View source for Biology:Methanogens in digestive tract of ruminants

Methanogens are a group of microorganisms that produce [[Chemistry:Methane|methane]] as a byproduct of their metabolism. They play an important role in the digestive system of ruminants. The digestive tract of ruminants contains four major parts: [[Biology:Rumen|rumen]], [[Biology:Reticulum (anatomy)|reticulum]], [[Biology:Omasum|omasum]] and [[Biology:Abomasum|abomasum]]. The food with saliva first passes to the rumen for breaking into smaller particles and then moves to the reticulum, where the food is broken into further smaller particles. Any indigestible particles are sent back to the rumen for rechewing. The majority of anaerobic microbes assisting the cellulose breakdown occupy the rumen and initiate the fermentation process. The animal absorbs the fatty acids, vitamins and nutrient content on passing the partially digested food from the rumen to the omasum. This decreases the pH level and initiates the release of enzymes for further breakdown of the food which later passes to the abomasum to absorb remaining nutrients before excretion. This process takes about 9–12 hours.
Some of the microbes in the ruminant digestive system are:

*''[[Biology:Fibrobacter succinogenes|Fibrobacter (Bacteroides) succinogenes]]'' is a gram negative, cellulolytic and amylolytic methanogen that produces formates, acetates and succinates.
*''Ruminococcus albus'' is a cellulolytic, xylanolytic bacterium producing ethanol, hydrogen, carbon dioxide, formates and acetates.
*''Ruminococcus flavefaciens''<ref>{{cite journal |doi=10.1128/JB.00143-07 |pmid=17468247 |pmc=1913464 |title=A Novel Cell Surface-Anchored Cellulose-Binding Protein Encoded by the sca Gene Cluster of Ruminococcus flavefaciens |journal=Journal of Bacteriology |volume=189 |issue=13 |pages=4774–83 |year=2007 |last1=Rincon |first1=M. T. |last2=Cepeljnik |first2=T. |last3=Martin |first3=J. C. |last4=Barak |first4=Y. |last5=Lamed |first5=R. |last6=Bayer |first6=E. A. |last7=Flint |first7=H. J. }}</ref> is a cellulolytic, xylanolytic bacteria producing formates, acetates, hydrogen and succinates.
*''Butyrivibrio fibrisolvens''<ref>{{cite journal |pmid=3524460 |pmc=203391 |year=1986 |author1=Cotta |first1=M. A. |title=Proteolytic activity of the ruminal bacterium Butyrivibrio fibrisolvens |journal=Applied and Environmental Microbiology |volume=52 |issue=1 |pages=51–8 |last2=Hespell |first2=R. B. }}</ref> is a proteolytic, cellulolytic, xylanolytic microbe producing lactate, butyrate, ethanol, hydrogen, carbon dioxide, formates and acetates.
*''[[Biology:Streptococcus bovis|Streptococcus bovis]]'' is an amylolytic, major soluble sugar fermenter, proteolytic, microbe resulting in lactate, acetate and formate.
*''Ruminobacter (Bacteroides) amylophilus''<ref>{{cite journal |doi=10.1016/S0723-2020(86)80078-9 |title=Transfer of Bacteroides amylophilus to a new ''Genus ruminobacter'' gen. nov., nom. Rev. As Ruminobacter amylophilus comb. Nov |journal=Systematic and Applied Microbiology |volume=8 |issue=3 |pages=204–7 |year=1986 |last1=Stackebrandt |first1=Erko |last2=Hippe |first2=Hans }}</ref> amylolytic, [[Chemistry:Propionate|propionate]], proteolytic, organism that forms, [[Chemistry:Formate|formate]]s, acetates and succinates.
*''Prevotella (Bacteroides) ruminocola''<ref>{{cite journal |pmid=7910475 |year=1994 |author1=Avgustin |first1=G |title=Genetic diversity and phylogenetic relationships among strains of Prevotella (Bacteroides) ruminicola from the rumen |journal=International Journal of Systematic Bacteriology |volume=44 |issue=2 |pages=246–55 |last2=Wright |first2=F |last3=Flint |first3=H. J. |doi=10.1099/00207713-44-2-246 |doi-access=free }}</ref> amylolytic, xylanolytic, propionate, proteolytic, microbe that creates, formates, acetates, succinates and propionate.
*''Succinimonas amylolytica'' amylolytic, dextrinolytic, bacteria forming [[Chemistry:Acetate|acetate]]s and succinates.<ref>{{Citation |title=''Bacteroides ruminicola'' N. Sp. and ''Succinimonas amylolytica'' the New Genus and Species: Species of Succinic Acid-Producing Anaerobic Bacteria of the Bovine Rumen | author=M. P. Bryant|display-authors=0| journal=Journal of Bacteriology | year=1958 | volume=76 | issue=1 | pages=15–23 | pmid=13563384| pmc=290147}}</ref>
*''[[Biology:Selenomonas ruminantium|Selenomonas ruminantium]]''<ref>{{cite journal |pmid=16348354 |pmc=185007 |year=1990 |author1=Nisbet |first1=D. J. |title=Effect of Dicarboxylic Acids and Aspergillus oryzae Fermentation Extract on Lactate Uptake by the Ruminal Bacterium Selenomonas ruminantium |journal=Applied and Environmental Microbiology |volume=56 |issue=11 |pages=3515–8 |last2=Martin |first2=S. A. }}</ref> amylolytic, major soluble sugar fermenter, glycerol-utilizing, lactate-utilizing, proteolytic, microbe producing acetates, lactates, hydrogen, carbon dioxide and propionates.
*''Lachnospira multiparus'' propionate, proteolytic, A microbe that results in production of lactate, ethanol, hydrogen, carbon dioxide, formates and acetates.<ref>{{Citation |title=Fermentation of pectin and glucose, and activity of pectin-degrading enzymes in the rumen bacterium Lachnospira multiparus | author=D. Dušková and M. Marounek | journal=Letters in Applied Microbiology | year=2001 | volume=33 | issue=2 | pages=159–163 | doi=10.1046/j.1472-765x.2001.00970.x | doi-access= }}</ref>
*''Succinivibrio dextrinosolvens''<ref>{{cite journal |pmid=8481001 |pmc=202185 |year=1993 |author1=O'Herrin |first1=S. M. |title=Glucose and carbon dioxide metabolism by Succinivibrio dextrinosolvens |journal=Applied and Environmental Microbiology |volume=59 |issue=3 |pages=748–55 |last2=Kenealy |first2=W. R. }}</ref> propionate, dextrinolytic, bacteria forming formates, acetates, lactates and succinates
*''Methanobrevibacter ruminantium'' methanoic, hydrogen utilizing, archaea involved in the creation of methane
*''[[Biology:Methanosarcina barkeri|Methanosarcina barkeri]]'' methanoic, hydrogen utilizing, archaea involved in the creation of methane and carbon dioxide.

==References==
{{Reflist}}

[[Category:Microorganisms]]
[[Category:Digestive system]]
[[Category:Methane]]

{{Sourceattribution|Methanogens in digestive tract of ruminants}}