Enzymology of the pathway for ATP production by arginine breakdown

摘要: In cells, the breakdown of arginine to ornithine and ammonium ion plus carbon dioxide is coupled generation metabolic energy in form ATP. The pathway minimally composed deiminase, transcarbamoylase, carbamate kinase, an arginine/ornithine antiporter; ammonia most likely diffuse passively across membrane. genes for enzymes transporter have been cloned expressed, proteins purified from Lactococcus lactis IL1403 incorporated into lipid vesicles sustained production Here, we study kinetic parameters biochemical properties individual antiporter, determine how physicochemical conditions, effector composition, concentration affect enzymes. We report KM VMAX values catalysis native oligomeric state all proteins, measured effect intermediates, pH, temperature, freeze–thaw cycles, salts on activity cytosolic also present data protein-to-lipid ratio composition dependence antiporter.