Few vectors suitable for cloning in Actinobacillus actinomycetemcomita
ns, a periodontal pathogen, have been described. These plasmids were b
ased either on the native A. actinomycetemcomitans replicon, pVT736-1,
or derivatives of the IncP and IncQ family of plasmids. Their usefuln
ess as cloning vectors is limited because of instability or size. Ther
efore, the ability of additional replicons to function in A. actinomyc
etemcomitans was evaluated. Derivatives of p15A, ColE1/ fl, and pWV01
transformed A. actinomycetemcomitans efficiently and exhibited no stru
ctural instability in the new host. The stable maintenance of A. actin
omycetemcomitans-specific DNA fragments inserted into the p15A derivat
ive, pDMG4, demonstrated the ability of this plasmid to function as a
cloning vector. In addition, pVT736-1 was used to clone selectable mar
kers directly into A. actinomycetemcomitans. These constructs were str
ucturally and segregationally stable. (C) 1996 Academic Press, Inc.