Mycoplasma: Difference between revisions
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== Origin of the name == |
== Origin of the name == |
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The name ''Mycoplasma'', from the Greek ''mykes'' (fungus) and ''plasma'' (formed), was first used by A. B. Frank in 1889. He thought it was a fungus, due to fungus-like characteristics |
The name ''Mycoplasma'', from the Greek ''mykes'' (fungus) and ''plasma'' (formed), was first used by A. B. Frank in 1889. He thought it was a fungus, due to fungus-like characteristics.<ref name="Krass_1973">{{cite journal | author = Krass CJ, Gardner MW | title = | journal = Int. J. of Syst. Bact. | volume = 23 | issue = 1 | pages = 62-64 | year = 1973 | month = January | pmid = | doi = | url = http://ijs.sgmjournals.org/cgi/reprint/23/1/62.pdf }}</ref> |
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.<ref>Conrad J. Krass and Max W. Gardner [http://ijs.sgmjournals.org/cgi/reprint/23/1/62.pdf ''Etymology of the Term Mycoplasma''] Int. J. of Syst. Bact.; Jan 1973, p. 62-64; Vol. 23, No. 1</ref> |
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An older name for ''Mycoplasma'' was '''Pleuropneumonia-Like Organisms''' (PPLO), referring to organisms similar to the causative agent of [[contagious bovine pleuropneumonia]] (CBPP).<ref name=Edward>{{cite journal |author=Edward DG, Freundt EA |title=The classification and nomenclature of organisms of the pleuropneumonia group |journal=J. Gen. Microbiol. |volume=14 |issue=1 |pages=197–207 |year=1956 |month=February |pmid=13306904 |doi= |url= |
An older name for ''Mycoplasma'' was '''Pleuropneumonia-Like Organisms''' (PPLO), referring to organisms similar to the causative agent of [[contagious bovine pleuropneumonia]] (CBPP).<ref name="Edward">{{cite journal | author = Edward DG, Freundt EA | title = The classification and nomenclature of organisms of the pleuropneumonia group | journal = J. Gen. Microbiol. | volume = 14 | issue = 1 | pages = 197–207 | year = 1956 | month = February | pmid = 13306904 | doi = | url = http://mic.sgmjournals.org/cgi/reprint/14/1/197.pdf }}</ref> It was later found that the fungus-like growth pattern of ''M. mycoides'' is unique to that species. |
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== Characteristics == |
== Characteristics == |
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== First isolation == |
== First isolation == |
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In 1898 Nocard and Roux reported the cultivation of the causative agent of CBPP, which was at that time a grave and widespread disease in cattle herds.<ref>Nocard, E. |
In 1898 Nocard and Roux reported the cultivation of the causative agent of CBPP, which was at that time a grave and widespread disease in cattle herds.<ref name="Nocard_Roux_1898">{{cite journal | author = Nocard EIE , Roux E | title = The microbe of pleuropneumonia. 1896 | journal = Rev. Infect. Dis. | volume = 12 | issue = 2 | pages = 354–8 | year = 1990 | pmid = 2184501 | quote = translation of ''Le microbe de la péripneumonie.'' Ann Inst Pasteur '''12''', 240-262, 1898 | url = }}</ref><ref name="Hayflick">{{cite journal | author = Hayflick L, [[Robert M. Chanock|Chanock RM]] | title = Mycoplasma Species of Man | journal = Bacteriol Rev | volume = 29 | issue = | pages = 185–221 | year = 1965 | month = June | pmid = 14304038 | pmc = 441270 | doi = }}</ref> The disease is caused by ''[[Mycoplasma mycoides|M. mycoides]]'' subsp. mycoides SC (small-colony type), and the work of Nocard and Roux represented the first isolation of a mycoplasma species. Cultivation was, and still is difficult because of the complex growth requirements. |
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These researchers succeeded by inoculating a semi-permeable pouch of sterile medium with pulmonary fluid from an infected animal and depositing this pouch intraperitoneally into a live rabbit. After fifteen to twenty days, the fluid inside of the recovered pouch was opaque, indicating the growth of a microorganism. Opacity of the fluid was not seen in the control. This turbid broth could then be used to inoculate a second and third round and subsequently introduced into a healthy animal, causing disease. However, this did not work if the material was heated, indicating a biological agent at work. Uninoculated media in the pouch, after removal from the rabbit, could be used to grow the organism [[in vitro]], demonstrating the possibility of cell-free cultivation and ruling out viral causes, although this was not fully appreciated at the time |
These researchers succeeded by inoculating a semi-permeable pouch of sterile medium with pulmonary fluid from an infected animal and depositing this pouch intraperitoneally into a live rabbit. After fifteen to twenty days, the fluid inside of the recovered pouch was opaque, indicating the growth of a microorganism. Opacity of the fluid was not seen in the control. This turbid broth could then be used to inoculate a second and third round and subsequently introduced into a healthy animal, causing disease. However, this did not work if the material was heated, indicating a biological agent at work. Uninoculated media in the pouch, after removal from the rabbit, could be used to grow the organism [[in vitro]], demonstrating the possibility of cell-free cultivation and ruling out viral causes, although this was not fully appreciated at the time .<ref name="Nocard_Roux_1898"/> |
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== Small genome == |
== Small genome == |
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Recent advances in [[molecular biology]] and [[genomics]] have brought the genetically simple mycoplasmas, particularly ''M. pneumoniae'' and its close relative ''[[Mycoplasma genitalium|M. genitalium]]'', to a larger audience. The second published complete bacterial genome sequence was that of ''M. genitalium'', which has one of the smallest genomes of free-living organisms.<ref name=Fraser>{{cite journal |author=Fraser CM, Gocayne JD, White O, |
Recent advances in [[molecular biology]] and [[genomics]] have brought the genetically simple mycoplasmas, particularly ''M. pneumoniae'' and its close relative ''[[Mycoplasma genitalium|M. genitalium]]'', to a larger audience. The second published complete bacterial genome sequence was that of ''M. genitalium'', which has one of the smallest genomes of free-living organisms.<ref name="Fraser">{{cite journal | author = Fraser CM, Gocayne JD, White O, Adams MD, Clayton RA, Fleischmann RD, Bult CJ, Kerlavage AR, Sutton G, Kelley JM, Fritchman RD, Weidman JF, Small KV, Sandusky M, Fuhrmann J, Nguyen D, Utterback TR, Saudek DM, Phillips CA, Merrick JM, Tomb JF, Dougherty BA, Bott KF, Hu PC, Lucier TS, Peterson SN, Smith HO, Hutchison CA, Venter JC | title = The minimal gene complement of Mycoplasma genitalium | journal = Science | volume = 270 | issue = 5235 | pages = 397–403 | year = 1995 | month = October | pmid = 7569993 | doi = 10.1126/science.270.5235.397 }}</ref> The ''M. pneumoniae'' genome sequence was published soon afterwards and was the first genome sequence determined by [[primer walking]] of a [[cosmid]] library instead of the [[whole-genome shotgun]] method.<ref name="pmid8948633">{{cite journal | author = Himmelreich R, Hilbert H, Plagens H, Pirkl E, Li BC, Herrmann R | title = Complete sequence analysis of the genome of the bacterium Mycoplasma pneumoniae | journal = Nucleic Acids Res. | volume = 24 | issue = 22 | pages = 4420–49 | year = 1996 | month = November | pmid = 8948633 | pmc = 146264 | doi = 10.1093/nar/24.22.4420 }}</ref> ''Mycoplasma'' genomics and [[proteomics]] continue in efforts to understand the |
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so-called [[mycoplasma laboratorium|minimal cell]],<ref>{{cite book | author = Hutchison CA, Montague MG | chapter = Mycoplasmas and the minimal genome concept | |
so-called [[mycoplasma laboratorium|minimal cell]],<ref name="isbn0-306-47287-2">{{cite book | author = Hutchison CA, Montague MG | chapter = Mycoplasmas and the minimal genome concept | editor = Razin S, Herrmann R | title = Molecular biology and pathogenicity of mycoplasmas | publisher = Kluwer Academic/Plenum | location = New York | year = 2002 | pages = | isbn = 0-306-47287-2 }}</ref> catalog the entire protein content of a cell,<ref name="pmid11271496">{{cite journal | author = Regula JT, Ueberle B, Boguth G, Görg A, Schnölzer M, Herrmann R, Frank R | title = Towards a two-dimensional proteome map of Mycoplasma pneumoniae | journal = Electrophoresis | volume = 21 | issue = 17 | pages = 3765–80 | year = 2000 | month = November | pmid = 11271496 | doi = 10.1002/1522-2683(200011)21:17<3765::AID-ELPS3765>3.0.CO;2-6 }}</ref> and generally continue to take advantage of the small genome of these organisms to understand broad biological concepts. |
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== Taxonomy == |
== Taxonomy == |
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The pneumoniae group contains the clusters of ''[[Mycoplasma muris|M. muris]]'', ''[[Mycoplasma fastidiosum|M. fastidiosum]]'', ''[[Ureaplasma urealyticum|U. urealyticum]]'', the currently unculturable [[haemotrophic mollicutes]], informally referred to as [[haemoplasmas]] (recently transferred from the genera ''Haemobartonella'' and ''Eperythrozoon''), and the ''M. pneumoniae'' cluster. This cluster contains the species (and the usual or likely host) ''[[Mycoplasma alvi|M. alvi]]'' (bovine), ''[[Mycoplasma amphoriforme|M. amphoriforme]]'' (human), ''[[Mycoplasma gallisepticum|M. gallisepticum]]'' (avian), ''[[Mycoplasma genitalium|M. genitalium]]'' (human), ''[[Mycoplasma imitans|M. imitans]]'' (avian), ''[[Mycoplasma pirum|M. pirum]]'' (uncertain/human), ''[[Mycoplasma testudinis|M. testudinis]]'' (tortoises), and ''[[Mycoplasma pneumoniae|M. pneumoniae]]'' (human). Most if not all of these species share some otherwise unique characteristics including an attachment organelle, homologs of the ''M. pneumoniae'' cytadherence-accessory proteins, and specialized modifications of the cell division apparatus. |
The pneumoniae group contains the clusters of ''[[Mycoplasma muris|M. muris]]'', ''[[Mycoplasma fastidiosum|M. fastidiosum]]'', ''[[Ureaplasma urealyticum|U. urealyticum]]'', the currently unculturable [[haemotrophic mollicutes]], informally referred to as [[haemoplasmas]] (recently transferred from the genera ''Haemobartonella'' and ''Eperythrozoon''), and the ''M. pneumoniae'' cluster. This cluster contains the species (and the usual or likely host) ''[[Mycoplasma alvi|M. alvi]]'' (bovine), ''[[Mycoplasma amphoriforme|M. amphoriforme]]'' (human), ''[[Mycoplasma gallisepticum|M. gallisepticum]]'' (avian), ''[[Mycoplasma genitalium|M. genitalium]]'' (human), ''[[Mycoplasma imitans|M. imitans]]'' (avian), ''[[Mycoplasma pirum|M. pirum]]'' (uncertain/human), ''[[Mycoplasma testudinis|M. testudinis]]'' (tortoises), and ''[[Mycoplasma pneumoniae|M. pneumoniae]]'' (human). Most if not all of these species share some otherwise unique characteristics including an attachment organelle, homologs of the ''M. pneumoniae'' cytadherence-accessory proteins, and specialized modifications of the cell division apparatus. |
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A study of 143 genes in 15 species of ''Mycoplasma'' suggests that the genus can be grouped into four clades: the ''M. hyopneumoniae'' group, the ''M. mycoides'' group, the ''M. pneumoniae'' group and a ''Bacillus''-''Phytoplasma'' group.<ref>Oshima K, Nishida H |
A study of 143 genes in 15 species of ''Mycoplasma'' suggests that the genus can be grouped into four clades: the ''M. hyopneumoniae'' group, the ''M. mycoides'' group, the ''M. pneumoniae'' group and a ''Bacillus''-''Phytoplasma'' group.<ref name="pmid17687503">{{cite journal | author = Oshima K, Nishida H | title = Phylogenetic relationships among mycoplasmas based on the whole genomic information | journal = J. Mol. Evol. | volume = 65 | issue = 3 | pages = 249–58 | year = 2007 | month = September | pmid = 17687503 | doi = 10.1007/s00239-007-9010-3 }}</ref> The ''M. hyopneumoniae'' group is more closely related to the ''M. pneumoniae'' group than the ''M. mycoides'' group. |
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== Laboratory contaminant == |
== Laboratory contaminant == |
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It has been estimated that at least 11 to 15% of U.S. laboratory cells cultures are contaminated with mycoplasma.{{Who|date=March 2011}} |
It has been estimated that at least 11 to 15% of U.S. laboratory cells cultures are contaminated with mycoplasma.{{Who|date=March 2011}} |
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A [[Corning Incorporated|Corning]] study showed that half of U.S. scientists did not test for mycoplasma contamination in their cell cultures. The study also stated that, in Czechoslovakia, 100% of cell cultures that were not routinely tested were contaminated while only 2% of those routinely tested were contaminated. (study page 6) Since the U.S. contamination rate was based on a study of companies that routinely checked for mycoplasma, the actual contamination rate may be higher. European contamination rates are higher and that of other countries are higher still (up to 80% of Japanese cell cultures).<ref name=Corning>{{cite news | author = John Ryan | title = Understanding and Managing Cell Culture Contamination | pages= 24 |edition = | publisher = Corning Incorporated | year = 2008 | url = http://catalog2.corning.com/Lifesciences/media/pdf/cccontamination.pdf}}</ref> |
A [[Corning Incorporated|Corning]] study showed that half of U.S. scientists did not test for mycoplasma contamination in their cell cultures. The study also stated that, in Czechoslovakia, 100% of cell cultures that were not routinely tested were contaminated while only 2% of those routinely tested were contaminated. (study page 6) Since the U.S. contamination rate was based on a study of companies that routinely checked for mycoplasma, the actual contamination rate may be higher. European contamination rates are higher and that of other countries are higher still (up to 80% of Japanese cell cultures).<ref name=Corning>{{cite news | author = John Ryan | title = Understanding and Managing Cell Culture Contamination | pages= 24 |edition = | publisher = Corning Incorporated | year = 2008 | url = http://catalog2.corning.com/Lifesciences/media/pdf/cccontamination.pdf}}</ref> |
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About 1% of published Gene Expression Omnibus data may have been compromised.<ref name=Astarloa:2009:BT>{{cite |
About 1% of published Gene Expression Omnibus data may have been compromised.<ref name="Astarloa:2009:BT">{{cite journal | author = Aldecoa-Otalora E, Langdon WB, Cunningham P, Arno MJ | title = Unexpected presence of mycoplasma probes on human microarrays | journal = BioTechniques | volume = 47 | issue = 6 | pages = 1013–5 | year = 2009 | month = December | pmid = 20047202 | doi = 10.2144/000113271 }}</ref><ref name="wlangdon">[http://bioinformatics.essex.ac.uk/users/wlangdon/rnanet/scatter.html#1570561_at.pm1,1570561_at.pm3 Link] into RNAnet showing contamination of GEO. Press plot and drag blue crosshairs to expose links to description of experiments on human RNA samples)</ref> Several antibiotic based formulation of anti-mycoplasma reagents have been developed over the years.<ref name="anti-mycoplasma reagents">[http://www.roche-applied-science.com/proddata/gpip/3_5_3_2_5_1.html BM-Cyclin] by Roche, MRA by ICN, [http://www.invivogen.com/plasmocin Plasmocin] by Invivogen and more recently [http://www.de-plasma.com/Technical.html De-Plasma] by TOKU-E.</ref> |
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([http://bioinformatics.essex.ac.uk/users/wlangdon/rnanet/scatter.html#1570561_at.pm1,1570561_at.pm3 Link] into RNAnet showing contamination of GEO. Press plot and drag blue crosshairs to expose links to description of experiments on human RNA samples). Several antibiotic based formulation of anti-mycoplasma reagents have been developed over the years, including [http://www.roche-applied-science.com/proddata/gpip/3_5_3_2_5_1.html BM-Cyclin] by Roche, MRA by ICN, [http://www.invivogen.com/plasmocin Plasmocin] by Invivogen and more recently [http://www.de-plasma.com/Technical.html De-Plasma] by TOKU-E. |
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== Synthetic mycoplasma genome == |
== Synthetic mycoplasma genome == |
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A chemically synthesized genome of a mycoplasmal cell based entirely on synthetic DNA which can self-replicate has been created.<ref name="pmid20488990">{{cite journal | author = Gibson DG, Glass JI, Lartigue C, Noskov VN, Chuang RY, Algire MA, Benders GA, Montague MG, Ma L, Moodie MM, Merryman C, Vashee S, Krishnakumar R, Assad-Garcia N, Andrews-Pfannkoch C, Denisova EA, Young L, Qi ZQ, Segall-Shapiro TH, Calvey CH, Parmar PP, Hutchison CA, Smith HO, Venter JC | title = Creation of a bacterial cell controlled by a chemically synthesized genome | journal = Science | volume = 329 | issue = 5987 | pages = 52–6 | year = 2010 | month = July | pmid = 20488990 | doi = 10.1126/science.1190719 }}</ref> |
A chemically synthesized genome of a mycoplasmal cell based entirely on synthetic DNA which can self-replicate has been created.<ref name="pmid20488990">{{cite journal | author = Gibson DG, Glass JI, Lartigue C, Noskov VN, Chuang RY, Algire MA, Benders GA, Montague MG, Ma L, Moodie MM, Merryman C, Vashee S, Krishnakumar R, Assad-Garcia N, Andrews-Pfannkoch C, Denisova EA, Young L, Qi ZQ, Segall-Shapiro TH, Calvey CH, Parmar PP, Hutchison CA, Smith HO, Venter JC | title = Creation of a bacterial cell controlled by a chemically synthesized genome | journal = Science | volume = 329 | issue = 5987 | pages = 52–6 | year = 2010 | month = July | pmid = 20488990 | doi = 10.1126/science.1190719 }}</ref> |
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Revision as of 05:05, 16 October 2011
| Mycoplasma | |
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| Scientific classification | |
| Kingdom: | |
| Phylum: | |
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| Order: | |
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| Genus: | Mycoplasma Nowak 1929
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| Species | |
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M. gallisepticum | |
| Mycoplasma |
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Mycoplasma refers to a genus of bacteria that lack a cell wall.[1] Without a cell wall, they are unaffected by many common antibiotics such as penicillin or other beta-lactam antibiotics that target cell wall synthesis. They can be parasitic or saprotrophic. Several species are pathogenic in humans, including M. pneumoniae, which is an important cause of atypical pneumonia and other respiratory disorders, and M. genitalium, which is believed to be involved in pelvic inflammatory diseases.
Origin of the name
The name Mycoplasma, from the Greek mykes (fungus) and plasma (formed), was first used by A. B. Frank in 1889. He thought it was a fungus, due to fungus-like characteristics.[2]
An older name for Mycoplasma was Pleuropneumonia-Like Organisms (PPLO), referring to organisms similar to the causative agent of contagious bovine pleuropneumonia (CBPP).[3] It was later found that the fungus-like growth pattern of M. mycoides is unique to that species.
Characteristics
There are over 100 recognized species of the genus Mycoplasma, one of several genera within the bacterial class Mollicutes. Mollicutes are parasites or commensals of humans, other animals (including insects), and plants; the genus Mycoplasma is by definition restricted to vertebrate hosts. Cholesterol is required for the growth of species of the genus Mycoplasma as well as certain other genera of mollicutes. Their optimum growth temperature is often the temperature of their host if warmbodied (e. g. 37° C in humans) or ambient temperature if the host is unable to regulate its own internal temperature. Analysis of 16S ribosomal RNA sequences as well as gene content strongly suggest that the mollicutes, including the mycoplasmas, are closely related to either the Lactobacillus or the Clostridium branch of the phylogenetic tree (Firmicutes sensu stricto).
Cell morphology
The bacteria of the genus Mycoplasma (trivial name: mycoplasmas) and their close relatives are characterized by lack of a cell wall. Despite this, the cells often present a certain shape, with a characteristic small size, with typically about 10% of the volume of an Escherichia coli cell. These cell shapes presumably contribute to the ability of mycoplasmas to thrive in their respective environments. Most are pseudococcoidal, but there are notable exceptions. Species of the M. fastidiosum cluster are rod-shaped. Species of the M. pneumoniae cluster, including M. pneumoniae, possess a polar extension protruding from the pseudococcoidal cell body. This tip structure, designated an attachment organelle or terminal organelle, is essential for adherence to host cells and for movement along solid surfaces (gliding motility), and is implicated in normal cell division. M. pneumoniae cells are pleomorphic, with an attachment organelle of regular dimensions at one pole and a trailing filament of variable length and uncertain function at the other end, whereas other species in the cluster typically lack the trailing filament. Other species like M. mobile and M. pulmonis have similar structures with similar functions.
Mycoplasmas are unusual among bacteria in that most require sterols for the stability of their cytoplasmic membrane. Sterols are acquired from the environment, usually as cholesterol from the animal host. Mycoplasmas generally possess a relatively small genome of 0.58-1.38 megabases, which results in drastically reduced biosynthetic capabilities and explains their dependence on a host. Additionally they use an alternate genetic code where the codon UGA is encoding for the amino acid tryptophan instead of the usual opal stop codon. They have a low GC-content (23-40 mol %).
First isolation
In 1898 Nocard and Roux reported the cultivation of the causative agent of CBPP, which was at that time a grave and widespread disease in cattle herds.[4][5] The disease is caused by M. mycoides subsp. mycoides SC (small-colony type), and the work of Nocard and Roux represented the first isolation of a mycoplasma species. Cultivation was, and still is difficult because of the complex growth requirements.
These researchers succeeded by inoculating a semi-permeable pouch of sterile medium with pulmonary fluid from an infected animal and depositing this pouch intraperitoneally into a live rabbit. After fifteen to twenty days, the fluid inside of the recovered pouch was opaque, indicating the growth of a microorganism. Opacity of the fluid was not seen in the control. This turbid broth could then be used to inoculate a second and third round and subsequently introduced into a healthy animal, causing disease. However, this did not work if the material was heated, indicating a biological agent at work. Uninoculated media in the pouch, after removal from the rabbit, could be used to grow the organism in vitro, demonstrating the possibility of cell-free cultivation and ruling out viral causes, although this was not fully appreciated at the time .[4]
Small genome
Recent advances in molecular biology and genomics have brought the genetically simple mycoplasmas, particularly M. pneumoniae and its close relative M. genitalium, to a larger audience. The second published complete bacterial genome sequence was that of M. genitalium, which has one of the smallest genomes of free-living organisms.[6] The M. pneumoniae genome sequence was published soon afterwards and was the first genome sequence determined by primer walking of a cosmid library instead of the whole-genome shotgun method.[7] Mycoplasma genomics and proteomics continue in efforts to understand the so-called minimal cell,[8] catalog the entire protein content of a cell,[9] and generally continue to take advantage of the small genome of these organisms to understand broad biological concepts.
Taxonomy
The medical and agricultural importance of members of the genus Mycoplasma and related genera has led to the extensive cataloging of many of these organisms by culture, serology, and small subunit rRNA gene and whole genome sequencing. A recent focus in the sub-discipline of molecular phylogenetics has both clarified and confused certain aspects of the organization of the class Mollicutes.[10]
Originally the trivial name "mycoplasmas" has commonly denoted all members of the class Mollicutes. The name "Mollicutes" is derived from the Latin mollis (soft) and cutes (skin), and all of these bacteria do lack a cell wall and the genetic capability to synthesize peptidoglycan. Now Mycoplasma is a genus in Mollicutes. Despite the lack of a cell wall, many taxonomists have classified Mycoplasma and relatives in the phylum Firmicutes, consisting of low G+C Gram-positive bacteria such as Clostridium, Lactobacillus, and Streptococcus based on 16S rRNA gene analysis. The order Mycoplasmatales contains a single family, Mycoplasmataceae, comprising two genera: Mycoplasma and Ureaplasma.
Historically, the description of a bacterium lacking a cell wall was sufficient to classify it to the genus Mycoplasma and as such it is the oldest and largest genus of the class with about half of the class' species (107 validly described), each usually limited to a specific host and with many hosts harboring more than one species, some pathogenic and some commensal. In later studies, many of these species were found to be phylogenetically distributed among at least three separate orders.
A limiting criterion for inclusion within the genus Mycoplasma is that the organism have a vertebrate host. In fact, the type species, M. mycoides, along with other significant mycoplasma species like M. capricolum, is evolutionarily more closely related to the genus Spiroplasma in the order Entomoplasmatales than to the other members of the Mycoplasma genus. This and other discrepancies will likely remain unresolved because of the extreme confusion that change could engender among the medical and agricultural communities.
The remaining species in the genus Mycoplasma are divided into three non-taxonomic groups, hominis, pneumoniae and fermentans, based on 16S rRNA gene sequences.
The hominis group contains the phylogenetic clusters of M. bovis, M. pulmonis, and M. hominis, among others. M. hyopneumoniae is a primary bacterial agent of the porcine respiratory disease complex.
The pneumoniae group contains the clusters of M. muris, M. fastidiosum, U. urealyticum, the currently unculturable haemotrophic mollicutes, informally referred to as haemoplasmas (recently transferred from the genera Haemobartonella and Eperythrozoon), and the M. pneumoniae cluster. This cluster contains the species (and the usual or likely host) M. alvi (bovine), M. amphoriforme (human), M. gallisepticum (avian), M. genitalium (human), M. imitans (avian), M. pirum (uncertain/human), M. testudinis (tortoises), and M. pneumoniae (human). Most if not all of these species share some otherwise unique characteristics including an attachment organelle, homologs of the M. pneumoniae cytadherence-accessory proteins, and specialized modifications of the cell division apparatus.
A study of 143 genes in 15 species of Mycoplasma suggests that the genus can be grouped into four clades: the M. hyopneumoniae group, the M. mycoides group, the M. pneumoniae group and a Bacillus-Phytoplasma group.[11] The M. hyopneumoniae group is more closely related to the M. pneumoniae group than the M. mycoides group.
Laboratory contaminant
Mycoplasma species are often found in research laboratories as contaminants in cell culture. Mycoplasmal cell culture contamination occurs due to contamination from individuals or contaminated cell culture medium ingredients[clarification needed][citation needed]. Mycoplasma cells are physically small – less than 1 µm – and they are therefore difficult to detect with a conventional microscope. Mycoplasmas may induce cellular changes, including chromosome aberrations, changes in metabolism and cell growth. Severe Mycoplasma infections may destroy a cell line. Detection techniques include DNA Probe, enzyme immunoassays, PCR, plating on sensitive agar and staining with a DNA stain including DAPI or Hoechst.
It has been estimated that at least 11 to 15% of U.S. laboratory cells cultures are contaminated with mycoplasma.[who?] A Corning study showed that half of U.S. scientists did not test for mycoplasma contamination in their cell cultures. The study also stated that, in Czechoslovakia, 100% of cell cultures that were not routinely tested were contaminated while only 2% of those routinely tested were contaminated. (study page 6) Since the U.S. contamination rate was based on a study of companies that routinely checked for mycoplasma, the actual contamination rate may be higher. European contamination rates are higher and that of other countries are higher still (up to 80% of Japanese cell cultures).[12] About 1% of published Gene Expression Omnibus data may have been compromised.[13][14] Several antibiotic based formulation of anti-mycoplasma reagents have been developed over the years.[15]
Synthetic mycoplasma genome
A chemically synthesized genome of a mycoplasmal cell based entirely on synthetic DNA which can self-replicate has been created.[16]
See also
References
- ^ Ryan KJ, Ray CG (editors) (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. pp. 409–12. ISBN 0838585299.
{{cite book}}:|author=has generic name (help) - ^ Krass CJ, Gardner MW (1973). Int. J. of Syst. Bact. 23 (1): 62–64 http://ijs.sgmjournals.org/cgi/reprint/23/1/62.pdf.
{{cite journal}}: Missing or empty|title=(help); Unknown parameter|month=ignored (help) - ^ Edward DG, Freundt EA (1956). "The classification and nomenclature of organisms of the pleuropneumonia group" (PDF). J. Gen. Microbiol. 14 (1): 197–207. PMID 13306904.
{{cite journal}}: Unknown parameter|month=ignored (help) - ^ a b Nocard EIE , Roux E (1990). "The microbe of pleuropneumonia. 1896". Rev. Infect. Dis. 12 (2): 354–8. PMID 2184501.
translation of Le microbe de la péripneumonie. Ann Inst Pasteur 12, 240-262, 1898
- ^ Hayflick L, Chanock RM (1965). "Mycoplasma Species of Man". Bacteriol Rev. 29: 185–221. PMC 441270. PMID 14304038.
{{cite journal}}: Unknown parameter|month=ignored (help) - ^ Fraser CM, Gocayne JD, White O, Adams MD, Clayton RA, Fleischmann RD, Bult CJ, Kerlavage AR, Sutton G, Kelley JM, Fritchman RD, Weidman JF, Small KV, Sandusky M, Fuhrmann J, Nguyen D, Utterback TR, Saudek DM, Phillips CA, Merrick JM, Tomb JF, Dougherty BA, Bott KF, Hu PC, Lucier TS, Peterson SN, Smith HO, Hutchison CA, Venter JC (1995). "The minimal gene complement of Mycoplasma genitalium". Science. 270 (5235): 397–403. doi:10.1126/science.270.5235.397. PMID 7569993.
{{cite journal}}: Unknown parameter|month=ignored (help)CS1 maint: multiple names: authors list (link) - ^ Himmelreich R, Hilbert H, Plagens H, Pirkl E, Li BC, Herrmann R (1996). "Complete sequence analysis of the genome of the bacterium Mycoplasma pneumoniae". Nucleic Acids Res. 24 (22): 4420–49. doi:10.1093/nar/24.22.4420. PMC 146264. PMID 8948633.
{{cite journal}}: Unknown parameter|month=ignored (help)CS1 maint: multiple names: authors list (link) - ^ Hutchison CA, Montague MG (2002). "Mycoplasmas and the minimal genome concept". In Razin S, Herrmann R (ed.). Molecular biology and pathogenicity of mycoplasmas. New York: Kluwer Academic/Plenum. ISBN 0-306-47287-2.
- ^ Regula JT, Ueberle B, Boguth G, Görg A, Schnölzer M, Herrmann R, Frank R (2000). "Towards a two-dimensional proteome map of Mycoplasma pneumoniae". Electrophoresis. 21 (17): 3765–80. doi:10.1002/1522-2683(200011)21:17<3765::AID-ELPS3765>3.0.CO;2-6. PMID 11271496.
{{cite journal}}: Unknown parameter|month=ignored (help)CS1 maint: multiple names: authors list (link) - ^ Johansson K-E, Pettersson B (2002). "Taxonomy of Mollicutes". Molecular Biology and Pathogenicity of Mycoplasmas (Razin S, Herrmann R, eds.). New York: Kluwer Academic/Plenum. pp. 1–30. ISBN 0306472872.
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{{cite journal}}: Unknown parameter|month=ignored (help) - ^ John Ryan (2008). "Understanding and Managing Cell Culture Contamination" (PDF). Corning Incorporated. p. 24.
- ^ Aldecoa-Otalora E, Langdon WB, Cunningham P, Arno MJ (2009). "Unexpected presence of mycoplasma probes on human microarrays". BioTechniques. 47 (6): 1013–5. doi:10.2144/000113271. PMID 20047202.
{{cite journal}}: Unknown parameter|month=ignored (help)CS1 maint: multiple names: authors list (link) - ^ Link into RNAnet showing contamination of GEO. Press plot and drag blue crosshairs to expose links to description of experiments on human RNA samples)
- ^ BM-Cyclin by Roche, MRA by ICN, Plasmocin by Invivogen and more recently De-Plasma by TOKU-E.
- ^ Gibson DG, Glass JI, Lartigue C, Noskov VN, Chuang RY, Algire MA, Benders GA, Montague MG, Ma L, Moodie MM, Merryman C, Vashee S, Krishnakumar R, Assad-Garcia N, Andrews-Pfannkoch C, Denisova EA, Young L, Qi ZQ, Segall-Shapiro TH, Calvey CH, Parmar PP, Hutchison CA, Smith HO, Venter JC (2010). "Creation of a bacterial cell controlled by a chemically synthesized genome". Science. 329 (5987): 52–6. doi:10.1126/science.1190719. PMID 20488990.
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External links
- Bionique Testing Laboratories, Inc. Mycoplasma resources, technical articles and testing kits.
- Compare the size of these small bacteria to the sizes of other cells and viruses.
- MedPix(r)Images Mycoplasma Pneumonia
- Ureaplasma Infection: eMedicine Infectious Diseases
- Antibiotics formulation for eradication of mycoplasma in cell culture media.
- Mycoplasma elimination and prevention in cell culture
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