Heme hijacker
16 Nov 2011 by Evoluted New Media
Heme – one of the key pigments of life – can be synthesised via a new, unusual and unexpected chemical process say researchers from the University of Kent. Researchers discovered that heme – the component that gives blood its colour and allows red blood cells to carry oxygen around the body – can be made from a related molecule called siroheme in an unexpected way.
By studying how heme is synthesised in Archaea – a unique type of single-celled organism – researchers discovered that at a molecular level, siroheme is hijacked and bought into the chemical process that synthesises heme.
In molecular and cellular biochemistry, this is a very rare example of where one prosthetic group – the siroheme – is cannibalised for the synthesis of another.
“This is a very important piece of basic science that offers an explanation as to how biochemical pathways evolve and become more complex,” said Professor Martin Warren, head of the school of biosciences at Kent.
“Moreover, we have learnt some new concepts about how chemistry can be used to change the shape and the character of larger molecules, which can be applied for the development of new compounds.
Warren likened the importance and scale of this discovery as being similar to the transformation of the first electronic calculators into the modern mobile phone.
The project – which also involved researchers from the University of Oxford and the Instituto de Tecnologia Química e Biológica in Portugal – involved studying a number of very unusual biochemical reactions in a glove-box completely devoid of oxygen. It was only under these unique conditions – and with the help of the school’s new nuclear magnetic resonance spectrometer – that researchers were able to observe the reactions taking place.
Heme is best known for the role it performs when it’s attached to a large protein called globin to yield haemoglobin. It’s this role as a prosthetic group that allows both heme and globin to perform their functions.
Molecular hijacking of siroheme for the syntheseis of heme and d1 heme
