1 Ditzel group, Department of Molecular Medicine, Det Sundhedsvidenskabelige Fakultet, SDU2 Department of Biochemistry and Molecular Biology, Faculty of Science, SDU3 SDU Business, Central Administration, SDU4 unknown5 Department of Biochemistry and Molecular Biology, Faculty of Science, SDU6 SDU Business, Central Administration, SDU
The lac promoter is one of the most commonly used promoters for expression control of recombinant genes in E. coli. In the absence of galactosides, the lac promoter is repressed by its repressor protein LacI. Since the lac promoter is regulated by a repressor, overexpression of LacI is necessary for regulation when the promoter is introduced on a high-copy plasmid. For that purpose, a modified variant of LacI, a LVA-tagged LacI, was submitted to the Registry of Standard Biological Parts and has been used for more than 500 constructs since then. We have found, however, that natural LacI is superior to the LVA-tagged LacI as controller of expression.
A C S Synthetic Biology, 2014, Vol 3, Issue 12, p. 949-52