Heme biosynthesis is the process by which the body produces heme, an essential component of hemoglobin, myoglobin, and various enzymes. This process occurs mainly in the liver and bone marrow, starting with the precursor molecule glycine and succinyl-CoA. Through a series of enzymatic reactions, these precursors are converted into porphyrin, which is then transformed into heme. The biosynthesis pathway involves eight key steps, each catalyzed by specific enzymes. Deficiencies or mutations in these enzymes can lead to disorders such as porphyrias, which are characterized by the accumulation of porphyrins and their precursors, causing various health issues.