Methanobrevibacter Smithii: Difference between revisions
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==Ecology (including pathogenesis)== | ==Ecology (including pathogenesis)== | ||
Methanobrevibacter smithii is found in the human colon, which is the last part of the digestive system in most vertebrates. The pH of the colon varies between 5.5 and 7, from slightly acid to neutral (1). | |||
==Interesting feature== | ==Interesting feature== | ||
Revision as of 16:48, 24 October 2011
A Microbial Biorealm page on the genus Methanobrevibacter Smithii
Classification
Archaea; Euryarchaeota; Methanobacteria; Methanobacteriales; Methanobacteriaceae; Methanobrevibacter
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NCBI: Taxonomy |
Description and significance
Methanobrevibacter smithii is a methanogenic Euryarchaeote. It makes up 10% of all anaerobes in the colons of healthy adults, making it the dominant archaeon in the human gut ecosystem. Metagenomic studies compared gut microbial communities of genetically obese mice with lean mice and found that obese mice contain a higher representation of genes involved in polysaccharide degradation and have more archaea. Methanobrevibacter smithii affects specificity and efficiency of bacterial digestion of dietary polysaccharides, influencing the person’s calorie harvest and body fat. This suggests that Methanobrevibacter smithii may be a therapeutic target for reducing energy harvest in obese humans (3).
Genome structure
The sequence was released Jun 6 2007 by Washington University. The Methanobrevibacter smithii ATCC 35061 genome is 1.85 Million bp long and composed of approximately 1837 predicted genes. The chromosomes are circular (3).
Cell structure, metabolism & life cycle
The Methanobrevibacter smithii cell is identified as coccobacillus. Optimum temperature and pH for growth is 38°C and 6.9-7.4, respectively (4). Microbes in our colons encode enzymes that help digest complex dietary polysachharides and proteins. Bacterial fermentation of polysaccharides produces short chain fatty acids, other organic acids, alchohols, and gases (CO2 and H2). Methanobrevibacter smithii is a methanogen that reduces CO2 with H2 to methane. The process of methonogenesis prevents accumulation of H2 in the human gut and improves the efficiency of microbial fermentation (3).
Ecology (including pathogenesis)
Methanobrevibacter smithii is found in the human colon, which is the last part of the digestive system in most vertebrates. The pH of the colon varies between 5.5 and 7, from slightly acid to neutral (1).
Interesting feature
Describe in detail one particularly interesting aspect of your organism or it's affect on humans or the environment.
