part of part of has part has part characteristic of inheres in has modifier porphyrins Abnormal circulating porphyrin concentration 2009-09-15T09:53:11Z An abnormality in the synthesis or catabolism of heme. Heme is composed of ferrous iron and protoporphyrin IX and is an essential molecule as the prosthetic group of hemeproteins such as hemoglobin, myoglobin, mitochondrial and microsomal cytochromes. UMLS:C4023814 HP:0010472 Abnormal circulating organic compound concentration amount abnormal blood