BIOL 2051 Lecture Notes - Lecture 19: Halobacterium Salinarum, Thermoplasmatales, Euryarchaeota
Document Summary
Widest range of environments: ph 0, high pressure, anaerobic. Unique biochemistry: methane production, no peptidoglycan, have pseudoglycan, differences in glycolytic pathways, differences in lipids and membranes. 4 phyla of archaea- (2 major, 2 minor) Require at least 9% nacl for growth- most require 12-23% Common in salt lakes and salterns (ponds used to prepare solar salt by evaporation of sea water) To prevent water loss in hypertonic environment. Pump inorganic ions (k+, potassium) into the cell. Make or concentrate an organic soluble in cell. Some extreme halophiles use light to produce energy. Don"t have chlorophyll, have protein called bacteriorhodopsin (red color) Light energy is used to pump protons to outside surface of cell membrane and generate h+ or na+ gradient. Atpase uses this gradient to form atp: methanogens. Release 100 million tons of methane into atmosphere each year. Gastrointestinal tract of animals- human large intestine. Rumen- 10-20% of total methane emitted to atmosphere originates in rumen.
