[Conjugational transfer of chromosomal markers in the Erwinia chrysanthemi bacterial system. II. Characteristics of the donor strain of Erwinia chrysanthemi VY1-10].

Some properties of the donor Erwinia chrysanthemi VY1-10 strain are similar to those of Hfr donors of Escherichia coli. These are stable inheritance of the Flac plasmid and the capacity for linear and polarized transfer of the chromosome from one oriT site in the following order: O ... thr, leu ... pro ... his. In addition to the ability to transfer its own chromosomal markers, the donor E. chrysanthemi VY1-10 also transfers lac+ marker during initial conjugational steps. The lac+ marker can be detected in recombinants as a structure similar to E. coli K-12 Flac plasmid which was used to obtain the donor strain. It is supposed that such properties are determined either by unusual integration of Flac plasmid or by the unstable Hfr state.