Felix LewisOscar, Mylonakis Eleftherios, Fuchs Beth Burgwyn
Division of Infectious Diseases, Rhode Island Hospital, Alpert Medical School and Brown University, Providence, RI, United States.
Front Microbiol. 2021 Apr 16;12:663481. doi: 10.3389/fmicb.2021.663481. eCollection 2021.
There is a drought of new antibacterial compounds that exploit novel targets. Thioredoxin reductase (TrxR) from the Gram-positive bacterial antioxidant thioredoxin system has emerged from multiple screening efforts as a potential target for auranofin, ebselen, shikonin, and allicin. Auranofin serves as the most encouraging proof of concept drug, demonstrating TrxR inhibition can result in bactericidal effects and inhibit Gram-positive bacteria in both planktonic and biofilm states. Minimal inhibitory concentrations are on par or lower than gold standard medications, even among drug resistant isolates. Importantly, existing drug resistance mechanisms that challenge treatment of infections like do not confer resistance to TrxR targeting compounds. The observed inhibition by multiple compounds and inability to generate a bacterial genetic mutant demonstrate TrxR appears to play an essential role in Gram-positive bacteria. These findings suggest TrxR can be exploited further for drug development. Examining the interaction between TrxR and these proof of concept compounds illustrates that compounds representing a new antimicrobial class can be developed to directly interact and inhibit the validated target.
新型抗菌化合物的研发面临着靶点新颖性不足的问题。革兰氏阳性菌抗氧化硫氧还蛋白系统中的硫氧还蛋白还原酶(TrxR)在多次筛选中脱颖而出,成为金诺芬、依布硒啉、紫草素和大蒜素的潜在作用靶点。金诺芬是最具前景的概念验证药物,它证明了TrxR抑制可产生杀菌作用,并能抑制革兰氏阳性菌的浮游态和生物膜态。即使在耐药菌株中,其最低抑菌浓度也与金标准药物相当或更低。重要的是,现有的挑战感染治疗的耐药机制并不会使细菌对靶向TrxR的化合物产生耐药性。多种化合物对TrxR的抑制作用以及无法产生细菌遗传突变体表明,TrxR在革兰氏阳性菌中似乎起着至关重要的作用。这些发现表明,TrxR可进一步用于药物研发。研究TrxR与这些概念验证化合物之间的相互作用表明,可以开发出代表新型抗菌类别的化合物,使其直接与经过验证的靶点相互作用并抑制该靶点。