Plasmid Transfer into the Homoacetogen Acetobacterium woodii by Electroporation and Conjugation

Shuttle vectors (pMS3 and pMS4) which replicated in Escherichia coli and in gram-positive Acetobacterium woodii were constructed by ligating the replication origin of plasmid pAMβ1 with the E. coli cloning vector pUC19 and the tetM gene of streptococcal transposon Tn916. Electrotransformation of A. woodii was achieved at frequencies of 4.5 × 10³ transformants per μg of plasmid DNA. For conjugal plasmid transfer, the mobilizable shuttle vector pKV12 was constructed by cloning the tetM gene into pAT187. Mating of E. coli containing pKV12 with A. woodii resulted in transfer frequencies of 3 × 10^-6 to 7 × 10^-6 per donor or recipient.