Department of Molecular Biology and Genetics, Faculty of Arts and Sciences, Kilis 7 Aralık University, Kilis, Turkey.
Department of Food Engineering, Faculty of Engineering, Süleyman Demirel University, Isparta, Turkey.
Arch Microbiol. 2021 Jan;203(1):183-191. doi: 10.1007/s00203-020-02017-4. Epub 2020 Aug 16.
In this study, the presence of plasmids responsible for carbohydrate fermentation and antibiotic resistance and the stability of these plasmids in artificial gastric juice were investigated in 20 Lactobacillus plantarum strains with probiotic properties. Plasmid curing was performed with novobiocin, acriflavine and elevated incubation temperature to identify plasmids encoded with carbohydrate fermentation and antibiotic resistance genes and to compare them with artificial gastric juice. Plasmid profiling of the strains revealed that 100% of the strains were harbouring plasmids in varying sizes and numbers. The plasmid number of the potential probiotic strains ranged between 1 and 4, and the plasmid size ranged between 5.779 and 16.138 kb. The potential probiotic strains could not survive in the artificial gastric juice at pH 2.0. Although the strains maintained their viability in an artificial gastric juice at pH 2.5 and 3.0, and their derivatives lost their plasmids at a high rate (100%). Similarly, high levels of cured derivatives were obtained with 8 µg/mL novobiocin and 100 µg/mL acriflavine applications, and 24 h incubation at 43 °C. All the experiments were also performed to compare with two L. plantarum-type strains containing plasmids responsible for tetracycline and tetracycline + erythromycin resistances. Artificial gastric juice and other plasmid curing treatments caused a high-frequency loss in the antibiotic resistances of type strains. Determining plasmid stability in artificial gastric juice is a novel approach. Plasmid stability in the gastrointestinal tract is important for maintaining the plasmid-encoded probiotic properties.
在这项研究中，研究了 20 株具有益生菌特性的植物乳杆菌中与碳水化合物发酵和抗生素耐药性相关的质粒的存在及其在人工胃液中的稳定性。使用新生霉素、吖啶黄素和升高的孵育温度进行质粒消除，以鉴定编码碳水化合物发酵和抗生素耐药性基因的质粒，并将其与人工胃液进行比较。对菌株的质粒谱分析表明，所有菌株都携带不同大小和数量的质粒。潜在益生菌菌株的质粒数量在 1 到 4 之间，质粒大小在 5.779 到 16.138 kb 之间。潜在益生菌菌株在 pH 2.0 的人工胃液中无法存活。尽管这些菌株在 pH 2.5 和 3.0 的人工胃液中保持存活，但它们的衍生物以很高的速度（100%）失去质粒。同样，在 8 µg/mL 新生霉素和 100 µg/mL 吖啶黄素应用以及 43°C 孵育 24 小时的情况下，也获得了高比例的治愈衍生物。所有实验还与含有负责四环素和四环素+红霉素耐药性的质粒的两种植物乳杆菌型菌株进行了比较。人工胃液和其他质粒消除处理导致型菌株的抗生素耐药性高频丧失。确定人工胃液中的质粒稳定性是一种新方法。质粒在胃肠道中的稳定性对于维持质粒编码的益生菌特性很重要。
