Bacillus subtilis is a Gram-positive probiotic bacterium that successfully colonises plant roots due to its ability to utilise various sugars. The vast probiotic potential of B. subtilis has been recently demonstrated in numerous host organisms under different environmental conditions. We examined the probiotic potential of B. subtilis against the pathogenic bacterium Streptococcus mutans, which is involved in various oral disorders due to its robust biofilm-forming capability. B. subtilis cells attenuated biofilm formation by S. mutans during their dual growth in the presence of sugar alcohols. Transcription of genes encoding key enzymes in the metabolism of sugar alcohols by B. subtilis were highly induced. Moreover, growth-curve analysis suggested that B. subtilis is more efficient at early utilising sugar alcohols than S. mutans, as supported by the bacterial metabolic activity rates. Similarly, a comparison of secondary metabolites of mono and mixed cultures of B. subtilis and S. mutans indicated that B. subtilis is more active metabolically in the dual culture. Finally, knock-out mutations of the genes encoding key enzymes in the central metabolic pathway significantly reduced B. subtilis' ability to mitigate biofilm formation by S. mutans. We conclude that effective metabolism of sugar alcohols by B. subtilis reinforces the probiotic potential of this bacterium against pathogenic species such as S. mutans.

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枯草芽孢杆菌糖醇代谢的效率控制其对致龋变形链球菌的益生菌作用。

枯草芽孢杆菌是一种革兰氏阳性益生菌，由于其能够利用各种糖类而成功地定植于植物根部。最近在不同环境条件下的众多宿主生物中证明了枯草芽孢杆菌的巨大益生菌潜力。我们检查了枯草芽孢杆菌对致病菌变形链球菌的益生菌潜力，由于其强大的生物膜形成能力，该菌与各种口腔疾病有关。B. subtilis 细胞在糖醇存在下的双重生长过程中减弱了 S. mutans 的生物膜形成。枯草芽孢杆菌糖醇代谢关键酶基因的转录受到高度诱导。此外，生长曲线分析表明，枯草芽孢杆菌在早期利用糖醇方面比变形链球菌更有效，由细菌代谢活动率支持。同样，枯草芽孢杆菌和变形链球菌的单一和混合培养物的次生代谢物的比较表明，枯草芽孢杆菌在双重培养中的代谢更加活跃。最后，在中央代谢途径中编码关键酶的基因的敲除突变显着降低了枯草芽孢杆菌减轻变形链球菌生物膜形成的能力。我们得出结论，枯草芽孢杆菌对糖醇的有效代谢增强了这种细菌对致病物种（如变形链球菌）的益生菌潜力。在中央代谢途径中编码关键酶的基因的敲除突变显着降低了枯草芽孢杆菌减轻变形链球菌生物膜形成的能力。我们得出结论，枯草芽孢杆菌对糖醇的有效代谢增强了这种细菌对致病物种（如变形链球菌）的益生菌潜力。在中央代谢途径中编码关键酶的基因的敲除突变显着降低了枯草芽孢杆菌减轻变形链球菌生物膜形成的能力。我们得出结论，枯草芽孢杆菌对糖醇的有效代谢增强了这种细菌对致病物种（如变形链球菌）的益生菌潜力。