''Meiothermus'' is a genus of ''
Deinococcota
''Deinococcota'' (synonym, ''Deinococcus-Thermus'') is a phylum of bacteria with a single class, ''Deinococci'', that are highly resistant to environmental hazards, also known as extremophiles.
These bacteria have thick cell walls that give them ...
''
bacteria
Bacteria (; singular: bacterium) are ubiquitous, mostly free-living organisms often consisting of one Cell (biology), biological cell. They constitute a large domain (biology), domain of prokaryotic microorganisms. Typically a few micrometr ...
.
Members of ''Meiothermus'' can be reliably distinguished from other genera in the family ''
Thermaceae
''Thermales'' is an order of bacteria belonging to the ''Deinococcota'' phylum. They are particularly resistant to heat, and live in the benthic zone of the Gulf of Mexico.
Members of the order ''Thermales'' can be distinguished from all other ...
'' as well as all other bacteria by the presence of three
conserved signature indels Conserved signature inserts and deletions (CSIs) in protein sequences provide an important category of molecular markers for understanding phylogenetic relationships. CSIs, brought about by rare genetic changes, provide useful phylogenetic markers ...
(CSIs) found in the proteins: 5-methyltetrahydrofolate–homocysteine methyltransferase, cadmium transporter and
polynucleotide phosphorylase
Polynucleotide Phosphorylase (PNPase) is a bifunctional enzyme with a phosphorolytic 3' to 5' exoribonuclease activity and a 3'-terminal oligonucleotide polymerase activity. That is, it dismantles the RNA chain starting at the 3' end and working ...
and are exclusively shared by species of this genus. ''Meiothermus'' is also different than the ''
Thermus
''Thermus'' is a genus of thermophilic bacteria. It is one of several bacteria belonging to the ''Deinococcota'' phylum. ''Thermus'' species can be distinguished from other genera in the family ''Thermaceae'' as well as all other bacteria by th ...
'' genus, which it was originally a member of, in their optimum growth temperatures, with ''Meiothermus'' being able to grow in colder environments. ''Meiothermus'' was first isolated with ''Thermus'' in alkaline and neutral hot springs in
Kamchatka
The Kamchatka Peninsula (russian: полуостров Камчатка, Poluostrov Kamchatka, ) is a peninsula in the Russian Far East, with an area of about . The Pacific Ocean and the Sea of Okhotsk make up the peninsula's eastern and west ...
, Russia and
Yellowstone National Park
Yellowstone National Park is an American national park located in the western United States, largely in the northwest corner of Wyoming and extending into Montana and Idaho. It was established by the 42nd U.S. Congress with the Yellowst ...
, USA.
Characteristics
''Meiothermus'' species of bacteria are
gram-negative
Gram-negative bacteria are bacteria that do not retain the crystal violet stain used in the Gram staining method of bacterial differentiation. They are characterized by their cell envelopes, which are composed of a thin peptidoglycan cell wa ...
and are primarily chemoorganoheterotrophs, but some species can use
nitrate as an electron acceptor.
The ''Meiothermus'' genus was originally proposed to group together several moderately
thermophilic
A thermophile is an organism—a type of extremophile—that thrives at relatively high temperatures, between . Many thermophiles are archaea, though they can be bacteria or fungi. Thermophilic eubacteria are suggested to have been among the earl ...
organisms that were in the ''Thermus'' genus. It was later differentiated and made its own genus. ''Meiothermus'' are mostly distinguishable from ''Thermus'' by the lower bound of their optimum growth temperatures, 50-60°C for ''Meiothermus'' and 70°C for ''Thermus.'' Also, in ''Meiothermus,'' the presence of two glycolipid bands is seen whereas ''Thermus'' species only contain one.
''Thermus'' also contains eight
conserved signature indels Conserved signature inserts and deletions (CSIs) in protein sequences provide an important category of molecular markers for understanding phylogenetic relationships. CSIs, brought about by rare genetic changes, provide useful phylogenetic markers ...
(CSIs) compared to the three that ''Meiothermus'' has. The optimal
pH range for ''Meiothermus'' growth is in the range of 7.5-9.5.
''Meiothermus'' is a genus of bacteria that can only exist in aerobic environments. Most ''Meiothermus'' species have a red pigmentation with the exception of ''M. chilarophilus'' which has a yellow color.
Some ''Meiothermus'' species can also form biofilms and stick to surfaces using specific adhesion organelles.
Habitats
''Meiothermus'' is a thermophilic genus of bacteria.
Thermophiles
A thermophile is an organism—a type of extremophile—that thrives at relatively high temperatures, between . Many thermophiles are archaea, though they can be bacteria or fungi. Thermophilic eubacteria are suggested to have been among the earl ...
are strains of bacteria that exist in environments that range from 45°C to around 80°C.
''Meiothermus'' in particular is best suited to ranges of 50-60°C.
''Meiothermus'' is a strictly aerobic bacteria, needing oxygen for many of its processes.
[Mark D. Spanevello, Bharat K.C. Patel, The phylogenetic diversity of ''Thermus'' and ''Meiothermus'' from microbial mats of an Australian subsurface aquifer runoff channel, ''FEMS Microbiology Ecology'', Volume 50, Issue 1, October 2004, Pages 63–73, https://doi.org/10.1016/j.femsec.2004.05.008]
Metabolism
Some species of ''Meiothermus'' have the ability to break down
keratin
Keratin () is one of a family of structural fibrous proteins also known as ''scleroproteins''. Alpha-keratin (α-keratin) is a type of keratin found in vertebrates. It is the key structural material making up scales, hair, nails, feathers, ho ...
at much a rate much higher than natural rates. These keratinolytic processes performed by ''Meiothermus'' species like the common ''M. ruber'' lead to production of amino acids that can be used by the environment.
''Meiothermus'' can use other organic substrates like starch, disaccharides, amino acids and others as a carbon and energy source.
Phylogeny
The currently accepted taxonomy is based on the
''List of Pro''karyotic names with Standing in Nomenclature (LSPN)
and the
National Center for Biotechnology Information
The National Center for Biotechnology Information (NCBI) is part of the United States National Library of Medicine (NLM), a branch of the National Institutes of Health (NIH). It is approved and funded by the government of the United States. The ...
.
Unassigned species:
* ''
Meiothermus rosaceus
''Meiothermus'' is a genus of ''Deinococcota'' bacteria.
Members of ''Meiothermus'' can be reliably distinguished from other genera in the family ''Thermaceae'' as well as all other bacteria by the presence of three conserved signature indels ...
''
Chen et al. 2002
See also
*
List of bacteria genera This article lists the genera of the bacteria. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI). However many taxonomic names are ...
*
List of bacterial orders
This article lists the orders of the Bacteria. The currently accepted taxonomy is based on the List of Prokaryotic names with Standing in Nomenclature (LPSN) and National Center for Biotechnology Information (NCBI)
and the phylogeny is based on 16S ...
References
Deinococcota
Gram-negative bacteria
Bacteria genera
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