Restriction digests of the clone give the following sizes (kb): EcoRI--2.5, 2.4; HindIII--2.45, 2.3; SalI--4.9. Because resistance levels may vary, it is important to determine the proper antibiotic concentration for each strain or isolate. One of a series (ATCC 37653 through 37657) of vectors for in vitro mutagenesis (via the omega interposon) of gram-negative genera. pHP45:omega was cut with BssHII + SphI (removing the spcR/strR gene) and the ends were made blunt. This was ligated to a blunt-ended 1.4 kb HindIII/AvaI fragment of pBR322 containing the tetracycline resistance gene. |
