously reported that ASyycG RNA reduced the transcripts of virulent genes, and biofilm formation of S. aureus. Currently, graphene oxide (GO) nanosheets are used to efficiently deliver nucleic acids with favorable biocompatibility.
In the current study, a GO-based recombinant pDL278 ASyycG vector transformation strategy was developed. The particle size distributions and zeta-potential of the GO-PEI-based ASyycG were evaluated. The ASyycG plasmids were labeled with gene-encoding enhanced green fluorescent protein (ASyycG-eGFP). Quantitative real-time PCR assays were performed to investigate the expression of yycF/G/H and icaADB genes. Biofilm biomass and bacterial viability of S. aureus were evaluated by scanning electron microscopy and confocal laser scanning microscopy. We found that the expression of the yycG gene was inversely correlated with levels of the ASyycG transcripts and that the GO-PEI-ASyycG strain had the lowest expression of biofilm organization-associated genes.
The results showed that the GO-based strategy significantly increased ASyycG transformation as a delivery system compared to the conventional competence-stimulating peptide strategy. Furthermore, GO-PEI-ASyycG suppressed bacterial biofilm aggregation and improved bactericidal effects on S. aureus after 24 h biofilm establishment.
Our findings demonstrated that nano-GO with antisense yycG RNA is a more effective and relatively stable strategy for the management of S. aureus infections.
金黄色葡萄球菌（S. aureus）具有机会性引发传染病的潜力，包括骨髓炎、皮肤感染、肺炎和腹泻。我们之前报道过，ASyycG RNA 减少了 S. aureus 毒力基因和生物膜形成的转录物。目前，氧化石墨烯（GO）纳米片被用于高效递送达良好生物相容性的核酸。
在本研究中，开发了基于 GO 的重组 pDL278 ASyycG 载体转化策略。评估了基于 GO-PEI 的 ASyycG 的粒径分布和 ζ-电位。将 ASyycG 质粒标记有编码增强型绿色荧光蛋白的基因（ASyycG-eGFP）。通过定量实时 PCR 检测分析 yycF/G/H 和 icaADB 基因的表达。通过扫描电子显微镜和共聚焦激光扫描显微镜评估金黄色葡萄球菌生物膜生物量和细菌活力。我们发现，yycG 基因的表达与 ASyycG 转录物的水平呈负相关，并且 GO-PEI-ASyycG 菌株的生物膜组织相关基因表达最低。
结果表明，与传统的刺激肽竞争策略相比，基于 GO 的策略作为递送系统显著增加了 ASyycG 的转化。此外，GO-PEI-ASyycG 抑制了 24 小时生物膜形成后金黄色葡萄球菌生物膜聚集，并提高了杀菌效果。
我们的研究结果表明，纳米 GO 与反义 yycG RNA 是一种更有效且相对稳定的管理金黄色葡萄球菌感染的策略。
