Researchers at Imperial College London have found that as bacteria adapt to higher temperatures, they breathe faster and release more carbon, accelerating global climate change, the study was published in the November 12 issue of Nature Communications. Bacteria and geriattas, collectively known as protonuclear organisms, exist on every continent and account for about half of the world’s total.
Most protonuclear organisms breathe the same as humans, consuming energy and releasing carbon dioxide (CO2). The amount of CO2 emitted depends on the rate of breathing of protonuclear organisms, which varies with the outside temperature.
So far, however, the relationship between temperature, respiratory rate and carbon emissions has not been determined. By collecting data analyzing the temperature changes of the breathing rate of 482 protonuclear organisms, the researchers found that most protonuclear organisms increased their carbon emissions more significantly at higher temperatures.
“In the short term, from a few days to a few hours, the metabolism of a single protonuclear organism accelerates and produces more CO2,” said dr. Pawar, the project leader in the Life Sciences Department at Imperial College. But there will be a maximum temperature, and when it reaches that temperature, their metabolism becomes inefficient. In the long run, he points out, these protonuclear communities will evolve more efficiently at higher temperatures over time, further increasing their metabolism and carbon emissions. As a result, rising temperatures will enable many protonuclear communities to operate more effectively in the short and long term, thereby contributing more to global carbon emissions and the resulting temperature increases.
The researchers compiled the reactions of protonuclear organisms from around the world and under different conditions to temperature changes, from Antarctic saltwater lakes below 0c to hot pools above 120C. They found that protonuclear organisms, which typically react strongly to temperature changes in the medium temperature range (below 45 degrees C), increased breathing in both the short term (a few days to weeks) and the long term (months to years). There is no such reaction in the higher temperature range (over 45 degrees C), but because they are active at such high temperatures from the outset, they are less likely to be affected by climate change. The short-term response of mid-warm nucleonuclears to climate change is larger than that of eukaryotes (cell-more complex organisms).
Thomas Smith, lead author of the study and a doctoral student in the Life Sciences Department at Imperial College, said: “Most current climate models assume that all organisms respond to temperature at the same rate of breath, but our study suggests that bacteria and ancient bacteria may deviate from the ‘global average’.” He believes that given that these microbes may be important contributors to total respiratory and carbon emissions in many ecosystems, climate models should take full account of their more sensitive to temperature changes in the short and long term, which will help to create more accurate models of future climate change.