Sex Pheromones and the Plasmid-Encoded Mating Response in Enterococcus faecalis

1993 ◽  
pp. 349-367 ◽  
Author(s):  
Don B. Clewell
Keyword(s):  
Enterococcus Faecalis ◽  
Sex Pheromones ◽  
Mating Response

scholarly journals Functional Analysis of TraA, the Sex Pheromone Receptor Encoded by pPD1, in a Promoter Region Essential for the Mating Response in Enterococcus faecalis

2002 ◽  
Vol 184 (22) ◽  
pp. 6343-6350 ◽  
Author(s):  
Takaaki Horii ◽  
Hiromichi Nagasawa ◽  
Jiro Nakayama
Keyword(s):  
Sex Pheromone ◽  
Enterococcus Faecalis ◽  
Intergenic Region ◽  
Recipient Cell ◽  
Donor Cell ◽  
Northern Analysis ◽  
Mobility Shift ◽  
Transcriptional Initiation ◽  
Mating Response ◽  
Gel Mobility Shift

ABSTRACT Conjugative transfer of a bacteriocin plasmid, pPD1, of Enterococcus faecalis is induced in response to a peptide sex pheromone, cPD1, secreted from plasmid-free recipient cells. cPD1 is taken up by a pPD1 donor cell and binds to an intracellular receptor, TraA. Once a recipient cell acquires pPD1, it starts to produce an inhibitor of cPD1, termed iPD1, which functions as a TraA antagonist and blocks self-induction in donor cells. In this study, we discuss how TraA transduces the signal of cPD1 to the mating response. Gel mobility shift assays indicated that TraA is bound to a traA-ipd intergenic region, which is essential for cPD1 response. DNase I footprinting analysis suggested the presence of one strong (tab1) and two weak (tab2 and tab3) TraA-binding sites in the intergenic region. Primer extension analysis implied that the transcriptional initiation sites of traA and ipd were located in the intergenic region. Northern analysis showed that cPD1 upregulated and downregulated transcription of ipd and traA, respectively. The circular permutation assay showed that TraA bent a DNA fragment corresponding to the tab1 region, and its angle was changed in the presence of cPD1 or iPD1. From these data, we propose a model that TraA changes the conformation of the tab1 region in response to cPD1 and upregulates the transcription of ipd, which may lead to expression of genes required for the mating response.

scholarly journals A pAD1-Encoded Small RNA Molecule, mD, Negatively Regulates Enterococcus faecalis Pheromone Response by Enhancing Transcription Termination

2000 ◽  
Vol 182 (4) ◽  
pp. 1062-1073 ◽  
Author(s):  
Haruyoshi Tomita ◽  
Don B. Clewell
Keyword(s):  
Enterococcus Faecalis ◽  
Structural Genes ◽  
Pheromone Response ◽  
Genetic Studies ◽  
Mating Response ◽  
Aggregation Substance ◽  
Transcriptional Termination ◽  
Inhibitor Peptide ◽  
A Site ◽  
Direction Opposite

ABSTRACT pAD1 is a 60-kb hemolysin-bacteriocin plasmid in Enterococcus faecalis that encodes a conjugative mating response to a peptide sex pheromone, cAD1, secreted by plasmid-free bacteria. The pheromone response is regulated by two proteins: TraE1, which positively regulates all or most conjugative structural genes, and TraA, which negatively regulates traE1. TraA binds to pAD1 DNA at theiad (encoding the inhibitor peptide iAD1) promoter but is released upon binding to imported pheromone. This leads to enhanced transcription through two closely spaced downstream terminators (t1 and t2) into traE1. TraE1 is believed to then upregulate itself from a site located within t2; thus, a small amount of transcription through t1-t2 could lead to overall induction. It is important therefore that the t1-t2 terminators be tightly controlled to keep the response shut down in the absence of pheromone. A small (200-nucleotide) RNA molecule designated mD is encoded just upstream of t1 by a determinant (traD) oriented in the direction opposite to that of transcripts utilizing t1. mD is expressed at high levels in the uninduced state, but it decreases significantly upon induction. Here we present results of genetic studies relating to the activity of t1-t2 and show that mD strongly enhances transcriptional termination at t1. The mD activity is shown to influence transcription well downstream and can affect the determinant for aggregation substance asa1. The phenomenon is specific in that there is no effect of mD on the unrelated pheromone-responding plasmids pPD1 and pCF10.

scholarly journals Sex pheromones and plasmid transfer in Enterococcus faecalis

Plasmid ◽  
1989 ◽  
Vol 21 (3) ◽  
pp. 175-184 ◽  
Author(s):  
Don B. Clewell ◽  
Keith E. Weaver
Keyword(s):  
Enterococcus Faecalis ◽  
Sex Pheromones ◽  
Plasmid Transfer

scholarly journals Characterization of a class of nonformylated Enterococcus faecalis-derived neutrophil chemotactic peptides: the sex pheromones.

1990 ◽  
Vol 87 (1) ◽  
pp. 66-70 ◽  
Author(s):  
P. Sannomiya ◽  
R. A. Craig ◽  
D. B. Clewell ◽  
A. Suzuki ◽  
M. Fujino ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Sex Pheromones ◽  
Chemotactic Peptides

scholarly journals An ABC Transporter Is Required for Secretion of Peptide Sex Pheromones in Enterococcus faecalis

mBio ◽  
2014 ◽  
Vol 5 (5) ◽  
Author(s):  
Sriram Varahan ◽  
Nathan Harms ◽  
Michael S. Gilmore ◽  
John M. Tomich ◽  
Lynn E. Hancock
Keyword(s):  
Enterococcus Faecalis ◽  
Abc Transporter ◽  
Sex Pheromones ◽  
Cell Communication ◽  
Antibiotic Resistance Genes ◽  
The United States ◽  
Peptide Transporter ◽  
Bacterial Killing ◽  
Content Type ◽  
Biofilm Development

ABSTRACTEnterococci are leading causes of hospital-acquired infection in the United States and continue to develop resistances to new antibiotics. ManyEnterococcus faecalisisolates harbor pheromone-responsive plasmids that mediate horizontal transfer of even large blocks of chromosomal genes, resulting in hospital-adapted strains over a quarter of whose genomes consist of mobile elements. Pheromones to which the donor cells respond derive from lipoprotein signal peptides. Using a novel bacterial killing assay dependent on the presence of sex pheromones, we screened a transposon mutant library for functions that relate to the production and/or activity of the effector pheromone. Here we describe a previously uncharacterized, but well-conserved, ABC transporter that contributes to pheromone production. Using three distinct pheromone-dependent mating systems, we show that mutants defective in expressing this transporter display a 5- to 6-order-of-magnitude reduction in conjugation efficiency. In addition, we demonstrate that the ABC transporter mutant displays an altered biofilm architecture, with a significant reduction in biofilm biomass compared to that of its isogenic parent, suggesting that pheromone activity also influences biofilm development. The conservation of this peptide transporter across theFirmicutessuggests that it may also play an important role in cell-cell communication in other species within this important phylum.IMPORTANCEEnterococcus faecalisranks as one of the leading causes of hospital-associated infections. Strains possessing resistance to multiple antibiotics are becoming all too common in clinical settings. Pheromone-responsive plasmids play an important role in harboring and disseminating these antibiotic resistance genes. Here we have identified a novel ABC transporter that is responsible for the secretion of peptide pheromones, which enables communication between cells to mediate plasmid transfer. We have also shown that this transporter is important for biofilm formation, providing a strong rationale for its use as a viable therapeutic target which could be targeted to curb infection, as well as the spread of existing drug resistance.

Identification of aggregation substances of Enterococcus faecalis cells after induction by sex pheromones

1989 ◽  
Vol 151 (6) ◽  
pp. 486-490 ◽  
Author(s):  
Dominique Galli ◽  
Reinhard Wirth ◽  
Gerhard Wanner
Keyword(s):  
Enterococcus Faecalis ◽  
Sex Pheromones

Purification of sex pheromones specific for pMB1 and pMB2 plasmids of Enterococcus faecalis S-48

1995 ◽  
Vol 41 (7) ◽  
pp. 629-632 ◽  
Author(s):  
R. Quirantes ◽  
E. Valdivia ◽  
I. Martín ◽  
M. Martínez-Bueno ◽  
M. Maqueda ◽  
...  
Keyword(s):  
Enterococcus Faecalis ◽  
Type Strain ◽  
Sex Pheromones ◽  
Wild Type Strain ◽  
Reversed Phase ◽  
Wild Type ◽  
Pheromone Response ◽  
Conjugative Plasmids ◽  
In The Wild ◽  
Key Words Pheromone

The strain Enterococcus faecalis S-48 carries two large conjugative plasmids (pMB1 and pMB2) encoding for antagonistic substances. The pheromone response of these two plasmids was established by purifying the corresponding sex pheromones, using conventional reversed-phase columns. Plasmid pMB1 responds to pheromone cCF10. Plasmid pMB2 responds to a pheromone with an amino acid sequence identical to that of cPD1 (Phe-Leu-Val-Met-Phe-Leu-Ser-Gly). The two pheromone-responding plasmids coexist in a stable fashion in the wild-type strain E. faecalis S-48.Key words: pheromone response, Enterococcus faecalis, conjugative plasmids.

scholarly journals Characterization of an Active Partition System for the Enterococcus faecalis Pheromone-Responding Plasmid pAD1

2007 ◽  
Vol 189 (23) ◽  
pp. 8546-8555 ◽  
Author(s):  
Maria Victoria Francia ◽  
Keith E. Weaver ◽  
Patricia Goicoechea ◽  
Patricia Tille ◽  
Don B. Clewell
Keyword(s):  
Enterococcus Faecalis ◽  
Consensus Sequence ◽  
Protein A ◽  
Mobility Shift ◽  
Mating Response ◽  
Partition System ◽  
Dnase I Footprinting ◽  
Low Copy Number ◽  
Replication Initiator

ABSTRACT Enterococcus faecalis plasmid pAD1 is a 60-kb conjugative, low-copy-number plasmid that encodes a mating response to the peptide sex pheromone cAD1 and a cytolytic exotoxin that contributes to virulence. Although aspects of conjugation have been studied extensively, relatively little is known about the control of pAD1 maintenance. Previous work on pAD1 identified a 5-kb region of DNA sufficient to support replication, copy control, and stable inheritance (K. E. Weaver, D. B. Clewell, and F. An, J. Bacteriol. 175:1900-1909, 1993), and recently, the pAD1 replication initiator (RepA) and the origin of vegetative replication (oriV) were characterized (M. V. Francia, S. Fujimoto, P. Tille, K. E. Weaver, and D. B. Clewell, J. Bacteriol. 186:5003-5016, 2004). The present study focuses on the adjacent determinants repB and repC, as well as a group of 25 8-bp direct repeats (iterons with the consensus sequence TAGTARRR) located between the divergently transcribed repA and repB. Through mutagenesis and trans-complementation experiments, RepB (a 33-kDa protein, a member of the ParA superfamily of ATPases) and RepC (a protein of 14.4 kDa) were shown to be required for maximal stabilization. Both were active in trans. The iteron region was shown to act as the pAD1 centromere-like site. Purified RepC was shown by DNA mobility shift and DNase I footprinting analyses to interact in a sequence-specific manner with the iteron repeats upstream of the repBC locus. The binding of RepC to the iteron region was shown to be modified by RepB in the presence of ATP via a possible interaction with the RepC-iteron complex. RepB did not bind to the iteron region in the absence of RepC.

scholarly journals Identification of the cAD1 Sex Pheromone Precursor in Enterococcus faecalis

2002 ◽  
Vol 184 (7) ◽  
pp. 1880-1887 ◽  
Author(s):  
Florence Y. An ◽  
Don B. Clewell
Keyword(s):  
Amino Acid ◽  
Sex Pheromone ◽  
Enterococcus Faecalis ◽  
Signal Sequence ◽  
Growth Conditions ◽  
Pheromone Biosynthesis ◽  
Virulence Plasmid ◽  
Gene Encoding ◽  
Mating Response ◽  
Zinc Metalloprotease

ABSTRACT The Enterococcus faecalis virulence plasmid pAD1 encodes a mating response induced by exposure to an octapeptide sex pheromone, cAD1, secreted by plasmid-free enterococci. The determinant for the pheromone in E. faecalis FA2-2, designated cad, was found to encode a 309-amino-acid lipoprotein precursor with the last 8 residues of its 22-amino acid signal sequence representing the cAD1 moiety. The lipoprotein moiety contained two 77-amino-acid repeats (70% identity) separated by 45 residues. The nonisogenic E. faecalis strain V583 determinant encodes a homologous precursor protein, but it differs at two amino acid positions, both of which are located within the pheromone peptide moiety (positions 2 and 8). Construction of a variant of strain FA2-2 containing the differences present in V583 resulted in cells that did not produce detectable cAD1. The mutant appeared normal under laboratory growth conditions, and while significantly reduced in recipient potential, when carrying pAD1 it exhibited a normal mating response. A mutant of FA2-2 with a truncated lipoprotein moiety appeared normal with respect to recipient potential and, when carrying plasmid DNA, donor potential. A gene encoding a protein designated Eep, believed to be a zinc metalloprotease, had been previously identified as required for pheromone biosynthesis and was believed to be involved in the processing of a pheromone precursor. Our new observation that the pAD1-encoded inhibitor peptide, iAD1, whose precursor is itself a signal sequence, is also dependent on Eep is consistent with the likelihood that such processing occurs at the amino terminus of the cAD1 moiety.

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