RRNPP-type quorum-sensing systems regulate solvent formation, sporulation and cell motility in Clostridium saccharoperbutylacetonicum

ABSTRACTThe strictly anaerobic bacteriumClostridium acetobutylicumis well known for its ability to convert sugars into organic acids and solvents, most notably the potential biofuel butanol. However, the regulation of its fermentation metabolism, in particular the shift from acid to solvent production, remains poorly understood. The aim of this study was to investigate whether cell-cell communication plays a role in controlling the timing of this shift or the extent of solvent formation. Analysis of the availableC. acetobutylicumgenome sequences revealed the presence of eight putative RNPP-type quorum sensing systems, here designatedqssAtoqssH, each consisting of RNPP-type regulator gene followed by a small open reading frame encoding a putative signalling peptide precursor. The identified regulator and signal peptide precursor genes were designatedqsrAtoqsrHandqspAtoqspH, respectively. Triplicate regulator mutants were generated in strain ATCC 824 for each of the eight systems and screened for phenotypic changes. TheqsrBmutants showed increased solvent formation during early solventogenesis and hence the QssB system was selected for further characterisation. Overexpression ofqsrBseverely reduced solvent and endospore formation and this effect could be overcome by adding short synthetic peptides to the culture medium representing a specific region of the QspB signalling peptide precursor. In addition, overexpression ofqspBincreased the production of acetone and butanol and the initial (48-hour) titre of heat-resistant endospores. Together, these findings establish a role for QssB quorum sensing in the regulation of early solventogenesis and sporulation inC. acetobutylicum.

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Parallel Quorum Sensing Systems Converge to Regulate Virulence in Vibrio cholerae

Cell ◽

10.1016/s0092-8674(02)00829-2 ◽

2002 ◽

Vol 110 (3) ◽

pp. 303-314 ◽

Cited By ~ 453

Author(s):

Melissa B. Miller ◽

Karen Skorupski ◽

Derrick H. Lenz ◽

Ronald K. Taylor ◽

Bonnie L. Bassler

Keyword(s):

Quorum Sensing ◽

Vibrio Cholerae ◽

Sensing Systems

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Interdependence of multi-drug efflux pumps and quorum sensing systems in Pseudomonas aeruginosa

International Journal of Infectious Diseases ◽

10.1016/j.ijid.2014.03.620 ◽

2014 ◽

Vol 21 ◽

pp. 92

Author(s):

K. Ganguly ◽

J.L. Phillips ◽

M.S. Wren ◽

P.E. Pardington ◽

S. Gnanakaran ◽

...

Keyword(s):

Pseudomonas Aeruginosa ◽

Quorum Sensing ◽

Efflux Pumps ◽

Drug Efflux ◽

Sensing Systems ◽

Drug Efflux Pumps

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Pseudomonas aeruginosa Quorum Sensing Systems as Drug Discovery Targets: Current Position and Future Perspectives

Journal of Medicinal Chemistry ◽

10.1021/acs.jmedchem.8b00540 ◽

2018 ◽

Vol 61 (23) ◽

pp. 10385-10402 ◽

Cited By ~ 27

Author(s):

Fadi Soukarieh ◽

Paul Williams ◽

Michael J Stocks ◽

Miguel Cámara

Keyword(s):

Pseudomonas Aeruginosa ◽

Drug Discovery ◽

Quorum Sensing ◽

Future Perspectives ◽

Current Position ◽

Sensing Systems

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Specificity and complexity in bacterial quorum-sensing systems

FEMS Microbiology Reviews ◽

10.1093/femsre/fuw014 ◽

2016 ◽

Vol 40 (5) ◽

pp. 738-752 ◽

Cited By ~ 110

Author(s):

Lisa A. Hawver ◽

Sarah A. Jung ◽

Wai-Leung Ng

Keyword(s):

Quorum Sensing ◽

Sensing Systems ◽

Bacterial Quorum Sensing ◽

Bacterial Quorum

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The Social Life of Aeromonas through Biofilm and Quorum Sensing Systems

Frontiers in Microbiology ◽

10.3389/fmicb.2017.00037 ◽

2017 ◽

Vol 8 ◽

Cited By ~ 28

Author(s):

Emilie Talagrand-Reboul ◽

Estelle Jumas-Bilak ◽

Brigitte Lamy

Keyword(s):

Quorum Sensing ◽

Social Life ◽

Sensing Systems ◽

The Social

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Functional analysis of three AHL autoinducer synthase genes in Mesorhizobium loti reveals the important role of quorum sensing in symbiotic nodulation

Canadian Journal of Microbiology ◽

10.1139/w08-128 ◽

2009 ◽

Vol 55 (2) ◽

pp. 210-214 ◽

Cited By ~ 19

Author(s):

Menghua Yang ◽

Kejing Sun ◽

Lei Zhou ◽

Ruifu Yang ◽

Zengtao Zhong ◽

...

Keyword(s):

Quorum Sensing ◽

Homoserine Lactone ◽

Culture Conditions ◽

Native Plant ◽

Plant Host ◽

Mesorhizobium Loti ◽

Sensing Systems ◽

Regulatory Circuits ◽

Legume Symbiosis ◽

Successful Establishment

One of the most important signal transduction pathways in bacteria, quorum sensing, is involved in many regulatory circuits in rhizobia, especially in the control of communication between rhizobia and their plant hosts. In this study, we identified 3 autoinducer synthase genes — mrlI1, mrlI2, and mrlI3 — in Mesorhizobium loti NZP 2213. We found that MrlI1 and MrlI2 could synthesize distinct N-acyl homoserine lactone (AHL) autoinducers in rich medium cultures, and the expression of mrlI1 was shown to be growth-phase-dependent. MrlI3 did not produce any detectable AHL molecules under the culture conditions tested. To investigate whether these AHL synthases affect nodulation, we examined the nodulation of AHL-deficient mutants on their native plant host Lotus corniculatus and found that the efficiency of nodulation of bacteria with mutations of any of these 3 synthase genes was reduced, suggesting that quorum sensing systems in M. loti may play an important role in successful establishment of rhizobium–legume symbiosis.

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The YebC Family Protein PA0964 Negatively Regulates the Pseudomonas aeruginosa Quinolone Signal System and Pyocyanin Production

Journal of Bacteriology ◽

10.1128/jb.00428-08 ◽

2008 ◽

Vol 190 (18) ◽

pp. 6217-6227 ◽

Cited By ~ 72

Author(s):

Haihua Liang ◽

Lingling Li ◽

Zhaolin Dong ◽

Michael G. Surette ◽

Kangmin Duan

Keyword(s):

Pseudomonas Aeruginosa ◽

Quorum Sensing ◽

Virulence Factors ◽

Response Regulator ◽

Initial Study ◽

Pfam Family ◽

Swarming Motility ◽

Sensing Systems ◽

Family Protein ◽

Pyocyanin Production

ABSTRACT Bacterial pathogenicity is often manifested by the expression of various cell-associated and secreted virulence factors, such as exoenzymes, protease, and toxins. In Pseudomonas aeruginosa, the expression of virulence genes is coordinately controlled by the global regulatory quorum-sensing systems, which includes the las and rhl systems as well as the Pseudomonas quinolone signal (PQS) system. Phenazine compounds are among the virulence factors under the control of both the rhl and PQS systems. In this study, regulation of the phzA1B1C1D1E1 (phzA1) operon, which is involved in phenazine synthesis, was investigated. In an initial study of inducing conditions, we observed that phzA1 was induced by subinhibitory concentrations of tetracycline. Screening of 13,000 mutants revealed 32 genes that altered phzA1 expression in the presence of subinhibitory tetracycline concentrations. Among them, the gene PA0964, designated pmpR ( p qsR-mediated P QS r egulator), has been identified as a novel regulator of the PQS system. It belongs to a large group of widespread conserved hypothetical proteins with unknown function, the YebC protein family (Pfam family DUF28). It negatively regulates the quorum-sensing response regulator pqsR of the PQS system by binding at its promoter region. Alongside phzA1 expression and phenazine and pyocyanin production, a set of virulence factors genes controlled by both rhl and the PQS were shown to be modulated by PmpR. Swarming motility and biofilm formation were also significantly affected. The results added another layer of regulation in the rather complex quorum-sensing systems in P. aeruginosa and demonstrated a clear functional clue for the YebC family proteins.

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