Flexithrix dorotheae
| Flexithrix dorotheae | ||||||||||||
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| Systematics | ||||||||||||
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| Scientific name of the genus | ||||||||||||
| Flexithrix | ||||||||||||
| Lewin 1970 | ||||||||||||
| Scientific name of the species | ||||||||||||
| Flexithrix dorotheae | ||||||||||||
| Lewin 1970 |
Flexithrix dorotheae is a species of bacteria and belongs to the Flammeovirgaceae family . It is the only species in the genus Flexithrix .
Appearance
The cells of Flexithrix dorotheae are rod-shaped. The size is 0.4–0.9 µm in width and 1.5–70 µm or more in length. They can form longer cell threads ( filaments ) from several cells. These filaments can break down into individual cells, and the cells can then form new filaments again. They are not flagellated , but there is a sliding movement of individual cells, one speaks of gliding motility . The color of the colonies is golden yellow to yellow. Dyes are carotenoids , especially zeaxanthin . Flexirubin pigments are not present. Growth takes place at an NaCl content of 1–5%, the optimum is 3%. Spores are not formed.
Growth and metabolism
Flexithrix dorotheae is chemo-organotrophic . The metabolism is the breathing , the species are strictly aerobic . Growth takes place at pH values of 6 to 11, the pH value for the best growth is 7. Tolerated temperatures at which growth takes place are in the range from 10 to 40 ° C, optimal growth takes place at 25–30 ° C.
The oxidase test and the catalase test are positive. The activity of urease is either weak or absent. The bacterium does not reduce nitrate . Hydrogen sulfide (H 2 S) is not formed. Esculin , gelatine , starch and Tween 80 are broken down. Indole is not formed.
Chemotaxonomy
Flexithrix dorotheae is gram negative . The respiratory quinone is menaquinone -7 (MK-7). Dominant fatty acids are iso C 15: 0 and C 16: 1 ω5c. The proportion of the bases guanine and cytosine within the DNA , usually referred to as the GC content , is between 35.9 and 36.1%.
The presence of iso C 15: 0 and C 16: 1 ω5c as the main fatty acids and zeaxanthin as the main carotenoid are useful features for distinguishing Flexithrix dorotheae from the closely related genera Flammeovirga and Persicobacter .
Occurrence
The bacterium Flexithrix dorotheae is a marine organism. a. in the sea mud.
Systematics
The species was first described by Ralph A. Lewin in 1970. It belongs to the Flammeovirgaceae family, which is part of the Bacteroidetes division .
Individual evidence
- ↑ Systematics according to JP Euzéby: List of Prokaryotic names with Standing in Nomenclature (LPSN) (as of June 15, 2020)
literature
- War, NR; Ludwig, W .; Whitman, WB; Hedlund, BP; Paster, BJ; Staley, JT; Ward, N .; Brown, D .; Parte, A .: Bergey's Manual of Systematic Bacteriology. Volume 4: The Bacteroidetes, Spirochaetes, Tenericutes (Mollicutes), Acidobacteria, Fibrobacteres, Fusobacteria, Dictyoglomi, Gemmatimonadetes, Lentisphaerae, Verrucomicrobia, Chlamydiae, and Planctomycetes . Springer, 2010, ISBN 978-0-387-68572-4 , pp. 448-450 .
- Jiri Hausler: Freshwater Flora of Central Europe, Vol. 20: Schizomycetes . Springer, 1982, ISBN 978-3-8274-2141-8 , pp. 156 .