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: Growth-rate-dependent synthesis of K99 fimbrial subunits is regulated at the level of transcription.
    Author: van der Woude MW, Arts PA, Bakker D, van Verseveld HW, de Graaf FK.
    Journal: J Gen Microbiol; 1990 May; 136(5):897-903. PubMed ID: 1974281.
    Abstract:
    Increase in the production of the fimbrial adhesion K99 by enterotoxigenic Escherichia coli in continuous cultures at specific growth rates above 0.25 h-1 was shown to be independent of the nature of the growth-limiting nutrient. The correlation between specific growth rate and K99 production was also found to be independent of the copy number of the K99 operon. Introduction of additional copies of the K99 regulatory region did not affect growth-rate-dependent K99 production in wild-type strains, indicating that no hypothetical regulatory host factor is titrated by the K99 regulatory region. Regulation at the transcriptional level was measured with galactokinase gene fusions. The transcription of the fimbrial subunit gene increased with an increase in specific growth rate. This growth-rate-dependent transcription was found to originate from the strong promoter PA. Transcription originating from the weaker promoter PB was independent of growth rate. The results indicated that transcriptional regulation at PA is involved in the growth-rate-dependent regulation of K99 production.
    [Abstract] [Full Text] [Related] [New Search]