Nucleic Acids Research, 1977, Vol. 4, No. 3 723-737
© 1977
Articles |
Studies on gene control regions. III. Binding of synthetic and modified synthetic lac operator DNAs to lactose repressor*
Department of Chemistry, University of Colorado Boulder, CO 80309, USA
Received February 3, 1977.
Chemically synthesized lactose operator DNA was tested for binding with lactose repressor protein. These operator DNAs were found to (1) bind specifically to lactose SQ repressor as measured by release of binding with the inducing ligand isopropyl-ß-D-thiogalactoside, (2) have dissociation half-lives of 37 seconds (21 base-paired duplex) and 46 seconds (26 base-paired duplex) and (3) have dissociation half-lives with x86 repressor of 9 minutes (21 base-paired duplex) and 18 minutes (26 base paired duplex). Modified operators containing 5-bromodeoxyuridine and deoxyuridine at specific sites were also prepared. These analogs bound both repressors about as tightly as the wild type sequence.
*This is paper III in a series on "Studies on Gene Control Regions". Paper II is ref. 3. This work was supported by grants from the National Institutes of Health (GM 21120 and GM 21644), a Cottrell Research Grant from Research Corporation, the National Science Foundation (PCM 76-01489), a Biomedical Sciences Support Grant from the National Institutes of Health to the University of Colorado, a National Science Foundation equipment grant (BMS 75-14541) and the University of Colorado. M.H.C. was supported by a Career Development Award from the National Institutes of Health (1 K04 GM 00076).