Restriction digests of the clone give the following sizes (kb): EcoRI--6.5, 2.0; BamHI--4.4, 4.0; HindIII--5.0, 3.4; PstI--2.45 (doublet); 1.5, 0.96, 0.84. Suggested conditions for electroporation in these bacterial strains: E. coli C600Sm, fields strength 20 kV/cm, pulse length 5 to 12 msec; Erwinia amylovora Ea7/74Sm, 25 kV/cm, 5 msec; E. amylovora Ea1/79Sm, 12.5 kV/cm, 17.5 msec. To propagate the plasmid, the host must provide the bacteriophage fd gene 2 product. Suicide plasmid for transposon-mediated or site-directed mutagenesis of Erwinia amylovora and Escherichia coli after electroporation. The order of the major features in this plasmid is: EcoRI - ampR - fd ori - EcoRI - Tn5/kanR (6.5 kb). |