Amycolatopsis

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Amycolatopsis
Systematics
Domain : Bacteria (bacteria)
Department : Actinobacteria
Order : Pseudonocardiales
Subordination : Pseudonocardineae
Family : Pseudonocardiaceae
Genre : Amycolatopsis
Scientific name
Amycolatopsis
Lechevalier et al. 1986 emend. Tang et al. 2010

Amycolatopsis is a genus of bacteria in the family of Pseudonocardiaceae in the order of Actinomycetales . All species of the genus are gram-positive with a high GC content in the bacterial DNA . Like other representatives of the Actinomycetales, they form filamentous cell structures thatresemblethe hyphae of fungi . As a result, some species were previously assigned to other genera, such as Streptomyces or Nocardia , which are also counted among the Actinomycetales. Like Streptomyces , many species of Amycolatopsis produce antibiotics and can be found in the soil.

features

Appearance

The cells of the species of Amycolatopsis are gram positive . The cells are in the form of filaments, which is typical for many representatives of the Actinomycetales . These structures, which resemble the hyphae of fungi, have a diameter of 0.5–2.0 µm and are branched. The hyphae often disintegrate into individual cube-shaped cells. As with mushrooms, a distinction can be made between air and substrate mycelium . The substrate mycelium develops in the nutrient medium , while the aerial mycelium is formed from cells that grow in the gas space above the nutrient medium. Both the substrate mycelium and the aerial mycelium can be colored, and pigments are also released into the nutrient medium. However, not all species develop aerial mycelium. If present, these hyphae can also be observed to fragment at the upper end. Chains of spore-like , cube-shaped to ovoid cells are formed. The endospores typical for other types of bacteria (e.g. Bacillus or Sporosarcina ) are not formed. Amycolatopsis cells are incapable of active movement . In contrast to the genera Nocardia and Mycobacterium , the bacterial cell wall is not acid-resistant .

Growth and metabolism

All species of Amycolatopsis are heterotrophic , they do not photosynthesize . Some species are strictly aerobic ; H. dependent on oxygen. Others are facultatively aerobic, they can also live in the absence of oxygen. The catalase test is positive. Amycolatopsis species can use numerous organic compounds for their metabolism and break them down, various carbohydrates and sugar alcohols are used with acid formation. The temperatures for optimal growth are between 20 and 30 ° C for most species, they are mesophilic . The optimal pH of the nutrient medium for most species is between 6.0 and 9.0.

Investigations by Shu-Kun Tang et al. a. 2010 led to an expanded description of the genus. The researchers found that alkaliphilic species (bacteria that prefer higher pH levels for growth) and halophilic species (these require higher concentrations of sodium chloride for growth) also belong to the genus. In addition to the mesophilic species, the genus also includes thermophilic species, i.e. bacteria that prefer higher temperatures for growth. So z. B. Amycolatopsis halophila optimal when the nutrient medium contains 5% NaCl and tolerates a salt content of up to 15%. It grows optimally at 37 ° C and can tolerate temperatures of up to 45 ° C. The thermophilia is even more pronounced in A. eurytherma , A. methanolica and A. thermoflava , which can still grow well at 50 ° C.

For the cultivation of Amycolatopsis types available, standard culture media can be used, on the basis of peptone (such as trypticase soy agar ) and yeast extract . Certain additives are often used. Mannitol or glycerin (glycerol) are suitable additives , soybean flour , starch and oat flour are also used. Other supplines (substances that promote growth) are asparagine and tyrosine . The culture media must be incubated for a longer period of time until colonies are visible, 14 days is usual.

Chemotaxonomic Features

The murein layer in the cell wall contains the amino acid meso - diaminopimelic acid as a diagnostically important amino acid in the peptide bridge, as well as glutamic acid and alanine . The peptidoglycan type is A1γ. Diagnostically important sugars are galactose and arabinose . The extended description of the genus by Shu-Kun Tang et al. a. However, 2010 showed that arabinose is not always present or can only occur in traces. Mycolic acids are not formed. The main menaquinone is MK-9 (H 2 ) or MK-9 (H 4 ). According to Tang, there are mainly MK-9 (H 4 ) or MK-8 (H 4 ). The phospholipids in the cell membrane correspond to the type II phospholipid pattern, either phosphatidylethanolamine or phosphatidylmethylethanolamine is present or both compounds are present. There are also other phosphoglycerides . A few typical fatty acids in the cell membrane cannot be determined. The fatty acid pattern includes saturated fatty acids , such as C 16: 0 (hexadecanoic acid or palmitic acid ) and C 17: 0 (heptadecanoic acid or margaric acid ), as well as branched-chain fatty acids , such as iso -C 15: 0 (iso- pentadecanoic acid ) and iso -C 16 : 0 (iso-hexadecanoic acid) occur. 2-Hydroxy fatty acids (compare α- hydroxycarboxylic acids ) such as iso -C 15: 0  2-OH can also be found.

The GC content in the bacterial DNA is 66 to 75 mol percent, which corresponds to the classification in the Actinobacteria division . The genome of several species has already been completely sequenced . Similar to Streptomyces species, which also have a pronounced secondary metabolism , the size of the genome also attracts attention. In A. orientalis , the genome size of the bacterial chromosome is 8949 kilobase pairs (kb), which is almost twice the genome size of Escherichia coli (4600 kb). In contrast to Streptomyces species (which have a linear chromosome), the bacterial chromosome of the Amycolatopsis species investigated to date is a circular molecule. Even plasmids were found for. B. in A. orientalis and A. benzoatilytica .

Systematics

External system

The genus Amycolatopsis in the family of the Pseudonocardiaceae is placed under the subordination of the Pseudonocardineae in the order of the Actinomycetales. Since 2011, the Pseudonocardiaceae family (see note 1 ) contains, in addition to Amycolatopsis and Prauserella , other genera that were previously included in the Actinosynnemataceae family, such as the Saccharothrix genus .

Internal system

Amycolatopsis orientalis is the type species of the genus. More than 60 species ofthe genus Amycolatopsis are known (as of 2014):

Remarks

  1. In 2011, it was proposed to combine the Actinosynnemataceae and Pseudonocardiaceae families into the extended family Pseudonocardiaceae.
  2. In 1986 Amycolatopsis orientalis subsp. lurida was introduced as a subspecies of Amycolatopsis orientalis , as there were only very few differences in the traits examined at the time. Thus, according to the rules of the bacterial system, the subspecies Amycolatopsis orientalis subsp. orientalis set. Further investigations from 2004 showed, however, that Amycolatopsis lurida is a separate species, so the remaining subspecies can again be referred to as Amycolatopsis orientalis .

In the genus there are currently (as of 2014) 61 described species . Although Amycolatopsis is widespread in nature, only some of the species have been described so far. The genus is the subject of intense research. Between 2004 and 2006 alone, 11 new species of the genus were described, in the period from 2007 to February 2014 there were 29 new species. There are synonyms for numerous species because they were previously assigned to other genera, in particular the genera Nocardia and Streptomyces . These genera also belong to the order of Actinomycetales and before the establishment of the genus Amycolatopsis in 1986, species were assigned to the genera known at the time. The type species Amycolatopsis orientalis was first described in 1956 as Streptomyces orientalis , classified as Nocardia orientalis in 1970 and again assigned to another genus in 1981 as Actinomyces orientalis . Also Amycolatopsis lurida is under the synonym Nocardia lurida out.

etymology

The genus Amycolatopsis was first described in 1986 by Mary P. Lechevalier , simultaneously with the genus Amycolata . However, this genus was dissolved in 1994 and the representatives of the genus Pseudonocardia were assigned . The generic name Amycolata is made up of the Greek prefix a (negation, “not”), the Greek word myces (“mushroom”) and the Latin suffix ata ( denoting a relationship of origin). This emphasizes the distinction between the newly discovered genus and the genera Mycobacterium , Nocardia , Rhodococcus and Corynebacterium (in the order Actinomycetales) known at that time, since Amycolata does not have mycolic acids (certain fatty acids). The generic name Amycolatopsis in turn refers to Amycolata , with the addition of the Greek word opsis ("appearance") it is shown that Amycolatopsis has a similar appearance to Amycolata .

Occurrence and meaning

The habitat of Amycolatopsis species is typically the soil , similar to the representatives of the genera Nocardia , Streptomyces or Rhodococcus . For example, A. orientalis , A. lurida and A. mediterranei were isolated from the soil. Also A. keratiniphila comes from the ground and was in Kuwait found during the search in India to the discovery of A. balhimycina , A. tolypomycina and A. vancoresmycina led. A. ultiminotia was discovered in the rhizosphere . Also arid soils are the habitat of many species, such as in the Atacama . Also from vegetable waste, plant material, clinical samples, the wall of a hypo-related cavity , ocean sediment and the sediment of a salt lake were Amycolatopsis TYPES isolated. A veterinary medi hiss importance some species (eg. B. A. kentuckyensis ) to, as they have a placentitis can cause (infection of the uterus) in horses.

Many species of the genus play an important ecological role in the breakdown of substances, since they can only break down organic compounds such as methanol ( A. methanolica ) and keratin ( A. keratiniphila ) that are difficult to decompose . Also aromatic hydrocarbons can be degraded such. B. meta - hydroxybenzoic acid by A. benzoatilytica . Some species are extremely heavy metal tolerant and can endure high concentrations of nickel or copper . A. tucumanensis is even able to absorb copper from contaminated soil and can therefore be considered for microbiological remediation. Some strains can make vanillin from ferulic acid.

Antibiotics are produced by numerous species of the genus , e.g. B. ristocetin by A. lurida . The investigation of soil samples in India with the aim of finding bacterial strains that produce antibiotics that act against MRSA (methicillin-resistant Staphylococcus aureus ) was successful in 2003: The glycopeptide antibiotic vancomycin is synthesized by A. vancoresmycina . Further antibiotics effective against MRSA are tolypomycin and nogabecin , which are caused by A. tolypomycina and A. keratiniphila subsp. nogabecina are produced. The rifamycins , a separate group of antibiotics, are also synthesized by Amycolatopsis species. This was initially observed in a bacterial strain of A. mediterranei , which was established in 2004 as a separate species A. rifamycinica .

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literature

  • Michael Goodfellow, Peter Kämper, Hans-Jürgen Busse, Martha E. Trujillo, Ken-ichiro Suzuki, Wolfgang Ludwig, William B. Whitman (Eds.): Bergey's Manual of Systematic Bacteriology: Volume 5: The Actinobacteria . 2nd Edition. Springer-Verlag, New York 2012, ISBN 978-0-387-95043-3 , pp. 1334-1358 , doi : 10.1007 / 978-0-387-68233-4 .

Individual evidence

  1. ↑ a b c d e f g h i j M. P. Lechevalier, H. Prauser, DP Labeda, J.-S. Ruan: Two New Genera of Nocardioform Actinomycetes: Amycolata gen. Nov. and Amycolatopsis gen. nov .. In: International Journal of Systematic Bacteriology. Volume 36, No. 1, January 1986, pp. 29-37, ISSN  0020-7713 . doi : 10.1099 / 00207713-36-1-29 .
  2. ↑ a b c d e f g h i j k l Geok Yuan Annie Tan, Michael Goodfellow: Genus V. Amycolatopsis . In: Bergey's Manual of Systematic Bacteriology: Volume 5: The Actinobacteria . 2nd Edition. Springer-Verlag, New York 2012, ISBN 978-0-387-95043-3 , pp. 1334-1358 .
  3. ↑ a b c d e S. K. Tang, Y. Wang u. a .: Amycolatopsis halophila sp. nov., a halophilic actinomycete isolated from a salt lake. In: International journal of systematic and evolutionary microbiology. Volume 60, No. 5, May 2010, pp. 1073-1078, ISSN  1466-5026 . doi : 10.1099 / ijs.0.012427-0 . PMID 19666809 .
  4. ↑ a b c S. D. Lee: Amycolatopsis ultiminotia sp. nov., isolated from rhizosphere soil, and emended description of the genus Amycolatopsis. In: International journal of systematic and evolutionary microbiology. Volume 59, No. 6, June 2009, pp. 1401-1404, ISSN  1466-5026 . doi : 10.1099 / ijs.0.006577-0 . PMID 19502324 .
  5. ↑ a b c A. A. Al-Musallam, SS Al-Zarban a. a .: Amycolatopsis keratiniphila sp. nov., a novel keratinolytic soil actinomycete from Kuwait. In: International journal of systematic and evolutionary microbiology. Volume 53, No. 3, May 2003, pp. 871-874, ISSN  1466-5026 . doi : 10.1099 / ijs.0.02515-0 . PMID 12807215 .
  6. ↑ Taxonomy Browser Amycolatopsis. In: National Center for Biotechnology Information (NCBI) website . Retrieved February 22, 2014 .
  7. ↑ B. Tang, Q. Wang et al. a .: ContigScape: a Cytoscape plugin facilitating microbial genome gap closing. In: BMC genomics. Volume 14, April 2013, p. 289, ISSN  1471-2164 . doi : 10.1186 / 1471-2164-14-289 . PMID 23627759 . PMC 3651407 (free full text).
  8. ↑ a b c Amycolatopsis orientalis. In: National Center for Biotechnology Information (NCBI) Genome website . Retrieved February 22, 2014 .
  9. ↑ a b S. Majumdar, SR Prabhagaran u. a .: Reclassification of Amycolatopsis orientalis DSM 43387 as Amycolatopsis benzoatilytica sp. nov. In: International journal of systematic and evolutionary microbiology. Volume 56, No. 1, January 2006, pp. 199-204, ISSN  1466-5026 . doi : 10.1099 / ijs.0.63766-0 . PMID 16403887 .
  10. ^ A b Jean Euzéby, Aidan C. Parte: Phylum "Actinobacteria". In: List of Prokaryotic names with Standing in Nomenclature ( LPSN ). Retrieved February 20, 2014 .
  11. ↑ a b c d Jean Euzéby, Aidan C. Parte: Genus Amycolatopsis. In: List of Prokaryotic names with Standing in Nomenclature ( LPSN ). Retrieved February 20, 2014 .
  12. ↑ DP Labeda, M. Goodfellow, J. Chun, XY Zhi, WJ Li: Reassessment of the systematics of the suborder Pseudonocardineae: transfer of the genera within the family Actinosynnemataceae Labeda and Kroppenstedt 2000 emend. Zhi et al. 2009 into an emended family Pseudonocardiaceae Embley et al. 1989 emend. Zhi et al. 2009. In: International journal of systematic and evolutionary microbiology. Volume 61, No. 6, June 2011, pp. 1259-1264, ISSN  1466-5034 . doi : 10.1099 / ijs.0.024984-0 . PMID 20601483 .
  13. ↑ S. Warwick, T. Bowen et al. a .: A phylogenetic analysis of the family Pseudonocardiaceae and the genera Actinokineospora and Saccharothrix with 16S rRNA sequences and a proposal to combine the genera Amycolata and Pseudonocardia in an emended genus Pseudonocardia. In: International journal of systematic bacteriology. Vol. 44, No. 2, April 1994, pp. 293-299, ISSN  0020-7713 . doi : 10.1099 / 00207713-44-2-293 . PMID 8186093 .
  14. ↑ a b Joachim M. Wink, Reiner M. Kroppenstedt u. a .: Three New Antibiotic Producing Species of the Genus Amycolatopsis, Amycolatopsis balhimycina sp. nov., A. tolypomycina sp. nov., A. vancoresmycina sp. nov., and Description of Amycolatopsis keratiniphila subsp. keratiniphila subsp. nov. and A. keratiniphila subsp. nogabecina subsp. nov. In: Systematic and Applied Microbiology. Volume 26, No. 1, January 2003, pp. 38-46, ISSN  0723-2020 . doi : 10.1078 / 072320203322337290 .
  15. ↑ L. de Boer, L. Dijkhuizen et al. a .: Amycolatopsis methanolica sp. nov., a facultatively methylotrophic actinomycete. In: International journal of systematic bacteriology. Volume 40, No. 2, April 1990, pp. 194-204, ISSN  0020-7713 . doi : 10.1099 / 00207713-40-2-194 . PMID 2223611 .
  16. ↑ S. Bala, R. Khanna et al. a .: Reclassification of Amycolatopsis mediterranei DSM 46095 as Amycolatopsis rifamycinica sp. nov. In: International journal of systematic and evolutionary microbiology. Vol. 54, No. 4, July 2004, pp. 1145-1149, ISSN  1466-5026 . doi : 10.1099 / ijs.0.02901-0 . PMID 15280283 .