[Genetic transfer of pAP38, pAP39, and pAP41 plasmids into E. coli, Erwinia, and Hafnia strains].

Genetic transfer factors pAP38, pAP39 and pAP41 can be transferred to E. coli, both typed and untypecd, as well as to Erwinia and Hafnia strains, with different frequency (10(-2) to 10(-8)). The transconjugates thus obtained possess donor activity and can transfer the factors they have received to recipient E.

[Morphological characteristics and biological properties of morphological mutants of Escherichia coli K12].

E. coli mutants K12, PA6021, and AB312 characterised by changed morphology were obtained. Various morphological elements encountered in the mutant populations, and the capacity to phenotypical reversion are described.