Efficient cloning in Bacillus megaterium: comparison to Bacillus subtilis and Escherichia coli cloning hosts.

Quantitative cloning efficiencies for B. megaterium, B. subtilis, and E. coli were compared. Transformation of B. megaterium is less efficient than transformation of B. subtilis or E. coli. The frequency of recombinant clones was equal in E. coli and B. megaterium; both somewhat higher than in B. subtilis. Equivalent average insert sizes were found in B. megaterium and E. coli clones, but significantly smaller inserts were obtained in B. subtilis clones. Clones obtained and propagated in B. megaterium were structurally stable when grown under plasmid selection.