N-hexanoyl-L-Homoserine lactone

N-hexanoyl-L-Homoserine lactone is a short-chain N-acyl homoserine lactone (AHL) which plays important roles in cell–cell communication system among microorganisms. N-hexanoyl-L-Homoserine lactone consists of a homoserine lactone ring linked via an amide bond to a six-carbon saturated acyl chain (hexanoyl). At neutral pH and room temperature, N-hexanoyl-L-Homoserine lactone is a water-soluble and lipophilic signal that diffuses freely across bacterial membranes, allowing rapid population-wide signal distribution^[1][2].

In vitro, different amounts of N-hexanoyl-L-Homoserine lactone (0.001µg/ml, 1µg/ml, and 100µg/ml) were added to the culture medium of Escherichia coli and then incubated at 35 ± 2ºC for 16 to 20h in an ambient air incubator. With increasing of N-hexanoyl-L-Homoserine lactone concentration, an increase in dry cell weight (2.45mg/ml to 4.63mg/ml) and insulin like growth factor 1(IGF-I) expression level (0.4mg/ml to 0.77mg/ml) was observed. N-hexanoyl-L-Homoserine lactone can be considered as protein production inducer in bacterial expression systems through the quorum sensing pathways^[3]. The experimental strain LB-001 was cultured in LB medium under conditions of 30℃, 10℃, and 10℃ with 2μM N-hexanoyl-L-Homoserine lactone added every 24h for up to 96h. N-hexanoyl-L-Homoserine lactone enhances the cold resistance of strain LB-001 by upregulating energy metabolism, antioxidation, and fatty acid synthesis genes, increasing ATP, superoxide dismutase (SOD), and reducing reactive oxygen species (ROS) levels under low-temperature stress^[3]. Winter-wheat seeds were primed in a 100ng/mL solution of N-hexanoyl-L-Homoserine lactone for 3h before the germination and seedling development were tested. Priming had a significant positive effect on germination with levels 1.2-fold greater than the untreated controls and increased coleoptile and radicle lengths 1.4-fold within two days. N-hexanoyl-L-Homoserine lactone may be a viable phyto-stimulator when applied as a seed primer^[4].

References:
[1] Stock F, Bilcke G, Decker S D, et al. Distinctive Growth and Transcriptional Changes of the Diatom Seminavis robusta in Response to Quorum Sensing Related Compounds. Front Microbiol. 2020 Jun 9:11:1240.
[2] Zhang, Y., Liu, F., Li, J.,et al. Specific quorum sensing signal molecules inducing the social behaviors of microbial populations in anaerobic digestion. Bioresource Technology. 2019 Feb; 273, 185–195.
[3] Babaeipour V, Vahidi H, Alikhani S, et al. Effect of Acyl Homoserine Lactone on Recombinant Production of Human Insulin-like Growth Factor-1 in Batch Culture of Escherichia coli. Protein Pept Lett. 2018;25(11):980-985.
[4] Wang Y B, Gu J M, Zhang F L,et al. Multi-omics analysis reveals the mechanisms by which C6-HSL enhances the resistance of typical functional bacteria in activated sludge to low-temperature stress. Sci Total Environ. 2024 Dec 1:954:176454.
[5] Moshynets O V, Babenko L M, Rogalsky S P, et al. Priming winter wheat seeds with the bacterial quorum sensing signal N-hexanoyl-L-Homoserine lactone (C6-HSL) shows potential to improve plant growth and seed yield. PLoS One. 2019 Feb 25;14(2):e0209460.

N-hexanoyl-L-Homoserine lactone是一种短链N-酰基高丝氨酸内酯(AHL)，在微生物细胞间通讯系统中扮演着重要角色。N-hexanoyl-L-Homoserine lactone由一个高丝氨酸内酯环通过酰胺键连接一条六碳饱和酰基链(己酰基)构成。在中性pH和室温下，N-hexanoyl-L-Homoserine lactone是水溶且亲脂的信号分子，可自由扩散穿过细菌膜，实现快速的群体信号传播^[1][2]。

体外实验中，将不同浓度的N-hexanoyl-L-Homoserine lactone（0.001µg/ml、1µg/ml和100µg/ml）加入大肠杆菌培养基，于35±2ºC环境空气培养箱中孵育16–20h。随着N-hexanoyl-L-Homoserine lactone浓度升高，细胞净重由2.45mg/ml增至4.63mg/ml，类胰岛素生长因子1（IGF-I）表达水平由0.4mg/ml升至0.77mg/ml。因此，N-hexanoyl-L-Homoserine lactone可通过群体感应途径作为细菌表达系统中的蛋白产量诱导剂^[3]。菌株LB-001在30℃、10℃和10℃条件下于LB培养基中培养，每24h添加2μM的N-hexanoyl-L-Homoserine lactone，持续96h。N-hexanoyl-L-Homoserine lactone通过上调能量代谢、抗氧化和脂肪酸合成基因，提高ATP和超氧化物歧化酶(SOD)水平，降低低温胁迫下的活性氧(ROS)水平，从而增强LB-001的耐寒性^[3]。冬小麦种子在100ng/mL的N-hexanoyl-L-Homoserine lactone溶液中浸种3h后进行发芽和幼苗测试。与未处理对照相比，浸种使发芽率提高1.2倍，两天内胚芽鞘和胚根长度增加1.4倍。N-hexanoyl-L-Homoserine lactone作为种子引发剂具有成为可行植物刺激剂的潜力^[4]。