作者: Arthur D. Riggs , Hiromi Suzuki , Suzanne Bourgeois
DOI: 10.1016/0022-2836(70)90219-6
关键词: Operator (biology) 、 Equilibrium constant 、 Inducer 、 Ionic strength 、 Repressor 、 Biochemistry 、 Guanine 、 Chemistry 、 Lac repressor 、 DNA 、 Biophysics
摘要: Abstract A membrane filter technique for detecting lac repressor-operator complexes is discussed and it shown that this method assays present in solution prior to filtering. The sensitive (10−16 mole), accurate, suitable physical chemical experiments. Our results are consistent with the idea only one repressor binds per operator. We report on equilibrium constant (1 × 10−13 m our standard buffer) effect of several reaction conditions parameter. In particular, binding very ionic strength, logarithm being proportional square root strength. Evidence subunits a preferential loss DNA activity compared inducer (isopropyl-thiogalactoside) presented. Methods determining concentration capable described. Actinomycin D inhibits binding, suggesting there at least guanine or near also competition assay unlabeled operator show does not bind denatured but will following renaturation DNA. Native Escherichia coli without region compete even when 300-fold weight excess (10 μg/ml.) used. thus extremely specific.