The role of outer membrane proteins of E. coli K12 in the cell wall permeability for plasmid DNA

The Escherichia coli K12 mutant having the increased efficiency for plasmid DNA transformation has been shown to possess the different protein composition of the outer membrane of the cellular wall, as compared with that of the wild type strain. Correlation between the level of calcium-dependent plasmid transformation and the portion of infections DNA bound with cytoplasmic membranes is demonstrated for the Escherichia coli cells mutant for outer membrane structure and ability to be transformed by plasmid DNA.