Construction of a new host-vector system in Arthrobacter sp. and cloning of the lipase gene.

Arthrobacter sp. strain MIS38 was transformed with a shuttle vector containing the kanamycin resistant gene kan (derived from Tn5) by an electroporation method. This shuttle vector is from Brevibacterium lactofermentum and Escherichia coli, pULRS8. The following optimal condition of electroporation was determined. A square wave pulse of 1 kV/cm electric field strength for 0.5 ms duration yielded 3 x 10(5) transformants/micrograms plasmid DNA. The number of transformants increased with the amount of DNA over the range 0.01-5 micrograms. This host-vector system was then used successfully to clone and express a lipase gene from Arthrobacter sp. strain MIS38 into both Arthrobacter sp. MIS38 and E. coli JM109.