Mycoplana

Mycoplana
Systematics
Domain :	Bacteria (bacteria)
Department :	Proteobacteria
Class :	Alphaproteobacteria
Order :	Rhizobiales
Family :	Brucellaceae
Genre :	Mycoplana
Scientific name
	Mycoplana
	Gray and Thornton 1928 emend. Urakami et al. 1990
species
	Mycoplana dimorpha Gray & Thornton 1928 ; Mycoplana ramosa Urakami et al. 1990 ;

Mycoplana is a genus of bacteria . It is one of the gram-negative bacteria. Mycoplana occurs in the soil.

features

Appearance

The cells are slightly curved or irregularly shaped rods . Initially, the cells can form filaments, which can also be branched. After a while, the filaments break up into irregular rods. The diameter of the individual, rod-shaped cells of the Mycoplana ramosa species is in the range of 0.5–0.8 µm with a length of 2.0–3.0 µm. Mycoplana is mobile ( motile ) due to a perithric flagella . Spores are not formed. The Gram stain is negative.

The cells grow into colonies on solid nutrient media , which are white to light yellow in color.

Growth and metabolism

The metabolism of Mycoplana is aerobic , i. H. the representatives of the genus can only multiply if oxygen is present. There is no fermentation . A photosynthesis does not take place, the species is heterotrophic . The catalase and oxidase tests are positive. The pH value for best growth is 6.0–8.0, the optimal temperature for incubation is 30 ° C. Mycoplana does not tolerate large amounts of sodium chloride (NaCl) in the nutrient medium; growth no longer occurs at a content of 3% NaCl.

The representatives of the genus have the enzyme urease and can therefore break down urea . You can use various amino acids and peptone as a source of nitrogen. They are unable to break down gelatin or starch through hydrolysis . Nitrate is not reduced to nitrite . Hydrogen sulfide (H ₂ S) is not formed, nor is indole formed (negative indole test ). The methyl red sample is also negative. In contrast, the Voges-Proskauer test for the detection of acetoin formation is positive. Mycoplana produces granules of poly-β-hydroxybutyrate , these granules in the cytoplasm serve as storage material .

As part of the chemoorgano-heterotrophic metabolism, Mycoplana species can oxidatively use various carbohydrates as carbon and energy sources, including: a. the monosaccharides L - arabinose , D - fructose , D - galactose , D - glucose , D - mannose and D - xylose . The sugar alcohols glycerin (glycerol), D - mannitol and D - sorbitol are also used with acid formation. Carbohydrates that are not broken down with acid formation are, for example, the disaccharides lactose , maltose , sucrose and trehalose . With the sugar alcohols tested, there is no acid formation with myo - inositol .

Chemotaxonomic Features

Mycoplana contains ubiquinone-10 (Q-10) as the main ubiquinone . The GC content (the proportion of the nucleobases guanine and cytosine ) in the bacterial DNA is between 63 and 68 mol percent.

The fatty acids found in the membrane lipids are molecules with an even number of carbon atoms and no branching in the carbon chain . Mainly an unsaturated octadecenoic acid (a fatty acid with a double bond , briefly described as C18: 1) occurs, but the description of the species does not specify which fatty acid is involved, since the position of the double bond is not specified (see list of fatty acids and shorter monocarboxylic acids ). The proportion of fatty acids C18: 1 is between 67.9 and 76.5%. Furthermore, an unsaturated hexadecenoic acid (described as C16: 1) and the saturated fatty acid hexadecanoic acid ( palmitic acid , contains no double bond, abbreviation C16: 0) occur in larger quantities. Also noteworthy is the occurrence of a fatty acid with a hydroxyl group , it is 3-hydroxytetradecanoic acid (abbreviation 3-OH-C14: 0), its proportion is 1.1–2.5%.

Pathogenicity

The species M. dimorpha and M. ramosa are non- pathogenic (“pathogenic”), they are assigned to risk group 1 by the Biological Agents Ordinance in conjunction with the TRBA ( Technical Rules for Biological Agents) 466 .

Systematics

Mycoplana one of the family of Brucellaceae which to the class of Alphaproteobacteria is provided. Originally, Mycoplana - despite the negative Gram staining - was counted among the Actinobacteria and initially assigned to the Mycobacteriaceae family . In 1957 it was assigned to the Pseudomonadaceae family . It was not until phylogenetic studies from 2001 that the genus was related to the group of bacteria known at the time as "Rhizobia", to which the genera Rhizobium and Agrobacterium were counted. As a result, they are put together in the order of the Rhizobiales , but in different families.

The two species, originally assigned to the genus, Mycoplana bullata , first described by Gray and Thornton in 1928 , and Mycoplana segnis , by Urakami et al. described in 1990, have been changed within the system . M. bullata is now assigned to the genus Brevundimonas , M. segnis to Caulobacter . There are currently (December 2015) two species of the genus Mycoplana :

Mycoplana dimorpha Gray & Thornton 1928 (the type species )
Mycoplana ramosa Urakami et al. 1990

etymology

The generic name Mycoplana is made up of the two words mykos ("mushroom") and planos (Greek for "wandering"). It refers to the mobility and resemblance to mushrooms (the genus creates filaments, which mushrooms do too).

Occurrence and meaning

In Mycoplana is bacteria in the soil occur. With their branched filaments they resemble the representatives of the genera Streptomyces or Rhodococcus . These are also soil bacteria, but belong to the order of Actinomycetales , which are gram-positive bacteria. In the first description by Gray and Thornton, reference is made to the ability of bacteria to break down residues of aromatic compounds in the soil .

swell

literature

George M. Garrity: Bergey's Manual of Systematic Bacteriology: Volume 2: The Proteobacteria Part C: The Alpha-, Beta-, Delta-, and Epsilonproteabacteria . 2nd edition, Springer, New York 2005, ISBN 0-387-24145-0

Individual evidence

↑ ^a ^b ^c George M. Garrity: Bergey's Manual of Systematic Bacteriology: Volume 2: The Proteobacteria Part C: The Alpha-, Beta-, Delta-, and Epsilonproteabacteria . 2nd edition, Springer, New York 2005, ISBN 0-387-24145-0
↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j T. Urakami, H. Oyanagi u. a .: Recharacterization and Emended Description of the Genus Mycoplana and Description of Two New Species, Mycoplana ramosa and Mycoplana segnis. In: International Journal of Systematic Bacteriology. Volume 40, No. 4, October 1990, pp. 434-442, ISSN 0020-7713 . doi : 10.1099 / 00207713-40-4-434 .
↑ TRBA (Technical Rules for Biological Agents) 466: Classification of prokaryotes (Bacteria and Archaea) into risk groups. In: Website of the Federal Institute for Occupational Safety and Health (BAuA). April 25, 2012, p. 144 , accessed April 1, 2014 .
↑ ^a ^b ^c ^d ^e Jean Euzéby, Aidan C. Parte: Genus Mycoplana. In: List of Prokaryotic names with Standing in Nomenclature ( LPSN ). Retrieved December 3, 2015 .
↑ ^a ^b P. HH Gray, HG Thornton: Soil bacteria decompose certain aromatic compounds. In: Zentralblatt für Bakteriologie, Parasitenkunde, Infectious Diseases and Hygiene. Second natural science department. Volume 73, 1928, pp. 74-96.
^ MW Gaunt, SL Turner et al. a .: Phylogenies of atpD and recA support the small subunit rRNA-based classification of rhizobia. In: International journal of systematic and evolutionary microbiology. Volume 51, No. 6, November 2001, pp. 2037-2048, ISSN 1466-5026 . doi : 10.1099 / 00207713-51-6-2037 . PMID 11760945 .

[Bergey-1] George M. Garrity: Bergey's Manual of Systematic Bacteriology: Volume 2: The Proteobacteria Part C: The Alpha-, Beta-, Delta-, and Epsilonproteabacteria . 2nd edition, Springer, New York 2005, ISBN 0-387-24145-0

[Urakami-2] ↑ ^a ^b ^c ^d ^e ^f ^g ^h ⁱ ^j T. Urakami, H. Oyanagi u. a .: Recharacterization and Emended Description of the Genus Mycoplana and Description of Two New Species, Mycoplana ramosa and Mycoplana segnis. In: International Journal of Systematic Bacteriology. Volume 40, No. 4, October 1990, pp. 434-442, ISSN 0020-7713 . doi : 10.1099 / 00207713-40-4-434 .

[trba-3] TRBA (Technical Rules for Biological Agents) 466: Classification of prokaryotes (Bacteria and Archaea) into risk groups. In: Website of the Federal Institute for Occupational Safety and Health (BAuA). April 25, 2012, p. 144 , accessed April 1, 2014 .

[lpsn-4] Jean Euzéby, Aidan C. Parte: Genus Mycoplana. In: List of Prokaryotic names with Standing in Nomenclature ( LPSN ). Retrieved December 3, 2015 .

[Gray-5] P. HH Gray, HG Thornton: Soil bacteria decompose certain aromatic compounds. In: Zentralblatt für Bakteriologie, Parasitenkunde, Infectious Diseases and Hygiene. Second natural science department. Volume 73, 1928, pp. 74-96.

[PMID11760945-6] MW Gaunt, SL Turner et al. a .: Phylogenies of atpD and recA support the small subunit rRNA-based classification of rhizobia. In: International journal of systematic and evolutionary microbiology. Volume 51, No. 6, November 2001, pp. 2037-2048, ISSN 1466-5026 . doi : 10.1099 / 00207713-51-6-2037 . PMID 11760945 .