Antibiotic-free segregational plasmid stabilization in Escherichia coli owing to the knockout of triosephosphate isomerase (tpiA)

Antibiotic-free segregational plasmid stabilization in Escherichia coli owing to the knockout of triosephosphate isomerase (tpiA)

BACKGROUND Segregational stability of plasmids is of major concern for recombinant bacterial production strains. One of the best strategies to counteract plasmid loss is the use of auxotrophic mutants which are complemented with the lacking gene along with the product-relevant ones. However, these knockout mutants often show unwanted growth in complex standard media or no growth at all under un...

Escherichia coli strains that allow antibiotic-free plasmid selection and maintenance by repressor titration.

We report the construction of two novel Escherichia coli strains (DH1lacdapD and DH1lacP2dapD) that facilitate the antibiotic-free selection and stable maintenance of recombinant plasmids in complex media. They contain the essential chromosomal gene, dapD, under the control of the lac operator/promoter. Unless supplemented with IPTG (which induces expression of dapD) or DAP, these cells lyse. H...

The mechanism of the triosephosphate isomerase reaction.

The interconversion of dihydroxyacetone phosphate and glyceraldehyde 3-phosphate catalyzed by the enzyme triosephosphate isomerase was first demonstrated by Meyerhof and Kiessling (1). Since then studies with the enzyme have disclosed little about the mechanism of this reaction. Such an interconversion may be envisioned as occurring by formation of an enediol as, based on chemical analogy (2)) ...

Study of antimicrobial susceptibility and plasmid analysis of Escherichia coli in Iran, Urmia

from linguistics to literature: a linguistic approach to the study of linguistic deviations in the turkish divan of shahriar

chapter i provides an overview of structural linguistics and touches upon the saussurean dichotomies with the final goal of exploring their relevance to the stylistic studies of literature. to provide evidence for the singificance of the study, chapter ii deals with the controversial issue of linguistics and literature, and presents opposing views which, at the same time, have been central to t...