HEAVY-METAL RESISTANT ARTHROBACTER SP - A TOOL FOR STUDYING CONJUGATIONAL PLASMID TRANSFER BETWEEN GRAM-NEGATIVE AND GRAM-POSITIVE BACTERIA

The role of two heavy metal-resistant strains of the Gram-positive gen us Arthrobacter sp. as a tool in studying conjugational plasmid transf er between Gram-positive and Gram-negative bacteria is described. The high nickel resistance and the cobalt resistance of Arthrobacter sp. s train RM1/6 could be transferred to Arthrobacter sp. strain WS14. IncQ plasmids (pKT240, pKT240::czc, pML10) could be mobilized from E. coli into Arthrobacter spp. strains; antibiotic (Km, Ap, Tc)(1)) and heavy metal (Go) resistance genes were expressed in the recipient strains. IncQ plasmid pKT240 could be mobilized between Arthrobacter spp. strai ns. IncP plasmid RP4::Tn4371 was transferred from A. eutrophus to Arth robacter sp., RP4-mediated antibiotic resistance to Km was expressed i n the recipient strain.