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. 1996 Mar;178(6):1720–1730. doi: 10.1128/jb.178.6.1720-1730.1996

Erwinia amylovora secretes harpin via a type III pathway and contains a homolog of yopN of Yersinia spp.

A J Bogdanove 1, Z M Wei 1, L Zhao 1, S V Beer 1
PMCID: PMC177859  PMID: 8626302

Abstract

Type III secretion functions in flagellar biosynthesis and in export of virulence factors from several animal pathogens, and for plant pathogens, it has been shown to be involved in the export of elicitors of the hypersensitive reaction. Typified by the Yop delivery system of Yersinia spp., type III secretion is sec independent and requires multiple components. Sequence analysis of an 11.5-kb region of the hrp gene cluster of Erwinia amylovora containing hrpI, a previously characterized type III gene, revealed a group of eight or more type III genes corresponding to the virB or lcrB (yscN-to-yscU) locus of Yersinia spp. A homolog of another Yop secretion gene, yscD, was found between hrpI and this group downstream. Immediately upstream of hrpI, a homolog of yopN was discovered. yopN is a putative sensor involved in host-cell-contact-triggered expression and transfer of protein, e.g., YopE, to the host cytoplasm. In-frame deletion mutagenesis of one of the type III genes, designated hrcT, was nonpolar and resulted in a Hrp- strain that produced but did not secrete harpin, an elicitor of the hypersensitive reaction that is also required for pathogenesis. Cladistic analysis of the HrpI (herein renamed HrcV) or LcrD protein family revealed two distinct groups for plant pathogens. The Yersinia protein grouped more closely with the plant pathogen homologs than with homologs from other animal pathogens; flagellar biosynthesis proteins grouped distinctly. A possible evolutionary history of type III secretion is presented, and the potential significance of the similarity between the harpin and Yop export systems is discussed, particularly with respect to a potential role for the YopN homolog in pathogenesis of plants.

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Selected References

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  1. Albertini A. M., Caramori T., Crabb W. D., Scoffone F., Galizzi A. The flaA locus of Bacillus subtilis is part of a large operon coding for flagellar structures, motility functions, and an ATPase-like polypeptide. J Bacteriol. 1991 Jun;173(11):3573–3579. doi: 10.1128/jb.173.11.3573-3579.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  2. Allaoui A., Sansonetti P. J., Parsot C. MxiD, an outer membrane protein necessary for the secretion of the Shigella flexneri lpa invasins. Mol Microbiol. 1993 Jan;7(1):59–68. doi: 10.1111/j.1365-2958.1993.tb01097.x. [DOI] [PubMed] [Google Scholar]
  3. Allaoui A., Sansonetti P. J., Parsot C. MxiJ, a lipoprotein involved in secretion of Shigella Ipa invasins, is homologous to YscJ, a secretion factor of the Yersinia Yop proteins. J Bacteriol. 1992 Dec;174(23):7661–7669. doi: 10.1128/jb.174.23.7661-7669.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  4. Allaoui A., Woestyn S., Sluiters C., Cornelis G. R. YscU, a Yersinia enterocolitica inner membrane protein involved in Yop secretion. J Bacteriol. 1994 Aug;176(15):4534–4542. doi: 10.1128/jb.176.15.4534-4542.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Altschul S. F., Lipman D. J. Protein database searches for multiple alignments. Proc Natl Acad Sci U S A. 1990 Jul;87(14):5509–5513. doi: 10.1073/pnas.87.14.5509. [DOI] [PMC free article] [PubMed] [Google Scholar]
  6. Andrews G. P., Maurelli A. T. mxiA of Shigella flexneri 2a, which facilitates export of invasion plasmid antigens, encodes a homolog of the low-calcium-response protein, LcrD, of Yersinia pestis. Infect Immun. 1992 Aug;60(8):3287–3295. doi: 10.1128/iai.60.8.3287-3295.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  7. Arlat M., Gough C. L., Barber C. E., Boucher C., Daniels M. J. Xanthomonas campestris contains a cluster of hrp genes related to the larger hrp cluster of Pseudomonas solanacearum. Mol Plant Microbe Interact. 1991 Nov-Dec;4(6):593–601. doi: 10.1094/mpmi-4-593. [DOI] [PubMed] [Google Scholar]
  8. Bergman T., Erickson K., Galyov E., Persson C., Wolf-Watz H. The lcrB (yscN/U) gene cluster of Yersinia pseudotuberculosis is involved in Yop secretion and shows high homology to the spa gene clusters of Shigella flexneri and Salmonella typhimurium. J Bacteriol. 1994 May;176(9):2619–2626. doi: 10.1128/jb.176.9.2619-2626.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Bischoff D. S., Ordal G. W. Identification and characterization of FliY, a novel component of the Bacillus subtilis flagellar switch complex. Mol Microbiol. 1992 Sep;6(18):2715–2723. doi: 10.1111/j.1365-2958.1992.tb01448.x. [DOI] [PubMed] [Google Scholar]
  10. Bischoff D. S., Weinreich M. D., Ordal G. W. Nucleotide sequences of Bacillus subtilis flagellar biosynthetic genes fliP and fliQ and identification of a novel flagellar gene, fliZ. J Bacteriol. 1992 Jun;174(12):4017–4025. doi: 10.1128/jb.174.12.4017-4025.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Carpenter P. B., Ordal G. W. Bacillus subtilis FlhA: a flagellar protein related to a new family of signal-transducing receptors. Mol Microbiol. 1993 Mar;7(5):735–743. doi: 10.1111/j.1365-2958.1993.tb01164.x. [DOI] [PubMed] [Google Scholar]
  12. Carpenter P. B., Zuberi A. R., Ordal G. W. Bacillus subtilis flagellar proteins FliP, FliQ, FliR and FlhB are related to Shigella flexneri virulence factors. Gene. 1993 Dec 31;137(2):243–245. doi: 10.1016/0378-1119(93)90014-t. [DOI] [PubMed] [Google Scholar]
  13. Devereux J., Haeberli P., Smithies O. A comprehensive set of sequence analysis programs for the VAX. Nucleic Acids Res. 1984 Jan 11;12(1 Pt 1):387–395. doi: 10.1093/nar/12.1part1.387. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Fenselau S., Balbo I., Bonas U. Determinants of pathogenicity in Xanthomonas campestris pv. vesicatoria are related to proteins involved in secretion in bacterial pathogens of animals. Mol Plant Microbe Interact. 1992 Sep-Oct;5(5):390–396. doi: 10.1094/mpmi-5-390. [DOI] [PubMed] [Google Scholar]
  15. Fields K. A., Plano G. V., Straley S. C. A low-Ca2+ response (LCR) secretion (ysc) locus lies within the lcrB region of the LCR plasmid in Yersinia pestis. J Bacteriol. 1994 Feb;176(3):569–579. doi: 10.1128/jb.176.3.569-579.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  16. Forsberg A., Rosqvist R., Wolf-Watz H. Regulation and polarized transfer of the Yersinia outer proteins (Yops) involved in antiphagocytosis. Trends Microbiol. 1994 Jan;2(1):14–19. doi: 10.1016/0966-842x(94)90339-5. [DOI] [PubMed] [Google Scholar]
  17. Forsberg A., Viitanen A. M., Skurnik M., Wolf-Watz H. The surface-located YopN protein is involved in calcium signal transduction in Yersinia pseudotuberculosis. Mol Microbiol. 1991 Apr;5(4):977–986. doi: 10.1111/j.1365-2958.1991.tb00773.x. [DOI] [PubMed] [Google Scholar]
  18. Francis N. R., Sosinsky G. E., Thomas D., DeRosier D. J. Isolation, characterization and structure of bacterial flagellar motors containing the switch complex. J Mol Biol. 1994 Jan 28;235(4):1261–1270. doi: 10.1006/jmbi.1994.1079. [DOI] [PubMed] [Google Scholar]
  19. Galán J. E., Ginocchio C., Costeas P. Molecular and functional characterization of the Salmonella invasion gene invA: homology of InvA to members of a new protein family. J Bacteriol. 1992 Jul;174(13):4338–4349. doi: 10.1128/jb.174.13.4338-4349.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  20. Ginocchio C. C., Olmsted S. B., Wells C. L., Galán J. E. Contact with epithelial cells induces the formation of surface appendages on Salmonella typhimurium. Cell. 1994 Feb 25;76(4):717–724. doi: 10.1016/0092-8674(94)90510-x. [DOI] [PubMed] [Google Scholar]
  21. Gough C. L., Genin S., Lopes V., Boucher C. A. Homology between the HrpO protein of Pseudomonas solanacearum and bacterial proteins implicated in a signal peptide-independent secretion mechanism. Mol Gen Genet. 1993 Jun;239(3):378–392. doi: 10.1007/BF00276936. [DOI] [PubMed] [Google Scholar]
  22. Gough C. L., Genin S., Zischek C., Boucher C. A. hrp genes of Pseudomonas solanacearum are homologous to pathogenicity determinants of animal pathogenic bacteria and are conserved among plant pathogenic bacteria. Mol Plant Microbe Interact. 1992 Sep-Oct;5(5):384–389. doi: 10.1094/mpmi-5-384. [DOI] [PubMed] [Google Scholar]
  23. Groisman E. A., Ochman H. Cognate gene clusters govern invasion of host epithelial cells by Salmonella typhimurium and Shigella flexneri. EMBO J. 1993 Oct;12(10):3779–3787. doi: 10.1002/j.1460-2075.1993.tb06056.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  24. Haddix P. L., Straley S. C. Structure and regulation of the Yersinia pestis yscBCDEF operon. J Bacteriol. 1992 Jul;174(14):4820–4828. doi: 10.1128/jb.174.14.4820-4828.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  25. He S. Y., Huang H. C., Collmer A. Pseudomonas syringae pv. syringae harpinPss: a protein that is secreted via the Hrp pathway and elicits the hypersensitive response in plants. Cell. 1993 Jul 2;73(7):1255–1266. doi: 10.1016/0092-8674(93)90354-s. [DOI] [PubMed] [Google Scholar]
  26. Hsia R. C., Small P. L., Bavoil P. M. Characterization of virulence genes of enteroinvasive Escherichia coli by TnphoA mutagenesis: identification of invX, a gene required for entry into HEp-2 cells. J Bacteriol. 1993 Aug;175(15):4817–4823. doi: 10.1128/jb.175.15.4817-4823.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  27. Huang H. C., He S. Y., Bauer D. W., Collmer A. The Pseudomonas syringae pv. syringae 61 hrpH product, an envelope protein required for elicitation of the hypersensitive response in plants. J Bacteriol. 1992 Nov;174(21):6878–6885. doi: 10.1128/jb.174.21.6878-6885.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  28. Huang H. C., Lin R. H., Chang C. J., Collmer A., Deng W. L. The complete hrp gene cluster of Pseudomonas syringae pv. syringae 61 includes two blocks of genes required for harpinPss secretion that are arranged colinearly with Yersinia ysc homologs. Mol Plant Microbe Interact. 1995 Sep-Oct;8(5):733–746. doi: 10.1094/mpmi-8-0733. [DOI] [PubMed] [Google Scholar]
  29. Huang H. C., Xiao Y., Lin R. H., Lu Y., Hutcheson S. W., Collmer A. Characterization of the Pseudomonas syringae pv. syringae 61 hrpJ and hrpI genes: homology of HrpI to a superfamily of proteins associated with protein translocation. Mol Plant Microbe Interact. 1993 Jul-Aug;6(4):515–520. doi: 10.1094/mpmi-6-515. [DOI] [PubMed] [Google Scholar]
  30. Huynh T. V., Dahlbeck D., Staskawicz B. J. Bacterial blight of soybean: regulation of a pathogen gene determining host cultivar specificity. Science. 1989 Sep 22;245(4924):1374–1377. doi: 10.1126/science.2781284. [DOI] [PubMed] [Google Scholar]
  31. Hwang I., Lim S. M., Shaw P. D. Cloning and characterization of pathogenicity genes from Xanthomonas campestris pv. glycines. J Bacteriol. 1992 Mar;174(6):1923–1931. doi: 10.1128/jb.174.6.1923-1931.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  32. Innes R. W., Bent A. F., Kunkel B. N., Bisgrove S. R., Staskawicz B. J. Molecular analysis of avirulence gene avrRpt2 and identification of a putative regulatory sequence common to all known Pseudomonas syringae avirulence genes. J Bacteriol. 1993 Aug;175(15):4859–4869. doi: 10.1128/jb.175.15.4859-4869.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  33. Jones C. J., Homma M., Macnab R. M. L-, P-, and M-ring proteins of the flagellar basal body of Salmonella typhimurium: gene sequences and deduced protein sequences. J Bacteriol. 1989 Jul;171(7):3890–3900. doi: 10.1128/jb.171.7.3890-3900.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  34. Kaniga K., Bossio J. C., Galán J. E. The Salmonella typhimurium invasion genes invF and invG encode homologues of the AraC and PulD family of proteins. Mol Microbiol. 1994 Aug;13(4):555–568. doi: 10.1111/j.1365-2958.1994.tb00450.x. [DOI] [PubMed] [Google Scholar]
  35. Kaniga K., Delor I., Cornelis G. R. A wide-host-range suicide vector for improving reverse genetics in gram-negative bacteria: inactivation of the blaA gene of Yersinia enterocolitica. Gene. 1991 Dec 20;109(1):137–141. doi: 10.1016/0378-1119(91)90599-7. [DOI] [PubMed] [Google Scholar]
  36. Kihara M., Homma M., Kutsukake K., Macnab R. M. Flagellar switch of Salmonella typhimurium: gene sequences and deduced protein sequences. J Bacteriol. 1989 Jun;171(6):3247–3257. doi: 10.1128/jb.171.6.3247-3257.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  37. Kornacker M. G., Newton A. Information essential for cell-cycle-dependent secretion of the 591-residue Caulobacter hook protein is confined to a 21-amino-acid sequence near the N-terminus. Mol Microbiol. 1994 Oct;14(1):73–85. doi: 10.1111/j.1365-2958.1994.tb01268.x. [DOI] [PubMed] [Google Scholar]
  38. Kyte J., Doolittle R. F. A simple method for displaying the hydropathic character of a protein. J Mol Biol. 1982 May 5;157(1):105–132. doi: 10.1016/0022-2836(82)90515-0. [DOI] [PubMed] [Google Scholar]
  39. Lidell M. C., Hutcheson S. W. Characterization of the hrpJ and hrpU operons of Pseudomonas syringae pv. syringae Pss61: similarity with components of enteric bacteria involved in flagellar biogenesis and demonstration of their role in HarpinPss secretion. Mol Plant Microbe Interact. 1994 Jul-Aug;7(4):488–497. doi: 10.1094/mpmi-7-0488. [DOI] [PubMed] [Google Scholar]
  40. Lindgren P. B., Peet R. C., Panopoulos N. J. Gene cluster of Pseudomonas syringae pv. "phaseolicola" controls pathogenicity of bean plants and hypersensitivity of nonhost plants. J Bacteriol. 1986 Nov;168(2):512–522. doi: 10.1128/jb.168.2.512-522.1986. [DOI] [PMC free article] [PubMed] [Google Scholar]
  41. Lonetto M. A., Brown K. L., Rudd K. E., Buttner M. J. Analysis of the Streptomyces coelicolor sigE gene reveals the existence of a subfamily of eubacterial RNA polymerase sigma factors involved in the regulation of extracytoplasmic functions. Proc Natl Acad Sci U S A. 1994 Aug 2;91(16):7573–7577. doi: 10.1073/pnas.91.16.7573. [DOI] [PMC free article] [PubMed] [Google Scholar]
  42. Macnab R. M. Genetics and biogenesis of bacterial flagella. Annu Rev Genet. 1992;26:131–158. doi: 10.1146/annurev.ge.26.120192.001023. [DOI] [PubMed] [Google Scholar]
  43. Malakooti J., Ely B., Matsumura P. Molecular characterization, nucleotide sequence, and expression of the fliO, fliP, fliQ, and fliR genes of Escherichia coli. J Bacteriol. 1994 Jan;176(1):189–197. doi: 10.1128/jb.176.1.189-197.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  44. Malakooti J., Komeda Y., Matsumura P. DNA sequence analysis, gene product identification, and localization of flagellar motor components of Escherichia coli. J Bacteriol. 1989 May;171(5):2728–2734. doi: 10.1128/jb.171.5.2728-2734.1989. [DOI] [PMC free article] [PubMed] [Google Scholar]
  45. Michiels T., Vanooteghem J. C., Lambert de Rouvroit C., China B., Gustin A., Boudry P., Cornelis G. R. Analysis of virC, an operon involved in the secretion of Yop proteins by Yersinia enterocolitica. J Bacteriol. 1991 Aug;173(16):4994–5009. doi: 10.1128/jb.173.16.4994-5009.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  46. Miller V. L., Mekalanos J. J. A novel suicide vector and its use in construction of insertion mutations: osmoregulation of outer membrane proteins and virulence determinants in Vibrio cholerae requires toxR. J Bacteriol. 1988 Jun;170(6):2575–2583. doi: 10.1128/jb.170.6.2575-2583.1988. [DOI] [PMC free article] [PubMed] [Google Scholar]
  47. Minamino T., Iino T., Kutuskake K. Molecular characterization of the Salmonella typhimurium flhB operon and its protein products. J Bacteriol. 1994 Dec;176(24):7630–7637. doi: 10.1128/jb.176.24.7630-7637.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  48. Mulholland V., Hinton J. C., Sidebotham J., Toth I. K., Hyman L. J., Pérombelon M. C., Reeves P. J., Salmond G. P. A pleiotropic reduced virulence (Rvi-) mutant of Erwinia carotovora subspecies atroseptica is defective in flagella assembly proteins that are conserved in plant and animal bacterial pathogens. Mol Microbiol. 1993 Jul;9(2):343–356. doi: 10.1111/j.1365-2958.1993.tb01695.x. [DOI] [PubMed] [Google Scholar]
  49. Parsot C., Ménard R., Gounon P., Sansonetti P. J. Enhanced secretion through the Shigella flexneri Mxi-Spa translocon leads to assembly of extracellular proteins into macromolecular structures. Mol Microbiol. 1995 Apr;16(2):291–300. doi: 10.1111/j.1365-2958.1995.tb02301.x. [DOI] [PubMed] [Google Scholar]
  50. Plano G. V., Barve S. S., Straley S. C. LcrD, a membrane-bound regulator of the Yersinia pestis low-calcium response. J Bacteriol. 1991 Nov;173(22):7293–7303. doi: 10.1128/jb.173.22.7293-7303.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  51. Ramakrishnan G., Zhao J. L., Newton A. Multiple structural proteins are required for both transcriptional activation and negative autoregulation of Caulobacter crescentus flagellar genes. J Bacteriol. 1994 Dec;176(24):7587–7600. doi: 10.1128/jb.176.24.7587-7600.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  52. Ramakrishnan G., Zhao J. L., Newton A. The cell cycle-regulated flagellar gene flbF of Caulobacter crescentus is homologous to a virulence locus (lcrD) of Yersinia pestis. J Bacteriol. 1991 Nov;173(22):7283–7292. doi: 10.1128/jb.173.22.7283-7292.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  53. Rosqvist R., Magnusson K. E., Wolf-Watz H. Target cell contact triggers expression and polarized transfer of Yersinia YopE cytotoxin into mammalian cells. EMBO J. 1994 Feb 15;13(4):964–972. doi: 10.1002/j.1460-2075.1994.tb06341.x. [DOI] [PMC free article] [PubMed] [Google Scholar]
  54. Salmond G. P., Reeves P. J. Membrane traffic wardens and protein secretion in gram-negative bacteria. Trends Biochem Sci. 1993 Jan;18(1):7–12. doi: 10.1016/0968-0004(93)90080-7. [DOI] [PubMed] [Google Scholar]
  55. Sanger F., Nicklen S., Coulson A. R. DNA sequencing with chain-terminating inhibitors. Proc Natl Acad Sci U S A. 1977 Dec;74(12):5463–5467. doi: 10.1073/pnas.74.12.5463. [DOI] [PMC free article] [PubMed] [Google Scholar]
  56. Santana M., Ionescu M. S., Vertes A., Longin R., Kunst F., Danchin A., Glaser P. Bacillus subtilis F0F1 ATPase: DNA sequence of the atp operon and characterization of atp mutants. J Bacteriol. 1994 Nov;176(22):6802–6811. doi: 10.1128/jb.176.22.6802-6811.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  57. Sasakawa C., Komatsu K., Tobe T., Suzuki T., Yoshikawa M. Eight genes in region 5 that form an operon are essential for invasion of epithelial cells by Shigella flexneri 2a. J Bacteriol. 1993 Apr;175(8):2334–2346. doi: 10.1128/jb.175.8.2334-2346.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  58. Shen H., Keen N. T. Characterization of the promoter of avirulence gene D from Pseudomonas syringae pv. tomato. J Bacteriol. 1993 Sep;175(18):5916–5924. doi: 10.1128/jb.175.18.5916-5924.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  59. Sory M. P., Cornelis G. R. Translocation of a hybrid YopE-adenylate cyclase from Yersinia enterocolitica into HeLa cells. Mol Microbiol. 1994 Nov;14(3):583–594. doi: 10.1111/j.1365-2958.1994.tb02191.x. [DOI] [PubMed] [Google Scholar]
  60. Staskawicz B. J., Ausubel F. M., Baker B. J., Ellis J. G., Jones J. D. Molecular genetics of plant disease resistance. Science. 1995 May 5;268(5211):661–667. doi: 10.1126/science.7732374. [DOI] [PubMed] [Google Scholar]
  61. Van Gijsegem F., Genin S., Boucher C. Conservation of secretion pathways for pathogenicity determinants of plant and animal bacteria. Trends Microbiol. 1993 Aug;1(5):175–180. doi: 10.1016/0966-842x(93)90087-8. [DOI] [PubMed] [Google Scholar]
  62. Van Gijsegem F., Gough C., Zischek C., Niqueux E., Arlat M., Genin S., Barberis P., German S., Castello P., Boucher C. The hrp gene locus of Pseudomonas solanacearum, which controls the production of a type III secretion system, encodes eight proteins related to components of the bacterial flagellar biogenesis complex. Mol Microbiol. 1995 Mar;15(6):1095–1114. doi: 10.1111/j.1365-2958.1995.tb02284.x. [DOI] [PubMed] [Google Scholar]
  63. Venkatesan M. M., Buysse J. M., Oaks E. V. Surface presentation of Shigella flexneri invasion plasmid antigens requires the products of the spa locus. J Bacteriol. 1992 Mar;174(6):1990–2001. doi: 10.1128/jb.174.6.1990-2001.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  64. Viitanen A. M., Toivanen P., Skurnik M. The lcrE gene is part of an operon in the lcr region of Yersinia enterocolitica O:3. J Bacteriol. 1990 Jun;172(6):3152–3162. doi: 10.1128/jb.172.6.3152-3162.1990. [DOI] [PMC free article] [PubMed] [Google Scholar]
  65. Vogler A. P., Homma M., Irikura V. M., Macnab R. M. Salmonella typhimurium mutants defective in flagellar filament regrowth and sequence similarity of FliI to F0F1, vacuolar, and archaebacterial ATPase subunits. J Bacteriol. 1991 Jun;173(11):3564–3572. doi: 10.1128/jb.173.11.3564-3572.1991. [DOI] [PMC free article] [PubMed] [Google Scholar]
  66. Walker J. E., Saraste M., Gay N. J. The unc operon. Nucleotide sequence, regulation and structure of ATP-synthase. Biochim Biophys Acta. 1984 Sep 6;768(2):164–200. doi: 10.1016/0304-4173(84)90003-x. [DOI] [PubMed] [Google Scholar]
  67. Wei Z. M., Beer S. V. HrpI of Erwinia amylovora functions in secretion of harpin and is a member of a new protein family. J Bacteriol. 1993 Dec;175(24):7958–7967. doi: 10.1128/jb.175.24.7958-7967.1993. [DOI] [PMC free article] [PubMed] [Google Scholar]
  68. Wei Z. M., Beer S. V. hrpL activates Erwinia amylovora hrp gene transcription and is a member of the ECF subfamily of sigma factors. J Bacteriol. 1995 Nov;177(21):6201–6210. doi: 10.1128/jb.177.21.6201-6210.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  69. Wei Z. M., Laby R. J., Zumoff C. H., Bauer D. W., He S. Y., Collmer A., Beer S. V. Harpin, elicitor of the hypersensitive response produced by the plant pathogen Erwinia amylovora. Science. 1992 Jul 3;257(5066):85–88. doi: 10.1126/science.1621099. [DOI] [PubMed] [Google Scholar]
  70. Wei Z. M., Sneath B. J., Beer S. V. Expression of Erwinia amylovora hrp genes in response to environmental stimuli. J Bacteriol. 1992 Mar;174(6):1875–1882. doi: 10.1128/jb.174.6.1875-1882.1992. [DOI] [PMC free article] [PubMed] [Google Scholar]
  71. Woestyn S., Allaoui A., Wattiau P., Cornelis G. R. YscN, the putative energizer of the Yersinia Yop secretion machinery. J Bacteriol. 1994 Mar;176(6):1561–1569. doi: 10.1128/jb.176.6.1561-1569.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  72. Xiao Y., Hutcheson S. W. A single promoter sequence recognized by a newly identified alternate sigma factor directs expression of pathogenicity and host range determinants in Pseudomonas syringae. J Bacteriol. 1994 May;176(10):3089–3091. doi: 10.1128/jb.176.10.3089-3091.1994. [DOI] [PMC free article] [PubMed] [Google Scholar]
  73. Yother J., Goguen J. D. Isolation and characterization of Ca2+-blind mutants of Yersinia pestis. J Bacteriol. 1985 Nov;164(2):704–711. doi: 10.1128/jb.164.2.704-711.1985. [DOI] [PMC free article] [PubMed] [Google Scholar]
  74. Zhuang W. Y., Shapiro L. Caulobacter FliQ and FliR membrane proteins, required for flagellar biogenesis and cell division, belong to a family of virulence factor export proteins. J Bacteriol. 1995 Jan;177(2):343–356. doi: 10.1128/jb.177.2.343-356.1995. [DOI] [PMC free article] [PubMed] [Google Scholar]
  75. Zuberi A. R., Ying C., Bischoff D. S., Ordal G. W. Gene-protein relationships in the flagellar hook-basal body complex of Bacillus subtilis: sequences of the flgB, flgC, flgG, fliE and fliF genes. Gene. 1991 May 15;101(1):23–31. doi: 10.1016/0378-1119(91)90220-6. [DOI] [PubMed] [Google Scholar]

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