[Isolation and characteristics of E. coli plasmid-determined K88 antigen].

The advantage of ultracentrifugation over isoelectric focusing in the isolation of antigen K88 from E. coli is shown. The production of antigen K88 is recA-independent. The antigen has been found to be nontoxic for mice, to have the isoionic point at pH 4.1 and the sedimentation coefficient 16.6S, to completely consist of protein subunits of 25,000 daltons. The expression of antigen K88 enhances the adhesive properties of the host cell. No relationship between antigen K88 and the supposed adhesins of both Vibrio cholerae biotypes has been established.