Dhouib Rabeb, Vagenas Dimitrios, Hong Yaoqin, Verderosa Anthony D, Martin Jennifer L, Heras Begoña, Totsika Makrina
Institute of Health and Biomedical Innovation School of Biomedical Sciences Queensland University of Technology Herston QLD Australia.
Centre for Immunology and Infection Control School of Biomedical Sciences Queensland University of Technology Herston QLD Australia.
FASEB Bioadv. 2021 Feb 10;3(4):231-242. doi: 10.1096/fba.2020-00100. eCollection 2021 Apr.
Inhibition of the DiSulfide Bond (DSB) oxidative protein folding machinery, a major facilitator of virulence in Gram-negative bacteria, represents a promising antivirulence strategy. We previously developed small molecule inhibitors of DsbA from K-12 (EcDsbA) and showed that they attenuate virulence of Gram-negative pathogens by directly inhibiting multiple diverse DsbA homologues. Here we tested the evolutionary robustness of DsbA inhibitors as antivirulence antimicrobials against serovar Typhimurium under pathophysiological conditions in vitro. We show that phenylthiophene DsbA inhibitors slow . Typhimurium growth in minimal media, phenocopying . Typhimurium isogenic null mutants. Through passaging experiments, we found that DsbA inhibitor resistance was not induced under conditions that rapidly induced resistance to ciprofloxacin, an antibiotic commonly used to treat infections. Furthermore, no mutations were identified in the gene of inhibitor-treated . Typhimurium, and . Typhimurium virulence remained susceptible to DsbA inhibitors. Our work demonstrates that under in vitro pathophysiological conditions, DsbA inhibitors can have both antivirulence and antibiotic action. Importantly, our finding that DsbA inhibitors appear to be evolutionarily robust offers promise for their further development as next-generation antimicrobials against Gram-negative pathogens.
抑制二硫键（DSB）氧化蛋白折叠机制是一种很有前景的抗毒力策略，该机制是革兰氏阴性菌毒力的主要促进因素。我们之前开发了来自K-12的DsbA（EcDsbA）的小分子抑制剂，并表明它们通过直接抑制多种不同的DsbA同源物来减弱革兰氏阴性病原体的毒力。在这里，我们在体外病理生理条件下测试了DsbA抑制剂作为抗毒力抗菌剂针对鼠伤寒血清型的进化稳健性。我们表明苯并噻吩DsbA抑制剂减缓了鼠伤寒沙门氏菌在基本培养基中的生长，模拟了鼠伤寒沙门氏菌同基因缺失突变体的情况。通过传代实验，我们发现在快速诱导对环丙沙星（一种常用于治疗感染的抗生素）耐药的条件下，不会诱导产生对DsbA抑制剂的耐药性。此外，在经抑制剂处理的鼠伤寒沙门氏菌的基因中未发现突变，并且鼠伤寒沙门氏菌的毒力仍然对DsbA抑制剂敏感。我们的工作表明，在体外病理生理条件下，DsbA抑制剂可以同时具有抗毒力和抗生素作用。重要的是，我们发现DsbA抑制剂似乎在进化上具有稳健性，这为它们作为针对革兰氏阴性病原体的下一代抗菌剂的进一步开发提供了希望。
