Abstract: A safe and versatile recombinant DNA cloning vector having at least two functionally different replication origins selected independently from the group consisting of a replication origin functional in Bacillus subtilis, a replication origin functional in Escherichia coli and a replication origin functional in Pseudomonas aeruginosa, and at least one DNA segment which provides resistance against at least one antibiotic after introduction into susceptible host cells. The origin for replication origin functional in Bacillus subtilis can be a restriction fragment of a plasmid of Gram positive bacteria, and that Escherichia coli or Pseudomonas aeruginosa can be a restriction fragment of a plasmid of Gram negative bacteria, e.g. a restriction fragment of plasmids pMS 140-1 or pMS 71.