sortase A与变异链球菌致龋性关系的代谢组学研究

Link between sortase A function and cariogenicity of Streptococcus mutans: a preliminary metabolomics analysis

目的探索srt A基因编码的转肽酶sortase A(Srt A)影响变异链球菌致龋性的机制。方法采用基于1H核磁共振波谱(NMR)的代谢组学方法,比较野生型变异链球菌UA159与srt A基因缺陷型变异链球菌UA159的胞外代谢产物;联合使用主成分分析和正交偏最小二乘法—判别分析鉴定不同菌株之间代谢产物的差异。结果大多数有差异性的代谢产物是未知的,可识别的差异性代谢产物有亮氨酸和缬氨酸(δ0.92×10-6~1.20×10-6)、乳酸(δ1.28×10-6)、酮戊二酸(δ3.00×10-6)、甘氨酸(δ3.60×10-6)。结论在进一步完善微生物代谢产物数据库的基础上,1H NMR代谢组学可用于龋病病因的研究。

Objective This study intends to explore the mechanism underlying the support of sortase A（Srt A） of the cariogenicity of Streptococcus mutans（S. mutans）. Methods We performed a metabonomics study based on 1 H nuclear magnetic resonance spectroscopy（NMR）, in which we compared the extracellular metabolites of wild-type S. mutans UA159 with those of its Srt A-deficient strain. Metabolite differences among strains were identified using a combination of principal component analysis and orthogonality partial least square discriminant analysis. Results Several differences corresponding mostly to unknown metabolites were identified. Some amino acids such as leucine and valine（δ 0.92×10-6-1.20×10-6）, lactic acid（δ1.28×10-6）, oxoglutaric acid（δ 3.00×10-6）, and glycine（δ 3.60×10-6） differed among strains. Conclusion This work establishes the feasibility of using 1 H NMR-based metabonomics to provide leads for research into molecular factors that promote caries. The database of microbial metabolites should be also improved in further studies.