Scientists have discovered how living organisms including humans avoid poisoning from carbon monoxide generated by natural cell processes.
Carbon monoxide is a toxic gas that can prove fatal at high concentrations; the gas is most commonly associated with faulty domestic heating systems and car fumes, and is often referred to as 'the silent killer'.
But carbon monoxide chemical symbol CO is also produced within our bodies through the normal activity of cells. Scientists have long wondered how organisms manage to control this internal carbon monoxide production so that it does no harm.
University of Manchester researchers, working with colleagues at the University of Liverpool and Eastern Oregon University, have now identified the mechanism whereby cells protect themselves from the toxic effects of the gas at these lower concentrations.
Carbon monoxide molecules should be able to readily bind with protein molecules found in blood cells, known as haemproteins. When they do, for instance during high concentration exposure from inhaling, they impair normal cellular functions, such as oxygen transportation, cell signaling and energy conversion. It is this that causes the fatal effects of carbon monoxide poisoning.
The haemproteins provide an ideal 'fit' for the CO molecules, like a hand fitting a glove, so the natural production of the gas, even at low concentrations, should in theory bind to the haemproteins and poison the organism, except it doesn't.
"Toxic carbon monoxide is generated naturally by chemical metabolic reactions in cells but we have shown how organisms avoid poisoning by these low concentrations of 'natural' carbon monoxide," said Professor Nigel Scrutton, who is based in the Manchester Interdisciplinary Biocentre within the Faculty of Life Sciences.
"Our work identifies a mechanism by which haemproteins are protected from carbon monoxide poisoning at low, physiological concentratio
|Contact: Aeron Haworth|
University of Manchester