Methanosaeta thermophila: Difference between revisions

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  their peak performance, the acetate concentration decreases, as well as the ''Methanosaeta''   
  their peak performance, the acetate concentration decreases, as well as the ''Methanosaeta''   
  population.
  population.
<font size=12 color="Purple">●~Pathology~</font>
        ''Methanosaeta thermofiles''are not pathogens and therefore are not disease causing
microbes. To this date, there are no known archaea that are pathogens.

Revision as of 16:19, 5 June 2007

Methanosaeta thermophila


● ~Classification~

            Organism Name:	Methanosaeta thermophila PT
                   Domain:	Archaea
                   Phylum:	Euryarchaeota
                    Class:	Methanomicrobia
                    Order:	Methanosarcinales
                   Family:	Methanosaetaceae
                    Genus: 	Methanosaeta
                   Species:     Methanothrix thermophila
     Genus Species Strain:     Methanosaeta thermophila PT
             Name History:	Synonyms: Methanothrix thermophila PT
                                         Methanothrix thermophila DSM 6194 
                               Equivalent names: Methanosaeta thermophila strain PT
                                                 Methanosaeta thermophila str. PT

●~Description and Significance~


 thermophila are nonmotile, nonsporulating, and thermophilic, which means they thrive at  
 temperatures of 50ºC or higher.
          This microbe was discovered by a molecular technique using fluorogenic PCR (polymerase
 chain reaction, which amplifies DNA) to identify its methanotrophic characteristics and activity
 in marine anoxic microbial communities. This was accomplished by identifying and quantifying the
 mcrA genes. Following amplification, molecular analysis was performed by clone analysis of the 
 16S rRNA and mcrA genes.  The mcrA genes (encoding the methyl coenzyme M reductase, specific to 
 methanogenic archaea), are specific to the various phylogenetic groups of methanotropic Archaea.  
 Methanosaeta thermophila was identified among the microbial communities in deep sediments and 
 “methane seepages of Omine Ridge in the Nankai Trough accretionary prism,” (1).  
           The addition of Methanosaeta to the methanoarchaeal genome sequence compilation offered
 an opportunity to gain significant insight into this intricate microbe and the unique use of 
 comparative genomic approaches allows one to address the nature of these specific microbes and  
 their biological influence and capability. Because these microbes are methanogens, they serve an 
 important role as the producers of natural gas and have potential as creators of biofuels (fuels 
 derived from a biomass).

●~Genome Structure~

           The Methanosaeta thermophila’s genome has been entirely sequenced.  These microbes   
possess circular chromosomes and do not contain plasmids. (The following genome sequence 
information, list, and map of the Methanosaeta thermophila chromosome was taken from eleventh 
source listed under the references section.)
        Genome Sequence: RS: NC_008553     
        Genome Sequence Length: 1879471 
        Statistics: Number of nucleotides: 1879471
                    Number of protein genes: 1696
                    Number of RNA genes: 51
         Genome Statistics                     Number	% of Total
             DNA, total number of bases         total    100.00%		
             DNA G+C number of bases		            0.00% 
             DNA scaffolds	                      0	  100.00%
             Genes total number	              0	  100.00%
             Protein coding genes	              0	    0.00%
             RNA genes	                              0	    0.00%
             rRNA genes	                      0	    0.00%
             5S rRNA	                              0	    0.00%
             16S rRNA	                              0	    0.00%
             18S rRNA	                              0	    0.00%
             23S rRNA	                              0	    0.00%
             28S rRNA	                              0	    0.00%
             tRNA genes                              0	    0.00%
             Other RNA genes	                      0	    0.00%
             Genes with function prediction          0	    0.00%
             Genes without function prediction       0	    0.00%

Genes w/o function with similarity 0 0.00%

             Genes w/o function w/o similarity       0	    0.00%
             Pseudo Genes	                      0	    0.00%
             Genes assigned to enzymes               0	    0.00%
             Genes connected to KEGG pathways	      0	    0.00%
             Genes not connected to KEGG pathway     0	    0.00%
             Genes in ortholog clusters	      0	    0.00%
             Genes in paralog clusters	              0	    0.00%
             Genes in COGs	                      0	    0.00%
             Genes in Pfam	                      0	    0.00%
             Genes in TIGRfam	                      0	    0.00%
             Genes in InterPro	                      0	    0.00%
             Genes with IMG Terms	              0	    0.00%
             Genes in IMG Pathways	              0	    0.00%
             Obsolete Genes	                      0	    0.00%
             Revised Genes	                      0	    0.00%
             Pfam clusters		              0     0.00%
             Paralogous groups		              0   100.00%
             Orthologous groups		      0     0.00%

●~Cell Structure and Metabolism~

      Methanosaeta thermophila is circular (coccus), with one inner membrane and one cell wall.   
This microbe does not interact with other organisms, grows extremely slow, does not contain  
plasmids, does not possess flagella, but they do however produce gas vacuoles to help them move in  
aquatic environments. Gas vacuoles are cavities within the cytoplasm, which contain a gas similar     
to that of their surrounding atmosphere. These vacuoles serve as floatation devices because they  
decrease in size when subjected to increased hydrostatic pressure. So although they are nonmotile, 
their gas vacuoles allow some degree of flexibility in regards to how much movement they have in 
aquatic environments.    
      Methanosaeta thermophila obtain their energy as a “thermophilic obligately-aceticlastic 
methane-producing archaeon,” which means that they produce methane from acetate, (4).  Although 
approximately two-thirds of all methane is derived from the methyl group of acetate,  
Methanosaeta are able to utilize acetate as a substrate for methanogenesis.    
Methanosarcina is the only other genus of methanoarchaea that are capable of utilizing acetate 
as a substrate, as well as using H2/CO2, dimethylsulfide, and and methanethiol compounds as 
substrates.  Unlike the faster-growing Methanosarcina, which prefers methylated compounds to 
acetate, Methanosaeta is a slow-growing specialist that utilizes acetate only.


●~Ecology~

       The environment at which Methanosaeta thermophiles are found is aquatic (living and 
growing in water) and they exhibit optimal growth between 55-60°C. Although they are present in 
many environments, such as anaerobic digesters, anaerobic biofilms, sediments, and anaerobic 
sludges, they are predominantly found in rice paddies, which allow a continuous stream of water to 
flow through them. Acetate is the most important substrate for methanogenesis in rice paddies and 
studies have shown that the concentration of acetate in flooded rice paddies is in the 5-100 mM 
range, and Methanosaeta thermophiles are the predominant acetate-utilizing methanoarchaea in 
these aquatic rice paddies.   
      Methanosaeta species are the most prevalent methanogenic archaea of the microbial 
population in numerous environments, including rough sludge digesters, solid wastes, sewage slush, 
and anaerobic reactors.  During activation of anaerobic bioreactors, Methanosaeta species are  
widespread due to the high acetate concentration. However, as bioreactors become stable and attain 
their peak performance, the acetate concentration decreases, as well as the Methanosaeta   
population.


●~Pathology~

       Methanosaeta thermofilesare not pathogens and therefore are not disease causing 
microbes. To this date, there are no known archaea that are pathogens.