Chapter 17 Microbial Ecology 2 Methane and methanogenesis Rumen microbial ecology Biogeochemical cycles: nitrogen Biogeochemical cycles: sulfur Biogeochemical cycles: iron Microbial leaching Biogeochemical cycles: trace metals and mercury Petroleum and natural gas(methane) biodegradation Biodegradation of xenobiotics Sewage and wastewater micro biology Plant-microorganism interactions: Crown and gall and hairy root Root nodule bacteria and symbiosis with legumes
Chapter 17 Microbial Ecology 2 Methane and methanogenesis Rumen microbial ecology Biogeochemical cycles: nitrogen Biogeochemical cycles: sulfur Biogeochemical cycles: iron Microbial leaching Biogeochemical cycles: trace metals and mercury Petroleum and natural gas (methane) biodegradation Biodegradation of xenobiotics Sewage and wastewater microbiology Plant-microorganism interactions: Crown and gall and hairy root Root nodule bacteria and symbiosis with legumes
Methanogenesis and Syntrophy Methane production is carried out by a group of Archaea, the methanogens, which are obligate anaerobes. 4H2+CO2CH4+2H20 △G0’=-130kJ/ reaction Substrates microbially converted to methane: methanol, formate, methylcaptan(CH3SH), acetate and methylamines
Methanogenesis and Syntrophy Methane production is carried out by a group of Archaea, the methanogens, which are obligate anaerobes: 4 H2 + CO2 CH4 + 2H2O DGo ’= -130 kJ/reaction Substrates microbially converted to methane: methanol, formate, methylcaptan (CH3SH), acetate and methylamines
Complex polymers A noXIc Cellulose other polysaccharides proteins Cellulolytic and Decomposition other hydrolytic Hydrolysis Various groups of Monomers Sugars. fermentative amino acds Fermentative Fermentation bactera anaerobes act Propionate together in the Butyrate H+ cO Succinate conversion of Reproducing Aceto atty.acid anIc acetogensgenesis Fermentation complex orga bacteria (syntrophs) Methano Acetate materials ultimately cate to methane and co2 Methanogenesis CHa
Anoxic Decomposition Various groups of fermentative anaerobes act together in the conversion of complex organic materials ultimately to methane and CO2
Primary fermenters and Secondary fermenters Primary fermenters: consume glucose to a variety of fermentation products(acetate propionate, butyrate, succinate, alcohols hydrogen and CO2 Secondary fermenters: key organisms in the conversion of complex organic materials to methane(espacially the H2-producing fatty acid oxidizing bacteria)
Primary fermenters and Secondary fermenters Primary fermenters: consume glucose to a variety of fermentation products (acetate, propionate, butyrate, succinate, alcohols, hydrogen and CO2. Secondary fermenters: key organisms in the conversion of complex organic materials to methane (espacially the H2-producing fatty acidoxidizing bacteria)
Syntrophy Syntrophy: eating together Syntrophomonas and Syntrophobacter H2 producers, collectively referred to as syntrophs, dependent on syntrophic relationships with other bacteria(in this case, H2-consuming bacteria
Syntrophy Syntrophy: eating together. Syntrophomonas and Syntrophobacter: H2 producers, collectively referred to as syntrophs, dependent on syntrophic relationships with other bacteria (in this case, H2-consuming bacteria)