Barring few bacteria, the majority of these organisms are so small that they are invisible to the naked human eye, but don’t go by their size! We all know, when it comes to making a huge impact, bacteria can turn our lives topsy-turvy. Climate change is no exception. Skyrocketing emission of greenhouse gases into the atmosphere by human activities has risen average global temperature. This has presented a multitude of challenges in front of us. One of the challenges, scientists warn, can come from bacteria which — in spite of being small — can wreak havoc on climate change if the climate change is not stalled! Yes, you read it right, climate change will trigger bacteria to adapt in such a way that will worsen climate change more.
Bacteria are ubiquitous and in a very large number; they make up around 20 to 50 per cent of the total biomass of our planet. The rising temperature of the earth is making them respond in a rather unfavourable way — thanks to their highly adaptive nature! Just like humans, for energy, bacteria, as well, undergo the process of respiration wherein they take in air and release carbon dioxide gas into the atmosphere. However, scientists say, these bacteria try to adapt themselves in hotter temperature by increasing their rate of respiration which results in more release of carbon dioxide into the atmosphere.
This increased CO2 — which is a greenhouse gas — can potentially contribute more to climate change. The high adaptive capacity of bacteria creates a positive feedback loop where hotter temperature due to climate change makes them produce more CO2 which in turn fuels climate change. In an experiment done on prokaryotes including archaea and bacteria, the rate of c02 emissions increased with rising temperature. It is worth mentioning that these adaptations were only observed in bacteria living under 45° Celsius and little to no response was observed in bacteria living over 45° Celsius.
These findings are worrying, especially when we have not yet found out effective solutions and implemented measures to mitigate the emission of greenhouse gases; the climate change will only intensify and with that their metabolism will boost increasing the rate of CO2 production. Collectively, bacteria can release a lot of CO2; it is estimated that CO2 emission by these bacteria may increase by 5 to 10 per cent in response to climate change. However, there are some strains of bacteria, specifically of Escherichia coli which can help us in fighting against climate change. Some of these strains have been used to create biofuels and other chemicals using sugar. Scientists have now discovered a way where these bacteria can feed on CO2 instead of sugar and can produce biofuels. This discovery, if becomes commercially viable and feasible, can help convert atmospheric carbon dioxide to biomass. The biofuel is known to be one of the cleanest sources of energy and unlike energy produced by combustion of fossil fuels, the biofuels do not release any greenhouse gases and hence, do not contribute to climate change. It indeed gives a glimmer of hope for our fight against global warming.