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PubMed · 6938758

Monomer plasmid DNA transforms Streptococcus pneumoniae.

C W Saunders·W R Guild
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Abstract

The covalently closed (CC) monomer form of plasmid pMV158 was found to transform pneumococcus (Streptococcus pneumoniae) and to do so with two-hit kinetics. The evidence came from analysis of the behavior of the transforming activity in fractions from preparative gel electrophoresis. Activity in the first major peak to elute (i) co-eluted with monomer CC as detected on analytical gels, (ii) banded as CC in dye-buoyancy gradients, (iii) sedimented with the velocity expected for monomer CC, and (iv) gave two-hit kinetics as functions of both concentration and time of exposure of the cells to DNA. A second major peak of activity behaved physically as though mostly due to dimer CC forms and gave single-hit response curves. Because almost no dimer was detectable optically on analytical gels of starting preparations, its specific activity was high relative to that of the monomers.

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Centrifugation, Density GradientDNA, BacterialDNA, CircularElectrophoresis, Agar GelKineticsPlasmidsStreptococcus pneumoniaeTransformation, GeneticJournal ArticleResearch Support, U.S. Gov't, Non-P.H.S.Research Support, U.S. Gov't, P.H.S.

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C W Saunders, W R Guild. 1981. Monomer plasmid DNA transforms Streptococcus pneumoniae.. https://doi.org/10.1007/bf00339005

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