Science, Maths & Technology
Oxygen, blood and the body
...Hr) occurs in the bloodstream of certain marine worms. Its higher-order structure has similarities to Hb (which we can consider to be a Mb tetramer), in that Hr is often found as an octameric unit, with a total relative molecular mass of about 8 × 13 500 = 108 000. At its active site, Hr contains two iron atoms. However, despite the ‘haem’ in its name, the protein...