Halflife of lac repressor-operator [RO] complex

Value 19 min Range: ±4 min
Organism Bacteria Escherichia coli
Reference Riggs AD, Bourgeois S, Cohn M. The lac repressor-operator interaction. 3. Kinetic studies. J Mol Biol. 1970 Nov 1453(3):401-17 abstract, p.404 4th paragraph & p.413 2nd paragraphPubMed ID4924006
Method Abstract p.401: "A sensitive membrane filter assay for the lac repressor-operator complex has been used to study the kinetics of repressor and operator interaction."
Comments Abstract: "The rate of dissociation of the complex is very slow and follows first-order kinetics with a half-life of 19 minutes in [investigators'] standard buffer (0.05 M ionic strength)." P.404 4th paragraph: "In Figure 2, [investigators] have concentrated on the initial linear portion of the curve, and it can be seen that first-order kinetics are followed for at least 30 minutes, with the halflife being close to 19 minutes...In [their] standard BB buffer at 24°C the half-life is 19±4 minutes, where the range is the standard deviation for 18 experiments." P.402 4th paragraph: "BB buffer contains: 0.01 M-magnesium acetate, 0.01 M-KCl, 10^-4 M-EDTA, 10^-4M-dithiothreitol, 5% dimethyl sulfoxide, 0.01 M-Tris-HCl, pH 7.4 at 24˚C, and 50 µg bovine serum albumin/ml."
Entered by Uri M
ID 114338