Oliveira Letícia C, Saraiva Tessália D L, Silva Wanderson M, Pereira Ulisses P, Campos Bruno C, Benevides Leandro J, Rocha Flávia S, Figueiredo Henrique C P, Azevedo Vasco, Soares Siomar C
Laboratory of Cellular and Molecular Genetics, Institute of Biological Sciences, Federal University of Minas Gerais, Belo Horizonte-MG, Brazil.
Department of Preventive Veterinary Medicine, State University of Londrina, Londrina-PR, Brazil.
PLoS One. 2017 Apr 6;12(4):e0175116. doi: 10.1371/journal.pone.0175116. eCollection 2017.
Lactococcus lactis subsp. lactis NCDO 2118 was recently reported to alleviate colitis symptoms via its anti-inflammatory and immunomodulatory activities, which are exerted by exported proteins that are not produced by L. lactis subsp. lactis IL1403. Here, we used in vitro and in silico approaches to characterize the genomic structure, the safety aspects, and the immunomodulatory activity of this strain. Through comparative genomics, we identified genomic islands, phage regions, bile salt and acid stress resistance genes, bacteriocins, adhesion-related and antibiotic resistance genes, and genes encoding proteins that are putatively secreted, expressed in vitro and absent from IL1403. The high degree of similarity between all Lactococcus suggests that the Symbiotic Islands commonly shared by both NCDO 2118 and KF147 may be responsible for their close relationship and their adaptation to plants. The predicted bacteriocins may play an important role against the invasion of competing strains. The genes related to the acid and bile salt stresses may play important roles in gastrointestinal tract survival, whereas the adhesion proteins are important for persistence in the gut, culminating in the competitive exclusion of other bacteria. Finally, the five secreted and expressed proteins may be important targets for studies of new anti-inflammatory and immunomodulatory proteins. Altogether, the analyses performed here highlight the potential use of this strain as a target for the future development of probiotic foods.
乳酸乳球菌乳酸亚种NCDO 2118最近被报道可通过其抗炎和免疫调节活性缓解结肠炎症状，这些活性由乳酸乳球菌乳酸亚种IL1403不产生的分泌蛋白发挥。在此，我们使用体外和计算机方法来表征该菌株的基因组结构、安全性以及免疫调节活性。通过比较基因组学，我们鉴定了基因组岛、噬菌体区域、胆盐和酸应激抗性基因、细菌素、黏附相关和抗生素抗性基因，以及编码推测分泌、体外表达且IL1403中不存在的蛋白质的基因。所有乳球菌之间的高度相似性表明，NCDO 2118和KF147共同拥有的共生岛可能是它们密切关系及其对植物适应性的原因。预测的细菌素可能在抵御竞争菌株入侵方面发挥重要作用。与酸和胆盐应激相关的基因可能在胃肠道存活中发挥重要作用，而黏附蛋白对于在肠道中持续存在很重要，最终导致对其他细菌的竞争性排除。最后，这五种分泌和表达的蛋白质可能是新型抗炎和免疫调节蛋白研究的重要靶点。总之，此处进行的分析突出了该菌株作为未来益生菌食品开发靶点的潜在用途。
