Department of Microbiology & Immunology, School of Medicine, Virginia Commonwealth University, Richmond, Virginia, USA.
Center for Microbiome Engineering and Data Analysis, Virginia Commonwealth University, Richmond, Virginia, USA.
Mol Oral Microbiol. 2024 Dec;39(6):461-467. doi: 10.1111/omi.12478. Epub 2024 Jul 25.
Porphyromonas gingivalis is a keystone pathogen in periodontitis, and Streptococcus sanguinis is an abundant oral commensal bacterium associated with periodontal health. However, the interaction between P. gingivalis and S. sanguinis remains obscure. Here, we established a strategy for high-throughput measurement of the cell number of P. gingivalis in the coculture with S. sanguinis by detecting the concentration of hydrogen sulfate. The interaction between P. gingivalis and over 2000 S. sanguinis single-gene mutants was characterized using this strategy, and several interaction-associated genes in S. sanguinis were determined by detecting more P. gingivalis cells in the coculture with matched S. sanguinis mutants. Three S. sanguinis interaction-associated genes were predicted to be responsible for cysteine metabolism, and the supplementation of exogenous L-cysteine promoted the cell number of P. gingivalis in the coculture with S. sanguinis. Thus, exogenous L-cysteine and the compromised cysteine metabolism in S. sanguinis enhanced the growth of P. gingivalis in the existence of S. sanguinis. Additionally, the interaction between P. gingivalis and other Streptococcus spp. was examined, and S. pneumoniae was the only streptococci that had no inhibition on the cell number of P. gingivalis. In total, this study established a new strategy for high-throughput screening of the interaction between Streptococcus and P. gingivalis and discovered a set of genes in S. sanguinis that impacted the interaction. The influence of exogenous L-cysteine on the interaction between P. gingivalis and S. sanguinis in the oral cavity needs further investigation.
牙龈卟啉单胞菌是牙周炎的关键病原体，而唾液链球菌是一种与牙周健康相关的丰富口腔共生菌。然而，牙龈卟啉单胞菌和唾液链球菌之间的相互作用仍然不清楚。在这里，我们通过检测硫酸氢盐的浓度，建立了一种高通量测量牙龈卟啉单胞菌在与唾液链球菌共培养中的细胞数的策略。我们利用该策略研究了牙龈卟啉单胞菌与超过 2000 个唾液链球菌单基因突变体之间的相互作用，并通过在与匹配的唾液链球菌突变体的共培养中检测到更多的牙龈卟啉单胞菌细胞，确定了几个与相互作用相关的唾液链球菌基因。预测三个与唾液链球菌相互作用相关的基因负责半胱氨酸代谢，并且在与唾液链球菌的共培养中外源 L-半胱氨酸的补充促进了牙龈卟啉单胞菌的细胞数增加。因此，外源 L-半胱氨酸和唾液链球菌中受损的半胱氨酸代谢增强了在存在唾液链球菌的情况下牙龈卟啉单胞菌的生长。此外，还检查了牙龈卟啉单胞菌与其他链球菌之间的相互作用，只有肺炎链球菌没有抑制牙龈卟啉单胞菌的细胞数。总的来说，这项研究建立了一种高通量筛选链球菌和牙龈卟啉单胞菌相互作用的新策略，并发现了一组影响相互作用的唾液链球菌基因。需要进一步研究外源性 L-半胱氨酸对口腔中牙龈卟啉单胞菌和唾液链球菌相互作用的影响。
