The Bifidobacterium dentium Bd1 genome sequence reflects its genetic adaptation to the human oral cavity.
The Bifidobacterium dentium Bd1 genome sequence reflects its genetic adaptation to the human oral cavity.
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DOI：
10.1371/journal.pgen.1000785
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发表时间：
2009-12
期刊：
影响因子：
4.5
通讯作者：
van Sinderen D
中科院分区：
文献类型：
--
作者：
Ventura M;Turroni F;Zomer A;Foroni E;Giubellini V;Bottacini F;Canchaya C;Claesson MJ;He F;Mantzourani M;Mulas L;Ferrarini A;Gao B;Delledonne M;Henrissat B;Coutinho P;Oggioni M;Gupta RS;Zhang Z;Beighton D;Fitzgerald GF;O'Toole PW;van Sinderen D
益生菌是人体肠道微生物群中相对占优势的成分之一，被认为是肠道有益细菌（益生菌）的关键类群之一。然而，除了促进健康的分类群之外，双歧杆菌属还包括牙双歧杆菌（Bifidobacterium dentium），一种机会性致龋病原体。B.牙本质在口腔中存活并促进龋齿发展的机制尚不清楚。B的基因组。对从龋齿中分离的菌株Dentium Bd 1进行测序，以揭示具有2，143个预测开放阅读框的单个环状2，636，368碱基对染色体。基因组序列的注释揭示了B.牙质通过专门的营养获取、抗微生物剂的防御以及增加口腔生态位内的适应性和竞争力的基因产物来适应口腔环境。B。Dentium Bd 1被证明代谢各种各样的碳水化合物，与基于基因组的预测一致，同时还确定了与组织粘附、耐酸性和人类唾液衍生化合物代谢有关的定殖和持久性因素。全局转录组分析表明，许多编码这些预测性状的基因在相关生理条件下高度表达。这是第一份报告，通过各种基因组方法，确定特定的遗传适应的双歧杆菌分类群，齿双歧杆菌Bd 1，生活方式作为口腔中的致龋微生物。计算机模拟分析和比较基因组杂交实验清楚地揭示了各种B之间的高水平的基因组保守性。牙本质菌株这些数据表明，这种机会性致龋原的基因组已经通过非常有限数量的水平基因获取事件进化，突出了将细菌与机会性病原体分开的狭窄边界。完整细菌基因组序列的可获得性通过显著增强我们对细菌的生理学、遗传学和进化发展的理解而为微生物学领域提供了重要变化。双歧杆菌是这样的微生物之一，由于它们在维持平衡的胃肠道（GIT）微生物区系中的感知作用，它们是具有生物技术意义的哺乳动物微生物。因此，双歧杆菌经常被用作功能性食品中的健康促进或益生菌组分，并且代表了越来越多的科学兴趣领域。然而，在双歧杆菌属内，并非所有物种都对宿主的健康提供有益的影响。事实上，牙双歧杆菌被认为是一种机会致病菌，因为它与龋齿的发生有关。在这份手稿中，我们描述了完整的遗传组成的B。Dentium Bd 1基因组，并讨论了解释这种微生物如何适应人类口腔并赋予致龋表型的功能。此外，我们对B进行了比较基因组分析。为了追踪机会性口腔病原体B之间的遗传差异/相似性，Dentium Bd 1和密切相关的肠道双歧杆菌。
Bifidobacteria, one of the relatively dominant components of the human intestinal microbiota, are considered one of the key groups of beneficial intestinal bacteria (probiotic bacteria). However, in addition to health-promoting taxa, the genus Bifidobacterium also includes Bifidobacterium dentium, an opportunistic cariogenic pathogen. The genetic basis for the ability of B. dentium to survive in the oral cavity and contribute to caries development is not understood. The genome of B. dentium Bd1, a strain isolated from dental caries, was sequenced to completion to uncover a single circular 2,636,368 base pair chromosome with 2,143 predicted open reading frames. Annotation of the genome sequence revealed multiple ways in which B. dentium has adapted to the oral environment through specialized nutrient acquisition, defences against antimicrobials, and gene products that increase fitness and competitiveness within the oral niche. B. dentium Bd1 was shown to metabolize a wide variety of carbohydrates, consistent with genome-based predictions, while colonization and persistence factors implicated in tissue adhesion, acid tolerance, and the metabolism of human saliva-derived compounds were also identified. Global transcriptome analysis demonstrated that many of the genes encoding these predicted traits are highly expressed under relevant physiological conditions. This is the first report to identify, through various genomic approaches, specific genetic adaptations of a Bifidobacterium taxon, Bifidobacterium dentium Bd1, to a lifestyle as a cariogenic microorganism in the oral cavity. In silico analysis and comparative genomic hybridization experiments clearly reveal a high level of genome conservation among various B. dentium strains. The data indicate that the genome of this opportunistic cariogen has evolved through a very limited number of horizontal gene acquisition events, highlighting the narrow boundaries that separate commensals from opportunistic pathogens. The accessibility of complete bacterial genome sequences has provided important changes to the field of microbiology by significantly enhancing our understanding of the physiology, genetics, and evolutionary development of bacteria. Bifidobacteria are among such microorganisms, being mammalian commensals of biotechnological significance due to their perceived role in maintaining a balanced gastrointestinal (GIT) microflora. Bifidobacteria are therefore often applied as health-promoting or probiotic components in functional food products and represent a growing area of scientific interest. However, within the genus Bifidobacterium not all species provide beneficial effects on the host's health. In fact, the Bifidobacterium dentium species is considered an opportunistic pathogen since it has been associated with the development of dental caries. In this manuscript, we describe the complete genetic make-up of the B. dentium Bd1 genome and discuss functions that explain how this microorganism has adapted to the oral human cavity and imparts a cariogeneous phenotype. Moreover, we performed comparative genomic analyses of B. dentium genome with other bifidobacterial genomes in order to trace genetic differences/similarities between the opportunistic oral pathogen B. dentium Bd1 and closely related intestinal bifidobacteria.
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影响因子：
3
作者：
Chan CX;Beiko RG;Ragan MA
通讯作者：
Ragan MA
DOI：
10.1073/pnas.0511017103
发表时间：
2006-02-21
影响因子：
11.1
作者：
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通讯作者：
Henriques-Normark, B
影响因子：
3.2
作者：
BLACK, PN
通讯作者：
BLACK, PN
DOI：
10.1073/pnas.0606924103
发表时间：
2006-10-17
影响因子：
11.1
作者：
Chain, Patrick S. G.;Denef, Vincent J.;Tiedje, James M.
通讯作者：
Tiedje, James M.
影响因子：
64.8
作者：
Alm, RA;Ling, LSL;Trost, TJ
通讯作者：
Trost, TJ