College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an 710119, China.
College of Food Engineering and Nutritional Science, Shaanxi Normal University, Xi'an 710119, China.
J Dairy Sci. 2020 Jan;103(1):117-127. doi: 10.3168/jds.2019-17049. Epub 2019 Nov 6.
Trait stability of Lactobacillus plantarum was studied following daily subculture over a 90-d period. Acid and bile tolerance, self-aggregation ability, cell hydrophobicity, pathogen inhibition activity, and cholesterol removal ability of cultures subcultured 30 (Lp30), 60 (Lp60), or 90 (Lp90) times were not significantly different from the original strain (Lp0). However, carbohydrate metabolism patterns did change; the Lp0 culture was unable to use d-sorbitol, α-methyl-d-mannose, and d-raffinose, whereas Lp30, Lp60, and Lp90 cultures could. Furthermore, gluconate and gentiobiose were fully used by the Lp0 culture but only poorly used by the Lp30, Lp60, and Lp90 cultures. Milk fermentation test confirmed that L. plantarum was unable to use lactose throughout laboratory evolution. Six non-synonymous mutations in genome of the Lp30, Lp60, and Lp90 cultures were identified by whole-genome sequencing, including mutant gene encoding the phosphoglycerate mutase, which is closely related to the transport and metabolism of carbohydrates. These mutations may play an important role in changes of carbohydrate metabolism patterns observed. Understanding the evolutionary characteristics of L. plantarum will help in development for food industry.
研究了植物乳杆菌在 90 天的每日传代培养后其特性的稳定性。培养物的耐酸和耐胆汁能力、自聚集能力、细胞疏水性、抑制病原体活性和胆固醇去除能力，经过 30 次（Lp30）、60 次（Lp60）或 90 次（Lp90）传代培养后与原始菌株（Lp0）相比没有显著差异。然而，碳水化合物代谢模式确实发生了变化；Lp0 培养物不能使用 d-山梨醇、α-甲基-d-甘露糖和 d-棉子糖，而 Lp30、Lp60 和 Lp90 培养物可以。此外，葡萄糖酸盐和龙胆二糖完全被 Lp0 培养物利用，但仅被 Lp30、Lp60 和 Lp90 培养物部分利用。牛奶发酵试验证实，植物乳杆菌在整个实验室进化过程中不能利用乳糖。通过全基因组测序鉴定了 Lp30、Lp60 和 Lp90 培养物基因组中的 6 个非同义突变，包括突变基因编码磷酸甘油酸变位酶，该酶与碳水化合物的运输和代谢密切相关。这些突变可能在观察到的碳水化合物代谢模式变化中起重要作用。了解植物乳杆菌的进化特征将有助于食品工业的发展。
