Heme binding to albuminoid proteins is the result of recent evolution.
We hypothesize that the structure of the heme binding site of paralogous albuminoids alpha-fetoprotein and serum albumin has evolved from the ancestor vitamin D binding protein through the 'phylogenetic intermediate' afamin, the most recently discovered albuminoid. Heme binding to plasma proteins should serve not only as a buffer for heme homeostasis, avoiding heme binding to lipoproteins with the consequent oxidative stress, but also for heme transfer to the liver, complementing the function of hemopexin.
Fasano
Mauro
M
Dipartimento di Biologia Strutturale e Funzionale, and Centro di Neuroscienze, Università dell'Insubria, Busto Arsizio, VA, Italy. mauro.fasano@uninsubria.it
Fanali
Gabriella
G
Leboffe
Loris
L
Ascenzi
Paolo
P
D000418:Albumins / Q000235:genetics* / Q000378:metabolism*; D000595:Amino Acid Sequence; D019143:Evolution, Molecular; D006418:Heme / Q000378:metabolism*; D006801:Humans; D008969:Molecular Sequence Data; D011485:Protein Binding
D000418:Albumins; D006418:Heme