These tools will no longer be maintained as of December 31, 2024. Archived website can be found here. PubMed4Hh GitHub repository can be found here. Contact NLM Customer Service if you have questions.


PUBMED FOR HANDHELDS

Search MEDLINE/PubMed


  • Title: Molecular mechanisms of the irreversible thermal denaturation of guinea-pig liver transglutaminase.
    Author: Nury S, Meunier JC.
    Journal: Biochem J; 1990 Mar 01; 266(2):487-90. PubMed ID: 1969266.
    Abstract:
    When transglutaminase is heated at temperatures above 40 degrees C, it loses its activity according to a two-step mechanism [Nury, Meunier & Mouranche (1989) Eur. J. Biochem. 180, 161-166]: N----X(TD)----D However, the nature of the molecular events responsible for the irreversible denaturation is still unknown. Investigation of the effects of dithiothreitol and 5,5'-dithiobis-2-nitrobenzoate on the kinetics of inactivation, titrations of ammonia released by deamidation and of thiol groups on the native and denatured enzymes and SDS/PAGE rule out the involvement of covalent processes during the denaturation of transglutaminase at 55 degrees C and pH 7. Of the two possible kinds of non-covalent events, i.e. unfolding of the polypeptide chain and aggregation of enzyme molecules, we show that both occur, though only the former process is responsible for the denaturation. The latter process, aggregation, follows the unfolding of the molecules.
    [Abstract] [Full Text] [Related] [New Search]