Department of Molecular Biology, Division of Biological Sciences, University of California at San Diego, La Jolla, California, USA.
Central European Institute of Technology, Masaryk University, Brno, Czechia.
Microb Physiol. 2022;32(1-2):30-44. doi: 10.1159/000518954. Epub 2021 Sep 23.
The human microbiome influences human health in both negative and positive ways. Studies on the transportomes of these organisms yield information that may be utilized for various purposes, including the identification of novel drug targets and the manufacture of improved probiotic strains. Moreover, these genomic analyses help to improve our understanding of the physiology and metabolic capabilities of these organisms. The present study is a continuation of our studies on the transport proteins of the major gut microbes. Bifidobacterium species are essential members of the human gut microbiome, and they initiate colonization of the gut at birth, providing health benefits that last a lifetime. In this study we analyze the transportomes of nine bifidobacterial species: B. adolescentis, B. animalis, B. bifidum, B. breve, B. catenulatum, B. dentium, B. longum subsp. infantis, B. longum subsp. longum, and B. pseudocatenulatum. All of these species have proven probiotic characteristics and exert beneficial effects on human health. Surprisingly, we found that all nine of these species have similar pore-forming toxins and drug exporters that may play roles in pathogenesis. These species have transporters for amino acids, carbohydrates, and proteins, essential for their organismal lifestyles and adaption to their respective ecological niches. The strictly probiotic species, B. bifidum, however, contains fewer such transporters, thus indicative of limited interactions with host cells and other gut microbial counterparts. The results of this study were compared with those of our previous studies on the transportomes of multiple species of Bacteroides, Escherichia coli/Salmonella, and Lactobacillus. Overall, bifidobacteria have larger transportomes (based on percentages of total proteins) than the previously examined groups of bacterial species, with a preference for primary active transport systems over secondary carriers. Taken together, these results provide useful information about the physiologies and pathogenic potentials of these probiotic organisms as reflected by their transportomes.
人体微生物组以负面和正面的方式影响人类健康。对这些生物体的转运体的研究提供了可能用于各种目的的信息，包括鉴定新的药物靶点和制造改良的益生菌株。此外，这些基因组分析有助于提高我们对这些生物体的生理学和代谢能力的理解。本研究是我们对主要肠道微生物的转运蛋白研究的延续。双歧杆菌属是人类肠道微生物组的重要成员，它们在出生时就开始定植肠道，提供终生的健康益处。在这项研究中，我们分析了 9 种双歧杆菌属物种的转运体：青春双歧杆菌、动物双歧杆菌、两歧双歧杆菌、短双歧杆菌、长双歧杆菌、齿双歧杆菌、婴儿双歧杆菌、长双歧杆菌和假长双歧杆菌。所有这些物种都具有已被证实的益生菌特性，并对人类健康产生有益影响。令人惊讶的是，我们发现所有这 9 个物种都具有相似的孔形成毒素和药物外排泵，这些可能在发病机制中发挥作用。这些物种具有氨基酸、碳水化合物和蛋白质的转运体，这对它们的生物生活方式和适应各自的生态位是必不可少的。然而，严格的益生菌物种双歧杆菌含有较少的此类转运体，这表明与宿主细胞和其他肠道微生物的相互作用有限。本研究的结果与我们之前对多种拟杆菌、大肠杆菌/沙门氏菌和乳杆菌的转运体的研究结果进行了比较。总的来说，双歧杆菌的转运体（基于总蛋白的百分比）比之前研究的细菌物种组更大，它们更喜欢主动运输系统而不是次级载体。总之，这些结果提供了关于这些益生菌生物体的生理学和发病潜力的有用信息，反映在它们的转运体中。
