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A molecule containing four pyrrole nuclei; for example, porphyrin.
Farlex Partner Medical Dictionary © Farlex 2012
References in periodicals archive ?
Grimm, "Cytokinin effects on tetrapyrrole biosynthesis and photosynthetic activity in barley seedlings," Planta, vol.
Geoporphyrins are molecules that have characteristic tetrapyrrole macrocyclic structures substituted with various alkyl chains.
In hemoglobin, the iron present in ferrous form ([Fe.sup.2+]) at the center of the tetrapyrrole core (protoporphyrin IX), forming the heme nucleus.
Tetrapyrrole Extraction and Preparation of HPLC Samples.
Intermittent hypoxia can affect the stability of the bond of iron to the tetrapyrrole ring of protoporphyrin, thus releasing iron inside the erythrocytes, along with hemoglobin autoxidation [80].
Porphyrins are tetrapyrrole macrocyclic compounds playing a transcendental role in nature as one of the principal components of molecules such as (i) chlorophyll, (ii) the heme group in blood and cytochromes and (iii) cyanocobalamin (Vitamin [B.sub.12]) [1-3].
Evaluation of in vivo biological activities of tetrapyrrole ethanolamides as novel anticancer agents.
A porphyrin molecule consists of heterocyclic tetrapyrrole unit, called porphine, and meso-substituents.
In any case we must break the porphyrin-related tetrapyrrole ring systems that chelate and capture the industrially important metals.