heme synthesis
protoporphyrin
porphyrin biosynthesis
biochemical intermediate
A: What is the role of protoheme in this reaction?
A：在这种反应中，protoheme 的作用是什么？
B: It serves as a precursor to the heme molecule.
B：它是血红素分子的前体。
1) 血红素的前体物质
2) 卟啉合成的中间产物
1. 血红素前体
noun
1. A substance that is an intermediate or precursor in the biosynthesis of heme.