Methanogens for human welfare: More boon than bane

Microorganisms that produce methane as an end product of their energy-generating metabolism are known as methanogens. They represent phylum Euryarchaeota and are one of the most diverse groups of archaea. The ability of methanogens to utilize carbon dioxide and other by-products of bacterial metabolism as a ‘C’ and ‘E’ source and eventually convert them into methane has become the focus of recent research. Methanogens make significant contribution to global warming through emission of methane, the greenhouse gas. Biogenic methane in the form of methane hydrate trapped in subsurface sediments amounts to massive deposits of methane. Methane emissions from such deposits as a consequence of tectonic shifts can contribute to global warming through creation of ozone holes. Methane hydrates on the other hand can also serve as an untapped source of energy. Methane, if recovered, can be used as fuel, for heating, electricity/energy production and also for the synthesis of valuable chemicals. Methanogenic waste treatment of high-strength industrial waste has made the effluent treatment a cost-efficient process rather than a cost-intensive one. Although emissions of methane have adverse impact on the environment, the desirable use of methanogens for reducing environmental pollution, renewable energy generation and the synthesis of valuable chemicals has made methanogens in the environment a ‘boon rather than bane’.