Bacteria detect gas

Press, 26 September 1988, Page 20

Bacteria detect gas

BRITISH scientists have discovered a rare group of bacteria which can detect dangerous carbon monoxide gas and convert it into harmless carbon dioxide. The discovery has been made in north-east England by Dr Edwin Williams of Newcastle University and Dr John Colby of Sunderland Polytechnic. Carbon monoxide is not only explosive and extremely toxic, but its hazard is increased due to the difficulty of detection: it is colourless, odourless and tasteless. “The gas binds to the oxygencarrying molecules in red blood cells, preventing the transportation of oxygen around the body,” explained Dr Williams. “In extreme cases, such starvation of

oxygen can lead to tissue damage, gangrene and amputation.” Carbon monoxide is the biggest man-made atmospheric pollutant. It is a problem in coal mines and other industrial environments. The group of rare bacteria discovered in Newcastle have unique biochemical properties which enable them to be very good at detecting small concentrations of carbon monoxide and oxidising it to carbon dioxide. They produce enzymes called carbon monoxide oxidases which carry out the oxidation process. This results, in the production of a small electrical current which the bacteria use as a source of energy for all their cell processes. The current also detoxifies the environment in which

they live. Of particular significance is the fact that the enzymes are specific to carbon monoxide only. They can be produced very cheaply through genetic engineering making them potentially ideal for use in biosensors in coal mines, steelworks, blast furnaces, tunnels and nuclear submarines. The small electrical current produced by the oxidation could be coupled either to a chemical dye which would change colour in a hazardous environment, or linked to the latest microchip technology to produce, a very accurate and sensitive alarm device, said Dr Williams. London Press Service