The microorganism Methanosarcina acetivorans lives off everything it can metabolize into methane. How it finds its sources of energy, is not yet clear. Scientists at the Ruhr-Universitt Bochum together with colleagues from Dresden, Frankfurt, Muelheim and the USA have identified a protein that might act as a "food sensor". They characterized the molecule in detail and found both similarities and differences to the system that is responsible for the search for food in bacteria. The team reports in the Journal of Biological Chemistry.
MsmS has a different function to that thought
The protein MsmS has so far only been studied from a bioinformatics point of view. Computer of its gene sequence had predicted that it might be a phytochrome, i.e. a red light sensor. Using spectroscopic methods, the research team of the current study have refuted this theory. MsmS has a heme cofactor, like haemoglobin in red blood cells, and can, among other things, bind the substance dimethyl sulphide. This is one of the energy sources of Methanosarcina acetivorans. MsmS might thus serve the microorganism as a sensor to directly or indirectly detect this energy source. In genetic studies, the scientists also found evidence that MsmS regulates systems which are important for the exploitation of dimethyl sulphide.
Archaea: flexible "eaters"
Methanosarcina acetivorans belongs to the Archaea which constitute the third domain of life, alongside Bacteria and Eukarya; the term Eukarya comprising all living organisms with a cell nucleus. Many of them are adapted to extreme conditions or are able to use unusual energy sources. Among the organisms that live from methane production, the so-called methanogenic organisms, M. acetivorans is one of the most flexible when it comes to the choice of food sources. It converts many different molecules into methane, and thus produces energy. How M. acetivorans detec
|Contact: Dr. Nicole Frankenberg-Dinkel|