s=Aminolevulinic Acid Synthetase I. STUDIES IN LIVER HOMOGENATES
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چکیده
6-Aminolevulinic acid synthesis has been demonstrated in both porphyric and normal liver homogenates. A study of the factors which affect &aminolevulinic acid production indicates that the enzyme b-aminolevulinic acid synthetase can be measured in liver homogenates, with use of added glycine and endogenously generated succinyl coenzyme A. 6Aminolevulinic acid production in this system is greater than in the isolated mitochondrial system previously used. The generation of succinyl wenzyme A from endogenous substrates is close to the optimal amount for 8-aminolevulinic acid production in liver homogenates. The determinations of hepatic 6-aminolevulinic acid production in a number of normal species agree well with estimates of the 6-aminolevulinic acid required for heme enzyme synthesis. The effects of factors influencing the synthesis of aminoacetone and 8-aminolevulinic acid in liver homogenates were compared and found to be markedly different.
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