Brevibacterium linens: Difference between revisions

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===Higher order taxa===
===Higher order taxa===


Bacteria; Actinobacteria; Actinobacteria; Actinobacteridae; Actinomycetales; Micrococcineae; Brevibacteriaceae; Brevibacterium
Bacteria; Actinobacteria; Actinobacteria; Actinobacteridae; Actinomycetales; Micrococcineae; Brevibacteriaceae; Brevibacterium <sup>[2]</sup>
[[File:Brevibacteriumlinens.jpg|800px|thumb|right|Structure of ''linens''<sup>[5]</sup>]]
===Species===


===Species===
Species (''linens'')
Species (linens)


''Brevibacterium linens''
''Brevibacterium linens''


==Description and significance==
==Description and significance==
[[File:File.png|200px|thumb|left|alt text]]
[[File:Romadur.jpg|600px|thumb|left|Romadur cheese <sup>[6]</sup>]]
Rahnella aquatilis is a relatively rare gram-negative rod-shaped bacteria which has been found in fresh water, soil, certain animals such as snails [5] and certain beetles, [4] and isolated human clinical specimens. [2]  This bacterium is of importance because of its abundance and its disease-causing ability in humans. Many different strains have been isolated, and presumably more will be disocvered.
 
''B.linens'' cell wall contains teichoic acids which have neutral sugars, amino sugars, and sugar alcohols. This provides support to the cell wall<sup>[1]</sup>. It is heterogeneous and consists of at least 2 DNA-DNA homology groups. It grows well on peptone-yeast extract media. In order to see the color pigment of ''B.linens'' at some point the media needs to be exposed to light<sup>[1]</sup>.
 
''Brevibacterium linens'' is found in soil but what makes it unique to other ''Brevibacterium'' is that it is also found on human skin, more specifically our feet <sup>[4]</sup>. It causes foot odor.  
 
Another thing that makes it unique is that it is found in cheeses. It was first isolated from romadur cheese in Germany<sup>[4]</sup>. Other cheese surfaces it is on are Munster, Brick, Tilsiter, and Appenzeller<sup>[3]</sup>.
 
 
 
 
 
 
 
 


==Genome structure==
==Genome structure==
As of the year 2000, at least 70 strains of Rahnella aquatilis have been identified [1].  According to the National Center for Biotechnology Information (NCBI), the whole genome has been sequenced for R. aquatilis Strain Y9602.  This particular strain has a genome consisting of 4,864,217 basepairs, with two identified plasmids [2]. Another strain, Rahnella aquatilis CUETM 77-115, was shown to have a genome consisting of 5,440,269 basepairs, and had a G-C content of 52.1% [3].
 
[[File:Linensgenome.png]]
 
''Brevibacterium linens'' has a linear genome with 4,366,969 base pairs. There are 2,741,031 G+C base pairs, making up 63% of the genome<sup>[4]</sup>. The picture above shows a partial sequence of the genome. Each color represents different types of transport genes and the direction of gene sequence on the genome <sup>[4]</sup>.


==Cell and colony structure==
==Cell and colony structure==
Rahnella aquatilis is gram-negative rod-shaped bacterium, about 2-3 microns in length. Strain ISL 19 was isolated from soybean rhizosphere, and was seen to have several flagella for motility [6]. The bacterium can be readily cultured in the laboratory.  
 
''Brevibacterium linens'' are gram positive, rod-shaped colonies <sup>[4]</sup>. When looking under the microscope it exhibits a rod coccus shape on the media but as the cells enter stationary phase they become coccoid shaped <sup>[3]</sup>. Both of these shapes are gram positive but some of the strains can decolorize easily <sup>[3]</sup>. They are non-motile and aerobic. These colonies have a pH range of 5.5-9.5. It is halo-tolerant and non sporing.


==Metabolism==
==Metabolism==
Rahnella aquatilis is a facultative anaerobe (it can live in the absence or presence of oxygen) that fixes Nitrogen [2]. R. aquatilis metabolizing whey lactose produces high levels of organic acids (except for lactic acid) [7].      
 
''Brevibacterium linens'' is obligately aerobic. It is catalase positive and oxidative towards sugars. It is able to hyrdolyze casein, gelatin, and milk<sup>[1]</sup>. 
 
''B.linens'' plays a big role in the metabolism of cheeses. The ripening of the cheese goes from a yeast and mold flora to a bacterial flora <sup>[3]</sup>. The yeast uses the lactate in the curd for energy, increasing the pH, allowing growth of ''B.linens''. These cheeses are high in salt concentration with allows only halotolerant microorganisms to grow on the surface of the cheese<sup>[3]</sup>.
 
 
 
==Ecology== 
 
''Brevibacterium linens'' does not have any endospore formation and is nonmotile. The temperature range is mesophilic, however the optimum temperature for growth is 20-30&deg;C <sup>[4]</sup>. It is found in places with high salt concentration.
 
There have been some isolations of ''Brevibacterium'' from marine fish and sea water that seem to be an orange pigment strain that is considered to be very similiar to ''B.linens''<sup>[1]</sup>.  


==Ecology==
Rahnella aquatilis is named so because of its prevalence in fresh water.  It has been found around the globe in places like the United States, Korea, Japan, Russia, the Ukraine, and Egypt.  R. aquatilis has also been found in humans, soil,  and snails [5]. One of the most unusual places for the the microbe to have been found was inside the gut of certain speicies of longicorn beetles in Korea [4].




==Pathology==
==Pathology==
Rahnella aquatilis is pathogenic in humans.  The organism can be diagnosed in patients via blood cultures, respiratory washings, and in wound cultures.  Various infections, such as bacteremia (from renal infection), sepsis, respiratory infection, and urinary tract infection can be the result.  One case involved an 11-month-old girl with congenital heart disease who developed infective endocarditis [8].  Another case involved a 76-year-old male who had prostatic hyperplasia presenting with acute pyelonephritis [9]. It is noted that R. aquatilis can potentially cause life-threatening infections in humans, infants and adults alike, especially the immunocompromised and organ transplant recipients.  Treatments have included intravenous and oral levofloxacin therapy (and other members of the quinolone family).
There are no known pathogens with this bacteria, however there are some known pathogens with different species in the genus ''Brevibacterium''<sup>[1]</sup>.  


==References==
[1] Collins, Matthew. "The Genus ''Brevibacterium''". ''Prokaryotes'', Volume 3, 2006, pages 1013-1019.


==References==
[2] NCBI. U.S. National Library of Medicine. <http://www.ncbi.nlm.nih.gov/>  
[1] NCBI. U.S. National Library of Medicine. <http://www.ncbi.nlm.nih.gov/>  


[2] Rattray, Fergal P., and Patrick F. Fox. "Aspects of Enzymology and Biochemical Properties of Brevibacterium Linens Relevant to Cheese Ripening." Journal of Dairy Science, Volume 82, 1999, Pages 891-909.
[3] Rattray, Fergal P., and Patrick F. Fox. "Aspects of Enzymology and Biochemical Properties of Brevibacterium Linens Relevant to Cheese Ripening." ''Journal of Dairy Science'', Volume 82, 1999, Pages 891-909.
   
   
[3] Sorhaug, Terje, and John Ordal. "Cell-Bound Lipase and Esterase of Brevibacterium Linens." Applied Microbiology, Volume 25, 1974, Pages 607-608.
[4] JGI. DOE Joint Genome Institute. <http://img.jgi.doe.gov/cgi-bin/w/main.cgi?section=TaxonDetail&taxon_oid=638341022#>
 
 


[5]Leary, Heather. The Microscopy Facility. <http://bioweb.usu.edu/microscopy/Research.htm>


[6]The refined world of cheese. <http://pro-cheese.ru/romadur.html>


Edited by Brittany Harlow, student of Dr. Lisa R. Moore, University of Southern Maine, Department of Biological Sciences, http://www.usm.maine.edu/bio
Edited by Brittany Harlow, student of Dr. Lisa R. Moore, University of Southern Maine, Department of Biological Sciences, http://www.usm.maine.edu/bio

Latest revision as of 02:25, 18 May 2013

This student page has not been curated.

A Microbial Biorealm page on the genus Brevibacterium linens

Classification

Higher order taxa

Bacteria; Actinobacteria; Actinobacteria; Actinobacteridae; Actinomycetales; Micrococcineae; Brevibacteriaceae; Brevibacterium [2]

Structure of linens[5]

Species

Species (linens)

Brevibacterium linens





Description and significance

Romadur cheese [6]

B.linens cell wall contains teichoic acids which have neutral sugars, amino sugars, and sugar alcohols. This provides support to the cell wall[1]. It is heterogeneous and consists of at least 2 DNA-DNA homology groups. It grows well on peptone-yeast extract media. In order to see the color pigment of B.linens at some point the media needs to be exposed to light[1].

Brevibacterium linens is found in soil but what makes it unique to other Brevibacterium is that it is also found on human skin, more specifically our feet [4]. It causes foot odor.

Another thing that makes it unique is that it is found in cheeses. It was first isolated from romadur cheese in Germany[4]. Other cheese surfaces it is on are Munster, Brick, Tilsiter, and Appenzeller[3].





Genome structure

Linensgenome.png

Brevibacterium linens has a linear genome with 4,366,969 base pairs. There are 2,741,031 G+C base pairs, making up 63% of the genome[4]. The picture above shows a partial sequence of the genome. Each color represents different types of transport genes and the direction of gene sequence on the genome [4].

Cell and colony structure

Brevibacterium linens are gram positive, rod-shaped colonies [4]. When looking under the microscope it exhibits a rod coccus shape on the media but as the cells enter stationary phase they become coccoid shaped [3]. Both of these shapes are gram positive but some of the strains can decolorize easily [3]. They are non-motile and aerobic. These colonies have a pH range of 5.5-9.5. It is halo-tolerant and non sporing.

Metabolism

Brevibacterium linens is obligately aerobic. It is catalase positive and oxidative towards sugars. It is able to hyrdolyze casein, gelatin, and milk[1].

B.linens plays a big role in the metabolism of cheeses. The ripening of the cheese goes from a yeast and mold flora to a bacterial flora [3]. The yeast uses the lactate in the curd for energy, increasing the pH, allowing growth of B.linens. These cheeses are high in salt concentration with allows only halotolerant microorganisms to grow on the surface of the cheese[3].


Ecology

Brevibacterium linens does not have any endospore formation and is nonmotile. The temperature range is mesophilic, however the optimum temperature for growth is 20-30°C [4]. It is found in places with high salt concentration.

There have been some isolations of Brevibacterium from marine fish and sea water that seem to be an orange pigment strain that is considered to be very similiar to B.linens[1].


Pathology

There are no known pathogens with this bacteria, however there are some known pathogens with different species in the genus Brevibacterium[1].

References

[1] Collins, Matthew. "The Genus Brevibacterium". Prokaryotes, Volume 3, 2006, pages 1013-1019.

[2] NCBI. U.S. National Library of Medicine. <http://www.ncbi.nlm.nih.gov/>

[3] Rattray, Fergal P., and Patrick F. Fox. "Aspects of Enzymology and Biochemical Properties of Brevibacterium Linens Relevant to Cheese Ripening." Journal of Dairy Science, Volume 82, 1999, Pages 891-909.

[4] JGI. DOE Joint Genome Institute. <http://img.jgi.doe.gov/cgi-bin/w/main.cgi?section=TaxonDetail&taxon_oid=638341022#>

[5]Leary, Heather. The Microscopy Facility. <http://bioweb.usu.edu/microscopy/Research.htm>

[6]The refined world of cheese. <http://pro-cheese.ru/romadur.html>

Edited by Brittany Harlow, student of Dr. Lisa R. Moore, University of Southern Maine, Department of Biological Sciences, http://www.usm.maine.edu/bio