Deltaproteobacteria
| Deltaproteobacteria | ||||||||
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Desulfovibrio vulgaris |
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| Systematics | ||||||||
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| Scientific name | ||||||||
| Deltaproteobacteria | ||||||||
| Kuever et al. 2006 |
The Deltaproteobacteria (also δ-Proteobacteria) form a class of the phylum (strain) of the Proteobacteria in the phylogenetic system of the bacteria , which was established on the basis of the base sequence of the ribosomal 16S ribonucleic acid . All representatives of this tribe are gram-negative .
Physiology and ecology
Compared to other classes of Proteobacteria, δ-Proteobacteria are physiologically rather homogeneous: almost all sulfate-reducing bacteria belong to this group. Many representatives are therefore viable even without oxygen and are particularly widespread in the sediment of lakes, in the sea floor or in swamps and moors. The classic putrid smell is caused by hydrogen sulphide (H 2 S), which sulphate-reducing bacteria produce during the chemical reduction of oxidized sulfur compounds. While aerobic organisms such as plants, animals and most fungi reduce oxygen to water (O 2 + 4 {H} → 2 H 2 O), sulfate reducers can use sulfur compounds, especially sulfate, as electron acceptors: SO 4 2− + 8 {H } + H + → HS - + 4 H 2 O. The deltaproteobacteria thus perform central functions in the natural sulfur cycle . With their metabolism, they reduce the sulfate formed by geochemical processes or bacterial sulfide and sulfur oxidation back to H 2 S.
Important genera
In addition to the sulphate reducers, the Deltaproteobacteria also include some of the most unusual bacteria: Bdellovibrio, for example, is a single bacterium that hunts other bacteria. Myxobacteria , on the other hand, are able to cooperatively overwhelm other bacteria like a wolf pack and to feed on them. If the food base is exhausted, myxobacteria develop multicellular, complex fruiting bodies and resistant spores. They are the most complex of all bacteria known to date and are on the threshold of multicellularity. Other important genera of Deltaproteobacteria are Desulfovibrio and Geobacter .
Systematics
The Deltaproteobacteria include the following orders:
- Bdellovibrionales Garrity et al. 2006
- Desulfarculales corrig. Kuever et al. 2006
- Desulfobacterales Kuever et al. 2006
- Desulfovibrionales Kuever et al. 2006
- Desulfurellales Kuever et al. 2006
- Desulfuromonadales corrig. Kuever et al. 2006
- Myxococcales Tchan et al. 1948
- Syntrophobacterales Kuever et al. 2006
and numerous isolates that have not yet been classified with certainty.
swell
- ↑ JP Euzéby: List of Prokaryotic names with Standing in Nomenclature - Deltaproteobacteria ( Memento of the original from January 27, 2013 in the Internet Archive ) Info: The archive link was inserted automatically and has not yet been checked. Please check the original and archive link according to the instructions and then remove this notice. Status: January 24, 2013
literature
- Martin Dworkin, Stanley Falkow, Eugene Rosenberg, Karl-Heinz Schleifer, Erko Stackebrandt (Eds.) The Prokaryotes, A Handbook of the Biology of Bacteria . 7 volumes, 3rd edition, Springer-Verlag, New York et al. O., 2006, ISBN 0-387-30740-0 . Vol. 7: Proteobacteria: Delta and Epsilon Subclass ISBN 0-387-30747-8