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

Journal of Bacteriology - Tập 170 Số 6 - Trang 2575-2583 - 1988
Virginia L. Miller1, John J. Mekalanos1
1Department of Microbiology and Molecular Genetics, Harvard Medical School, Boston, Massachusetts 02115

Tóm tắt

The toxR gene of Vibrio cholerae encodes a transmembrane, DNA-binding protein that activates transcription of the cholera toxin operon and a gene (tcpA) for the major subunit of a pilus colonization factor. We constructed site-directed insertion mutations in the toxR gene by a novel method employing the chromosomal integration of a mobilizable suicide plasmid containing a portion of the toxR coding sequence. Mutants containing these new toxR alleles had an altered outer membrane protein profile, suggesting that two major outer membrane proteins (OmpT and OmpU) might be under the control of toxR. Physiological studies indicated that varying the concentration of the amino acids asparagine, arginine, glutamate, and serine caused coordinate changes in the expression of cholera toxin, TcpA, OmpT, and OmpU. Changes in the osmolarity of a tryptone-based medium also produced coordinate changes in the expression of these proteins. Other environmental signals (temperature and pH) had a more pronounced effect on the expression of cholera toxin and TcpA than they did on the outer membrane proteins. These results suggest that certain environmental signals (i.e., osmolarity and the presence of amino acids) are tightly coupled to the expression of toxR-regulated proteins and therefore may be signals that are directly sensed by the ToxR protein.

Từ khóa


Tài liệu tham khảo

Betley , M. J. , V. I. Miller , and J. J. Mekalanos . 1986 . Genetics of bacterial enterotoxins. Annu . Rev. Microbiol. 40 : 577 - 605 .

Calderwood , S. B. , and J. J. Mekalanos . 1987 . Iron regulation of Shiga-like toxin expression in Escherichia coli is mediated by the fur locus . J. Bacteriol. 169 : 4759 - 4764 .

Callahan , L. T. , and S. H. Richardson . 1973 . Biochemistry of Vibrio cholerae virulence. III. Nutritional requirements for toxin production and the effects of pH on toxin elaboration in chemically defined media . Infect. Immun. 7 : 567 - 574 .

Hall , M. N. , and T. J. Silhavy . 1981 . Genetic analysis of the major outer membrane proteins of Escherichia coli. Annu . Rev. Genet. 15 : 91 - 142 .

Hall , M. N. , and T. J. Silhavy . 1981 . Genetic analysis of the ompB locus in Escherichia coli . J. Mol. Biol. 151 : 1 - 15 .

Holmes , R. K. , W. B. Baine , and M. L. Vasil . 1978 . Quantitative measurements of cholera enterotoxin in cultures of toxinogenic wild-type and nontoxinogenic mutant strains of Vibrio cholerae by using a sensitive and specific reversed passive hemagglutination assay for cholera enterotoxin . Infect. Immun. 19 : 101 - 106 .

Holmgren , J. 1973 . Comparison of the tissue receptors for Vibrio cholerae and Escherichia coli enterotoxins by means of gangliosides and natural toxoid . Infect. Immun. 8 : 851 - 853 .

Huq , A. , P. A. West , E. B. Small , M. I. Huq , and R. R. Colwell . 1984 . Influence of water temperature, salinity, and pH on the survival and growth of toxigenic Vibrio cholerae serovar 01 associated with live copepods in laboratory microcosms . Appl. Environ. Microbiol. 48 : 420424 .

Kelly , J. T. , and C. D. Parker . 1981 . Identification and preliminary characterization of Vibrio cholerae outer membrane proteins . J. Bacteriol. 145 : 1018 - 1024 .

Kolter , R. , M. Inuzuka , and D. R. Helinski . 1978 . Transcomplementation-dependent replication of a low molecular weight origin fragment from plasmid RK6 . Cell 15 : 1199 - 1208 .

Laimins , L. A. , D. B. Rhoads , and W. Epstein . 1981 . Osmotic control of kdp operon expression in Escherichia coli . Proc. Natl. Acad. Sci. USA 78 : 464 - 468 .

LeRudulier , D. , R. A. Strom , A. M. Dandekar , L. T. Smith , and R. C. Velentine . 1984 . Molecular biology of osmoregulation . Science 224 : 1064 - 1068 .

Maniatis T. E. F. Fritsch and J. Sambrook. 1982. Molecular cloning: a laboratory manual. Cold Spring Harbor Laboratory Cold Spring Harbor N.Y.

Maurelli , A. T. , B. Blackmon , and R. Curtiss III . 1984 . Temperature-dependent expression of virulence genes in Shigella species . Infect. Immun. 43 : 195 - 201 .

Mekalanos , J. J. 1983 . Duplication and amplification of toxin genes in Vibrio cholerae . Cell 35 : 253 - 263 .

Mekalanos , J. J. , R. J. Collier , and W. R. Romig . 1978 . Affinity filters, a new approach to the isolation of tox mutants of Vibrio cholerae . Proc. Natl. Acad. Sci. USA 75 : 941 - 945 .

Mekalanos , J. J. , S. Moseley , J. R. Murphy , and S. Falkow . 1982 . Isolation of enterotoxin structural gene deletion mutations in Vibrio cholerae induced by two mutagenic vibriophages . Proc. Natl. Acad. Sci. USA 79 : 151 - 155 .

Mekalanos , J. J. , D. J. Swartz , G. D. N. Pearson , N. Harford , F. Groyne , and M. de Wilde . 1983 . Cholera toxin genes: nucleotide sequence, deletion analysis and vaccine development . Nature (London) 306 : 551 - 557 .

Miller J. H. 1972. Experiments in molecular genetics. Cold Spring Harbor Laboratory Cold Spring Harbor N.Y.

Miller , V. L. , and J. J. Mekalanos . 1984 . Synthesis of cholera toxin is positively regulated at the transcriptional level by toxR . Proc. Natl. Acad. Sci. USA 81 : 3471 - 3475 .

Miller , V. L. , and J. J. Mekalanos . 1985 . Genetic analysis of the cholera toxin positive regulatory gene toxR . J. Bacteriol. 163 : 580 - 585 .

Miller , V. L. , R. K. Taylor , and J. J. Mekalanos . 1987 . Cholera toxin transcriptional activator ToxR is a transmembrane DNA binding protein . Cell 48 : 271 - 279 .

Murphy , J. R. , J. Skiver , and G. McBride . 1976 . Isolation and partial characterization of a corynebacteriophage 1 tox operator constitutive-like mutant Iysogen of Corynebacterium diphtheriae . J. Virol. 18 : 235 - 244 .

Sagar , I. K. , C. N. Nagesha , and J. V. Bhat . 1979 . Effect of metal ions on production of vascular permeability factor by 569B strain of Vibrio cholerae Ind . J. Med. Res. 69 : 18 - 25 .

Sagar , I. K. , C. N. Nagesha , and J. V. Bhat . 1981 . The role of trace elements and phosphates in the synthesis of vascularpermeability factor by Vibrio cholerae . J. Med. Microbiol. 14 : 243 - 250 .

Shimamura , T. , S. Watanabe , and S. Sasaki . 1985 . Enhancement of enterotoxin production by carbon dioxide in Vibrio cholerae . Infect. Immun. 49 : 455456 .

Simon , R. , U. Priefer , and A. Piihler . 1983 . A broad host range mobilization system for in vivo genetic engineering: transposon mutagenesis in gram negative bacteria . Bio/Technology 1 : 784 - 791 .

Stachel , S. E. , E. Messens , M. Van Montagu , and P. Zambryski . 1985 . Identification of the signal molecules produced by wounded plant cells that activate T-DNA transfer in Agrobacterium tumefaciens . Nature (London) 318 : 624 - 629 .

Straley , S. C. , and W. S. Bowmer . 1986 . Virulence genes regulated at the transcriptional level by Ca 2+ in Yersinia pestis include structural genes for outer membrane proteins . Infect. Immun. 51 : 445 - 454 .

Tamplin , M. L. , and R. R. Colwell . 1986 . Effects of microcosm salinity and organic substrate concentration on production of Vibrio cholerae enterotoxin . Appl. Environ. Microbiol. 52 : 297 - 301 .

Taylor , R. K. , V. L. Miller , D. B. Furlong , and J. J. Mekalanos . 1987 . Use of pho gene fusions to identify a pilus colonization factor coordinately regulated with cholera toxin . Proc. Natl. Acad. Sci. USA 84 : 2833 - 2837 .

Thuring , R. W. J. , J. P. M. Sanders , and P. Borst . 1975 . A freeze-squeeze method for recovering long DNA from agarose gels . Anal. Biochem. 66 : 213 - 220 .

Weiss , A. A. , and E. L. Hewlett . 1986 . Virulence factors of Bordetella pertussis. Annu . Rev. Microbiol. 40 : 661 - 686 .