Ar. Wood et al., A NATIVE PLASMID OF PASTURELLA-HAEMOLYTICA SEROTYPE-A1 - DNA-SEQUENCEANALYSIS AND INVESTIGATION OF ITS POTENTIAL AS A VECTOR, Research in Veterinary Science, 58(2), 1995, pp. 163-168
The complete nucleotide sequence of a 4.3 kilobase pair plasmid, pAB2,
isolated from a bovine strain of Pasteurella haemolytica serotype Al,
was determined. It encodes a Rob-1 type beta-lactamase and a region w
ith homology to the mobilisation (mob) region of the Escherichia coli
plasmid, ColE1. An insertion mutant of pAB2 (pTC2/81) carrying a copy
of Tn5 was transferred to E coli K12 by conjugation. Subsequently pTC2
/81 could be transferred by transformation to E coli HB101, but not to
P haemolytica serotypes Al or A2. However, a derivative of this const
ruct containing only a fragment of the Tn5 insertion sequence was able
to transform P haemolytica. A further construct containing a fragment
of the P haemolytica Al leucotoxin A gene, was similarly restricted t
o transforming E coil. These results demonstrate that the pAB2 plasmid
is capable of acting as an E coli/P haemolytica shuttle vector. Howev
er, the nature of the cloned DNA sequences are important to transforma
tion.