Methanopyrus

Methanopyrus is a genus of the Methanopyraceae. Methanopyrus is a genus of methanogen, with a single described species, M. kandleri. It is a rod-shaped hyperthermophile, discovered on the wall of a black smoker from the Gulf of California at a depth of 2,000 m, at temperatures of 84–110 °C. Strain 116 was discovered in black smoker fluid of the Kairei hydrothermal field; it can survive and reproduce at 122 °C. M. kandleri also requires a high ionic concentration (>1 M) in order for growth and cellular activity. Due to the species' high resilience and extreme environment, M. kandleri is also classified as an extremophile. It lives in a hydrogen-carbon dioxide rich environment, and like other methanogens reduces the latter to methane. It is placed among the Euryarchaeota, in its own class. Methanopyrus kandleri is a rod-shaped methanogen with an approximate length of 2-14 μm and diameter of 0.5 μm. The cellular membrane of M. kandleri is unique as it consists of terpenoid lipids, believed to be one of the most primitive lipids and a predecessor to phytanyl di-ethers found in later archaea. Terpenoid lipids are a group of lipids containing cholesterol, hopanoids, carotenoid, phytane, and bisphytane. Although terpenoids are the main component of the membrane in M. kandleri, they are more of a supporting structure in eukaryote and bacteria. M. kandleri is motile via polar flagella tufts. Methanopyrus kandleri has a high concentration of cyclic 2,3-diphosphoglycerate. This compound is often found in hyperthermophile, helping to prevent protein denaturation in high temperatures. The increased concentration of cyclic 2,3-diphosphoglycerate protects the methanogen, helping it survive in an environment that many other organisms could not. Beyond this compound to help protect the proteins, M. kandleri also has a high salt concentration inside its membrane. This increased concentration of salt helps with enzyme stability and promotes activity of the enzymes at higher temperatures. As a methanogen, M.