Episome-carried surface antigen K88 of Escherichia coli. I. Transmission of the determinant of the K88 antigen and influence on the transfer of chromosomal markers.

Ørskov, Ida (Statens Seruminstitut, Copenhagen, Denmark), and Frits Ørskov. Episome-carried surface antigen K88 of Escherichia coli. I. Transmission of the determinant of the K88 antigen and influence on the transfer of chromosomal markers. J. Bacteriol. 91:69-75. 1966.-The transmission of the determinant of the Escherichia coli K88 antigen in mixed cultures of E. coli strains is described. The K88 factor could not be transferred by filtrates, nor could responsible phages or colicines be detected. Acriflavine was shown to "cure" the bacteria for the K88 antigen. Generally, the strains having acquired the K88 antigen also acquired the ability to transfer chromosomal markers, but this ability was in some cases retained by segregants which had lost the K88 antigen. Introduction into an F(+) strain caused reduction of the recombination frequency and disappearance of the f(+) antigen. Not all wild-type strains with the K88 antigen are genetic donors of this antigen, at least not to a discernible degree. It was concluded that the K88 antigen determinant is carried by an episome.