2-heptyl-3-hydroxy-4(1H)-quinolone, a quorum-sensing (QS) signal that regulates numerous virulence genes including those involved in iron scavenging[1]. 2-heptyl-3-hydroxy-4(1H)-Quinolone is useful for the development of microplate ELISA for the diagnosis of Pseudomonas aeruginosa infection[2].
In vitro, 2-heptyl-3-hydroxy-4(1H)-quinolone treatment for 24h significantly activated β-galactosidase activity in P. putida KT2440 cells, with an EC50 value of 0.15 ± 0.02μM[3]. Pseudomonas aeruginosa strains grown in Luria-Bertani broth (LB) in the presence of 60µM 2-heptyl-3-hydroxy-4(1H)-Quinolone at 37°C for 8h (200r.p.m.) showed significantly increased PA-IL lectin, pyocyanin, and elastase production[4]. Treatment of HT22 cells with 0.6μM of 2-heptyl-3-hydroxy-4(1H)-quinolone for 2 hours significantly inhibited cell death mediated by 5mM glutamate, restored the normal morphology of the cells, and enhanced cell viability[5].
In vivo, 2-heptyl-3-hydroxy-4(1H)-quinolone treatment via intraperitoneal injection of 10mg/kg/day for 10 days in mice with collagenous arthritis (CIA) resulted in a significant reduction in the proportion of FoxP3+ expressing CD4+ cells (Treg cells) in the inflamed paws and blood of the mice[6]. A single dose of 2-heptyl-3-hydroxy-4(1H)-quinolone (10mg/kg) intraperitoneal injection at 15min significantly inhibited inositol polyphosphate hydrolysis and cAMP formation in the brain tissue of adult mice[7].
References:
[1] Hodgkinson J T, Galloway W R J D, Welch M, et al. Microwave-assisted preparation of the quorum-sensing molecule 2-heptyl-3-hydroxy-4 (1 H)-quinolone and structurally related analogs[J]. nature protocols, 2012, 7(6): 1184-1192.
[2] Montagut E J, Raya J, Martin-Gomez M T, et al. An immunochemical approach to detect the quorum sensing-regulated virulence factor 2-heptyl-4-quinoline N-oxide (HQNO) produced by pseudomonas aeruginosa clinical isolates[J]. Microbiology spectrum, 2022, 10(4): e01073-21.
[3] Müller C, Fetzner S. A Pseudomonas putida bioreporter for the detection of enzymes active on 2-alkyl-4 (1 H)-quinolone signalling molecules[J]. Applied microbiology and biotechnology, 2013, 97(2): 751-760.
[4] Diggle S P, Winzer K, Chhabra S R, et al. The Pseudomonas aeruginosa quinolone signal molecule overcomes the cell density‐dependency of the quorum sensing hierarchy, regulates rhl‐dependent genes at the onset of stationary phase and can be produced in the absence of LasR[J]. Molecular microbiology, 2003, 50(1): 29-43.
[5] Selvaraj B, Kim D W, Park J S, et al. Neuroprotective effects of 2-heptyl-3-hydroxy-4-quinolone in HT22 mouse hippocampal neuronal cells[J]. Bioorganic & Medicinal Chemistry Letters, 2021, 49: 128312.
[6] Ogbechi J, Huang Y S, Clanchy F I L, et al. Modulation of immune cell function, IDO expression and kynurenine production by the quorum sensor 2-heptyl-3-hydroxy-4-quinolone (PQS)[J]. Frontiers in Immunology, 2022, 13: 1001956.
[7] Di Menna L, Busceti C L, Ginerete R P, et al. The bacterial quorum sensing molecule, 2-heptyl-3-hydroxy-4-quinolone (PQS), inhibits signal transduction mechanisms in brain tissue and is behaviorally active in mice[J]. Pharmacological Research, 2021, 170: 105691.
2-heptyl-3-hydroxy-4(1H)-quinolone是一种群体感应(QS)信号分子，可调控包括铁获取相关基因在内的多种毒力基因[1]。2-heptyl-3-hydroxy-4(1H)-quinolone可用于开发微孔板ELISA检测方法，用于铜绿假单胞菌感染的诊断[2]。
在体外，2-heptyl-3-hydroxy-4(1H)-quinolone处理24小时可显著激活P. putida KT2440细胞的β-半乳糖苷酶活性，EC50值为0.15±0.02μM[3]。在含60µM 的2-heptyl-3-hydroxy-4(1H)-quinolone的LB培养基中，在37℃、200r.p.m.条件下培养铜绿假单胞菌菌株8小时，PA-IL凝集素、绿脓菌素和弹性蛋白酶产量显著增加[4]。0.6μM浓度的2-heptyl-3-hydroxy-4(1H)-quinolone处理HT22细胞2小时，能显著抑制5mM谷氨酸介导的细胞死亡，恢复细胞正常形态并提高存活率[5]。
在体内，以10mg/kg/day剂量的2-heptyl-3-hydroxy-4(1H)-quinolone经腹腔注射10天，可显著降低胶原性关节炎(CIA)小鼠模型的炎症足爪和血液中FoxP3+CD4+细胞（Treg细胞）的比例[6]。单次腹腔注射10mg/kg剂量的2-heptyl-3-hydroxy-4(1H)-quinolone 15分钟后，能显著抑制成年小鼠脑组织中的肌醇多磷酸水解和cAMP形成[7]。