S P Manly, K S Matthews, J M Sturtevant
Index: Biochemistry 24(15) , 3842-6, (1985)
Full Text: HTML
The thermal denaturation of the core protein of lac repressor was studied alone and in the presence of the inducer isopropyl beta-D-thiogalactoside (IPTG) and the antiinducer o-nitrophenyl beta-D-fucoside (ONPF) by means of high-sensitivity differential scanning calorimetry. The denaturation that takes place at about 65 degrees C is apparently irreversible; i.e., a rescan of a previously scanned sample of protein solution shows no denaturational endotherm. Despite this irreversibility, the denaturation appeared to follow quantitatively the dictates of equilibrium thermodynamics as embodied in the van't Hoff equation. The results obtained indicate clearly that the tetrameric protein dissociates to monomers during denaturation and that the ligands are not dissociated until denaturation takes place. The enthalpy of denaturation of the protein is 4.57 +/- 0.25 cal g-1 and is independent of temperature. The enthalpies of dissociation of IPTG and ONPF at the denaturation temperature are very large, 37 and 42 kcal (mol of ligand)-1, respectively.
Structure | Name/CAS No. | Molecular Formula | Articles |
---|---|---|---|
![]() |
2-nitrophenyl β-D-fucoside
CAS:1154-94-5 |
C12H15NO7 |
A closer view of the conformation of the Lac repressor bound...
2000-03-01 [Nat. Struct. Biol. 7(3) , 209-14, (2000)] |
Escherichia coli lac repressor-lac operator interaction and ...
1997-01-10 [J. Mol. Biol. 265(1) , 1-7, (1997)] |
Using networks to identify fine structural differences betwe...
2004-08-31 [Biochemistry 43(34) , 10886-95, (2004)] |
Altering residues N125 and D149 impacts sugar effector bindi...
2011-10-25 [Biochemistry 50(42) , 9002-13, (2011)] |
Ligand interactions with lactose repressor protein and the r...
2007-03-01 [Biophys. Chem. 126(1-3) , 94-105, (2007)] |
Home | MSDS/SDS Database Search | Journals | Product Classification | Biologically Active Compounds | Selling Leads | About Us | Disclaimer
Copyright © 2024 ChemSrc All Rights Reserved