Artificial and natural thermostabilization of subunit enzymes. Do they have similar mechanism?
Rabbit skeletal muscle glyceraldehyde-3-phosphate dehydrogenase was stabilized by intramolecular intersubunit crosslinking with diimidoesters. Half-inactivation temperature for optimal cross-linker-treated enzyme preparation increased by 11 degrees C. Stabilization effect correlated with the content of crosslinked fractions in enzyme preparation, as proved by SDS gel-electrophoresis. It is proposed that artificial crosslinks stabilize the enzyme in a similar fashion to salt bridges in the thermophilic bacteria enzymes, i.e. preventing dissociation into inactive subunits.
D000818:Animals; D055598:Chemical Phenomena; D002621:Chemistry; D003432:Cross-Linking Reagents; D004798:Enzymes; D001411:Geobacillus stearothermophilus / Q000201:enzymology; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases; D006358:Hot Temperature; D066298:In Vitro Techniques; D009132:Muscles / Q000201:enzymology; D011489:Protein Denaturation; D011817:Rabbits; D013816:Thermodynamics; D013824:Thermus / Q000201:enzymology; D013997:Time Factors
D003432:Cross-Linking Reagents; D004798:Enzymes; D005987:Glyceraldehyde-3-Phosphate Dehydrogenases