REGULATORY FUNCTION OF PROTEIN-X IN THE PYRUVATE-DEHYDROGENASE COMPLEX

A theoretical analysis of the regulatory role of protein X, a componen t of pyruvate dehydrogenase complex (PDC), was carried out. Basing on Literature data, a kinetic model was formulated to describe structural and functional interactions between protein X and other components of the complex. Computer analysis of the model revealed the crucial role of protein X in PDC functioning and regulation, and indicated a possi bility of switching between two major reaction pathways. It was demons trated that product (acetyl-CoA) formation rate can abruptly become in dependent of substrate (pyruvate) concentration when it reaches a cert ain level. The significance of the novel type of PDC regulation for st abilization of energy metabolism is discussed.