These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


Pubmed for Handhelds

PUBMED FOR HANDHELDS

Search MEDLINE/PubMed

  • Title: Construction of plasmids useful for production of the B subunit of cholera toxin from Vibrio cholerae or a heat-labile enterotoxin from enterotoxigenic Escherichia coli.
    Author: Tsuji T, Kato M, Kato Y, Kawase H, Imamura S, Miyama A.
    Journal: Eur J Epidemiol; 1994 Aug; 10(4):393-8. PubMed ID: 7843342.
    Abstract:
    A simple method to construct the plasmids producing the B subunit of porcine or human heatlabile enterotoxin or cholera toxin was developed, and the B subunits produced by the resulting plasmids were purified. The gene of LTp from pEWD 299 was ligated to pHSG 396 or pBluescript SK(+)-1 and the vector carrying one Xbal and EcoR1 site in the LTp-A gene was constructed. The Xbal-EcoR1 fragment of LTp-A gene was exchanged for the multicloning site of pHSG 396 containing Xbal, BamH1, Cla 1, Kpn1, Sac1 and EcoR1 sites. This plasmid (pTSU28) produced the LTp-B subunit. Moreover, the fragment of the LTp-B gene of pTSU 28 was exchanged by the EcoR1-HindIII fragment of LTh-B from E. coli H10407 strain (pTSU 35) or by the Cla 1-Hind III fragment of CT-B gene amplified by the PCR procedure with the chromosomal DNA of V. cholerae 86KT25 (pTSU 32). The DNA sequence of the CT-B subunit amplified by PCR procedure was compared and found identical to that cited in the literature [11]. After these plasmids were transformed into E. coli MV 1184 strain, the toxins produced by them were purified using a Bio-Gel A 5m affinity column for both LT-Bs and an immunobilized D-galactose affinity column for CT-B. Though both columns absorbed only the B subunit, the eluates contained a single protein corresponding to the B subunit, suggesting that each mutant produces only the B subunit.
    [Abstract] [Full Text] [Related] [New Search]