May be involved in the biosynthesis of heme A. Porphyrin-containing compound metabolism; heme A biosynthesis; heme A from heme O: step 1/1. Predominantly found in tissues characterized by high rates of oxidative phosphorylation (OxPhos), including muscle, heart, and brain. The disease is caused by variants affecting the gene represented in this entry. Belongs to the COX15/CtaA family.