1887

Chapter 7 : Conjugation and Genetic Exchange in Enterococci

MyBook is a cheap paperback edition of the original book and will be sold at uniform, low price.

Preview this chapter:
Zoom in
Zoomout

Conjugation and Genetic Exchange in Enterococci, Page 1 of 2

| /docserver/preview/fulltext/10.1128/9781555817923/9781555812348_Chap07-1.gif /docserver/preview/fulltext/10.1128/9781555817923/9781555812348_Chap07-2.gif

Abstract:

The medical importance of the enterococci is closely related to the propensity of these organisms to participate in the horizontal transfer of determinants for antibiotic resistance and virulence. Conjugative plasmids in enterococci tend to fall into two main groups. Members of one group encode recognition of recipient-produced peptide pheromones that initiate the mating process; the others do not make use of such signals. The pheromone-responding plasmids usually transfer efficiently in broth (liquid) matings, whereas the others transfer relatively poorly under these conditions. An exception is pMGl, a resistance plasmid in that transfers well in broth despite the apparent absence of a pheromone system. Those plasmids that make use of sex pheromones (e.g., pADl and pCFlO) thus far appear to exhibit a narrow host range—primarily and closely related species-although information on this point is very limited. A partial list of pheromone-responding plasmids is presented in this chapter. The formation of mating aggregates relates to the induction of a protein "aggregation substance" (AS), which appears extensively over the donor surface and binds to "enterococcal binding substance" (EBS) on the recipient surface. Conjugative transposons are particularly common in enterococci and streptococci and play an important role in the dissemination of antibiotic resistance in these organisms. It is likely that the enterococci play a significant role as a hardy facultative reservoir of genetic information available to a variety of other genera.

Citation: Clewell D, Dunny G. 2002. Conjugation and Genetic Exchange in Enterococci, p 265-300. In Gilmore M, Clewell D, Courvalin P, Dunny G, Murray B, Rice L (ed), The Enterococci. ASM Press, Washington, DC. doi: 10.1128/9781555817923.ch7

Key Concept Ranking

Bacterial Pathogenesis
0.7477629
Bacterial Proteins
0.7418134
Chromosomal DNA
0.5388173
0.7477629
Highlighted Text: Show | Hide
Loading full text...

Full text loading...

Figures

Image of Figure 1
Figure 1

Expression of pCF10-encoded surface proteins observed by field emission scanning electron microscopy. The cells shown are from cultures of isogenic strains of carrying either the shuttle vector pWM402 (right panel) or pINY1801 (a chimeric plasmid containing the cloned [surface exclusion protein, Sec10]) and [aggregation substance, Asc10] genes of pCFlO cloned into pWM402). The latter plasmid confers constitutive expression of Asc10 and Sec10 on its host cell ( ). The cells were preserved by a cryofixation procedure similar to that described by Erlandsen et al. ( ). Note the smooth appearance of the bacterial cell surface (right panel) and surface display of the plasmid-encoded proteins as discrete entities with well-defined structural features. Micrographs were kindly supplied by Dr. Stanley Erlandsen, University of Minnesota.

Citation: Clewell D, Dunny G. 2002. Conjugation and Genetic Exchange in Enterococci, p 265-300. In Gilmore M, Clewell D, Courvalin P, Dunny G, Murray B, Rice L (ed), The Enterococci. ASM Press, Washington, DC. doi: 10.1128/9781555817923.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 2
Figure 2

Production, release, and sensing of enterococcal peptides at the cell surface. In the recipient cell shown at the left, the lipoprotein signal peptide is processed by Eep in the cell membrane and the mature pheromone is secreted to the exterior, where it can diffuse into the extracellular medium or remain associated with the cell wall. The plasinid-containing donor cell depicted on the right can bind exogenous pheromone via the plasmid-encoded, peptide-specific binding protein (PrgZ/TraC) and use the chromosomal-encoded Opp system to import the peptide. This cell retains the ability to produce pheromone; however, the plasmid-encoded regulatory protein (PrgY/TraB) in the membrane reduces the endogenous pheromone, thus blocking an autocrine loop where endogenous pheromone could be immediately bound and reinternalized by the producing cell. In addition, the inhibitor peptide is secreted into the growth medium where it serves to neutralize any pheromone released by the same cell. The level of inhibitor secreted seems to be just enough to neutralize any endogenous peptide, while still allowing for exquisite sensitivity to exogenous pheromone.

Citation: Clewell D, Dunny G. 2002. Conjugation and Genetic Exchange in Enterococci, p 265-300. In Gilmore M, Clewell D, Courvalin P, Dunny G, Murray B, Rice L (ed), The Enterococci. ASM Press, Washington, DC. doi: 10.1128/9781555817923.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 3
Figure 3

Comparison of pADl, pCF10, pPDl, and pAM373 in regions that include determinants that relate to regulation of the pheromone response. ORFs indicated by similar colors are homologues in the different plasmids.

Citation: Clewell D, Dunny G. 2002. Conjugation and Genetic Exchange in Enterococci, p 265-300. In Gilmore M, Clewell D, Courvalin P, Dunny G, Murray B, Rice L (ed), The Enterococci. ASM Press, Washington, DC. doi: 10.1128/9781555817923.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 4
Figure 4

Model showing the control circuitry for the pADl and pCFlO pheromone response. P is a primary promoter that is active to some extent even in the uninduced state, giving rise to m3 (for pADl) and Qs (for pCF10), which are terminated at t/IRS1 (noted as 1 in the figure). Induction results in up-regulation from P, which gives rise to significant amounts of m3* (for pADl) and QL (for pCF10), which are terminated at t/IRS2 (noted as 2 in the figure). Induction also results in extension through t/IRS2 and into regions that include determinants that positively regulate conjugation genes. The positive regulators appear to differ significantly for the two plasmids. The short component of the speckled transcript represents mD (for pADl) and Qa (for pCF10), which are expressed under the Pa promoter and, at least in the case of pADl, enhance termination at t. Pa is also believed to govern expression of TraA/PrgX, which negatively regulates expression from P and is able to bind to pheromone. Expression from Pa is down-regulated upon induction.

Citation: Clewell D, Dunny G. 2002. Conjugation and Genetic Exchange in Enterococci, p 265-300. In Gilmore M, Clewell D, Courvalin P, Dunny G, Murray B, Rice L (ed), The Enterococci. ASM Press, Washington, DC. doi: 10.1128/9781555817923.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint
Image of Figure 5
Figure 5

Map of the conjugative transposon showing ORFs believed to be related to conjugation. The transposon is approximately 18 kb in length. Apparent relationships with genes/ORFs in the database are noted.

Citation: Clewell D, Dunny G. 2002. Conjugation and Genetic Exchange in Enterococci, p 265-300. In Gilmore M, Clewell D, Courvalin P, Dunny G, Murray B, Rice L (ed), The Enterococci. ASM Press, Washington, DC. doi: 10.1128/9781555817923.ch7
Permissions and Reprints Request Permissions
Download as Powerpoint

References

/content/book/10.1128/9781555817923.chap7
1. An, E. Y.,, and D. B. Clewell. 2002. Identification of the cADl sex pheromone precursor in Enterococcus faecalis. J. Bacterial. 184, in press.
2. An, F. Y.,, and D. B. Clewell. 1994. Characterization of the determinant (traB) encoding sex pheromone shutdown by the hemolysin/bacteriocin plasmid pADl in Enterococcus faecalis. Plasmid 31: 215 221.
3. An, F. Y.,, and D. B. Clewell. 1997. The origin of transfer (onT) of the Enterococcal, pheromone-responding, cytolysin plasmid pADl is located within the repA determinant. Plasmid 37: 87 94.
4. An, F. Y.,, M. C. Sulavik,, and D. B. Clewell. 1999. Identification and characterization of a determinant (eep) on the Enterococcus faecalis chromosome that is involved in production of the peptide sex pheromone cADl. J. Bacterial. 181: 5915 5921.
5. 4a. Antiporta, M. H.,, and G. M. Dunny. 2002. ccFA, the genetic determinant for the cCFlO peptide pheromone in Enterococcus faecalis OG1RF. J. Bacteriol. 184: 1155 1162.
5. Ayoubi, P.,, A. O. Kilic,, and M. N. Vijayakumar. 1991. Tn5253, the pneumococ-cal ω (cat tet) BM6001 element, is a composite structure of two conjugative transposons Tn 5251 and Tn 5252. J. Bacteriol. 173: 1617 1622.
6. Bae, T. 2000. The role of PrgX and Qa RNA in pheromone-inducible prgB expression in enterococcal conjugative plasmid pCF10 . Ph.D. thesis. University of Minnesota, Minneapolis, MN.
7. Bae, T.,, S. Clerc-Bardin,, and G. M. Dunny. 2000. Analysis and expression of prgX, a key negative regulator of the transfer of the Enterococcus faecalis pheromone-inducible plasmid pCFlO. J. Mol. Biol. 297: 861 875.
8. Bae, T.,, and G. M. Dunny. 2001. Dominant-negative mutants of prgX: evidence for a role for PrgX dimerization in negative regulation of pheromone-inducible conjugation. Mol. Microbiol. 39: 1307 1320.
10. 8a. Bae, T.,, B. Kozlowicz,, and G. M. Dunny. 2002. Two targets in pCFlO DNA for PrgX binding: their role in production of Qa and prgX mRNA and in regulation of pheromone-inducible conjugation. J. Mol. Biol. 315: 995 1007.
9. Bastos, M. C. F.,, K. Tanimoto,, and D. B. Clewell. 1997. Regulation of transfer of the Enterococcus faecalis pheromone-responding plasmid pADl: temperature-sensitive transfer mutants and identification of a new regulatory determinant, traD. J. Bacteriol. 179: 3250 3259.
10. Bastos, M. C. F,, H. Tomita,, K. Tanimoto,, and D. B. Clewell. 1998. Regulation of the Enterococcus faecalis pADl-related sex pheromone response: analyses of traD expression and its role in controlling conjugation. Mol. Microbiol. 30: 381 392.
11. Sensing, B. A.,, and G. M. Dunny. 1993. Cloning and molecular analysis of genes affecting expression of binding substance, the recipient-encoded receptor(s) mediating mating aggregate formation in Enterococcus faecalis. J. Bacteriol. 175: 7421 7429.
12. Bensing, B. A.,, and G. M. Dunny. 1997. Pheromone-inducible expression of an aggregation protein in Enterococcus faecalis requires interaction of a plasmid-encoded RNA with components of the ribosome. Mol. Microbiol. 24: 295 308.
13. Bensing, B. A.,, D. A. Manias,, and G. M. Dunny. 1997. Pheromone cCFlO and plasmid pCFlO-encoded regulatory molecules act post-transcriptionally to activate expression of downstream conjugation functions. Mol. Microbiol. 24: 285 294.
14. Bensing, B. A.,, B. J. Meyer,, and G. M. Dunny. 1996. Sensitive detection of bacterial transcription initiation sites and differentiation from RNA processing sites in the pheromone-induced plasmid transfer system of Enterococcus faecalis. Proc. Nat. Acad. Sci. USA 93: 7794 7799.
15. Berg, T.,, N. Firth,, S. Apisiridej,, A. Hettiaratchi,, A. Leelaporn,, and R. A. Skur-ray. 1998. Complete nucleotide sequence of pSK41: evolution of staphylococcal conjugative multiresistance plasmids. J. Bacteriol. 180: 4350 4359.
16. Berg, T.,, N. Firth,, and R. A. Skurray,. 1997. Enterococcal pheromone-like activity derived from a lipoprotein signal peptide encoded by a Staphylococcus aureus plasmid, p. 1041 1044. In T. Horaud,, M. Sicard,, A. Bouve,, and H. de Montelos (eds.), Streptococci and the Host. Plenum Press, New York, N.Y.
17. Borderon, E.,, G. Bieth,, and T. Horodniceanu. 1982. Genetic and physical studies of Streptococcus faecalis hemolysin plasmids. FEMS Microbiol. Lett. 14: 51 55.
18. Brown, M. S.,, J. Ye,, R. B. Rawson,, and J. L. Goldstein. 2000. Regulated intra-membrane proteolysis; a control mechanism conserved from bacteria to humans. Cell 100: 391 398.
19. Bryan, E. M.,, J. H. Staddon,, and G. M. Dunny. Manuscript in preparation.
20. Burdett, V. 1986. Streptococcal tetracycline resistance mediated at the level of protein synthesis. J. Bacteriol. 165: 564 569.
21. Burdett, V. 1990. Nucleotide sequence of the tet(M) gene of Tn926. Nucleic Acids Res. 18: 6137.
22. Burtram, J.,, M. Strata,, and P. Durre. 1991. Natural transfer of conjugative trans-poson Tn926 between gram-positive and gram-negative bacteria, J. Bacteriol. 173: 443 448.
23. Buttaro, B. A.,, M. H. Antiporta,, and G. M. Dunny. 2000. Cell-associated pheromone peptide (cCFlO) production and pheromone inhibition in Enterococcus faecalis. J. Bacteriol. 182: 4926 4933.
24. Buttaro, B. A.,, A. Colwell,, D. A., Manias,, and G. M. Dunny. Submitted for publication.
25. Carias, L. L.,, S. D. Rudin,, C J. Donskey,, and L. B. Rice. 1998. Genetic linkage and cotransfer of a novel, vanB-containing transposon (Tn53#2) and a low-affinity penicillin-binding protein 5 gene in a clinical vancomycin-resistant Enterococcus faecium isolate. J. Bacteriol. 180: 4426 4434.
26. Celli, J.,, C. Poyart,, and R. Trieu-Cuot. 1997. Use of an excision reporter plasmid to study the intracellulair mobility of the conjugative transposon Tn 916 in gram-positive bacteria. Microbiology 143: 1253 1261.
27. Celli, J.,, and P. Trieu-Cuot 1998. Circularization of Tn 916 is required for expression of the transposon-encoded transfer functions: characterization of long tetracycline-inducible transcripts reading through the attachment site. Mol Microbiol. 28: 103 117.
28. Chow, J. W.,, L. A. Thai,, M. B. Perri,, J. A. Vazquez,, S. M. Donabedian,, D. B. Clewell,, and M. J. Zervos. 1993. Plasmid-associated hemolysin and aggregation substance production contributes to virulence in experimental enterococcal endocarditis. Antimicrob. Agents Chemother. 37: 2474 2477.
29. Christie, P. J.,, S. M. Kao,, J. C. Adsit,, and G. M. Dunny. 1988. Cloning and expression of genes encoding pheromone-inducible antigens of Enterococcus (Streptococcus) faecalis. J. Bacteriol. 170: 5161 5168.
30. Christie, P. J.,, R. Z. Korman,, S. A. Zahler,, J. C. Adsit,, and G. M. Dunny. 1987. Two conjugation systems associated with Streptococcus faecalis plasmid pCFlO: identification of a conjugative transposon that transfers between S. faecalis and Bacillus subtilis. J. Bacteriol 169: 2529 2536.
31. Chung, J. W.,, B. A. Bensing,, and G. M. Dunny. 1995. Genetic analysis of a region of the Enterococcus faecalis plasmid pCF10 involved in positive regulation of conjugative transfer functions, J. Bacteriol 177: 2107 2117.
32. Chung, J. W.,, and G. M. Dunny. 1992. Cis-acting, orientation-dependent, positive control system activates pheromone-inducible conjugation functions at distances greater than 10 kilobases upstream from its target in Enterococcus faecalis. Proc. Natl Acad. Set USA 89: 9020 9024.
33. Chung, J. W.,, and G. M. Dunny. 1995. Transcriptional analysis of a region of the Enterococcus faecalis plasmid pCFlO involved in positive regulation of conjugative transfer functions, J. Bacteriol 177: 2118 2124.
34. Clewell, D. B. 1981. Plasmids, drug resistance, and gene transfer in the genus Streptococcus. Microbiol Rev. 45: 401 436.
35. Clewell, D. B. 1990. Movable genetic elements and antibiotic resistance in en-terococci. Eur. J. Clin. Microbiol. Infect. Dis. 9: 90 102.
36. Clewell, D. B. 1993. Bacterial sex pheromone-induced plasmid transfer. Cell 73: 9 12.
39. 37a. Clewell, D. B., 1998. Conjugative transposons, p. 130 139. In F. J. deBrijn,, J. R. Lupinski,, G. M. Weinstock (éd.), Bacterial Genomes, Physical Structure and Analysis. Chapman Hall, New York, N.Y.
37. Clewell, D. B., 1993. Sex pheromones and the plasmid-encoded mating response in Enterococcus faecalis, p. 349 367. In D. B. Clewell (ed.), Bacterial Conjugation. Plenum Press, New York, N.Y.
38. Clewell, D. B., 1999. Sex pheromone systems in enterococci, p. 47 65. In G. M. Dunny, and S. C. Winans (éd.), Cell-Cell Signaling in Bacteria. ASM Press, Washington, D.C.
39. Clewell, D. B.,, F. Y. An,, S. F. Flannagan,, M. Antiporta,, and G. M. Dunny. 2000. Enterococcal sex pheromone precursors are part of signal sequences for surface lipoprotéine. Mol. Microbiol 35: 246 247.
40. Clewell, D. B.,, F. Y. An,, B. A. White,, and C. Gawron-Burke. 1985. Streptococcus faecalis sex pheromone (cAM373) also produced by Staphylococcus aureus and identification of a conjugative transposon (Tn 918). J. Bacteriol 162: 1212 1220.
41. Clewell, D. B.,, and B. L. Brown. 1980. Sex pheromone cADl in Streptococcus faecalis: induction of a function related to plasmid transfer, J. Bacteriol. 143: 1063 1065.
42. Clewell, D. B.,, and S. E. Flannagan,. 1993. The conjugative transposons of gram positive bacteria, p. 369 l393. In D. B. Clewell (éd.), Bacterial Conjugation. Plenum Press, New York, N.Y.
43. Clewell, D. B.,, S. E. Flannagan,, Y. Ike,, J. M. Jones,, and C. Gawron-Burke. 1988. Sequence analysis of termini of conjugative transposon Tn 916. J. Bacteriol. 170: 3046 3052.
44. Clewell, D. B.,, S. E. Flannagan,, and D. D. Jaworski. 1995. Unconstrained bacterial promiscuity: the Tn 916-Tn 2545 family of conjugative transposons. Trends Microbiol. 3: 229 236.
45. Clewell, D. B.,, S. E. Flannagan,, L. A. Zitzow,, Y. A. Su,, P. He,, E. Senghas,, and K. W. Weaver,. 1991. Properties of conjugative transposon Tn 916, p. 39 44. In G. M. Dunny,, P. Cleary,, and L. McKay (ed.), Genetics and Molecular Biology of Streptococci, Lactococci, and Enterococci. American Society for Microbiology, Washington, D.C.
46. Clewell, D. B.,, and C. Gawron-Burke. 1986. Conjugative transposons and the dissemination of antibiotic resistance in streptococci. Annu. Rev. Microbiol. 40: 635 659.
47. Clewell, D. B.,, L. T. Pontius,, F. Y. An,, Y. Ike,, A. Suzuki,, and J. Nakayama. 1990. Nucleotide sequence of the sex pheromone inhibitor (iAD1) determinant of Enterococcus faecalis conjugative plasmid pAD1. Plasmid 24: 156 161.
48. Clewell, D. B.,, P. K. Tomich,, M. C. Gawron-Burke,, A. E. Franke,, Y. Yagi,, and F. Y. An. 1982. Mapping of Streptococcus faecalis plasmids pAD1 and pAD2 and studies relating to transposition of Tn917. J. Bacteriol. 152: 1220 1230.
49. Clewell, D. B.,, and K. E. Weaver. 1989. Sex pheromones and plasmid transfer in Enterococcus faecalis (a review). Plasmid 21: 175 184.
50. Clewell, D. B.,, Y. Yagi,, and B. Bauer. 1975. Plasnüd-determined tetracycline resistance in Streptococcus faecalis: evidence for gene amplification during growth in presence of tetracycline. Proc. Natl. Acad. Set. USA 72: 1720 1724.
51. Clewell, D. B.,, Y. Yagi,, G. M. Dunny,, and S. K. Schultz. 1974. Characterization of three plasmid deoxyribonucleic acid molecules in a strain of Streptococcus faecalis: identification of a plasmid detenrtining erythromycin resistance. J. Bacteriol. 117: 283 289.
52. Clewell, D. B.,, Y. Yagi,, Y. Ike,, R. A. Craig,, B. L. Brown,, and F. An,. 1982. Sex pheromones in Streptococcus faecalis: multiple pheromone systems in strain DS5, similarities of pAD1 and pAMβ1, and mutants of pAD1 altered in conjugative properties, p. 97 100. In D. Schlessinger (éd.), Microbiology 1982. American Society for Microbiology, Washington, D.C.
53. De Boever, E. H. 2001. Genetic and transcriptional analyses of the pheromone response of the Enterococcus faecalis plasmid AM373. Ph.D. dissertation. The University of Michigan, Ann Arbor.
54. De Boever, E. H.,, and D. B.. Clewell. 2001. The Enterococcus faecalis pheromone-responsive plasmid pAM373 does not encode an entry exclusion function. Plasmid 45: 57 60.
55. De Boever, E. H.,, D. B. Clewell,, and C. M. Fraser. 2000. Enterococcus faecalis conjugative plasmid pAM373: complete nucleotide sequence and genetic analyses of sex pheromone response. Mol. Microbiol. 37: 1327 1341.
56. de Lencastr, H.,, A. E. Brown,, M. Chung,, D. Armstrong,, and A. Tomasz. 1999. Role of transposon Tn5482 in the epidemiology of vancomycin-resistant Enterococcus f aecium in the pediatrie oncology unit of a New York City hospital. Microb. Drug Resist. 5: 113 129.
57. Delver, E. P.,, V. U. Kotova,, G. B. Zavilgelsky,, and A. A. Belogurov. 1991. Nucleotide sequence of the gene (ara) encoding the antirestriction protein of plasmid colIb-P9. J. Bacteriol. 173: 5887 5892.
58. Doucet-Populaire, F.,, P. Trieu-Cuot,. I. Dosbaa,, A. Andremont.,, and R. Cour-valin. 1991. Inducible transfer of conjugative transposon Tn1545 from Enterococcus faecalis to Listeria monocytogenes in the digestive tracts of gnotobiotic mice. Antimicrob. Agents Chemother. 35: 185 187.
59. Dunny, G. M. 1990. Genetic functions and cell-cell interactions in the phero-mone-inducible plasmid transfer system of Enterococcus faecalis. Mol. Microbiol. 4: 689 696.
60. Dunny, G. M. 1991. Mating interactions in gram-positive bacteria, p. 9 33. In M. Dworkin (éd.), Microbiol Cell-Cell Interactions. American Society for Microbiology, Washington, D.C.
61. Dunny, G. M.,, M. H. Antiporta,, and H. Hirt. 2001. Peptide pheromone-induced transfer of plasmid pCF10 in Enterococcus faecalis: probing the genetic and molecular basis for specificity of the pheromone response. Peptides 22: 1529 1539.
62. Dunny, G. M.,, B. L. Brown,, and D. B. Clewell. 1978. Induced cell aggregation and mating in Streptococcus faecalis: evidence for a bacterial sex pheromone. Proc. Natl. Acad. Sci. USA 75: 3479 3483.
63. Dunny, G. M.,, and D. B. Clewell. 1975. Transmissible toxin (hemolysin) plasmid in Streptococcus faecalis and its mobilization of a noninfectious drug resistance plasmid. J. Bacteriol. 124: 784 790
64. Dunny, G. M.,, R. A. Craig,, R. L. Carron,, and D. B. Clewell. 1979. Plasmid transfer in Streptococcus faecalis: production of multiple sex pheromones by recipients. Plasmid 2: 454 465.
65. Dunny, G. M.,, C. Funk,, and J. Adsit. 1981. Direct stimulation of the transfer of antibiotic resistance by sex pheromones in Streptococcus faecalis. Plasmid 6: 270 278.
66. Dunny, G. M.,, and B. A. B. Leonard. 1997. Cell-cell communication in gram-positive bacteria. Annu. Rev. Microbiol. 51: 527 564.
67. Dunny, G. M.,, B. A. B. Leonard,, and P. J. Hedberg. 1995. Pheromone-inducible conjugation in Enterococcus faecalis: interbacterial and host-parasite chemical communication. J. Bactenol. 177: 871 876.
68. Dunny, G.,, M. Yuhasz,, and E. Ehrenfeld. 1982. Genetic and physiological analysis of conjugation in Streptococcus faecalis. J. Bacteriol. 151: 855 859.
69. Dunny, G. M.,, D. L. Zimmerman,, and M. L. Tortorello. 1985. Induction of surface exclusion by Streptococcus faecalis sex pheromones: use of monoclonal antibodies to identify an inducible surface antigen involved in the exclusion process. Proc. Natl. Acad. Sci. USA 82: 8582 8586.
70. Ehrenfeld, E. E.,, and D. B. Clewell. 1987. Transfer functions of the Streptococcus faecalis plasmid pAD1: organization of plasmid DNA encoding response to sex pheromone. J. Bacteriol. 169: 3473 3481.
71. Ehrenfeld, E. E.,, R. E. Kessler,, and D. B. Clewell. 1986. Identification of pheromone-induced surface proteins in Streptococcus faecalis and evidence of a role for lipoteichoic acid in formation of mating aggregates. J. Bacteriol. 168: 6 12.
72. Ember, J. A.,, and T. E. Hugli. 1989. Characterization of the human neutrophil response to sex pheromones from Streptococcus faecalis. Am. J. Pathol. 134: 797 805.
73. Erlandsen, S. L., C. Frethem, and Y. Chen. 2000. Field emission scanning electron microscopy (FESEM) entering the 21st century: nanometer resolution and molecular topography of cell structure. J. Histotechnol. 23: 249 259.
74. Firth, N.,, P. D. Fink,, L. Johnson,, and R. A. Skurray. 1994. A lipoprotein signal peptide encoded by the staphylococcal conjugative plasmid pSK41 exhibits an activity resembling that of Enterococcus faecalis pheromone cADl. J. Bacteriol. 176: 5871 5873.
75. Flannagan, S. E.,, and D. B. Clewell. 2002. Identification and characterization of genes encoding sex pheromone cAM373 activity in Enterococcus faecalis and Staphylococcus aureus. Mol. Microbiol., in press.
76. Flannagan, S. E.,, and D. B. Clewell. 1991. Conjugative transfer of Tn916 in Enterococcus faecalis: trans activation of homologous transposons, J. Bacteriol. 173: 7136 7141.
77. Flannagan, S. E.,, L. A. Zitzow,, Y. A. Su,, and D. B. Clewell. 1994. Nucleotide sequence of the 18-kb conjugative transposon Tn 916 from Enterococcus faecalis. Plasmid 32: 350 354.
78. Francia, M. V.,, and D. B. Clewell. 2001. Identification of new oriT sites on the pheromone-responding Enterococcus faecalis plasmids pADl and pAM373. ASM Conference on Cell-Cell Communication, Snowbird, Utah.
79. Francia, M. V.,, W. Haas,, R. Wirth,, E. Samberger,, A. Muscholl-Silberhorn,, M. S. Gilmore,, Y. Ike,, K. E. Weaver,, F. Y. An,, and D. B. Clewell. 2001. Completion of the nucleotide sequence of the Enterococcus faecalis conjugative virulence plasmid pADl and identification of a second transfer origin. Plasmid 46: 117 127.
80. Franke, A. E.,, and D. B. Clewell. 1981. Evidence for a chromosome-borne resistance transposon (Tn916) in Streptococcus faecalis that is capable of "conjugal" transfer in the absence of a conjugative plasmid. J. Bacterial. 145: 494 502.
81. Franke, A. E.,, G. M. Dunny,, B. L. Brown,, F. An,, D. R. Oliver,, S. P. Damle,, and D. B. Clewell,. 1978. Gene transfer in Streptococcus faecalis: evidence for the mobilization of chromosomal determinants by transmissible plasmids, p. 45 47. In D. Schlessinger (éd.), Microbiology 1978. American Society for Microbiology, Washington, D.C.
82. Fujimoto, S.,, and D. B. Clewell. 1998. Regulation of the pADl sex pheromone response of Enterococcus faecalis by direct interaction between the cADl peptide mating signal and the negatively regulating, DNA-binding TraA protein. Proc. Natl. Acad. Set. USA 95: 6430 6435.
83. Fujimoto, S.,, and Y. Ike. 2000. Plasmid-specific DNA binding of TraAs and PrgX of Enterococcus faecalis plasmids pAD1, pPD1, and CF10. First International ASM Conference on Enterococci, Banff, Canada.
84. Fujimoto, S.,, H. Tomita,, E. Wakamatsu,, K. Tanimoto,, and Y. Ike. 1995. Physical mapping of the conjugative bacteriocin plasmid pPD1 of Enterococcus faecalis and identification of the determinant related to the pheromone response, J. Bacteriol. 177: 5574 5581.
85. Galli, D.,, A. Friesenegger,, and R. Wirth. 1992. Transcriptional control of sex-pheromone-inducible genes on plasmid pADl of Enterococcus faecalis and sequence analysis of a third structural gene for (pPDl-encoded) aggregation substance. Mol. Microbiol. 6: 1297 1308.
86. Galli, D.,, F. Lottspeich,, and R. Wirth. 1990. Sequence analysis of Enterococcus faecalis aggregation substance encoded by the sex pheromone plasmid pAD1. Mol. Microbiol. 4: 895 904.
87. Galli, D.,, and R. Wirth. 1991. Comparative analysis of Enterococcus faecalis sex pheromone plasmids identifies a single homologous DNA region which codes for aggregation substance, J. Bacteriol. 173: 3029 3033.
88. Galli, D.,, R. Wirth,, and G. Wanner. 1989. Identification of aggregation substances of Enterococcus faecalis after induction by sex pheromones. Arch. Microbiol. 151: 486 490.
89. Gamier, E.,, S. Taourit,, P. Glaser,, P. Courvalin,, and M. Galimand. 2000. Characterization of transposon Tn1549, conferring VanB-type resistance in Enterococcus spp. Microbiology 146: 1481 1489.
90. Gawron-Burke, M. C.,, and D. B. Clewell. 1982. A transposon in Streptococcus faecalis with fertility properties. Nature 300: 281 284.
91. Gawron-Burke, M. C.,, and D. B. Clewell. 1984. Regeneration of insertionally inactivated streptococcal DNA fragments following excision of Tn916 in Escherichia colt. A strategy for targeting and cloning genes from gram-positive bacteria. J. Bacteriol. 159: 214 221.
92. Gilmore, M. S.,, R. A. Segarra,, M. C. Booth,, C. P. Bogie,, L. R. Hall,, and D. B. Clewell. 1994. Genetic structure of the Enterococcus faecalis plasmid pAD1-encoded cytolytic toxin system and its relationship to lantibiotic determinants. J. Bacteriol. 176: 7335 7344.
93. Guzman, C. A.,, C. Pruzzo,, M. Plate,, M. C. Guardati,, and L. Calegari. 1991. Serum dependent expression of Enterococcus faecalis adhesins involved in the colonization of heart cells. Microb. Pathog. 11: 399 409.
94. Handwerger, S.,, M. J. Pucci,, and A. Kolokathis. 1990. Vancomycin resistance is encoded on a pheromone response plasmid in Enterococcus faecium 228. Antimicrob. Agents Chemother. 34: 358 360.
95. Handwerger, S.,, and J. Skoble. 1995. Identification of chromosomal mobile element conferring high-level vancomycin resistance in Enterococcus faecium. Antimicrob. Agents Chemother. 39: 2446 2453.
96. Heath, D. G.,, F. Y. An,, K. E. Weaver,, and D. B. Clewell. 1995. Phase variation of Enterococcus faecalis pAD1 conjugation functions relates to changes in iteron sequence region. J. Bacteriol. 177: 5453 5459.
97. Heaton, M. P.,, L. E Discotto,, M. J. Pucci,, and S. Handwerger. 1996. Mobilization of vancomycin resistance by transposon-mediated fusion of a VanA plasmid with an Enterococcus faecium sex pheromone-response plasmid. Gene 171: 9 17.
98. Heaton, M. P.,, and S. Handwerger. 1995. Conjugative mobilization of a vancomycin resistance plasmid by a putative Enterococcus faecium sex pheromone response plasmid. Microb. Drug. Resist. 1: 177 183.
99. Hedberg, P. J.,, B. A. B. Leonard,, R. E. Ruhfel,, and G. M. Dunny. 1996. Identification and characterization of the genes of Enterococcus faecalis plasmid pCF10 involved in replication and in negative control of pheromone-inducible conjugation. Plasmid 35: 46 57.
100. Hinerfeld, D.,, and G. Churchward. 2001. Specific binding of integrase to the origin of transfer (oriT) of the conjugative transposon Tn 916. J. Bacteriol. 183: 2947 2951.
101. Hirt, H.,, S. L. Erlandsen,, and G. M. Dunny. 2000. Heterologous inducible expression of Enterococcus faecalis pCFlO aggregation substance AsclO in Lactococcus lactis and Streptococcus gordonii contributes to cell hydrophobicity and adhesion to fibrin. J. Bacteriol. 182: 2299 2306.
102. Hirt, H.,, P. M. Schlievert,, and G. M. Dunny. 2002. In vivo induction of virulence and antibiotic resistance transfer in Enterococcus faecalis mediated by the sex pheromone-sensing system of pCFlO. Infect. Immun. 70: 716 723.
103. Hirt, H.,, G. Wanner,, D. Galli,, and R. Wirth. 1993. Biochemical, immunologi-cal and ultrastructural characterization encoded by Enterococcus faecalis sex-pheromone plasmids. Eur. J. Biochem. 211: 711 716.
104. Hirt, H.,, R. Wirth,, and A. Muscholl. 1996. Comparative analysis of 18 sex pheromone plasmids from Enterococcus faecalis: detection of a new insertion element on pPD1 and implications for the evolution of this plasmid family. Molec. Gen. Genet. 252: 640 647.
105. Hofner, H.,, R. Wirth,, R. Marre,, G. Wanner,, and E. Straube. 1995. Subinhibitory concentrations of daptomycin enhance adherence of Enterococcus faecalis to in vitro cultivated renal tubuloepithelial cells and induce a sex pheromone plasmid-encoded adhesin. Med. Microbiol. Lett. 4: 140 149.
106. Horaud, T.,, G. de Cespedes,, D. Clermont,, E David, and F. Delbos. 1991. Variability of chromosomal genetic elements in streptococci, p. 16 20. In G. M. Dunny,, P. P. Cleary,, and L. L. McKay (ed), Genetics and Molecular Biology of Streptococci, hactococci, and Enterococci. American Society for Microbiology, Washington, D.C.
107. Horaud, T.,, C. Le Bouguenec,, and K. Pepper. 1985. Molecular genetics of resistance to macrolides, lincosamides and streptogramin B (MLS) in streptococci. J. Antimicrob. Chemother. 16: 111 135.
108. Horn, T.,, J. Nakayama,, S. Sakuda,, and H. Nagasawa. 2000. Analysis of tran-scriptional control by sex pheromone receptor, TraA, in Enterococcus faecalis. First International ASM Conference on Enterococci, Banff, Canada.
109. Huycke, M. M.,, M. S. Gilmore,, B. D. Jett,, and J. L. Booth. 1992. Transfer of pheromone-inducible plasmids between Enterococcus faecalis in the Syrian hamster gastrointestinal tract. J. Infect. Dis. 166: 1188 1191.
110. Huycke, M. M.,, D. E Sahm,, and M. S. Gilmore. 1998. Multiple-drug resistant enterococci: the nature of the problem and an agenda for the future. Emerg. Infect. Dis. 4: 239 249.
111. Ike, Y.,, and D. B. Clewell. 1984. Genetic analysis of the pADl pheromone response in Streptococcus faecalis, using transposon Tn927 as an insertional mutagen. J. Bacterial. 158: 777 783.
112. Ike, Y.,, and D. B. Clewell. 1992. Evidence that the hemolysin/bacteriocin phe-notype of Enterococcus faecalis subsp. zymogenes can be determined by plasmids in different incompatibility groups as well as by the chromosome. J. Bacterial. 171: 8172 8177.
113. Ike, Y.,, R. C. Craig,, B. A. White,, Y. Yagi,, and D. B. Clewell. 1983. Modification of Streptococcus faecalis sex pheromones after acquisition of plasmid DNA. Proc. Natl. Acad. Sci. USA 80: 5369 5373.
114. Ike, Y.,, S. E. Flannagan,, and D. B. Clewell. 1992. Hyperhemolytic phenomena associated with insertions of Tn916 into the hemolysin determinant of Enterococcus faecalis plasmid pADl. J. Bacteriol. 174: 1801 1809.
115. Ike, Y.,, H. Hashimoto,, and D. B. Clewell. 1984. Hemolysin of Streptococcus faecalis subspecies zymogenes contributes to virulence in mice. Infect. Immun. 45: 528 530.
116. Ike, Y.,, H. Hashimoto,, and D. B. Clewell. 1987. High incidence of hemolysin production by Enterococcus (Streptococcus) faecalis strains associated with human parenteral infections. J. Clin. Microbiol. 25: 1524 1528.
117. Ike, Y.,, K. Tanimoto,, H. Tomita,, K. Takeuchi,, and S. Fujimoto. 1998. Efficient transfer of the pheromone-independent Enterococcus faecium plasmid pMG1 (Gm r) (65.1 kilobases) to Enterococcus strains during broth mating, J. Bacteriol. 180: 4886 4892.
118. Jacob, A. E.,, G. I. Douglas,, and S. J. Hobbs. 1975. Self-transferable plasmids determining the hemolysin and bacteriocin of Streptococcus faecalis var. zymogenes. J. Bacteriol. 121: 863 872.
119. Jacob, A. E.,, and S. Hobbs. 1974. Conjugal transfer of plasmid-borne multiple antibiotic resistance in Streptococcus faecalis var. zymogenes. J. Bacteriol. 117: 360 372.
120. Jaworski, D. D.,, and D. B. Clewell. 1994. Evidence that coupling sequences play a frequency-detenrrining role in conjugative transposition of Tn916 in Enterococcus faecalis. J. Bacteriol. 176: 3328 3335.
121. Jaworski, D. D.,, and D. B. Clewell. 1995. A functional origin of transfer (oriT) on the conjugative transposon Tn916. J. Bacteriol. 177: 6644 6651.
122. Jaworski, D. D.,, S. E. Flannagan,, and D. B. Clewell. 1996. Analyses of traA, int-Tn, and xis-Tn mutations in the conjugative transposon Tn 916 in Enterococcus faecalis. Plasmid 36: 201 208.
123. Jett, B. D.,, H. G. Jensen,, R. E. Nordquist,, and M. S. Gilmore. 1992. Contribution of the pAD1-encoded cytolysin to the severity of experimental Enterococcus faecalis endophthalmitis. Infect. Immun. 60: 2445 2452.
124. Kao, S.-M.,, S. B. Olmsted,, A. S. Viksnins,, J. C. Gallo,, and G. M. Dunny. 1991. Molecular and genetic analysis of a region of plasmid pCF10 containing positive control genes and structural genes encoding surface proteins involved in pheromone-inducible conjugation in Enterococcus faecalis. J. Bactenol. 173: 7650 7664.
125. Kreft, B.,, R. Marre,, U. Schramm,, and R. Wirth. 1992. Aggregation substance of Enterococcus faecalis mediates adhesion to cultured renal tubular cells. Infect. Immun. 60: 25 30.
126. Le Bouguenec, C.,, G. de Cespedes,, and T. Horaud. 1988. Molecular analysis of a composite chromosomal conjugative element (Tn3701) of Streptococcus pyogenes. J. Bacteriol. 170: 3930 3936.
127. Leonard, B. A. B.,, A. Podbielski,, R J. Hedberg,, and G. M. Dunny. 1996. Enterococcus faecalis pheromone binding protein, PrgZ, recruits a chromosomal oligopeptide permease system to import sex pheromone cCF10 for induction of conjugation. Proc. Natl. Acad. Sci. USA 93: 260 264.
128. Lowe, A. M.,, R A. Lambert,, and A. W. Smith. 1995. Cloning of an Enterococcus faecalis endocarditis antigen: homology with adhesins from some oral streptococci. Infect. Immun. 63: 703 706.
129. Manoil, C.,, and J. Baily. 1997. A simple screen for permissive sites in proteins: analysis of Eschenchia coli lac permease. J. Mol. Biol. 267: 250 263.
130. Maqueda, M.,, R. Quirantes,, I. Martin,, A. Galvez,, M. Martinez-Bueno,, and E. Valdivia. 1997. Chemical signals in gram-positive bacteria: the sex pheromone system in Enterococcus faecalis. Microbiol. Semin. 13: 23 36.
131. Marra, D.,, B. Pethel,, G. Churchward,, and J. R. Scott. 1999. The frequency of conjugative transposition of Tn916 is not determined by the frequency of excision. J. Bacteriol. 181: 5414 5418.
132. Martinez-Bueno, M.,, A. Galvez,, E. Validivia,, and M. Maqueda. 1990. A transferable plasmid associated with AS-48 production in Enterococcus faecalis. J. Bacteriol. 172: 2817 2818.
133. Martinez-Bueno, M.,, M. Maqueda,, A. Galvez,, B. Samyn,, J. V. Beeumen,, J. Coyette,, and E. Valdivia. 1994. Determination of the gene sequence and the molecular structure of the enterococcal peptide antibiotic AS-48. J. Bacteriol. 176: 6334 6339.
134. Mcllwraith, M.,, S. Showsh,, and D. B. Clewell. Unpublished.
135. Mori, M.,, A. Isogai,, Y. Sakagami,, M. Fujino,, C. Kitada,, D. B. Clewell,, and A. Suzuki. 1986. Isolation and structure of Streptococcus faecalis sex pheromone inhibitor, iAD1, that is excreted by donor strains harboring plasmid pAD1. Agric. Biol. Chem. 50: 539 541.
136. Mori, M.,, Y. Sakagami,, Y. Ishii,, A. Isogai,, C. Kitada,, M. Fujino,, J. C. Adsit,, G. M. Dunny,, and A. Suzuki. 1988. Structure of cCF10, a peptide sex pheromone which induces conjugative transfer of the Streptococcus faecalis tetracycline resistance plasmid, pCF10. J. Biol. Chem. 263: 14574 14578.
137. Mori, M.,, Y. Sakagami,, M. Narita,, A. Isogai,, M. Fuji no,, C. Kitada,, R. Craig,, D. Clewell,, and A. Suzuki. 1984. Isolation and structure of the bacterial sex pheromone, cADl, that induces plasmid transfer in Streptococcus faecalis. FEBS Lett 178: 97 100.
138. Mori, M.,, H. Tanaka,, Y. Sakagami,, A. Isogai,, M. Fuji no,, C. Kitada,, D. B. Clewell,, and A. Suzuki. 1987. Isolation and structure of the sex pheromone inhibitor, iPD1, excreted by Streptococcus faecalis donor strains harboring plasmid pPD1. J. Bacteriol 169: 1747 1749.
139. Mori, M.,, H. Tanaka,, Y. Sakagami,, A. Isogai,, M. Fujino, C. Kitada, B. A. White, F. Y. An, D. B. Clewell, and A. Suzuki. 1986. Isolation and structure of the Streptococcus faecalis sex pheromone, cAM373. FEBS Lett. 206: 69 72.
140. Mullany, P.,, M. Pallen,, M. Wilks,, J. R. Stephen,, and S. Tabaqchali. 1996. A group II intron in a conjugative transposon from the gram-positive bacterium, Clostridium difficile. Gene 174: 145 150.
141. Murray, B. E.,, F. An,, and D. B. Clewell. 1988. Plasmids and pheromone response of the β-lactamase producer Streptococcus (Enterococcus) faecalis HH22. Antimicrob. Agents Chemother. 32: 547 551.
142. Muscholl-Silberhorn, A. 1998. Analysis of the clumping-mediating domain(s) of sex pheromone plasmid pADl-encoded aggregation substance. Eur. J. Biochem. 258: 515 520.
143. Muscholl-Silberhorn, A. 1999. Cloning and functional analysis of Asa373, a novel adhesin unrelated to the other sex pheromone plasmid-encoded aggregation substances of Enterococcus faecalis. Mol. Microbiol. 34: 620 630.
144. Muscholl-Silberhorn, A. 2000. Pheromone-regulated expression of sex pheromone plasmid pADl-encoded aggregation substance depends on at least six upstream genes and a cis-acting, orientation-dependent factor. J. Bacteriol. 182: 3816 3825.
145. Muscholl, A.,, D. Galli,, G. Wanner,, and R. Wirth. 1993. Sex pheromone plasmid pADl-encoded aggregation substance of Enterococcus faecalis is positively regulated in trans by traE1. Eur. J. Biochem. 214: 333 338.
146. Muscholl-Silberhorn, A.,, E. Samberger,, and R. Wirth. 1997. Why does Staphylococcus aureus secrete an Enterococcus faecalis-specific pheromone? FEMS Microbiol. Lett. 157: 261 266.
147. Nakayama, J.,, Y. Abe,, A. Isogai,, and A. Suzuki. 1995. Isolation and structure of the Enterococcus faecalis sex pheromone, cOB1, that induces conjugal transfer of the hemolysin/bacteriocin plasmids, pOBl and pYIl. Biosci. Biotech. Biochem. 59: 703 705.
148. Nakayama, J.,, D. B. Clewell,, and A. Suzuki. 1995. Targeted disruption of the PD78 (traF) reduces pheromone-inducible conjugal transfer of the bacteriocin plasmid pPD1 in Enterococcus faecalis. FEMS Microbiol. Lett. 128: 283 288.
149. Nakayama, J.,, G. M. Dunny,, D. B. Clewell,, and A. Suzuki,. 1995. Quantitative analysis for pheromone inhibitor and pheromone shutdown in Enterococcus faecalis, p. 35-38. In J. J. Ferretti,, M. S. Gilmore,, T. R. Klaenhammer,, and F. Brown (eds.), Genetics of Streptococci, Enterococci and Lactococci. Developmental and Biological Standards, vol. 85. Karger, Basel, Switzerland.
150. Nakayama, J.,, S. Igarashi,, H. Nagasawa,, D. B. Clewell,, F. Y. An,, and A. Suzuki. 1996. Isolation and structure of staph-cAM373 produced by Staphylococcus aureus that induces conjugal transfer of Enterococcus faecalis plasmid pAM373. Biosci. Biotech. Biochem. 60: 1038 1039.
151. Nakayama, J.,, Y. Ono,, A. Isogai,, D. B. Clewell,, and A. Suzuki. 1995. Isolation and structure of the sex pheromone inhibitor, ÎAM373, of Enterococcus faecalis. Biosci. Biotech. Biochem. 59: 1358 1359.
152. Nakayama, J.,, R. E. Ruhfel,, G. M. Dunny,, A. Isogai,, and A. Suzuki. 1994. The prgQ gene of the Enterococcus faecalis tetracycline resistance plasmid pCF10 encodes a peptide inhibitor, iCF10. J. Bacteriol 176: 2003 2004.
153. Nakayama, J.,, and A. Suzuki. 1997. Genetic analysis of plasmid-specific pheromone signaling encoded by pPDl in Enterococcus faecalis. Biosci. Biotech. Biochem. 61: 1796 1799.
154. Nakayama, J.,, Y. Takanami,, T. Horii,, S. Sakuda,, and A. Suzuki. 1998. Molecular mechanism of peptide-specific pheromone signaling in Enterococcus faecalis: functions of pheromone receptor TraA and pheromone-binding protein TraC encoded by plasmid pPD1. J. Bacteriol. 180: 449 456.
155. Nakayama, J.,, K. Yoshida,, H. Kobayashi,, A. Isogai,, D. B. Clewell,, and A. Suzuki. 1995. Cloning and characterization of a region of Enterococcus faecalis plasmid pPDl encoding pheromone inhibitor (ipd), pheromone sensitivity (traC), and pheromone shutdown (traB) genes. J. Bacteriol. 177: 5567 5573.
156. Nes, I. F.,, and V. G. H. Eijsink,. 1999. R egulation of group II peptide bacteriocin synthesis by quorum-sensing mechanisms, p. 175 192. In G. M. Dunny,, and S. C. Wïnans (éd.), Cell-Cell Signaling in Bacteria. ASM Press, Washington, D.C.
160. 156a. Netherwood, T.,, R. Bowden,, P. Harrison,, A. G. O'Donnell,, D. S. Parker,, and H. J. Gilbert 1999. Gene transfer in the gastrointestinal tract. Appl. Environ. Microbiol. 65: 5139 5141.
157. Norgren, M.,, and J. R. Scott 1991. The presence of conjugative transposon Tn916 in the recipient strain does not impede transfer of a second copy of the element. J. Bacteriol. 173: 319 324.
158. Oliver, D. R.,, B. L. Brown,, and D. B. Clewell. 1977. Characterization of plas-mids detennining hemolysin and bacteriocin production in Streptococcus faecalis 5952. J. Bactenol. 130: 948 950.
159. Oliver, D. R.,, B. L. Brown,, and D. B. Clewell. 1977. Analysis of plasmid de-oxyribonucleic acid in a cariogenic strain of Streptococcus faecalis: an approach to identifying genetic determinants on cryptic plasmids. J. Bacteriol. 130: 759 765.
160. Olmsted, S. B., G. M. Dunny, S. L. Erlandsen, and C. L. Wells. 1994. A plasmid-encoded surface protein on Enterococcus faecalis augments its internal-ization by cultured epithelial cells. J. Infect. Dis. 170: 1549 1556.
161. Olmsted, S. B.,, S. L. Erlandsen,, G. M. Dunny,, and C. L. Wells. 1993. High-resolution visualization by field emission scanning electron microscopy of Enterococcus faecalis surface proteins encoded by the pheromone-inducible conjugative plasmid pCFlO. J. Bacteriol. 175: 6229 6237.
162. Olmsted, S. B.,, S.-M. Kao,, L. J. van Putte,, J. C. Gallo,, and G. M. Dunny. 1991. Role of the pheromone-inducible surface protein Asc10 in mating aggregate formation and conjugal transfer of the Enterococcus faecalis plasmid pCF10. J. Bacteriol. 173: 7665 7672.
163. Pontius, L. T.,, and D. B. Clewell. 1991. A phase variation event that activates conjugation functions encoded by the Enterococcus faecalis plasmid pAD1. Plasmid 26: 172 185.
164. Pontius, L. T.,, and D. B. Clewell. 1992. Regulation of the pAD1-encoded pheromone response in Enterococcus faecalis: nucleotide sequence analysis of traA. J. Bacteriol. 174: 1821 1827.
165. Pontius, L. T.,, and D. B. Clewell. 1992. Conjugative transfer of Enterococcus faecalis plasmid pADl: nucleotide sequence and transcriptional fusion analysis of a region involved in positive regulation, J. Bactenol. 174: 3152 3160.
166. Poyart-Salmeron, C.,, P. Trieu-Cuot,, C. Carlier,, and P. Courvalin. 1989. Molecular characterization of two proteins involved in the excision of the conjugative transposon Tnl545: homologies with other site-specific recombinases. EMBO J. 8: 2425 2433.
167. Poyart-Salmeron, C.,, P. Trieu-Cuot,, C. Carlier,, and P. Courvalin. 1990. The integration-excision system of the conjugative transposon Tn 1545 is structurally and functionally related to those of lambdoid phages. Mol. Microbiol. 4: 1513 1521.
168. Prowedi, R.,, R. Manganelli,, and G. Pozzi. 1996. Characterization of conjugative transposon Tn 5251 of Streptococcus pneumoniae. FEMS Microbiol. Lett. 135: 231 236.
169. Rakita, R. M.,, N. N. Vanek,, K. Jacques-Palaz,, M. Mee,, M. M. Mariscalco,, G. M. Dunny,, M. Snuggs,, W. B. Van Winkle,, and S. I. Simon. 1999. Enterococcus faecalis bearing aggregation substance is resistant to killing by human neutrophils despite phagocytosis and neutrophil activation. Infect. Immun. 67: 6067 6075.
170. Rice, L. B. 1998. Tn916 family conjugative transposons and dissemination of antimicrobial resistance determinants. Antimicrob. Agents Chemother. 42: 1871 1877.
171. Rice, L. B.,, and L. L. Carias. 1998. Transfer of Tn5385, a composite, multire-sistance chromosomal element from Enterococcus faecalis. J. Bacteriol. 180: 714 721.
172. Ruhfel, R. E.,, D. A. Manias,, and G. M. Dunny. 1993. Cloning and characterization of a region of the Enterococcus faecalis conjugative plasmid, pCF10, encoding a sex pheromone-binding function, J. Bacteriol. 175: 5253 5259.
173. Salvers, A. A.,, N. B. Shoemaker,, A. M. Stevens,, and L. Y. Li. 1995. Conjugative transposons: an unusual and diverse set of integrated gene transfer elements. Microbiol. Rev. 59: 579 590.
174. Sannomiya, P.,, R. A. Craig,, D. B. Clewell,, A. Suzuki,, M. Fujino,, G. O. Till,, and W. A. Marasco. 1990. Characterization of a class of nonformylated Enterococcus faecalis-derived neutrophil chemotactic peptides: the sex pheromones. Proc. Natl. Acad. Set. USA 87: 66 70.
175. Schlievert, P. M.,, P. J. Gahr,, A. P. Assimacopoulos,, M. M. Dinges,, J. A. Stoehr,, J. W. Harmala,, H. Hirt,, and G. M. Dunny. 1998. Aggregation and binding substances enhance pathogenicity in rabbit models of Enterococcus faecalis endocarditis. Infect. Immun. 66: 218 223.
176. Schwarz, F. V.,, V. Perreten,, and M. Teuber. 2001. Sequence of the 50-kb conjugative multiresistance plasmid pRE25 from Enterococcus faecalis RE25. Plasmid 46: 170 187.
177. Scott, J. R.,, and G. Churchward. 1995. Conjugative transposition. Annu. Rev. Microbiol. 49: 367 397.
178. Scott, J. R.,, F. Bringel,, D. Marra,, G. Van Alstine,, and C. K. Rudy. 1994. Conjugative transposition of Tn926: preferred targets and evidence for conjugative transfer of a single strand and for a double-stranded circular intermediate. Mol. Microbiol. 11: 1099 1108.
179. Scott, J. R.,, A. Kirchman,, and M. G. Caparon. 1988. An intermediate in transposition of the conjugative transposon Tn916. Proc. Natl. Acad. Sci. USA 85: 4809 4813.
180. Senghas, E.,, J. M. Jones,, M. Yamamoto,, C. Gawron-Burke,, and D. B. Clewell. 1988. Genetic organization of the bacterial conjugative transposon Tn916. J. Bacteriol. 170: 245 249.
181. Showsh, S. A.,, and R. E. Andrews, Jr. 1992. Tetracycline enhances Tn916-mediated conjugal transfer. Plasmid 28: 213 224.
182. Showsh, S. A.,, and R. E. Andrews, Jr. 1996. Functional comparison of conju-gative transposons Tn916 and Tn925. Plasmid 35: 164 173.
183. Showsh, S. A.,, and R. E. Andrews, Jr. 1999. Analysis of the requirement for a pUBHO mob region during Tn916-dependent mobilization. Plasmid 41: 179 186.
184. Showsh, S. A.,, E. H. De Boever,, and D. B. Clewell. 2001. Vancomycin resistance plasmid in Enterococcus faecalis that encodes sensitivity to a sex phero-mone also produced by Staphylococcus aureus. Antimicrob. Agents Chemother. 45: 2177 2178.
185. Su, Y. A.,, and D. B. Clewell. 1993. Characterization of the left four kilobases of conjugative transposon Tn926. Determinants involved in excision. Plasmid 30: 234 250.
186. Su, Y. A.,, P. He,, and D. B. Clewell. 1992. Characterization of the tetQA) determinant of Tn916: evidence for regulation by transcription attenuation. Antimicrob. Agents Chemother. 36: 769 778.
187. Sussmuth, S. D.,, A. Muscholl-Silberhorn,, R. Wirth,, M. Susa,, R. Marre,, and E. Rozdzinski. 2000. Aggregation substance promotes adherence, phagocytosis, and intracellular survival of Enterococcus faecalis within human macrophages and suppresses respiratory burst. Infect. Immun. 68: 4900 4906.
188. Suzuki, A.,, M. Mori,, Y. Sakagami,, A. Isogai,, M. Fujino,, C. Kitada,, R. A. Craig,, and D. B. Clewell. 1984. Isolation and structure of bacterial sex pheromone, cPD1. Science 226: 849 850.
189. Swartley, J. S., C. F. McAllister, R. A. Hajjeh, D. W. Heinrich, and D. S. Stephens. 1993. Deletions of Tn926-like transposons are implicated in tetM-mediated resistance in pathogenic Neisseria. Mol. Microbiol. 10: 299 310.
190. Tanimoto, K.,, F. Y. An,, and D. B. Clewell. 1993. Characterization of the traC determinant of the Enterococcus faecalis hemolysin/bacteriocin plasmid pAD1. Binding of sex pheromone. J. Bacteriol. 175: 5260 5264.
191. Tanimoto, K.,, and D. B. Clewell. 1993. Regulation of the pAD1-encoded sex pheromone response in Enterococcus faecalis-. expression of the positive regulator TraE1. J. Bacteriol. 175: 1008 1018.
192. Tanimoto, K.,, H. Tomita,, and Y. Ike. 1996. The traA gene of the Enterococcus faecalis conjugative plasmid pPDl encodes a negative regulator for the pheromone response. Plasmid 36: 55 61.
193. Tomich, P. K.,, F. Y. An,, S. P. Damle,, and D. B. Clewell. 1979. Plasmid related transmissibility and multiple drug resistance in Streptococcus faecalis subspecies zymogenes strain DS16. Antimicrob. Agents Chemother. 15: 828 830.
194. Tomita, H.. Personal communication.
195. Tomita, H.,, and D. B. Clewell. 2000. A pAD1-encoded small RNA molecule, mD, negatively regulates Enterococcus faecalis pheromone response by enhancing transcription termination. J. Bacteriol. 182: 1062 1073.
196. Tomita, H.,, S. Fujimoto,, K. Tanimoto,, and Y. Ike. 1997. Cloning and genetic and sequence analyses of the bacteriocin 21 determinant encoded on the Enterococcus faecalis pheromone-responsive conjugative plasmid pPD1. J. Bacteriol. 179: 7843 7855.
197. Tomita, H.,, S. Fujimoto,, K. Tanimoto,, and Y. Ike. 1996. Cloning and genetic organization of the bacteriocin 31 determinant encoded on the Enterococcus faecalis pheromone-responsive conjugative plasmid pYI17. J. Bacteriol. 178: 3585 3593.
198. Torres, O. R.,, R. Z. Korman,, S. A. Zahler,, and G. M. Dunny. 1991. The conjugative transposon Tn925: enhancement of conjugal transfer by tetracycline in Enterococcus faecalis and mobilization of chromosomal genes in Bacillus subtilis and E. faecalis. Mol. Gen. Genet. 225: 395 400.
199. Trotter, K. M.,, and G. M. Dunny. 1990. Mutants of Enterococcus faecalis deficient as recipients in mating with donors carrying pheromone-inducible plasmids. Plasmid 24: 57 67.
200. Wanner, G.,, H. Formanek,, D. Galli,, and R. Wirth. 1989. Localization of aggregation substances of Enterococcus faecalis after induction by sex pheromones. An ultrastructural comparison using iirtmunolabelling, transmission and high resolution scanning electron microscopic techniques. Arch. Microbiol. 151: 491 497.
201. Waters, C. M.,, and G. M. Dunny. 2001. Analysis of functional domains of the Enterococcus faecalis pheromone-induced surface protein aggregation substance. J. Bacteriol. 183: 5659 5667.
202. Weaver, K. E.,, and D. B. Clewell. 1988. Regulation of the pADl sex pheromone response in Enterococcus faecalis: construction and characterization of lacZ tran-scriptional fusions in a key control region of the plasmid. J. Bacteriol. 170: 4343 4352.
203. Weaver, K. E.,, and D. B. Clewell. 1989. Construction of Enterococcus faecalis pADl miniplasmids: identification of a minimal pheromone response regulatory region and evaluation of a novel pheromone-dependent growth inhibition. Plasmid 22: 106 119.
204. Weaver, K. E.,, and D. B. Clewell. 1990. Regulation of the pADl sex pheromone response in Enterococcus faecalis: effects of host strain and traA, traB, and C region mutants on expression of an E region pheromone-inducible lacZ fusion. J. Bacteriol. 172: 2633 2641.
205. Weaver, K. E.,, and D. B. Clewell. 1991. Control of Enterococcus faecalis sex pheromone cAD1 elaboration: effects of culture aeration and pAD1 plasmid-encoded determinants. Plasmid 25: 177 189.
206. Weaver, K. E.,, D. B. Clewell,, and E Y. An. 1993. Identification, characterization, and nucleotide sequence of a region of Enterococcus faecalis pheromone-responsive plasmid pAD1 capable of autonomous replication, J. Bacteriol. 175: 1900 1909.
207. Weidlich, G.,, R. Wirth,, and D. Galli. 1992. Sex pheromone plasmid pADl-encoded surface exclusion protein of Enterococcus faecalis. Mol. Gen. Genet. 233: 161 168.
208. Wirth, R. 1994. The sex pheromone system of Enterococcus faecalis. More than just a plasmid-collection mechanism? Eur. J. Biochem. 222: 235 246.
209. Wirth, R. 2000. Sex pheromones and gene transfer in Enterococcus faecalis. Res. Microbiol. 151: 493 496.
210. Wirth, R.,, A. Friesenegger,, and T. Horaud. 1992. Identification of new sex pheromone plasmids in Enterococcus faecalis. Mol. Gen. Genet. 233: 157 160.
211. Wirth, R.,, and H. Marcinek,. 1995. In vivo gene transfer by Enterococcus faecalis, p. 51-54. In J. J. Ferretti,, M. S. Gilmore,, T. R. Klaenhammer,, and F. Brown (eds.), Genetics of Streptococci, Enterococci and Lactococci. Developmental and Biological Standards, vol. 85. Karger, Basel, Switzerland.
212. Wirth, R.,, A. Muscholl,, and G. Wanner. 1996. The role of pheromones in bacterial interaction. Trends Microbiol. 4: 96 103.
213. Wu, H. C., 1996. Biosynthesis of lipoproteins, p. 1005 1014. In F. C. Neidhardt,, R. Curtiss III,, J. L. Ingraham,, E. C. C. Lin,, K. B. Low,, B. Magasanik,, W. S. Reznikoff,, M. Riley,, M. Schaechter,, and H. E. Umbarger (éd.), Escherichia coli and Salmonella, 2nd ed. ASM Press , Washington, D.C.
214. Wu, K.,, F. Y. An,, and D. B. Clewell. 1999. Enterococcus faecalis pheromone-responding plasmid pADl gives rise to an aggregation (clumping) response when cells are exposed to subinhibitory concentrations of chloramphenicol, erythromycin, or tetracycline. Plasmid 41: 82 88.
215. Yagi, Y.,, R. E. Kessler,, J. H. Shaw,, D. E. Lopatin,, F. Y. An,, and D. B. Clewell. 1983. Plasmid content of Streptococcus faecalis strain 39-5 and identification of a pheromone (cPDl)-induced surface antigen, J. Gen. Microbiol. 129: 1207 1215.
216. Yarnell, W. S.,, and J. W. Roberts. 1999. Mechanism of intrinsic transcription termination and antitermination. Science 284: 611 615.

Tables

Generic image for table
Table 1

Plasmids that encode a pheromone response

Citation: Clewell D, Dunny G. 2002. Conjugation and Genetic Exchange in Enterococci, p 265-300. In Gilmore M, Clewell D, Courvalin P, Dunny G, Murray B, Rice L (ed), The Enterococci. ASM Press, Washington, DC. doi: 10.1128/9781555817923.ch7
Generic image for table
Table 2

Pheromone and inhibitor precursors

Citation: Clewell D, Dunny G. 2002. Conjugation and Genetic Exchange in Enterococci, p 265-300. In Gilmore M, Clewell D, Courvalin P, Dunny G, Murray B, Rice L (ed), The Enterococci. ASM Press, Washington, DC. doi: 10.1128/9781555817923.ch7

This is a required field
Please enter a valid email address
Please check the format of the address you have entered.
Approval was a Success
Invalid data
An Error Occurred
Approval was partially successful, following selected items could not be processed due to error