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: The cloning and overproduction of Escherichia coli uracil-DNA glycosylase.
    Author: Duncan BK, Chambers JA.
    Journal: Gene; 1984 May; 28(2):211-9. PubMed ID: 6234205.
    Abstract:
    Escherichia coli cells containing elevated levels of the DNA repair enzyme uracil-DNA glycosylase (the ung gene product) have been constructed by in vitro recombination methods. First, lambdanadB transducing phages were isolated from two E. coli DNA libraries by selection of nicotinate-independent lysogens. lambdanadB phage from one of the libraries were also ung+ and carried the ung-nadB genes on an 8.3-kb HindIII restriction fragment. The ung and nadB genes were subcloned into plasmids and a restriction map of the ung region of the E. coli chromosome was constructed. The uracil glycosylase gene was localized to a 1.4-kb restriction fragment by subcloning the gene into pBR322. Uracil glycosylase was overproduced (relative to the specific activity of wild type cells) by about two-fold in lambdaung lysogens and by 15- to 20-fold in cells containing pBR322ung derivatives. When the ung gene and its promoter were placed downstream from the bacteriophage lambdaPL promoter in the plasmid pKC30, uracil glycosylase production was heat-induced to more than 100-fold above the levels of a wild-type cell. By relating the insertion orientation of the lambdaung gene in the plasmid pKC30 to its orientation in lambdaung-nadB transducing phages, the transcription direction of the ung gene on the E. coli linkage map was found to be clockwise.
    [Abstract] [Full Text] [Related] [New Search]