This study revealed that a Pseudomonas aeruginosa tonB1 mutant was unable to produce a mature biofilm and showed reduced swarming and twitching motilities compared with the parent strain. The tonB1 mutant was also found to produce significantly lower cell-free and cell-associated levels of the quorum sensing (QS) signal molecule 3-oxo-C12-AHL. Altered biofilm and motility phenotypes were restored to wildtype with the addition of exogenous N-acylhomoserine lactones. These functions were independent of the role of TonB1 in iron uptake. This is the first time that a link has been established between TonB1 activity and QS.
Download full-text PDF |
Source |
---|---|
http://dx.doi.org/10.1111/j.1574-6968.2007.00845.x | DOI Listing |
mSphere
December 2021
Institute for Molecular Biosciences, Goethe University Frankfurt, Frankfurt am Main, Germany.
The TonB-dependent transport of scarcely available substrates across the outer membrane is a conserved feature in Gram-negative bacteria. The plasma membrane-embedded TonB-ExbB-ExbD accomplishes complex functions as an energy transducer by physically interacting with TonB-dependent outer membrane transporters (TBDTs). TonB mediates structural rearrangements in the substrate-loaded TBDTs that are required for substrate translocation into the periplasm.
View Article and Find Full Text PDFInfect Immun
January 2022
Department of Microbiology and Immunology, Brody School of Medicine, East Carolina Universitygrid.255364.3, Greenville, North Carolina, USA.
The opportunistic, anaerobic pathogen and commensal of the human large intestinal tract, Bacteroides fragilis strain 638R, contains six predicted TonB proteins, termed TonB1-6, four ExbBs orthologs, ExbB1-4, and five ExbDs orthologs, ExbD1-5. The inner membrane TonB/ExbB/ExbD complex harvests energy from the proton motive force (Δp), and the TonB C-terminal domain interacts with and transduces energy to outer membrane TonB-dependent transporters (TBDTs). However, TonB's role in activating nearly one hundred TBDTs for nutrient acquisition in B.
View Article and Find Full Text PDFJ Mol Biol
June 2020
Department of Biochemistry, University of Oxford, South Parks Road, Oxford OX1 3QU, UK. Electronic address:
Pseudomonas aeruginosa is a priority pathogen for the development of new antibiotics, particularly because multi-drug-resistant strains of this bacterium cause serious nosocomial infections and are the leading cause of death in cystic fibrosis patients. Pyocins, bacteriocins of P. aeruginosa, are potent and diverse protein antibiotics that are deployed during bacterial competition.
View Article and Find Full Text PDFAppl Microbiol Biotechnol
May 2019
Joint International Research Laboratory of Animal Health and Food Safety, College of Veterinary Medicine, Nanjing Agricultural University, Nanjing, 210095, Jiangsu, China.
The TonB system functions in iron transport and has been identified in certain Gram-negative bacteria. Recently, we reported three TonB systems in the Aeromonas hydrophila Chinese epidemic strain NJ-35, but the functions of these systems have not been thoroughly elucidated to date. In this study, we investigated the role of these TonB systems in A.
View Article and Find Full Text PDFInfect Immun
April 2019
Department of Science, Roma Tre University, Rome, Italy
is an important nosocomial pathogen. Mechanisms that allow to cause human infection are still poorly understood. Iron is an essential nutrient for bacterial growth , and the multiplicity of iron uptake systems in suggests that iron acquisition contributes to the ability of to cause infection.
View Article and Find Full Text PDFEnter search terms and have AI summaries delivered each week - change queries or unsubscribe any time!