Construction of novel shuttle vectors for use between moderately halophilic bacteria and Escherichia coli.

Shuttle vectors useful for the genetic manipulation of several moderately halophilic bacteria have been constructed. These vectors are based on the minimal replicon of pCM1, a cryptic plasmid from Chromohalobacter marismortui, combined with the useful properties of pUC18 plasmid (i.e., small size, high copy number, multiple cloning sites, lacZ fragment), as well as with the trimethoprim resistance gene as a selection marker for moderate halophiles. These vectors can be efficiently transferred by RP4-mediated conjugation from Escherichia coli to the moderate halophiles Chromohalobacter marismortui, Deleya halophila, Halomonas elongata, Halomonas subglaciescola, and Volcaniella eurihalina.