Activities of delta-aminolevulinic acid (ALA) synthase and ALA dehydratase, the first and the second enzymes of the heme biosynthetic pathway, were determined in erythroid colonies derived from normal human bone marrow in culture. ALA synthase and ALA dehydratase were induced when normal human bone marrow cells were incubated in the presence of erythropoietin (Ep) in culture, and the extent of induction of ALA synthase as well as ALA dehydratase was dependent on Ep concentrations and culture periods. Both ALA synthase and ALA dehydratase were increased in cultured erythroid cells before the appearance of morphologically recognizable hemoglobinized colonies, corroborating the sequential induction of heme biosynthetic pathway enzymes in human bone marrow erythroid cells.

中文翻译：

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在正常人骨髓培养物中诱导δ-氨基乙酰丙酸合酶和δ-氨基乙酰丙酸脱水酶。

确定了血红素生物合成途径的第一种和第二种酶δ-氨基乙酰丙酸（ALA）合酶和ALA脱水酶的活性。当在培养物中促红细胞生成素（Ep）的存在下孵育正常人骨髓细胞时，会诱导ALA合酶和ALA脱水酶，并且ALA合酶和ALA脱水酶的诱导程度取决于Ep浓度和培养时间。在形态学上可识别的血红蛋白菌落出现之前，培养的红细胞中的ALA合酶和ALA脱水酶均增加，从而证实了人骨髓红细胞中血红素生物合成途径酶的顺序诱导。