Ghosh Saheli, Qureshi Asifa, Purohit Hemantj
Environmental Biotechnology and Genomics Division, CSIR-National Environmental Engineering Research Institute (NEERI), Nehru Marg, Nagpur 440 020, India.
J Biosci. 2019 Mar;44(1).
Biofilm genesis by sp is associated with biofouling in natural settings. D-Tryptophan (D-Trp) inhibits bacterial biofilms and have been proposed for biofouling control applications. In this study, D-Trp significantly inhibited and attachment (biofilm formation) rates on polystyrene96-well microtiter plates in comparison with L-Tryptophan (L-Trp) and mixtures of D-/L-Tryptophan (D-/L-Trp). Theinhibitory effect was greater on P. mendocina,where the rate of cell adherence was declined to 8.79105cells/h from8.09106cells/h (control) inP. mendocina.InS. aureusit was declined to 4.29107cells/h from 9.29107cells/h(control) at 1 mM concentration. It hindered the intracellular communication and adherence in both the strains, as con-firmed by SEM and real time PCR analysis. Addition of D-Trp to preformed biofilms also caused partial disassembly. Intraand interbacterial aggregation were decreased subsequently upon treatment with D-Trp. It repressed the genes involved incell-cell communication, which could be responsible for the diminished biofilm formation of the selected strains. HenceD-Tryptophan has proved to be an effective strategy to control biofilm and may support in the development of surfacecoating technologies.
由sp引起的生物膜形成与自然环境中的生物污垢有关。D-色氨酸（D-Trp）可抑制细菌生物膜，已被提议用于生物污垢控制应用。在本研究中，与L-色氨酸（L-Trp）以及D-/L-色氨酸混合物（D-/L-Trp）相比，D-Trp显著抑制了聚苯乙烯96孔微量滴定板上的细菌附着（生物膜形成）速率。对门多萨假单胞菌的抑制作用更强，在门多萨假单胞菌中，细胞黏附速率从对照的8.09×10⁶ 个细胞/小时降至8.79×10⁵ 个细胞/小时。在金黄色葡萄球菌中，在1 mM浓度下，细胞黏附速率从对照的9.29×10⁷ 个细胞/小时降至4.29×10⁷ 个细胞/小时。扫描电子显微镜（SEM）和实时聚合酶链反应（PCR）分析证实，它阻碍了这两种菌株的细胞内通讯和黏附。向预先形成的生物膜中添加D-Trp也会导致部分解体。用D-Trp处理后，细菌内和细菌间的聚集随后减少。它抑制了参与细胞间通讯的基因，这可能是所选菌株生物膜形成减少的原因。因此，D-色氨酸已被证明是控制生物膜的有效策略，可能有助于表面涂层技术的发展。
