In human beings, PEP carboxykinase is equally distributed in both location and thus either oxaloacetate or PEP formed inside the matrix of mitochondria must be transported out into the cytosol. The transport of oxaloacetate requires shuttle system. It is converted either into malate catalyzed by malate dehydrogenase or into aspartate catalyzed by aspartate aminotransferase in the matrix before being transported out of the matrix into the cytosol through their respective transporter. In the cytosol, malate or aspartate is converted back into the oxaloacetate catalyzed by cytosolic isoenzymes and then oxaloacetate is converted into the phosphoenolpyruvate catalyzed by PEP carboxykinase.
An excellent text. It presents Biochemistry with frequent references to organic chemistry and biochemical logic. Highly reccommended for students of Biochemistry, Chemistry and Pharmaceutical Sciences. Biochemistry, Stryer A widely used classical text, frequently updated and re-issued. Textbook of Biochemistry with Clinical Correlations, Thomas Devlin Strongly advised to students in Nursing, Medicine, Dentistry, etc. Plenty of examples of application of biochemical knowledge to clinical cases. Principles of Biochemistry, Lehninger A widely used classical text, frequently updated and re-issued. visitas desde 4 de Janeiro de 2002