Atshan Salman Sahab, Hamat Rukman Awang, Coolen Marco J L, Dykes Gary, Sekawi Zamberi, Mullins Benjamin J, Than Leslie Thian Lung, Abduljaleel Salwa A, Kicic Anthony
Department of Medical Science, Faculty of Dentistry, Basrah University, Basrah 61004, Iraq.
Department of Medical Microbiology, Faculty of Medicine and Health Sciences, Universiti Putra Malaysia, Serdang 43400, Selangor, Malaysia.
Antibiotics (Basel). 2021 Jan 3;10(1):39. doi: 10.3390/antibiotics10010039.
() infections are notoriously complicated by the ability of the organism to grow in biofilms and are difficult to eradicate with antimicrobial therapy. The purpose of the current study was to clarify the influence of sub-inhibitory concentrations (sub-MICs) of daptomycin and tigecycline antibiotics on biofilm adhesion factors and exoproteins expressions by clinical isolates. Six clinical isolates representing positive biofilm clones (3 methicillin-sensitive (MSSA) and 3 methicillin-resistant (MRSA)) were grown with sub-MICs (0.5 MIC) of two antibiotics (daptomycin and tigecycline) for 12 h of incubation. RNA extracted from culture pellets was used via relative quantitative real-time-PCR (qRT-PCR) to determine expression of specific adhesion (, , , , , , , ) and biofilm () genes. To examine the effect of sub-MIC of these antibiotics on the expression of extracellular proteins, samples from the culture supernatants of six isolates were collected after 12 h of treatment with or without tigecycline in order to profile protein production via 2D gel sodium dodecyl sulfate-polyacrylamide gel electrophoresis (2D gel-SDS-PAGE). Sub-MIC treatment of all clinical MRSA and MSSA strains with daptomycin or tigecycline dramatically induced or suppressed , , , , , , , , and gene expression. Furthermore, sub-MIC use of tigecycline significantly reduced the total number of separated protein spots across all the isolates, as well as decreasing production of certain individual proteins. Collectively, this study showed very different responses in terms of both gene expression and protein secretion across the various isolates. In addition, our results suggest that sub-MIC usage of daptomycin and tigecycline could signal virulence induction by via the regulation of biofilm adhesion factor genes and exoproteins. If translating findings to the clinical treatment of , the therapeutic regimen should be adapted depending on antibiotic, the virulence factor and strain type.
由于该微生物具有在生物膜中生长的能力，（）感染 notoriously complicated，并且难以通过抗菌治疗根除。本研究的目的是阐明达托霉素和替加环素抗生素的亚抑菌浓度（亚 MIC）对临床分离株生物膜粘附因子和外蛋白表达的影响。将代表阳性生物膜克隆的 6 株临床分离株（3 株甲氧西林敏感（MSSA）和 3 株甲氧西林耐药（MRSA））与两种抗生素（达托霉素和替加环素）的亚 MIC（0.5 MIC）一起培养 12 小时。从培养沉淀物中提取的 RNA 通过相对定量实时 PCR（qRT-PCR）用于确定特定粘附（，，，，，，，）和生物膜（）基因的表达。为了检查这些抗生素的亚 MIC 对细胞外蛋白表达的影响，在用或不用替加环素处理 12 小时后，收集来自 6 株分离株培养上清液的样品，以便通过二维凝胶十二烷基硫酸钠 - 聚丙烯酰胺凝胶电泳（二维凝胶 - SDS-PAGE）分析蛋白质产生情况。用达托霉素或替加环素对所有临床 MRSA 和 MSSA 菌株进行亚 MIC 处理，显著诱导或抑制了，，，，，，，，和基因表达。此外，替加环素的亚 MIC 使用显著减少了所有分离株中分离的蛋白质斑点总数，以及某些个别蛋白质的产生。总体而言，本研究表明不同分离株在基因表达和蛋白质分泌方面有非常不同的反应。此外，我们的结果表明，达托霉素和替加环素的亚 MIC 使用可能通过生物膜粘附因子基因和外蛋白的调节来表明由诱导的毒力。如果将研究结果转化为的临床治疗，治疗方案应根据抗生素、毒力因子和菌株类型进行调整。
