Methanococcoides alaskense
A Microbial Biorealm page on the genus Methanococcoides alaskense
Classification
Archaea; Euryarchaeota; Methanomicrobia; Methanosarcinales; methanosarcinaceae; methanococcoides; alaskense
Description and significance
Currently, Methanococcoides alaskense has only been isolated from sediments of Skan Bay, Alaska. Its impacts, if any, on humans or other organisms remain unknown. Similarly, its effects on the environment are also poorly studied. However, it has been suggested that global warming is more pronounced at high latitudes, such as the Artics. Some research has shown an association between the degredation of the Artic permafrost and the intensitifed release of methane, which may represent a potential hazard. Since this species is one of many that produce methane, it could potentially contribute to global warming in the Artics.
Genome structure
Describe the size and content of the genome. How many chromosomes and plasmids? Circular or linear? Other interesting features? What is known about its sequence?
Cell structure, metabolism & life cycle
This species forms colonies that are approximately 1 milimeter in diameter or less, yellow to white in color, circular, and concave. Individual cells are single irregular coccoids that range from 1-2 micrometers in diameter. The cells stain gram negative and are autoflourescent with proeinaceous cell walls. Pili cover the cell surface, but they do not have a flagellum and are non-motile. One strain does, however, have two appendages per cell that appear to be flagella, yet the cells are still non-motile. Some cells contain long rod-like strutures with tubular subunits that are similar to structures that are believed to be the origin of the flagella in Pyrococcus furiosus. Electron-dense regions were also found in many cells, yet the nature of these structures is not known.
They can grow in a temperature range of -2.3-30.6 degrees Celcius, but grow best at 23.6 degrees Celcius. They require a salinity concentration of 0.1M-0.7M and a pH of 6.3-7.5.
Provide a physical and biochemical description of the organism. What kind of organism is it, what does it look like, how is it built, what are its metabolic properties, how can it be identified, what is it's life cycle, &c. In other words, describe the organism from its perspective.
Ecology (including pathogenesis)
Methanococcoides alaskense was isolated from sediment samples from Skan Bay, Alaska. They were collected in sediment 65 meters deep that has a year-round temperature of 1-6 degrees Celcius. The sediment is permanently anoxic below the top centimeter and rich in organic matter from diatoms and kelp. Sulfate is depleted around 45 centimeters below the sediment. The cells use trimethylamine as the only organic catabolic substrate and produce methane.
Describe its habitat, symbiosis, and contributions to environment. If it is a pathogen, how does this organism cause disease? Human, animal, plant hosts? Describe virulence factors and patient symptoms.
Interesting feature
Describe in detail one particularly interesting aspect of your organism or it's affect on humans or the environment.
