Pattinson Adam, Bahia Sandeep, Le Gall Gwénaëlle, Morris Christopher J, Harding Sarah V, McArthur Michael
Norwich Medical School, Bob Champion Building for Research and Education, University of East Anglia, Norwich, United Kingdom.
School of Pharmacy, University of East Anglia, Norwich, United Kingdom.
Front Microbiol. 2023 May 12;13:1092230. doi: 10.3389/fmicb.2022.1092230. eCollection 2022.
is the causative agent of the tropical disease, melioidosis. It is intrinsically resistant to many antimicrobials and treatment requires an onerous regimen of intravenous and orally administered drugs. Relapse of disease and high rates of mortality following treatment are common, demonstrating the need for new anti- agents. The cationic bola-amphiphile, 12,12'-(dodecane-1,12-diyl) bis (9-amino-1,2,3,4-tetrahydroacridinium), referred to as 12-bis-THA, is a molecule with the potential to treat infections. 12-bis-THA spontaneously forms cationic nanoparticles that bind anionic phospholipids in the prokaryotic membrane and are readily internalized. In this study, we examine the antimicrobial activity of 12-bis-THA against strains of . As produces a polysaccharide capsule we first examined if this extra barrier influenced the activity of 12-bis-THA which is known to act on the bacterial envelope. Therefore two strains of were selected for further testing, strain E264 which does not produce a capsule and strain E555 which does produce a capsule that is chemically similar to that found in . In this study no difference in the minimum inhibitory concentration (MIC) was observed when capsulated (E555) and unencapsulated (E264) strains of were compared, however time-kill analysis showed that the unencapsulated strain was more susceptible to 12-bis-THA. The presence of the capsule did not affect the membrane permeation of 12-bis-THA at MIC concentrations. Proteomic and metabolomic analyses showed that 12-bis-THA causes a shift in central metabolism away from glycolysis and glyoxylate cycle, and suppressed the production of the F domain of ATP synthase. In summary, we provide insight into the molecular mechanisms underpinning the activity of 12-bis-THA against and discuss its potential for further development.
是热带疾病类鼻疽的病原体。它对许多抗菌药物具有内在抗性,治疗需要采用繁琐的静脉注射和口服药物方案。疾病复发和治疗后高死亡率很常见,这表明需要新的抗菌剂。阳离子双尾两亲分子12,12'-(十二烷-1,12-二基)双(9-氨基-1,2,3,4-四氢吖啶鎓),简称为12-双-THA,是一种有潜力治疗感染的分子。12-双-THA能自发形成阳离子纳米颗粒,这些颗粒可结合原核细胞膜中的阴离子磷脂并易于内化。在本研究中,我们检测了12-双-THA对菌株的抗菌活性。由于会产生多糖荚膜,我们首先研究了这个额外的屏障是否会影响已知作用于细菌包膜的12-双-THA的活性。因此选择了两株进行进一步测试,不产生荚膜的E264菌株和产生与中发现的化学性质相似的荚膜的E555菌株。在本研究中,当比较有荚膜(E555)和无荚膜(E264)的菌株时,未观察到最小抑菌浓度(MIC)有差异,然而时间-杀菌分析表明无荚膜菌株对12-双-THA更敏感。在MIC浓度下,荚膜的存在不影响12-双-THA的膜渗透。蛋白质组学和代谢组学分析表明,12-双-THA导致中心代谢从糖酵解和乙醛酸循环发生转变,并抑制了ATP合酶F结构域的产生。总之,我们深入了解了12-双-THA对的活性所基于的分子机制,并讨论了其进一步开发的潜力。