Testing polyols' compatibility with Gibbs energy of stabilization of proteins under conditions in which they behave as compatible osmolytes.
It is generally believed that compatible osmolytes stabilize proteins by shifting the denaturation equilibrium, native state <--> denatured state toward the left. We show here that if osmolytes are compatible with the functional activity of the protein at a given pH and temperature, they should not significantly perturb this denaturation equilibrium under the same experimental conditions. This conclusion was reached from the measurements of the activity parameters (K(m) and k(cat)) and guanidinium chloride-induced denaturations of lysozyme and ribonuclease-A in the presence of five polyols (sorbitol, glycerol, mannitol, xylitol and adonitol) at pH 7.0 and 25 degrees C.
Haque
Inamul
I
Department of Biosciences, Jamia Millia Islamia, Jamia Nagar, New Delhi 110 025, India.
Singh
Rajendrakumar
R
Ahmad
Faizan
F
Moosavi-Movahedi
Ali Akbar
AA
D000818:Animals; D001703:Biophysics / Q000379:methods; D002645:Chickens; D002942:Circular Dichroism; D004305:Dose-Response Relationship, Drug; D004529:Egg White; D005990:Glycerol / Q000737:chemistry; D019791:Guanidine / Q000737:chemistry / Q000494:pharmacology; D006863:Hydrogen-Ion Concentration; D007700:Kinetics; D008353:Mannitol / Q000737:chemistry; D009113:Muramidase / Q000737:chemistry; D009995:Osmosis; D011108:Polymers / Q000737:chemistry*; D011485:Protein Binding; D011489:Protein Denaturation; D012255:Ribitol / Q000737:chemistry; D012259:Ribonuclease, Pancreatic / Q000737:chemistry; D013012:Sorbitol / Q000737:chemistry; D013696:Temperature; D013816:Thermodynamics; D014466:Ultraviolet Rays; D014993:Xylitol / Q000737:chemistry
D011108:Polymers; C024617:polyol; D008353:Mannitol; D012255:Ribitol; D013012:Sorbitol; D012259:Ribonuclease, Pancreatic; D009113:Muramidase; D019791:Guanidine; D005990:Glycerol; D014993:Xylitol