Phenol, 2,4-bis(1,1-dimethylethyl) of marine bacterial origin inhibits quorum sensing mediated biofilm formation in the uropathogen Serratia marcescens.
Intercellular communication in bacteria (quorum sensing, QS) is an important phenomenon in disease dissemination and pathogenesis, which controls biofilm formation also. This study reports the anti-QS and anti-biofilm efficacy of seaweed Gracilaria gracilis associated Vibrio alginolyticus G16 against Serratia marcescens. Purification and mass spectrometric analysis revealed the active principle as phenol, 2,4-bis(1,1-dimethylethyl) [PD]. PD affected the QS regulated virulence factor production in S. marcescens and resulted in a significant (p < 0.05) reduction in biofilm (85%), protease (41.9%), haemolysin (69.9%), lipase (84.3%), prodigiosin (84.5%) and extracellular polysaccharide (84.62%) secretion without hampering growth, as evidenced by XTT [2,3-bis (2-methoxy-4-nitro-5-sulfophenyl)-2H-tetrazolium-5-carboxanilide] assay. qPCR analysis confirmed the down-regulation of the fimA, fimC, flhD and bsmA genes involved in biofilm formation. Apart from biofilm inhibition and disruption, PD increased the susceptibility of S. marcescens to gentamicin when administered synergistically, which opens another avenue for combinatorial therapy where PD can be used to enhance the efficacy of conventional antibiotics.
a Department of Biotechnology , Alagappa University , Science Campus, Karaikudi , TN , India.
Alwar Ramanujam
AR
Padmavathi
Bose
B
Abinaya
Shunmugiah Karutha
SK
Pandian
D000900:Anti-Bacterial Agents / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D018441:Biofilms / Q000187:drug effects* / Q000254:growth & development; D005839:Gentamicins / Q000494:pharmacology; D013058:Mass Spectrometry; D008826:Microbial Sensitivity Tests; D010636:Phenols / Q000737:chemistry / Q000302:isolation & purification / Q000494:pharmacology*; D053038:Quorum Sensing / Q000187:drug effects*; D012706:Serratia marcescens / Q000187:drug effects* / Q000502:physiology; D015398:Signal Transduction; D044149:Vibrio alginolyticus / Q000737:chemistry*; D037521:Virulence Factors / Q000378:metabolism
D000900:Anti-Bacterial Agents; D005839:Gentamicins; D010636:Phenols; D037521:Virulence Factors
anti-biofilm; biofilm disruption; phenol, 2,4-bis(1,1-dimethylethyl); quorum sensing inhibition; seaweed associated bacteria