Restriction digests of the clone give the following sizes (kb): HindIII--2.6; EcoRI--2.6; HindIII/EcoRI--2.6; BglII--1.8, 0.80. An expression vector useful in possibly all E. coli strains containing a functional pho regulatory circuit. The insert must supply the ribosome-binding site. Expression is repressed in the presence of excess inorganic phosphate (>1%) and high concentrations of glucose (>1%). Maximal induction was observed at limiting inorganic phosphate (<0.1 mM) and normal glucose (0.2-0.4%). The order of the major features in this plasmid is: L1 terminator - ugp promoter - EcoRI - MCS - HindIII - rpoC terminator - ori - bla. The nucleotide sequence of the transcription start point before the MCS is GCGAGCATAA AACGCGT. |