Aerobic methane oxidation catalyzed by bacteria is a key step in the global carbon cycle. The process has great importance for the Earth’s climate by reducing the amount of the potent greenhouse gas methane released from habitats such as wetlands and lakes to the atmosphere and by the consumption of atmospheric methane in upland soils. Given their diversity and global importance, methane oxidizing bacteria have not yet been adequately considered in genome sequencing projects.
Crenothrix polyspora has many properties that are highly unusual for aerobic methane-oxidizing bacteria. For example, it possesses a very unusual methane monooxygenase that is significantly different from the version of this key enzyme found in all cultured methanotrophs. In addition, it is capable of assimilating substrates with carbon-carbon bonds. Furthermore, it is the first methane oxidizer with a filamentous morphology and a complex life cycle with several morphologically distinct developmental stages. A genome-based analysis of C. polyspora will thus shed new light on the physiological diversity and evolutionary history of bacterial methane oxidizers. Furthermore, the genome sequence would be an invaluable resource to better understand the regulation of the complex life cycle of this organism and for identifying the cause of its occasional mass developments in drinking water facilities.
Principal Investigators: Michael Wagner (Univ. of Vienna)