the plasmid thus extracted has a size of about 5650 bp and is named pste33 the e coli jm109 strain bearing plasmid pste33 was deposited with the above mentioned depository authority on mar 12 1993 under deposit number ferm bp 4451 4 plasmid pste33 was completely digested with restriction endonucleases ecori and hindiii to give a dna fragment of about 3020 bp both ends of the fragment were blunted with t4 dna polymerase and thereafter ligated with t4 dna ligase to give a circulized reaction product b stearothermophilus k1041 strain was transformed with the reaction product the transformation was performed by an electroporation method as shown in biotechnology techniques vol 6 no 1 83 86 1992 the disclosure of which is hereby incorporated by reference herein bacteria treated by the electroporation method were spread on l agar plates 2 0 wt of agar was added to an l medium and solidified containing 10 u03bcg ml of kanamycin and incubated at 48 u00b0 c for 24 hours to give kanamycin resistance transformants from which plasmids were extracted by the conventional method the plasmid thus extracted has a size of about 3020 bp and was named pstk3 b stearothermophilus k1041 strain bearing plasmid.