Search For The Biochemical Basis Of Biotin Dependent Multiple Carboxylase Deficiencies - Determination Of Biotin Activation In Cultured Fibroblasts

The activation step of biotin into biotinyl-AMP, which precedes the fixation of the prosthetic group on the apocarboxylases, has been examined in cultured fibroblasts from patients with biotin-dependent multiple carboxylase deficiencies. Two kinds of patients were tested, those with a defective holocarboxylase synthetase activity and those with a low level of the vitamin in the plasma. In both cases, the activation step of biotin was found to be very close to normal values.