血链球菌不同菌株产生对氨基苯甲酸的比较研究

A Comparative Study on the Capacities of Different Strains of Strepto coccus Sanguis for PAminobenzoic Acid Production

为对血链菌的不同菌株产生对氨基苯甲酸(PABA)的能力进行比较研 究，采用RP－HPLC技术测定血链 菌的4种不同菌株在蔗糖TPY液体培养基中培养后产生的PABA含量并进行比较。血链菌10556 、10557、S34、H7-4分别在蔗糖TPY液体培养基中培养，菌液经预处理后，进 样测定PABA含量。结果：血链菌10556、10557、S34、H7-4产生PABA的平均值 分别为1.979±0.081μg/ml、1.383±0.193μg/ml、1.983±0.052μg/ml、1.032±0229 μ g/ml，血链菌10556、S34产生PABA的量大于血链菌10557、H7-4，有显著性差异(P ＜0.05)。而血链菌10556与S34相比较，及血链菌10557与H7-4相比较，均 无显著性差异(P＞0.05)。提示以上四种血链菌菌株 均有合成PABAR的能力，不同菌株产生PABA的能力不完全相同。以上结果为进一步研究血链 菌产生PABA的影响因素及血链菌和变链菌之间的共生关系提供了实验依据。

This study was intended to compare the capacities of different strains of Strep. sanguis for P-Aminobenzoic acid (PABA) production. The synthesis of P ABA during the growth of four strains of Strep. sanguis was measured by the reve rsed-phase high-performance liquid chromatographic method. The results showed t hat the concentrations of PABA synthesized by S. sanguis 10556, S. sanguis 10557 ,S. sanguis S34 and S. sanguis H7-4. Were 1.979*0.081μg/ml, 1.383 ± 0.193μg/ml, 1.983±0.052μg/ml and 1.032±0.229μg/ml, respectively,and in term of PABA concentration , S. sanguis 10556 was significantly different from S. sanguis 10557 and S. sang uis H7-4; S. sanguis S34 was significantly different from S. sangui s 10557 and S. sanguis H7-4. No significant difference was found between S. san guis 10556 and S. sanguis S34, nor between S. sanguis 10557 and S. sanguis H 7-4, either. In conclusion, the method is simple, rapid and accurate. S. sangu is did synthesize PABA, and the difference in ability for PABA formation existed among the four strains of S. sanguis. This study is helpful to researches on the symbiosis between S. sanguis and S. muntans and to determination of their role in the microbial homeostasis of dental plaque.