Synthesis and antibiotic activity of novel acylated phloroglucinol compounds against methicillin-resistant Staphylococcus aureus
作者:Navriti Mittal、Haben H. Tesfu、Andrew M. Hogan、Silvia T. Cardona、John L. Sorensen
DOI:10.1038/s41429-019-0153-4
日期:2019.5
The rise in antibiotic resistance among pathogenic microorganisms has created an imbalance in the drugs available for treatment, in part due to the slow development of new antibiotics. Cystic fibrosis (CF) patients are highly susceptible to antibiotic-resistant pathogens, including methicillin-resistant Staphylococcus aureus (MRSA). Phloroglucinols and related polyketide natural products have demonstrated antimicrobial activity against a number of Gram-positive bacteria including S. aureus. In this study, we investigated a series of acylated phloroglucinol derivatives to determine their potential as lead compounds for the design of novel therapeutics. To assess the activity of these compounds, we determined the minimum inhibitory and bactericidal concentration (MIC and MBC, respectively), the minimum biofilm inhibitory and biofilm eradication concentration (MBIC and MBEC, respectively), and evaluated hemolytic activity, as well as their interaction with clinically relevant antibiotics. Of the 12 compounds tested against MRSA and methicillin-susceptible strains, four showed MIC values ranging from 0.125 to 8âµgâmlâ1 and all of them were bactericidal. However, none of the compounds were able to eradicate biofilms at the concentrations tested. Three of the four did not display hemolytic activity under the conditions tested. Further studies on the interactions of these compounds with clinically relevant antibiotics showed that phlorodipropanophenone displayed synergistic activity when paired with doxycycline. Our results suggest that these acylated phloroglucinols have potential for being further investigated as antibacterial leads.
病原微生物中抗生素抗性的上升造成了治疗用药物的不平衡,这在一定程度上是由于新抗生素的研发缓慢。囊性纤维化(CF)患者极易感染抗生素抗性病原体,包括耐甲氧西林金黄色葡萄球菌(MRSA)。间苯三酚类及其相关多酮天然产物已显示出对多种革兰氏阳性细菌(包括金黄色葡萄球菌)的抗菌活性。在本研究中,我们调查了一系列酰化间苯三酚衍生物质,以确定它们作为新型治疗药物设计的先导化合物的潜力。为了评估这些化合物的活性,我们测定了最低抑制浓度和杀菌浓度(MIC和MBC)、最低生物膜抑制浓度和生物膜消除浓度(MBIC和MBEC),并评估了溶血活性,以及它们与临床相关抗生素的相互作用。在针对MRSA和甲氧西林敏感菌株测试的12种化合物中,有4种的MIC值在0.125至8 µg/ml之间,且均为杀菌性。然而,在测试的浓度下,这些化合物均无法消除生物膜。其中3种在测试条件下未显示溶血活性。进一步研究这些化合物与临床相关抗生素的相互作用,结果显示,苯二丙酸苯酮在配伍强力霉素时表现出协同活性。我们的结果表明,这些酰化间苯三酚具有作为抗菌先导物进一步研究的潜力。