A fifth pathway of carbon fixation
http://www.sciencemag.org/cgi/content/full/318/5857/1732
There were four major pathways known for microbial carbon dioxide fixation and sequestration. Now, a fifth pathway is described. The current commentary describes the discovery and provides an overview of all the currently known general carbon dioxide capturing mechanisms in biology.
Evolution of carbon dioxide fixation pathways
http://nai.arc.nasa.gov/team/index.cfm?page=projectreports&year=8&teamID=20&projectID=1666This proposal talks about the mechanisms of prokaryotic carbon dioxide fixation which might have evolved at the earliest time in earth’s history.
Carbon fixation in phototrophs
http://www.life.umd.edu/labs/delwiche/PSlife/lectures/CarbonFix.html
These lecture notes provide a good overview of carbon fixation in phototrophic bacteria.
KEGG: Carbon fixation pathways
http://www.genome.ad.jp/dbget-bin/show_pathway?map00710+4.1.1.39
This KEGG metabolic map allows users to see overall metabolic linkages and obtain additional information on metabolic intermediates and enzymes.
Regulation of carbon fixation
http://www.marine.usf.edu/microbiology/regulation.shtml
There are differences in the types of ribulose bisphosphate carboxylases used by different microbes. This probably underlies different ecological niches and needs with respect to metabolic regulation.
Calvin cycle: Ribulose bisphosphate carboxylase
http://www.rpi.edu/dept/bcbp/molbiochem/MBWeb/mb2/part1/dark.htm
Ribulose bisphosphate carboxylase is important in plants and microbes for fixing carbon dioxide by coverting a 5-carbon sugar into two 3-carbon compounds. This website provides an excellent overview of the carbon cycle and the initial enzyme in the pathway.
Calvin cycle
http://www.chem.qmul.ac.uk/iubmb/enzyme/reaction/polysacc/Calvin3.html
This page provides information on the intermediates and enzymes involved in the Calvin cycle for carbon dioxide fixation.
3-Hydroxypropionate cycle
http://krebbing.blogspot.com/2006/12/3-hydroxypropionate-cycle.html
This webpage describes the 3-hydroxypropionate cycle for carbon dioxide fixation. This pathway is known to occur in Chloroflexus and several autotrophic archae.
Reverse tricarboxylic acid cycle
http://krebbing.blogspot.com/2006/12/reverse-tricarboxyclic-acid-cycle.html
The reverse tricarboxylic acid cycle for carbon dioxide fixation is described on this webpage to occur in some green photosynthetic bacteria, hydrogen consuming thermophiles, and sulfate reducing bacteria.
MetaCyc: Incomplete reductive TCA cycle
http://biocyc.org/META/new-image?type=PATHWAY&object=P42-PWY
The metabolic map provided here shows metabolic linkages and provides additional information, via links, on individual enzymes. A good summary of the cycle is also provided.
MetaCyc: Reductive acetyl coenzyme A pathway
http://BioCyc.org/META/NEW-IMAGE?type=PATHWAY&object=CODH-PWY
The metabolic map provided here shows metabolic linkages and provides additional information, via links, on individual enzymes. The major novel enzyme in the pathway is carbon monoxide dehydrogenase/acetyl-CoA synthetase.
MetaCyc: Reductive monocarboxylic acid pathway
http://BioCyc.org/META/NEW-IMAGE?type=PATHWAY&object=PWY-5493
This relatively simple pathway for carbon dioxide fixation occurs largely in Clostridium species.
MetaCyc: Calvin-Benson-Bassham cycle
http://BioCyc.org/META/NEW-IMAGE?type=PATHWAY&object=CALVIN-PWY
The metabolic map provided here shows metabolic linkages and provides additional information, via links, on individual enzymes. A good summary of the cycle is also provided.
UM-BBD: Metahnogenesis pathway map
http://umbbd.msi.umn.edu/meth/meth_map.html
The UM-BBD methanogenesis pathway map shows the key reactions in methane generation from carbon dioxide. While this is not a means for sequestering carbon into an organism, it is a major global reaction for recycling carbon dioxide into organic carbon.
BRENDA: Ribulose bisphosphate carboxylase
http://www.brenda-enzymes.info/php/result_flat.php4?ecno=4.1.1.39
The BRENDA webpage here contains extensive information on ribulose bisphosphate carboxylase and in the many forms of life in which it is found.