Genetics of Clostridium difficile Toxins

  • J. S. Moncrief
  • T. D. Wilkins
Part of the Current Topics in Microbiology and Immunology book series (CT MICROBIOLOGY, volume 250)


Up until the time it was implicated as the cause of pseudomembranous colitis (PMC), C. difficile was an almost unknown species of bacteria. The organism was first isolated from healthy newborn infants in 1935 by Hall and O’Toole, who named it Bacillus difficilis after the apparent difficulty they encountered in its isolation (Hall and O’Toole 1935). The organism produced a toxic culture filtrate which was lethal to animals upon injection. Perhaps due to the fact that the organism did not appear to cause disease, few studies followed its initial discovery. Over 40 years later, in 1977, C. difficile was implicated as the cause of a lethal colitis that resulted from treatment with antibiotics. The discovery resulted from the finding that antisera to C. sordellii neutralized toxic activity found in fecal filtrates from patients with antibiotic-associated colitis. Curiously, however, C. sordellü could not be isolated from the patients. C. difficile, on the other hand, had been isolated previously from many patients, but had been ignored since it was “nonpathogenic”. Further investigation showed that toxic activity in culture filtrates from C. difficile was neutralized by C. sordellii antisera. Thus the fortuitous cross-neutralizing activity of C. sordellii antisera led to the discovery of C.difficile as the cause of antibiotic-associated colitis.


Toxin Gene Lethal Toxin Alpha Toxin Active Site Motif Clostridium Difficile Toxin 
These keywords were added by machine and not by the authors. This process is experimental and the keywords may be updated as the learning algorithm improves.


Unable to display preview. Download preview PDF.

Unable to display preview. Download preview PDF.


  1. Aktories K (1997) Rho proteins: targets for bacterial toxins. Trends Microbiol 5: 282–288PubMedCrossRefGoogle Scholar
  2. Al-Barrak A, Embil J, Dyck B, Dickson K, Alfa M, Kabani A (1999) An outbreak of toxin A negative, toxin B positive Clostridium difficile-associated diarrhea in a Canadian tertiary-care hospital. Canada Communicable Dis Report 25: 65–69Google Scholar
  3. Alfa M, Lyerly D, Neville L, Moncrief S, Al-Barak A, Kabani A, Dyck B, Dickson K, Embil J (1999) Outbreak of toxin A(—), toxin B(+) Clostridium difficile difficile-associated diarrhea in a Canadian tertiary care hospital. Am Soc Microhiol Ann Meet Abstr, 99th.Google Scholar
  4. Arnon SS, Mills DC, Day PA, Henrickson RV, Sullivan NM, Wilkins TD (1984) Rapid death of infant rhesus monkeys injected with Clostridium difficile toxins A and B: physiologic and pathologic basis. J Pediatr 104: 34 40Google Scholar
  5. Ball DW, Van Tassel RL, Roberts MD, Hahn PE, Lyerly DM, Wilkins TD (1993) Purification and characterization of alpha-toxin produced by Clostridium novyi type A. Infect Immun 61: 2912–2918PubMedGoogle Scholar
  6. Barroso LA, Wang SZ, Phelps CJ, Johnson JI., Wilkins TI) (1990) Nucleotide sequence of the Clostridium difficile toxin B gene. Nucleic Acids Res 18: 4004PubMedCrossRefGoogle Scholar
  7. Barroso LA, Moncriel.IS. Lverly DM, Wilkins TD (1994) Mutagenesis of the Clostridium difficile toxin R gene and effect on cytotoxic activity. Microbial Pathog I6: 297–303CrossRefGoogle Scholar
  8. Bette P, Frcvert J, Mauler F, Suttorp N, Hahcrmann E (1989) Pharmacological and biochemical studies of the cytotoxicity of Clostridium nom type A alpha toxin. Infect Immun 57: 2507 2513Google Scholar
  9. Bette P, Oksche A, Mauler F. Iichel-Streiber Cv, Popoff M R, Hubermaui I: (1991) A comparative biochemical, pharmacological, and immunological study. of ChM Iridiunc nni.ri alpha - toxin. C. ut/uile toxin B and C. sordellii lethal toxin. Toxicon 29: 877–887Google Scholar
  10. Borriello SP, Wren BW, Hyde S, Seddon SV, Sibbons P, Krishna MM, Tabagch,ili S. Manck S, Price AB (1992) Molecular, immunological, and biological characterization of a toxin A-negative toxin B-positive strain of Clostridium difficile. Infect Immun 60: 4192–4199Google Scholar
  11. Borland V, Shao Y. Perna NT, Plunkett G, Sofia HJ, Blattner FR (1998) The complete DNA sequence and analysis of the large virulence plasmid of Clostridium difficile 0157:117. Nucleic Acids Res 20: 4196 4204Google Scholar
  12. Busch C, Ilofmann F, Selzer.1, Munro S, Jeckel I), Aktorics K (1998) A common motif of cukaryotic glycosyltrunsferases is essential for the enzyme activity of large clostridia’ toxins. J Biol Chem 273: 19566 19572Google Scholar
  13. Castagliuolo I, LaMont JT, Letourneau R, Kelly (’, O’Keane JC. Jailer A.’Lheoharides “LC. Polhoulakis C (1994) Neuronal involvement in the intestinal effects of Clostridium difficile toxin A and t ihrio cholera,enterotoxin in rat ileum. Gastroenterology 11)7:057–665Google Scholar
  14. Castagliuolo 1. Keates AC, Oie B. Kelly CP, Nikulasson S. Leeman SE, Polhoulakis C (1997) Increased substance P responses in dorsal root ganglia and intestinal macrophages during Clostridium difficile toxin A enteritis in rats. Proc Natl Acad Sci USA 94: 4788 4793Google Scholar
  15. Castagliulo I, Riegler M. Pasha A, Nikulasson, Lu B, Gerard C, Gerard NP, Polhoulakis (’ (1995) Neurokinin-1 (NK-I) receptor is required in Clostridium di/fiei/c-induced enteritis..I Clin Invest 101: 1547 1550Google Scholar
  16. Chaves-Olarte L:, Weidmann M. Eichel-Streibcr C. Thclestum M (1997) Toxins A and I3 from Clostridium difficile differ with respect to enzymatic potencies, cellular substrate specificities. and sur0nee binding to cultured cells..1 Clin Invest 1(10:1734–1741Google Scholar
  17. Ciesla WP, Bohak DA (1998) Clostridium difficile toxins A and B are cation-dependent Ill)P-Glucose hydrolases with differing catalytic act isities..I Biol Chem 273:16021–1602Google Scholar
  18. Cohen SH, Tang YJ, Hansen B, Silva J Jr (1998) Isolation of a toxin B-delienent mutant strain of Clostridium difficile in a case of recurrent C. difficile-associated diarrhea. (’tin Infect Dis 26: 410 412Google Scholar
  19. Depitre C, Delmer M, Avesani V, L’Haridon R, Roe’s A, Popoff M. Corthier G (1993) Serogroup E strains of Clostridium difficile produce toxin B but not toxin A..1 Med Microbiol 38: 434 441Google Scholar
  20. Dillon ST, Rubin L:J, Yakubovich M. Potholakis C. LaMont.IT, Feig LA, Gilbert RJ (1995) Invobement of Ras-Related Rho proteins in the mechanism of action of Clostridium difficile toxin A and toxin B. Infect Immun 63: 1421 1426Google Scholar
  21. Dove CH, Wang S-Z, Price SB, Phelps C.I, Lycrly DM, Wilkins TI). Johnson H. (199(1) Molecular characterization of the Clostridium difficile toxin A gene. Infect Immun 58: 480 488Google Scholar
  22. Dupray B, Sonenshein AI. (1998) Regulated transcription of Clostridium difficile toxin genes. Molecular Microbiology 27:107–12(1Google Scholar
  23. Ehrich M (1982) I3iochemical and pathological effects of Clostridium difficile toxins in mice Toxicon 20: 983–989Google Scholar
  24. Eichel-Streibcr CV, Suckau D. Wachter M, Hadding U (1988) Cloning and characterization of over- lapping DNA fragments of the toxin A gene of Clostridium difficile.I Gen Microbiol 135: 55 64Google Scholar
  25. Eichel-Streiber CV, Sauerborn M (1990) Clostridium difficile toxin A carries a C-terminal repetitive structure homologous to the carbohydrate binding region of streptococcal giscosyl-tnnsferases. (,ene 96: I (17–1 13Google Scholar
  26. Eichel-Streiber (’V, Laufenberg-Feldmann R, Sartingen S, Schilze J, Sauerborn M (1992a) Comparative sequence analysis of the Clostridium difficile toxins A and B. Mol Gen Genet 233: 260 268Google Scholar
  27. Eichel-Streiber CV, Sauerborn M, Kuramitsu HK (1992b) Evidence for,.c modular structure of the homologous repetitive C-terminal carbohydrate-binding sites of Clostridium difficile toxins and Streptococcus unarms glycosyltranslerases..I Bacteriol 174:671)7–6710Google Scholar
  28. Fichel-Streiber CV (1995) Molecular biology of the Clostridium difficile. In: Sebald M (ed) Genetics and molecular biology of the anaerobic bacteria. Springer-Verlag. New York pp 264 289Google Scholar
  29. Eichel-Streiber CV, Roquet P. Sauerborn M (1996) Large clostridia’ cytotoxins • Innnily of glucosyl-transferases modifying small GTP-binding proteins. Trends Microbiol 2: 375 382Google Scholar
  30. Eklund MW, Poysky FT, Meyers JA, Pelroy GA (1974) Interspecies conversion of Clostridium hontlirmum type C to Clostridium noryi type A by bacteriophage. Science 186: 456–458PubMedCrossRefGoogle Scholar
  31. Eklund MW, Poysky FT, Peterson ME, Meyers JA (1976) Relationship of bacteriophages to alpha toxin production in Clostridium nom types A and B. Infect Immun 14: 793–803PubMedGoogle Scholar
  32. Fiorentini C, Malorni W, Paradisi S, Giuliano M, Mastrantonio P, Donelli G (1990) Interaction of Clostridium difficile toxin A with cultured cells: cytoskeletal changes and nuclear polarization. infect Immun 58: 2329–2336Google Scholar
  33. Florin I, Theleslam M (1983) internalization of Clostridium difficile cytotoxin into cultured human lung fibroblasts. Biochim Biophys Acta 763: 383–392Google Scholar
  34. Frey S, Wilkins TD (1992) Localization of two epitopes recognized by monoclonal antibody PC’G-4 on Clostridium difficile toxin A. Infect immun 60: 2488–2492PubMedGoogle Scholar
  35. Genth II, Hofmann F. Selzer J, Rex G, Aktories K, Just I (1996) Difference in protein substrate specificity between hemorrhagic toxin and lethal toxin from Clostridium sordellii. Biochem Biophys Res Common 229: 370–374Google Scholar
  36. Green GA, Sehne V, Montcil (1995) Cloning and characterization of the cytotoxin L-encoding gene of Clostridium sordellii: homology with Clostridium difficile toxin B. Gene 161: 57–61Google Scholar
  37. Groisman EA, Ochman H (1996) Pathogenicity islands: bacterial evolution in quantum leaps. Cell 87: 791–794PubMedCrossRefGoogle Scholar
  38. Hacker J. Blum-Oehler G, Muhldorfer, Tschape (1997) Pathogenicity islands of virulent bacteria: structure, function and impact on microbial evolution. Mol Microbiol 23: 1089–1097Google Scholar
  39. Hagen 1K, Hazes B, Raflo R, de Sa D, Tabak LA (1999) Structure and function of the UDP-Nacetyl-Dgalactosamine: polypeptide N-acetylgalactosaminyltransferase. Essential residues lie in a predicted active site cleft resembling a lactose repressor fold. J Biol Cheni 274: 6797–6803Google Scholar
  40. Hall.1, O’Toole E (1935) Intestinal flora in newborn infants with description of a new pathogenic organism, Bacillus difficili.s. Am J Dis Child 135: 390–402Google Scholar
  41. Hall A (1998) Rho GTPases and the actin cytoskeleton. Science 279: 509–514PubMedCrossRefGoogle Scholar
  42. Hammond GA, Johnson JL (1995) The toxigenic element of Clostridium difficile strain 10463. Microb Pathog 19: 203–213PubMedCrossRefGoogle Scholar
  43. Hammond GA, Lyerly DM, Johnson JL (1996) Transcriptional analysis of the toxigenic element or Clostridium difficile. Microb Pathog 22: 143–154CrossRefGoogle Scholar
  44. Hecht G, Pothoulakis C, LaMont JT, Madara JL (1988) Clostridium difficile toxin A perturbs cytoskeletal structure and junction permeability in cultured human epithelial cells. J Clin Invest 82: 1516–1524Google Scholar
  45. Henriques B, Florin I, Thelestam M (1987) Cellular internalization of C7o.stridium difficile toxin A. Microb Pathog 2: 455–463PubMedCrossRefGoogle Scholar
  46. Hippensteil S, Tanners-Otto S, Vollrath N, Krull M, Just I, Aktories K, von Eichel-Streiber C, Suttrop N (1997) Glucosylation of the small GTP-binding Rho proteins disrupts endothelial barrier function. Am J Physiol 272:L38 L43Google Scholar
  47. Hofmann F, Haberman’) F. von Eichel-Streiber C (1995) Sequencing and analysis of the gene encoding the alpha-toxin of Clostridium noryi proves its homology to toxins A and B of Clostridium difficile. Mol Gen Genet 247: 670–679PubMedCrossRefGoogle Scholar
  48. Hofmann F, Rex G, Aktories K, Just I (1996) The ras-related protein Ral is monoglucosylated by Clostridium.sordrllii lethal toxin. Biochem Biophys Res Commun 227: 77–81PubMedCrossRefGoogle Scholar
  49. Hofmann F, Busch C, Prepens U, Just 1, Aktories K (1997) Localization of the glucosyltransferase activity of Clostridium difficile toxin B to the N-terminal part of the holotoxin..1 Blot Chem 272: 1 1074 11078Google Scholar
  50. Hofmann F, Busch C, Aktories K (1998) Chimeric clostridia) cytotoxins: identification of the N-terminal region involved in protein substrate recognition. Infect immun 66: 1076–1081PubMedGoogle Scholar
  51. Hundsberger T, Braun V, Weidmann M, Leukel P, Sauerborn M, Eichel-Streiber CV (1997) Transcription analysis of the genes tcd,4-E of the pathogenicity locus of Clostridium difficile. Fur J Biochem 244: 735–742Google Scholar
  52. Johnson JL, Phelps (’J, Barroso LA, Roberts MD, Lyerly DM, Wilkins TD (1990) Cloning and expression of the toxin B gene of Clostridium difficile. Curr Microbiol 20: 397–401Google Scholar
  53. Just I, Fritz G, Aktories K, Giry M, Popoff MR, Boquet P, Hegenbarth S, Eichel-Streiber CV (1994) Clostridium difficile toxin B acts on the GTP-binding protein Rho. J Biol Chem 269: 10706–10712Google Scholar
  54. Just I, Selzer J, Eichel-Streiber Cv, Aktories K (1995a) The low molecular mass GTP-binding protein Rho is affected by toxin A from Clostridium difficile. J Clin Invest 95: 1026–1031PubMedCrossRefGoogle Scholar
  55. Just I, Selzer J, Wilm M, Eichel Streiber Cv, Mann M, Aktories K (1995h) Glucosylation of Rho proteins by Clostridium difficile toxin B. Nature 375: 500–503PubMedCrossRefGoogle Scholar
  56. Just I, Wilm M, Selzer J, Rex G, Eichel Streiber Cv, Mann M, Aktories K (1995c) “[he enterotoxin from Clostridium diJ/mile (ToxA) monoglucosylates the Rho proteins..I Biol (’hem 270: 13932 13939Google Scholar
  57. Just I, Selzer J, Hofmann F, Green GA, Aktories K (1996) Inactivation of Ras by Clostridium sorrlellii lethal toxin-catalyzed glucosylation. J Biol Chem 271: 10149 I0153Google Scholar
  58. Kato H, Kato N, Wantabc K, Iwai N, Nakamura IL Yamamoto T, Suzuki K, Kim S-M. Chong Y. Wasito EB (1998) Identification of toxin A-negative, toxin B-positive Clostridium eli_f/icile by PCR.,1 Clin Microbiol 36: 2178–2182Google Scholar
  59. Krivan HC, Clark GF, Smith DF,Wilkins TI) (1986) Cell surface binding site for Clostridium di//irilr enterotoxin: evidence for a glycoconjugate containing the sequence Gal5(1–3Galßl-4(ì1eNAc. Infect immun 53: 573 581Google Scholar
  60. Libby JM, Jortner BS, Wilkins TD (1982) Effects of the two toxins of clostridium dì%flri/e in antibiotic-associated cecitis in hamsters. Infect Immun 36: 822–829PubMedGoogle Scholar
  61. Lima AAM, Lyerly I)M, Wilkins TD, lines DJ, Guerrant RL (1988) Effects of Clostridium difficile toxins A and B in rabbit small and large intestine in vivo and on cultured cells in vitro. missi Immun 56: 582–588Google Scholar
  62. Lyerly DM, Lockwood DE, Richardson SH, Wilkins TI) (1982) Biological activities of toxins A and B of Clostridium difficile. Infect Immun 35:1 147–1 150Google Scholar
  63. Lyerly DM, Sullivan NM, Wilkins TD (1983) Enzyme-linked immunosorbcnl assay Ior Clostridium difficile toxin A..1 Clin Microbiol 17: 72–78Google Scholar
  64. Lyerly DM, Saum KE, MacDonald DK, Wilkins TI) (1985) Effects of Clostridium dif/ici/e toxins given intragastrically to animals. Infect Immun 47: 349 352Google Scholar
  65. Lyerly DM, Roberts MD, Phelps (’J, Wilkins TI) (1986) Purification and properties of toxins A and B of Clostridium d/me FEMS Microbiol Lett 33: 31 35Google Scholar
  66. Lyerly DM, Barroso LA, Wilkins TI), Depitre C, Corthier G (1992) Characterization of u toxin A-negative, toxin B-positive strain of Clostridium difficile. Infect Immun 60: 4633 4639Google Scholar
  67. Lyerly DM. Wilkins TD (1995) Clostridium dif/lei/e. In: Blaser M.I, Smith PD. Ravdin JI, Greenberg I IB, (inerrant RL (eds) Infections of the Gastrointestinal Tract. Raven Press, New York, pp 867–891Google Scholar
  68. Makay DJG, Hall A (1998) Rho GTPases. J Biol Chem 273: 20685–20688CrossRefGoogle Scholar
  69. Manyth CR, Maggio JE, Mantyth PW, Vigna SR, Pappas TN (1996a) Increased substance l’ receptor expression by blood vessels and lymphoid tissue aggregates in Clostridium r/i//ici/e-induced pseudo-membranous colitis. Dig Dis Sei 41: 614–620CrossRefGoogle Scholar
  70. Mantyh CR, Pappas TN, Lapp JA, Washington MK, Neville LM, Ghilardi JR, Rogers SD. Manyth PW. Vigna SR (1996b) Substance P activation of enteric neurons in response to intraluminal Clostridium difficile toxin A in the rat ileum. Gastroenterology 111: 1272 1280Google Scholar
  71. Martinez RD, Wilkins TD (1988) Purification and characterization of Clostridium surr/el/ii hemorrhagic toxin and cross-reactivity with Clostridium difficile toxin A (enterotoxin). Infect Immun 56: 1215 1221Google Scholar
  72. Martinez RD, Wilkins TD (1992) Comparison of Clostridium.sortie!/ü toxins If I“ and I.T with toxins A and B of C. dif/icile..1 Med Microbiol 36: 30–36Google Scholar
  73. Marvaud JC, Eisen Il, Binz T, Nieman II, Popoff MR (1998) TetR is a positive regulator of the tetanus toxin gene in Clostridium tetaai and is homologous to bot R. Infect Immun 66: 5698–5702PubMedGoogle Scholar
  74. Marvaud JC, (iihert M, Inoue K, Fujinaga Y, Ogunra K, Popoff MR (1998) botR“A is a positive regulator of the hotulinum neurotoxin and associated non-toxin protein genes in Clostridium hotu/iumn A. Mol Microbiol 29: 1009–1018Google Scholar
  75. Missiakas I), Raina S (1998) The extracytoplasmic function factors: role and regulation. Mol Microbiol 28: 1059–1066PubMedCrossRefGoogle Scholar
  76. Mitchell J, Laughon BE, Lin S (1987) Biochemical studies on the clfect of Clostridium difficile toxin B on actin in vivo and in vitro. Infect Immun 55:161(1–1615Google Scholar
  77. Moncrief JS, Barroso LA, Wilkins Ti) (1997a) Positive regulation of C7nstriditun di//iei/e toxins. Infect Immun 65: 1105–1108PubMedGoogle Scholar
  78. Moncrief JS, Lyerly DM, Wilkins TD (1997h) Molecular biology of the Clostridium difficile toxins. In: Rood JI, Songer G, McClane B, Tithall R (eds) Molecular Genetics and Pathogenesis of the Clostridia. Academic Press, London, pp 369–392Google Scholar
  79. Moncrief JS, Duncan AJ, Wright RL, Barroso LA, Wilkins TD (1998) Molecular characterization of the fragilysin pathogenicity islet of enterotoxigenic Bacteroides /ragi/is. Infect Immun 66: 1735 1739Google Scholar
  80. Moncrief JS, Neville LM, Lyerly DM (1999) Molecular characterization of toxin A-negativetoxin B-positive strains of Clostridium difficile. Am Soc Microbiol, Ahstr Ann Meet. 99thGoogle Scholar
  81. Muldrow LL. Iheanu GC, Lee NI, Bose NK, Johnson.1 (1987) Molecular cloning of Clostridium (Wile toxin A gene fragment in lambdas gt1 L FEBS Lett 213: 249 253Google Scholar
  82. Mullany P, Wilks M, Lamb 1, Clayton C, Wren B, Tobaqchali S (1990) Genetic analysis of a tetracycline resistance element from Clostridium difficile and its conjugal transfer to and from Bacillus subtilis. J Gen Microbiol 136:1343 -I349Google Scholar
  83. Mullany P, Wilks M, Tobaqchali S (1991) Transfer of Tn9/6 and Tn9/6AE into Clostridium difficile: demonstration of a hot spot for these elements in the C. difficile genome. FEMS Microbiol Lett 79: 191–194Google Scholar
  84. Mullany P, Wilks M, Puckey L, Tabagchali S (1994) Gene cloning in Clostridium difficile using Tn9/6 as a shuttle conjugative transposon. Plasmid 31: 320–323PubMedCrossRefGoogle Scholar
  85. Ottlinger ME, Lin S (1988) Clostridium difficile toxin B induces reorganization of actin, vinculin and talin in cultured cells. Exp Cell Res 174: 215–229Google Scholar
  86. Phelps CJ, Lyerly DM, Johnson JL, Wilkins Ti) (1991) Construction and expression of the complete Clostridium difficile toxin A gene in Escherichia coli. Infect immun 59:I50N53Google Scholar
  87. Popoff MR (1986) Purification and characterization of Clostridium sordel/ii lethal toxin and cross-reactivity with Clostridium difficilr cytotoxin. Infect immun 55: 35–43Google Scholar
  88. Popoff MR, Chaves-Olarte E, Lemichez E, von Eichel-Streiber C, Thelstam M, Chardin P, Cusssac D, Antony B, Chavier P, Flatau G, Giry M, de Gunzburg J, Boquet P (1996) Ras, Rap, and Rae small GTP-binding proteins are targets for Clostridium sordellii lethal toxin glucosylation. J Biol Chem 271: 10217–10224PubMedCrossRefGoogle Scholar
  89. Pothoulakis C, C’astigiuolo I, LaMont JT, Jaflèr A, O’Keane JC, Snider RM, Leeman SE (1994) CP96,345, a substance P antagonist inhibits rat intestinal responses to Clostridium difficile toxin A but not cholera toxin. Proc Natl Acad Sci USA 91: 947–951PubMedCrossRefGoogle Scholar
  90. Pothoulakis C, Gilbert RJ, Cladaras C, Castagliuolo i, Semenza G, Hitti Y, Moncrief JS, Linevsky J, Kelly CP, Nikulasson S, Desai HP, Wilkins TD, LaMont JT (1996) Rabbit sucrase-isomaltase contains a functional intestinal receptor for Clostridium difficile toxin A. J Clin Invest 98: 641 649Google Scholar
  91. Pothoulakis C, Castagliuolo I, Leeman SE, Wang CC, Li H, Hofmann BJ, Mezey E (1998) Substance P receptor expression in intestinal epithelium in Clostridium difficile toxin A enteritis in rats. Am J Physiol 275: G68–675PubMedGoogle Scholar
  92. Price SB, Phelps CJ, Wilkins TD, Johnson JL (1987) Cloning of the carbohydrate binding portion of the toxin A gene of Clostridium diffcile. Curer Microbiol 16: 55–60CrossRefGoogle Scholar
  93. Riegler M, Sedivy R, Pothoulakis C, Hamilton G, Johannes Z, Bischof G, Costentini E, Wolfgang F, Schiessel, LaMont JT, Wenzl E (1995) Clostridium difficile toxin B is more potent than toxin A in damaging human colonic epithelium in vitro. J Clin Invest 95: 2004–2011Google Scholar
  94. Rupkin M, Braun V, Soehn F, Jane M, Hofstetter M, Laufenberg-Feldmann R, von Eichel-Streiber C (1997) Characterization of polymorphisms in the toxin A and B genes of Clostridium difficile. FEMS Microbiol Lett 148: 197 202Google Scholar
  95. Rupkin M, Avesani V, Jane M, Eichel-Streiber Cv, Delmee M (1998) A novel toxinotyping scheme and correlation of toxinotypes with serogroups of Clostridium difficile isolates. J Clin Microbiol 36: 2240–2247Google Scholar
  96. Sehr P, Joseph G, Genth H, Just i, Pick E, Aktories K (1998) Glucosylation and ADP ribosylation of rho proteins: e0ects on nucleotide binding, GTPase activity, and effector coupling. Biochemistry 37: 5296–5304Google Scholar
  97. Selzer J, Hofmann F, Rex G, Wilm M, Mann M, Just 1, Aktories K (1996) Clostridium nervi alpha-toxin-catalyzed incorporation of GIcNAc into Rho subfamily proteins. J Biol Chem 271: 25173–25177Google Scholar
  98. Smith JA, Cooke DL, Hyde S, Borrielo SP, Long (1997) Clostridium diflicle binding to human epithelial cells. J Med Microbiol 46: 953–958Google Scholar
  99. Soehn F, Wagenknecht-Wiesner A, Leukel P, Kohl M, Weidmann M, von Eichel-Streiber C, Braun V (1998) Genetic rearrangements in the pathogenicity locus of Clostridium difficile strain 8864 - implications for the transcription, expression and enzymatic activity of toxin A and B. Mol Gen Genet 258: 222 2. 32Google Scholar
  100. Song KP, Faust C (1998) Molecular analysis of the promoter region of the Clostridium difficile toxin B gene that is functional in Escherichia roll. J Med Microbiol 47: 309–316PubMedCrossRefGoogle Scholar
  101. Sterne M, Wentzel LM (1950) A new method for the large scale production of high titre botulinum Formal-toxoid types C and D. J Immunol 65: 175–183PubMedGoogle Scholar
  102. Thelestam M, Bronnegard M (1980) Interaction of cytopathogenic toxin from Clostridium difficile with cells in tissue culture. Scand.I Infect Dis 22: 16 29Google Scholar
  103. Torres,1F (1991) Purification and characterization of toxin B from a strain of Clostridium difficile that does not produce toxin A. J Med Microbiol 35: 40–44PubMedCrossRefGoogle Scholar
  104. Tucker KD, Carrig PE, Wilkins TI) (1990) Toxin A of Clostridium diide is a potent cytotoxin. J Clin Microbiol 28: 869 871Google Scholar
  105. Tucker K, Wilkins TD (1991) Toxin A of C7osnidium di//ìcle hinds to the human carbohydrate antigens I, X, and Y. Infect Immun 59: 73–78Google Scholar
  106. Wagenknecht-Wiesner A, Weidmann M, Braun V, Leukel P, Moos M. on I ichel-Streiher (’v (1997) Delineation of the catalytic domain of the C/osiridirnn di%flci/e toxin B-10463 to an enigmatically active N-terminal 467 amino acid fragment. FEMS Microbiol Felt 152: 109 116Google Scholar
  107. Wren BW, Clayton CL, Mullany PP, Tabagchali S (1989) Molecular cloning and expression of (/ostridiunr difficile toxin A in Escherichiu soli K 12. FIBS Lett 225: 82 86Google Scholar
  108. Yamakawa K, Karasava T, Ikoma S, Nakamura S (1996) Enhancement of Clostridium difficile toxin production in biotin-limited conditions..1 Med Microbiol 44: 111 114Google Scholar

Copyright information

© Springer-Verlag Berlin Heidelberg 2000

Authors and Affiliations

  • J. S. Moncrief
    • 1
    • 2
  • T. D. Wilkins
    • 1
    • 2
  1. 1.Fralin Biotechnology CentreVirginia Polytechnic Institute and State UniversityBlacksburgUSA
  2. 2.TechLab Inc.BlacksburgUSA

Personalised recommendations