Termite guts: the world's smallest bioreactors

Termite hindguts have long been considered simply to be anoxic fermentors, similar to the rumen of cattle. This concept was challenged by recent investigations employing microsensor techniques, which demonstrated that the metabolic activity of the gut microbiota maintains steep oxygen and hydrogen gradients within the gut lumen. Only the centre of the dilated gut regions is rendered anoxic, yet methanogens form a major hydrogen sink in the microoxic gut periphery. In the extremely alkaline hindguts of soil-feeding termites (pH > 12), lignocellulose-derived soil organic matter is subject to a sequential incubation at varying pH and oxygen levels.

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