Skip to main content
Infection and Immunity logoLink to Infection and Immunity
. 1985 Jul;49(1):46–51. doi: 10.1128/iai.49.1.46-51.1985

Detection of genes for heat-stable enterotoxin I in Escherichia coli strains isolated in Brazil.

R Maas, R M Silva, T A Gomes, L R Trabulsi, W K Maas
PMCID: PMC262056  PMID: 3891629

Abstract

Heat-stable enterotoxin I (STI) can be assayed in intestinal loops of pigs and rabbits and in the gut of infant mice. To produce a simpler and more discriminating assay procedure, we used three gene probes corresponding to three forms of STI called STIa, STIb, and STIc. We tested 159 Brazilian isolates, of which 40 were positive in the infant mouse assay. The STIb and STIc probes are similar (93% DNA homology) and are both different from the STIa probe (70% DNA homology). Of 33 strains that were still active for STI 3 years after their isolation, 25 reacted with both the STIb and STIc probes, 4 reacted with the STIc probe only, and 7 reacted strongly with the STIa probe and weakly or not at all with the other probes. Two strains reacted with all three probes. Further analysis showed that each of these two strains contains a small plasmid that reacts with the STIa probe and a large plasmid that reacts with the STIc probe in one strain and weakly with both the STIa and STIc probes in the other strain. It was also shown that the STIa probe reacts with the cloning vehicle pACYC184 used for the cloning of STIc. We conclude that the gene probes used can identify most STI-producing strains and that in cases of positive responses with several probes careful scrutiny is necessary for analysis.

Full text

PDF
46

Images in this article

Selected References

These references are in PubMed. This may not be the complete list of references from this article.

  1. Aimoto S., Takao T., Shimonishi Y., Hara S., Takeda T., Takeda Y., Miwatani T. Amino-acid sequence of a heat-stable enterotoxin produced by human enterotoxigenic Escherichia coli. Eur J Biochem. 1982 Dec 15;129(2):257–263. doi: 10.1111/j.1432-1033.1982.tb07047.x. [DOI] [PubMed] [Google Scholar]
  2. Dalbadie-McFarland G., Cohen L. W., Riggs A. D., Morin C., Itakura K., Richards J. H. Oligonucleotide-directed mutagenesis as a general and powerful method for studies of protein function. Proc Natl Acad Sci U S A. 1982 Nov;79(21):6409–6413. doi: 10.1073/pnas.79.21.6409. [DOI] [PMC free article] [PubMed] [Google Scholar]
  3. Gyles C. L. Limitations of the infant mouse test for Escherichia coli heat stable enterotoxin. Can J Comp Med. 1979 Oct;43(4):371–379. [PMC free article] [PubMed] [Google Scholar]
  4. Kado C. I., Liu S. T. Rapid procedure for detection and isolation of large and small plasmids. J Bacteriol. 1981 Mar;145(3):1365–1373. doi: 10.1128/jb.145.3.1365-1373.1981. [DOI] [PMC free article] [PubMed] [Google Scholar]
  5. Maas R. An improved colony hybridization method with significantly increased sensitivity for detection of single genes. Plasmid. 1983 Nov;10(3):296–298. doi: 10.1016/0147-619x(83)90045-8. [DOI] [PubMed] [Google Scholar]
  6. Meinkoth J., Wahl G. Hybridization of nucleic acids immobilized on solid supports. Anal Biochem. 1984 May 1;138(2):267–284. doi: 10.1016/0003-2697(84)90808-x. [DOI] [PubMed] [Google Scholar]
  7. Moseley S. L., Echeverria P., Seriwatana J., Tirapat C., Chaicumpa W., Sakuldaipeara T., Falkow S. Identification of enterotoxigenic Escherichia coli by colony hybridization using three enterotoxin gene probes. J Infect Dis. 1982 Jun;145(6):863–869. doi: 10.1093/infdis/145.6.863. [DOI] [PubMed] [Google Scholar]
  8. Moseley S. L., Hardy J. W., Hug M. I., Echeverria P., Falkow S. Isolation and nucleotide sequence determination of a gene encoding a heat-stable enterotoxin of Escherichia coli. Infect Immun. 1983 Mar;39(3):1167–1174. doi: 10.1128/iai.39.3.1167-1174.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]
  9. Moseley S. L., Huq I., Alim A. R., So M., Samadpour-Motalebi M., Falkow S. Detection of enterotoxigenic Escherichia coli by DNA colony hybridization. J Infect Dis. 1980 Dec;142(6):892–898. doi: 10.1093/infdis/142.6.892. [DOI] [PubMed] [Google Scholar]
  10. Reis M. H., Matos D. P., de Castro A. F., Toledo M. R., Trabulsi L. R. Relationship among enterotoxigenic phenotypes, serotypes, and sources of strains in enterotoxigenic Escherichia coli. Infect Immun. 1980 Apr;28(1):24–27. doi: 10.1128/iai.28.1.24-27.1980. [DOI] [PMC free article] [PubMed] [Google Scholar]
  11. Rigby P. W., Dieckmann M., Rhodes C., Berg P. Labeling deoxyribonucleic acid to high specific activity in vitro by nick translation with DNA polymerase I. J Mol Biol. 1977 Jun 15;113(1):237–251. doi: 10.1016/0022-2836(77)90052-3. [DOI] [PubMed] [Google Scholar]
  12. So M., McCarthy B. J. Nucleotide sequence of the bacterial transposon Tn1681 encoding a heat-stable (ST) toxin and its identification in enterotoxigenic Escherichia coli strains. Proc Natl Acad Sci U S A. 1980 Jul;77(7):4011–4015. doi: 10.1073/pnas.77.7.4011. [DOI] [PMC free article] [PubMed] [Google Scholar]
  13. Vogelstein B., Gillespie D. Preparative and analytical purification of DNA from agarose. Proc Natl Acad Sci U S A. 1979 Feb;76(2):615–619. doi: 10.1073/pnas.76.2.615. [DOI] [PMC free article] [PubMed] [Google Scholar]
  14. Yamamoto T., Yokota T. Plasmids of enterotoxigenic Escherichia coli H10407: evidence for two heat-stable enterotoxin genes and a conjugal transfer system. J Bacteriol. 1983 Mar;153(3):1352–1360. doi: 10.1128/jb.153.3.1352-1360.1983. [DOI] [PMC free article] [PubMed] [Google Scholar]

Articles from Infection and Immunity are provided here courtesy of American Society for Microbiology (ASM)

RESOURCES