Petrova Mariya I, Macklaim Jean M, Wuyts Sander, Verhoeven Tine, Vanderleyden Jos, Gloor Gregory B, Lebeer Sarah, Reid Gregor
Centre of Microbial and Plant Genetics, KU Leuven, Leuven, Belgium.
Department of Bioscience Engineering, University of Antwerp, Antwerp, Belgium.
Front Microbiol. 2018 Jun 15;9:1278. doi: 10.3389/fmicb.2018.01278. eCollection 2018.
represents a versatile bacterial genus, which can adapt to a wide variety of ecological niches, including human body sites such as the intestinal and urogenital tract. In this study, the complete genome sequence of the vaginal probiotic GR-1 was determined and compared to other strains at genomic and phenotypic level. The strain GR-1 was originally isolated from a female urethra, and was assessed with GG from a feces sample of a healthy male, and LC705 from a dairy product. A key difference is the absence in GR-1 and LC705 of the locus required for pili-mediated intestinal epithelial adhesion. In addition, the GR-1 genome contains a unique cluster for exopolysaccharide production, which is postulated to synthesize glucose-rich, rhamnose-lacking exopolysaccharide molecules that are different from the galactose-rich extracellular polysaccharide of GG. Compared to GG, GR-1 was also genetically predicted and experimentally shown to better metabolize lactose and maltose, and to better withstand oxidative stress, which is of relevance in the vagina. This study could thus provide a molecular framework for the selection of the optimal probiotic strain for each targeted niche and condition, but further substantiation of niche adaptation mechanisms of lactobacilli is warranted.
代表了一个多功能的细菌属，它能够适应各种各样的生态位，包括人体部位，如肠道和泌尿生殖道。在本研究中，测定了阴道益生菌GR-1的完整基因组序列，并在基因组和表型水平上与其他菌株进行了比较。GR-1菌株最初从一名女性尿道中分离出来，并与从一名健康男性粪便样本中分离出的GG以及从一种乳制品中分离出的LC705进行了评估。一个关键差异是GR-1和LC705中缺乏菌毛介导的肠道上皮粘附所需的位点。此外，GR-1基因组包含一个独特的胞外多糖产生簇，据推测该簇可合成富含葡萄糖、缺乏鼠李糖的胞外多糖分子，这些分子与GG富含半乳糖的胞外多糖不同。与GG相比，GR-1在基因预测和实验中还显示出能更好地代谢乳糖和麦芽糖，并能更好地抵御氧化应激，这在阴道环境中具有重要意义。因此，本研究可为针对每个目标生态位和条件选择最佳益生菌菌株提供分子框架，但乳杆菌生态位适应机制仍需进一步证实。
