TY - JOUR
T1 - Epigallocatechin gallate remodels overexpressed functional amyloids in pseudomonas aeruginosa and increases biofilm susceptibility to antibiotic treatment
AU - Stenvang, Marcel R.
AU - Dueholm, Morten S.
AU - Vad, Brian S
AU - Seviour, Thomas
AU - Zeng, Guanghong
AU - Geifman-Shochat, Susana
AU - Søndergaard, Mads T.
AU - Christiansen, Gunna
AU - Meyer, Rikke Louise
AU - Kjelleberg, Staffan
AU - Nielsen, Per Halkjær
AU - Otzen, Daniel E.
PY - 2016/12/16
Y1 - 2016/12/16
N2 - Epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea. It has antimicrobial properties and disrupts the ordered structure of amyloid fibrils involved in human disease. The antimicrobial effect of EGCG against the opportunistic pathogen Pseudomonas aeruginosa has been shown to involve disruption of quorum sensing (QS). Functional amyloid fibrils in P. aeruginosa (Fap) are able to bind and retain quorum-sensing molecules, suggesting that EGCG interferes with QS through structural remodeling of amyloid fibrils. Here we show that EGCG inhibits the ability of Fap to form fibrils; instead, EGCG stabilizes protein oligomers. Existing fibrils are remodeled by EGCG into non-amyloid aggregates. This fibril remodeling increases the binding of pyocyanin, demonstrating a mechanism by which EGCG can affect the QS function of functional amyloid. EGCG reduced the amyloid-specific fluorescent thioflavin T signal in P. aeruginosa biofilms at concentrations known to exert an antimicrobial effect. Nanoindentation studies showed that EGCG reduced the stiffness of biofilm containing Fap fibrils but not in biofilm with little Fap. In a combination treatment with EGCG and tobramycin, EGCG had a moderate effect on the minimum bactericidal eradication concentration against wild-type P. aeruginosa biofilms, whereas EGCG had a more pronounced effect when Fap was overexpressed. Our results provide a direct molecular explanation for the ability of EGCG to disrupt P. aeruginosa QS and modify its biofilm and strengthens the case forEGCGas a candidate in multidrug treatment of persistent biofilm infections.
AB - Epigallocatechin-3-gallate (EGCG) is the major polyphenol in green tea. It has antimicrobial properties and disrupts the ordered structure of amyloid fibrils involved in human disease. The antimicrobial effect of EGCG against the opportunistic pathogen Pseudomonas aeruginosa has been shown to involve disruption of quorum sensing (QS). Functional amyloid fibrils in P. aeruginosa (Fap) are able to bind and retain quorum-sensing molecules, suggesting that EGCG interferes with QS through structural remodeling of amyloid fibrils. Here we show that EGCG inhibits the ability of Fap to form fibrils; instead, EGCG stabilizes protein oligomers. Existing fibrils are remodeled by EGCG into non-amyloid aggregates. This fibril remodeling increases the binding of pyocyanin, demonstrating a mechanism by which EGCG can affect the QS function of functional amyloid. EGCG reduced the amyloid-specific fluorescent thioflavin T signal in P. aeruginosa biofilms at concentrations known to exert an antimicrobial effect. Nanoindentation studies showed that EGCG reduced the stiffness of biofilm containing Fap fibrils but not in biofilm with little Fap. In a combination treatment with EGCG and tobramycin, EGCG had a moderate effect on the minimum bactericidal eradication concentration against wild-type P. aeruginosa biofilms, whereas EGCG had a more pronounced effect when Fap was overexpressed. Our results provide a direct molecular explanation for the ability of EGCG to disrupt P. aeruginosa QS and modify its biofilm and strengthens the case forEGCGas a candidate in multidrug treatment of persistent biofilm infections.
UR - http://www.scopus.com/inward/record.url?scp=85006247399&partnerID=8YFLogxK
U2 - 10.1074/jbc.M116.739953
DO - 10.1074/jbc.M116.739953
M3 - Journal article
AN - SCOPUS:85006247399
SN - 0021-9258
VL - 291
SP - 26540
EP - 26553
JO - The Journal of Biological Chemistry
JF - The Journal of Biological Chemistry
IS - 51
ER -