Kim Soo-Kyoung, Park Ha-Young, Lee Joon-Hee
Department of Pharmacy, College of Pharmacy, Pusan National University, Busan, South Korea.
Department of Pharmacy, College of Pharmacy, Pusan National University, Busan, South Korea
Appl Environ Microbiol. 2015 Apr;81(7):2328-38. doi: 10.1128/AEM.03551-14. Epub 2015 Jan 23.
Anthranilate and indole are alternative degradation products of tryptophan, depending on the bacterial species. While indole enhances the biofilm formation of Pseudomonas aeruginosa, we found that anthranilate, the tryptophan degradation product of P. aeruginosa, had an opposite effect on P. aeruginosa biofilm formation, in which anthranilate deteriorated the mushroom structure of biofilm. The anthranilate effect on biofilm formation was differentially exerted depending on the developmental stage and the presence of shear force. Anthranilate slightly accelerated the initial attachment of P. aeruginosa at the early stage of biofilm development and appeared to build more biofilm without shear force. But anthranilate weakened the biofilm structure in the late stage, deteriorating the mushroom structure of biofilms with shear force to make a flat biofilm. To investigate the interplay of anthranilate with indole in biofilm formation, biofilms were cotreated with anthranilate and indole, and the results showed that anthranilate antagonized the biofilm-enhancing effect of indole. Anthranilate was able to deteriorate the preformed biofilm. The effect of anthranilate and indole on biofilm formation was quorum sensing independent. AntR, a regulator of anthranilate-degrading metabolism was synergistically activated by cotreatment with anthranilate and indole, suggesting that indole might enhance biofilm formation by facilitating the degradation of anthranilate. Anthranilate slightly but significantly affected the cyclic diguaniylate (c-di-GMP) level and transcription of major extracellular polysaccharide (Psl, Pel, and alginate) operons. These results suggest that anthranilate may be a promising antibiofilm agent and antagonize the effect of indole on P. aeruginosa biofilm formation.
邻氨基苯甲酸和吲哚是色氨酸的不同降解产物，具体取决于细菌种类。虽然吲哚可增强铜绿假单胞菌的生物膜形成，但我们发现，作为铜绿假单胞菌色氨酸降解产物的邻氨基苯甲酸对铜绿假单胞菌生物膜形成具有相反的作用，其中邻氨基苯甲酸会破坏生物膜的蘑菇状结构。邻氨基苯甲酸对生物膜形成的影响因发育阶段和剪切力的存在而有所不同。在生物膜发育早期，邻氨基苯甲酸略微加速了铜绿假单胞菌的初始附着，并且在没有剪切力的情况下似乎能形成更多生物膜。但在后期，邻氨基苯甲酸会削弱生物膜结构，破坏有剪切力作用下生物膜的蘑菇状结构，使其变为扁平生物膜。为了研究邻氨基苯甲酸与吲哚在生物膜形成中的相互作用，将生物膜用邻氨基苯甲酸和吲哚共同处理，结果表明邻氨基苯甲酸拮抗了吲哚对生物膜的增强作用。邻氨基苯甲酸能够破坏预先形成的生物膜。邻氨基苯甲酸和吲哚对生物膜形成的影响与群体感应无关。邻氨基苯甲酸降解代谢的调节因子AntR通过与邻氨基苯甲酸和吲哚共同处理而被协同激活，这表明吲哚可能通过促进邻氨基苯甲酸的降解来增强生物膜形成。邻氨基苯甲酸对环二鸟苷酸（c-di-GMP）水平和主要细胞外多糖（Psl、Pel和藻酸盐）操纵子的转录有轻微但显著的影响。这些结果表明，邻氨基苯甲酸可能是一种有前景的抗生物膜剂，并能拮抗吲哚对铜绿假单胞菌生物膜形成的作用。
