Heme is ubiquitous in ALL living organism and is even found in strict obligate anaerobes, which cannot survive in the presence of molecular oxygen.
precursors for heme; Heme is a ______
Glycine and succinyl CoA
Heme is a cyclic tetrapyrrole
delta-aminolevulinic acid synthetase (ALAS); controls the _______
Enzyme that synthesizes heme. Controls the rate limiting step of heme synthesis
There is very little free heme in cells because... & consequently.....
heme is poorly soluble in water & consequently heme associates with a ## of apoproteins to form hemoproteins
Examples of common hemoproteins... which occur in both mitochondria & ER?
Hemoglobin, myoglobin, and cytochromes a, b, b5, c and P-450 Cytochromes occur in both mitochondria and in the endoplasmic reticulum
Diseases in humans where there is a genetic defect in one of the heme synthesizing enzymes. Since heme regulates its own synthesis, a slight reduction in heme production results in disregulation of the heme pathway and overproduction of one or more heme precursors!