Intercollegiate Faculty of Biotechnology, University of Gdansk and Medical University of Gdansk, Abrahama 58, 80-307, Gdansk, Poland.
Sci Rep. 2020 Oct 1;10(1):16354. doi: 10.1038/s41598-020-73409-1.
Staphylococcal enterotoxin B (SEB), encoded by the seb gene, is a virulence factor produced by Staphylococcus aureus that is involved mainly in food poisoning and is known to act as an aggravating factor in patients with atopic dermatitis. Research results in animal infection models support the concept that superantigens, including SEB contribute to sepsis and skin and soft tissue infections. In contrast to antibiotics, antimicrobial photodynamic inactivation (aPDI) is a promising method to combat both bacterial cells and virulence factors. The main aims of this research were to (1) select the most stable reference genes under sublethal aPDI treatments and (2) evaluate the impact of aPDI on seb. Two aPDI combinations were applied under sublethal conditions: rose bengal (RB) and green light (λ = 515 nm) and new methylene blue (NMB) and red light (λ = 632 nm). The stability of ten candidate reference genes (16S rRNA, fabD, ftsZ, gmk, gyrB, proC, pyk, rho, rpoB and tpiA) was evaluated upon aPDI using four software packages-BestKeeper, geNorm, NormFinder and RefFinder. Statistical analyses ranked ftsZ and gmk (RB + green light) and ftsZ, proC, and fabD (NMB + red light) as the most stable reference genes upon photodynamic treatment. Our studies showed downregulation of seb under both aPDI conditions, suggesting that aPDI could decrease the level of virulence factors.
葡萄球菌肠毒素 B（SEB）由 seb 基因编码，是金黄色葡萄球菌产生的一种毒力因子，主要与食物中毒有关，已知它是特应性皮炎患者的加重因素。动物感染模型的研究结果支持这样一种概念，即包括 SEB 在内的超抗原有助于脓毒症和皮肤及软组织感染。与抗生素不同，抗菌光动力灭活（aPDI）是一种有前途的方法，可以对抗细菌细胞和毒力因子。本研究的主要目的是：（1）选择亚致死剂量 aPDI 处理下最稳定的参考基因；（2）评估 aPDI 对 seb 的影响。在亚致死条件下应用了两种 aPDI 组合：孟加拉玫瑰红（RB）和绿光（λ=515nm）以及新亚甲基蓝（NMB）和红光（λ=632nm）。使用四个软件包-BestKeeper、geNorm、NormFinder 和 RefFinder，评估了 10 个候选参考基因（16S rRNA、fabD、ftsZ、gmk、gyrB、proC、pyk、rho、rpoB 和 tpiA）在 aPDI 下的稳定性。统计分析将 ftsZ 和 gmk（RB+绿光）和 ftsZ、proC 和 fabD（NMB+红光）列为光动力处理后最稳定的参考基因。我们的研究表明，在两种 aPDI 条件下 seb 下调，表明 aPDI 可以降低毒力因子的水平。
