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==Overview==
'''''Staphylococcus''''' (from the {{lang-el|σταφυλή}}, ''staphylē'', "grape" and κόκκος, ''kókkos'', "granule") is a genus of [[Gram-positive]] [[Bacterium|bacteria]]. Under the [[microscope]], they appear round ([[cocci]]), and form in [[grape]]-like clusters.<ref name=Sherris>{{cite book | editor = Ryan KJ, Ray CG | title = Sherris Medical Microbiology | edition = 4th | publisher = McGraw Hill | year = 2004 | isbn = 0-8385-8529-9 }}</ref>
The ''Staphylococcus'' [[genus]] includes at least 40 species. Of these, nine have two subspecies and one has three subspecies.<ref name="Harris L.G, Foster S.J 2002">{{cite journal | author = Harris L.G, Foster S.J, Richards S. G. | title = An introduction to Staphylococcus aureus, and techniques for identifying and quantifying S. aureus adhesins in relation to adhesion to biomaterials: review|journal = European cells and materials|volume =4 |pages=39–60| year = 2002 |pmid=14562246|url=http://ecmjournal.org/journal/papers/vol004/pdf/v004a04.pdf}}</ref> Most are harmless and reside normally on the [[skin]] and mucous membranes of humans and other organisms. Found worldwide, they are a small component of soil microbial flora.<ref name=Brock>{{cite book | editor = Madigan M, Martinko J | title = Brock Biology of Microorganisms | edition = 11th | publisher = Prentice Hall | year = 2005 | isbn = 0-13-144329-1 }}</ref>
==Taxonomy==
The taxonomy is based on 16s [[rRNA]] sequences,<ref name="Takahashi1999">{{cite journal|author=Takahashi T, Satoh I, Kikuchi N.|year=1999|title= Phylogenetic relationships of 38 taxa of the genus ''Staphylococcus'' based on 16S rRNA gene sequence analysis|journal= Int. J. Syst. Bacteriol. |volume=49|issue=2|pages= 725–728|pmid=10319495|url=http://ijs.sgmjournals.org/content/49/2/725.full.pdf|doi=10.1099/00207713-49-2-725}}</ref> and most of the staphylococcal species fall into 11 clusters:
#''S. aureus'' group – ''S. aureus'', ''S. simiae''
#''S. auricularis'' group – ''S. auricularis''
#''S. carnosus'' group – ''S. carnosus'', ''S. condimenti'', ''S. massiliensis'', ''S. piscifermentans'', ''S. simulans''
#''S. epidermidis'' group – ''S. capitis'', ''S. caprae'', ''S. epidermidis'', ''S. saccharolyticus''
#''S. haemolyticus'' group – ''S. devriesei'', ''S. haemolyticus'', ''S. hominis''
#''S. hyicus-intermedius'' group – ''S. chromogenes'', ''S. felis'', ''S. delphini'', ''S. hyicus'', ''S. intermedius'', ''S. lutrae'', ''S. microti'', ''S. muscae'', ''S. pseudintermedius'', ''S. rostri'', ''S. schleiferi''
#''S. lugdunensis'' group – ''S. lugdunensis''
#''S. saprophyticus'' group – ''S. arlettae'', ''S. cohnii'', ''S. equorum'', ''S. gallinarum'', ''S. kloosii'', ''S. leei'', ''S. nepalensis'', ''S. saprophyticus'', ''S. succinus'', ''S. xylosus''
#''S. sciuri'' group – ''S. fleurettii'', ''S. lentus'', ''S. sciuri'', ''S. stepanovicii'', ''S. vitulinus''
#''S. simulans'' group – ''S. simulans''
#''S. warneri'' group – ''S. pasteuri'', ''S. warneri''
A twelfth group – that of ''S. caseolyticus'' – has now been moved to a new genus ''[[Macrococcus]]'', the species of which are currently the closest known relatives of the ''Staphylococci''.<ref name="Kloos1998">{{cite journal|author=Kloos WE, Ballard DN, George CG, Webster JA, Hubner RJ, Ludwig W, Schleifer KH, Fiedler F, Schubert K |year=1998|title= Delimiting the genus ''Staphylococcus'' through description of ''Macrococcus caseolyticus'' ''gen. nov.'', ''comb. nov.'' and ''Macrococcus equipercicus'' ''sp. nov., and ''Macrococcus bovicus'' ''sp. nov''. and ''Macrococcus carouselicus'' ''sp. nov''|journal= Int J Syst Bacteriol|volume= 48|issue=3|pages= 859–877|pmid=9734040|url=http://ijs.sgmjournals.org/content/48/3/859.full.pdf|doi=10.1099/00207713-48-3-859}}</ref>


===Subspecies===


==Overview==
''S. aureus'' subsp. ''aureus''<br/>
''S. aureus'' subsp. ''anaerobius''
 
''S. capitis'' subsp. ''capitis''<br/>
''S. capitis'' subsp. ''urealyticus''
 
''S. carnosus'' subsp. ''carnosus''<br/>
''S. carnosus'' subsp. ''utilis''
 
''S. cohnii'' subsp. ''cohnii''<br/>
''S. cohnii'' subsp. ''urealyticus''
 
''S. equorum'' subsp. ''equorum''<br/>
''S. equorum'' subsp. ''linens''
 
''S. hominis'' subsp. ''hominis''<br/>
''S. hominis'' subsp. ''novobiosepticus''
 
''S. saprophyticus'' subsp. ''bovis''<br/>
''S. saprophyticus'' subsp. ''saprophyticus''
 
''S. schleiferi'' subsp. ''coagulans''<br/>
''S. schleiferi'' subsp. ''schleiferi''
 
''S. sciuri'' subsp. ''carnaticus''<br/>
''S. sciuri'' subsp.'' rodentium''<br/>
''S. sciuri'' subsp. ''sciuri''<br/>
 
''S. succinus'' subsp. ''casei''<br/>
''S. succinus'' subsp. ''succinus''
 
===Notes===
 
As with all [[genus|generic]] names in [[binomial nomenclature]], ''Staphylococcus'' is capitalized when used alone or with a specific species. Also, the abbreviations ''Staph'' and ''S.'' when used with a species (''S. aureus'') are correctly italicized and capitalized (though often errors in this are seen in popular literature). However, ''Staphylococcus'' is not capitalized or italicized when used in adjectival forms, as in a staphylococcal infection, or as the plural (staphylococci).<ref>See [http://www.medical-transcription1.com/Articles/eLearnMT/Grammar%20Guidelines%20in%20Transcription/Genus%20&%20Species%20Names.pdf genus and species capitalization.]</ref>
 
The ''S. saprophyticus'' and ''S. sciuri'' groups are generally [[novobiocin]]-resistant, as is ''S. hominis'' subsp. ''novobiosepticus''.
 
Members of the ''S. sciuri'' group are [[oxidase]]-positive due to their possession of the enzyme [[cytochrome c oxidase]]. This group is the only clade within the ''Staphylococci'' to possess this gene.
 
The ''S. sciuri'' group appears to be the closest relations to the genus ''[[Macrococcus]]''.
 
''Staphylococcus pulvereri'' has been shown to be a junior synonym of ''Staphylococcus vitulinus''.<ref name="Svec2004">{{cite journal|author=Svec P., Vancanneyt M., Sedláek I., Engelbeen K., Stetina V., Swings, J. & Petrá, P.|year=2004|title= Reclassification of ''Staphylococcus pulvereri'' Zakrzewska-Czerwiska et al. 1995 as a later synonym of ''Staphylococcus'' vitulinus Webster et al 1994|doi=10.1099/ijs.0.63080-0 |journal= Int. J. Syst. Evol. Microbiol|volume= 54|pages= 2213–2215|issue=6|url=http://ijs.sgmjournals.org/content/54/6/2213.full.pdf|pmid=15545460}}</ref>
 
Within these clades, the ''S. haemolyticus'' and ''S. simulans'' groups appear to be related, as do the ''S. aureus'' and ''S. epidermidis'' groups.<ref name="Ghebremedhin2008">{{cite journal|author=Ghebremedhin B, Layer F, König W, König B |year=2008 |title=Genetic classification and distinguishing of ''Staphylococcus'' species based on different partial gap, 16S rRNA, ''hsp60'', ''rpoB'', ''sodA'', and ''tuf'' gene sequences|journal= J. Clin. Microbiol. |volume=46|issue=3|pages=1019–1025|pmid=18174295|doi=10.1128/JCM.02058-07|pmc=2268370}}</ref>
 
''S. lugdunensis'' appears to be related to the ''S. haemolyticus'' group.
 
''S. croceolyticus'' may be related to ''S. haemolyticus'', but this needs to be confirmed.
 
The taxonomic position of ''S. croceolyticus'', ''S. leei'', ''S. lyticans'' and ''S. pseudolugdunensis'' has yet to be clarified. The published descriptions of these species do not appear to have been validly published to date (2010).
 
==Biochemical identification==
 
Assignment of a strain to the genus ''Staphylococcus'' requires it to be a [[Gram-positive]] [[coccus]] that forms clusters, produces [[catalase]], has an appropriate [[cell wall]] structure (including [[peptidoglycan]] type and teichoic acid presence) and G + C content of DNA in a range of 30–40&nbsp;mol%.
 
''Staphylococcus'' species can be differentiated from other aerobic and facultative anaerobic, Gram-positive cocci by several simple tests. ''Staphylococcus'' [[Species#Abbreviated_names|spp.]] are facultative [[anaerobes]] (capable of growth both aerobically and anaerobically).  All species grow in the presence of [[bile salts]]. 
 
It was believed that all species were coagulase-positive however it is now known that not all ''Staphylococcus'' are coagulase positive.<ref name=Sherris /><ref>PreTest, Surgery, 12th ed., p. 88</ref><ref name="CNSA">{{cite journal | author=Matthews KR, Roberson J, Gillespie BE, Luther DA, Oliver SP | title=Identification and Differentiation of Coagulase-Negative Staphylococcus aureus by Polymerase Chain Reaction | journal=Journal of Food Protection | year=1997 | pages=686–8 | volume=60 | issue=6 |url = http://www.ingentaconnect.com/content/iafp/jfp/1997/00000060/00000006/art00015 }}</ref>
 
Growth can also occur in a 6.5% NaCl solution. On [[Baird-Parker Agar|Baird Parker medium]], ''Staphylococcus'' spp. grow fermentatively, except for ''S. saprophyticus'', which grows oxidatively. ''Staphylococcus'' spp. are resistant to [[bacitracin]] (0.04 U disc: resistance = <&nbsp;10&nbsp;mm zone of inhibition) and susceptible to [[furazolidone]] (100&nbsp;μg disc: resistance = <&nbsp;15&nbsp;mm zone of inhibition). Further biochemical testing is needed to identify to the species level.
 
When the bacterium divides it divides along two axes, so forming clumps of bacteria. This is as opposed to [[streptococci]] which divide along one axis and so form chains (strep. meaning twisted or pliant).
 
===Coagulase production===
 
One of the most important phenotypical features used in the classification of staphylococci is their ability to produce [[coagulase]], an enzyme that causes [[blood clot]] formation.
 
Six species are currently recognised as being coagulase-positive: ''S. aureus'', ''S. delphini'', ''S. hyicus'', ''S. intermedius'', ''S. lutrae'',''S. pseudintermedius'' and ''S. schleiferi'' subsp. ''coagulans''. These species belong to two separate groups – the ''S. aureus'' (''S. aureus'' alone) group and the ''S. hyicus-intermedius'' group (the remaining five). ''S. aureus'' can also be found as being coagulase-negative. 
 
A seventh species has also been described – ''Staphylococcus leei'' – from patients with [[gastritis]].<ref name="Jin2004">{{cite journal|author=Jin M, Rosario W, Watler E, Calhoun DH |year=2004|title= Development of a large-scale HPLC-based purification for the urease from ''Staphylococcus leei'' and determination of subunit structure|journal= Protein Expr. Purif. |volume=34|issue=1|pages=111–117|pmid=14766306|url=http://www.sci.ccny.cuny.edu/chemistry/faculty/calhoun04.pdf|doi=10.1016/j.pep.2003.10.01}}</ref>
''[[Staphylococcus aureus|S. aureus]]'' is coagulase-positive, meaning it produces coagulase. However, while the majority of ''S. aureus'' strains are coagulase-positive, some may be atypical in that they do not produce coagulase. ''S. aureus'' is [[catalase]]-positive (meaning that it can produce the enzyme catalase) and able to convert [[hydrogen peroxide]] (H<sub>2</sub>O<sub>2</sub>) to water and oxygen, which makes the catalase test useful to distinguish staphylococci from [[Enterococcus|enterococci]] and [[Streptococcus|streptococci]].
 
''[[Staphylococcus pseudintermedius|S. pseudintermedius]]'' inhabits and sometimes infects the skin of domestic dogs and cats. This organism, too, can carry the genetic material that imparts multiple bacterial resistance. It is rarely implicated in infections in humans, as a [[zoonosis]].
 
====Coagulase-Negative Staphylococcus====
 
''[[Staphylococcus epidermidis|S. epidermidis]]'', a [[coagulase]]-negative species, is a [[commensal]] of the [[skin]], but can cause severe infections in [[immunosuppression|immune-suppressed]] patients and those with [[central venous catheters]].
 
''[[Staphylococcus saprophyticus|S. saprophyticus]]'', another [[coagulase]]-negative species that is part of the normal [[vaginal flora]], is predominantly implicated in [[genitourinary tract]] infections in sexually active young women.
 
In recent years, several other ''Staphylococcus'' species have been implicated in human infections, notably ''[[Staphylococcus lugdunensis|S. lugdunensis]]'', ''[[Staphylococcus schleiferi|S. schleiferi]]'', and ''[[Staphylococcus caprae|S. caprae]]''.
======Taxonomy of Coagulase-Negative Staphylococci Associated with Human Diseases======
 
* '''''[[Staphylococcus epidermidis]]'''''
 
* '''''[[Staphylococcus haemolyticus]]'''''
 
* '''''[[Staphylococcus lugdunensis]]'''''
 
* '''''[[Staphylococcus saprophyticus]]'''''
 
* ''[[Staphylococcus auricularis]]''
 
* ''[[Staphylococcus capitis]]''
 
* ''[[Staphylococcus caprae]]''
 
* ''[[Staphylococcus carnosus]]''
 
* ''[[Staphylococcus cohnii]]''
 
* ''[[Staphylococcus hominis]]''
 
* ''[[Staphylococcus pasteuri]]''
 
* ''[[Staphylococcus pettenkoferi]]''
 
* ''[[Staphylococcus pulvereri]]''
 
* ''[[Staphylococcus saccharolyticus]]''
 
* ''[[Staphylococcus simulans]]''


'''''Staphylococcus''''' (in Greek ''staphyle'' means ''bunch of grapes'' and ''coccos'' means granule) is a genus of [[Gram-positive]] [[Bacterium|bacteria]]. Under the [[microscope]] they appear round (cocci), and form in grape-like clusters.<ref name=Sherris>{{cite book | author = Ryan KJ, Ray CG (editors) | title = Sherris Medical Microbiology | edition = 4th ed. | publisher = McGraw Hill | year = 2004 | isbn = 0838585299 }}</ref>
* ''[[Staphylococcus schleiferi]]''


The ''Staphylococcus'' [[genus]] includes thirty-one species.<ref name=Holt_1994>{{cite book | author = Holt JG (editor) | title = Bergey's Manual of Determinative Bacteriology | edition = 9th ed. | publisher = Williams & Wilkins | year = 1994 | isbn = 0-683-00603-7 }}</ref> Most are completely harmless, and reside normally on the [[skin]] and mucous membranes of humans and other organisms. Found worldwide, they are a small component of soil microbial flora.<ref name=Brock>{{cite book | author = Madigan M, Martinko J (editors). | title = Brock Biology of Microorganisms | edition = 11th ed. | publisher = Prentice Hall | year = 2005 | isbn = 0131443291 }}</ref>
* ''[[Staphylococcus warneri]]''


==Role in disease==
* ''[[Staphylococcus xylosus]]''


''Staphylococci'' can cause a wide variety of diseases in humans and other animals either through toxin production or invasion. Staphylococcal toxins are a common cause of [[Foodborne illness|food poisoning]] as it can grow in improperly stored food. Although the cooking process kills them, the [[enterotoxin]]s are heat resistant and can survive boiling for several minutes. Staphylococci can grow in foods with relatively low water activity (such as cheese and salami).
==Genomics and molecular biology==


* One [[pathogen]]ic species is ''[[Staphylococcus aureus]]'', which can infect wounds. These bacteria can survive on dry surfaces, increasing the chance of transmission. [[Methicillin-resistant Staphylococcus aureus]] (MRSA) has recently become a major cause of hospital-acquired infections and is being recognized with increasing frequency in community acquired infections. ''S. aureus'' is also implicated in [[toxic shock syndrome]]; during the 1980s some tampons allowed the rapid growth of ''S. aureus'', which released toxins that were absorbed into the bloodstream. Any ''S. aureus'' infection can cause the [[staphylococcal scalded skin syndrome]], a cutaneous reaction to [[exotoxin]] absorbed into the bloodstream. It can also cause a type of [[septicaemia]] called [[pyaemia]].
The first ''S. aureus'' [[genome]]s to be sequenced were those of N315 and Mu50 in 2001. Many more complete ''S. aureus'' genomes have been submitted to the public [[database]]s, making it one of the most extensively sequenced bacteria. The use of genomic data is now widespread and provides a valuable resource for researchers working with ''S. aureus''. Whole genome technologies, such as sequencing projects and [[microarray]]s, have shown an enormous variety of ''S. aureus'' strains. Each contains different combinations of surface proteins and different [[toxin]]s. Relating this information to pathogenic behaviour is one of the major areas of staphylococcal research. The development of molecular typing methods has enabled the tracking of different strains of ''S. aureus''. This may lead to better control of outbreak strains. A greater understanding of how the staphylococci evolve, especially due to the acquisition of mobile genetic elements encoding resistance and virulence genes is helping to identify new outbreak strains and may even prevent their emergence.<ref name=LindsayJ>{{cite book | author = Lindsay J (editor). | title = Staphylococcus: Molecular Genetics | publisher = Caister Academic Press | year = 2008 | url=http://www.horizonpress.com/staph | id = [http://www.horizonpress.com/staph  ] | isbn = 1-904455-29-8}}</ref>


* The [[coagulase]] positive Staphylococcus that inhabits and sometimes infects the skin of domestic dogs and cats is ''Staphylococcus intermedius''. This organism, too, can carry the genetic material that imparts multiple bacterial resistance. It is rarely implicated in infections in humans, as a [[zoonosis]].
The widespread incidence of antibiotic resistance across various strains of ''S. aureus'', or across different species of ''Staphylococcus'' has been attributed to [[horizontal gene transfer]] of genes encoding antibiotic/metal resistance and virulence. A recent study demonstrated the extent of [[horizontal gene transfer]] among ''Staphylococcus'' to be much greater than previously expected, and encompasses genes with functions beyond antibiotic resistance and virulence, and beyond genes residing within the [[mobile genetic elements]].<ref>{{cite journal |author=Chan CX, Beiko RG, Ragan MA |title=Lateral transfer of genes and gene fragments in ''Staphylococcus'' extends beyond mobile elements |journal=J Bacteriol |volume=193 |issue=15 |pages=3964–3977 |year=2011|pmid=21622749 |doi=10.1128/JB.01524-10 |pmc=3147504}}</ref>


* ''[[Staphylococcus epidermidis|S. epidermidis]]'', a [[coagulase]]-negative staphylococcus species, is a commensal of the [[skin]], but can cause severe infections in [[immunosuppression|immune suppressed]] patients and those with [[central venous catheters]].
Various strains of ''Staphylococcus'' are available from biological research centres, such as the [[National Collection of Type Cultures]] (NCTC).


* ''[[Staphylococcus saprophyticus|S. saprophyticus]]'', another [[coagulase]]-negative species that is part of the normal vaginal flora, is predominantly implicated in [[genitourinary tract]] infections in sexually active young women.
==Host range==


* In recent years several other ''Staphylococcus'' species have been implicated in human infections, notably ''[[Staphylococcus lugdunensis|S. lugdunensis]]'', ''S. schleiferi'', and ''[[Staphylococcus caprae|S. caprae]]''.
[[File:20101017 231210 Staphylococcus.jpg|thumb|Unknown variety of ''Staphylococcus'', [[Gram staining|Gram-stained]] - numbered ticks on the scale are 11&nbsp;[[µm]] apart.]]


Staphylococci can also be found on the tips of the fingers.  Most commonly it is found on the index finger as well as the thumb.  This infection is known as a ''felon''. As are many other ''Staphylococcus'' infections, felon is very painful and can be treated with antibiotics. Most ''S. aureus'' are penicillin resistant, but vancomycin and nafcillin are known to be effective against most strains.
Members of the genus ''Staphylococcus'' frequently colonize the skin and upper respiratory tracts of mammals and birds. Some species specificity has been observed in host range, such that the ''Staphylococcus'' species observed on some animals appear more rarely on more distantly related host species.<ref>{{cite journal|author=Kloos WE|year=1980|title= Natural Populations of the Genus ''Staphylococcus''|journal= Annual Review of Microbiology|volume= 34|pages= 559–592|pmid=7002032|doi=10.1146/annurev.mi.34.100180.003015}}</ref>
Some of the observed host specificity includes:


==Biochemical Indentification==
''S. arlattae'' – [[chicken]]s, [[goat]]s<br/>
''S. auricularis'' – [[deer]], [[dog]]s, humans<br/>
''S. capitis'' – humans<br/>
''S. caprae'' – goats, humans<br/>
''S. cohnii'' – chickens, humans<br/>
''S. delphini'' – [[dolphin]]s<br/>
''S. devriesei'' – [[cattle]]<br/>
''S. epidermiditis'' – humans<br/>
''S. equorum'' – [[horse]]s<br/>
''S. felis'' – [[cat]]s<br/>
''S. fleurettii'' – goats<br/>
''S. gallinarum'' – chickens, goats, [[pheasant]]s<br/>
''S. haemolyticus'' – humans, ''[[Cercocebus]]'', ''[[Erythrocebus]]'', ''[[Lemur]]'', ''[[Macca]]'', ''[[Microcebus]]'', ''[[Chimpanzee|Pan]]''<br/>
''S. hyicus'' – [[pig]]s<br/>
''S. leei'' – humans<br/>
''S. lentus'' – goats, [[rabbit]]s, [[sheep]]<br/>
''S. lugdunensis'' – humans, goats<br/>
''S. lutrae'' – [[otter]]s<br/>
''S. microti'' – voles (''[[Microtus arvalis]]'')<br/>
''S. nepalensis'' – goats<br/>
''S. pasteuri'' – humans, goats<br/>
''S. pettenkoferi'' – humans<br/>
''S. pseudintermedius'' – dogs<br/>
''S. rostri'' – [[pig]]s<br/>
''S. schleiferi'' – humans<br/>
''S. sciuri'' – humans, dogs, goats<br/>
''S. simiae'' – South American squirrel monkeys (''[[Saimiri sciureus]]'')<br/>
''S. simulans'' – humans<br/>
''S. warneri'' – humans, [[Cercopithecoidea]], [[Pongidae]]<br/>
''S. xylosus'' – humans


''Staphylococcus aureus'' shows beta-[[hemolysis]] on [[Agar plate#Blood agar types|Sheep Blood Agar]], however ''S. epidermidis'' is non-hemolytic on SBA. Both are positive for [[catalase]] production.
==Clinical==


==Cases==
{{main|Staphylococcal infection}}
''Staphylococcus'' can cause a wide variety of diseases in humans and animals through either toxin production or penetration. Staphylococcal toxins are a common cause of food poisoning, as they can be produced by bacteria growing in improperly stored food items. <br>
The most common [[sialadenitis]] is caused by staphylococci, as bacterial infections.<ref>{{cite news
|url=http://www.doctorhoffman.com/wwsialo.htm
|title=Sialoadenitis: inflammation of the salivary glands
|date=4 January 2001
|publisher=The Medical Consumer's Advocate
|accessdate=2011-01-04}}</ref>


In September and October of 2007, 28 students of 4 high schools in Anne Arundel county Maryland contracted the MRSA string of staph. The schools include Old Mill High School, Severna Park High School, Cheasapeake High School, and Glen Burnie High School,also Southern High School(because of the homecoming game vs the gophers).
==See also==


==References==
*[[Methicillin-resistant Staphylococcus aureus|MRSA]]
<div class="references-small">
*[[Staphylococcal enteritis]]
{{reflist|2}}
*''[[Staphylococcus aureus]]''
</div>
*[[Vancomycin-resistant Staphylococcus aureus|Vancomycin-resistant ''S. aureus'']]
{{clr}}
[[Category:Gram positive bacteria]]
[[Category:Bacillales]]
[[Category:Staphylococcaceae|*]]
[[Category:Dermatology]]


[[Category:Needs content]]


[[ca:Estafilococ]]
==Notes and references==
[[cs:Stafylokok]]
{{Reflist|2}}
[[de:Staphylokokken]]
[[es:Staphylococcus]]
[[fr:Staphylococcus]]
[[ko:포도상구균]]
[[id:Staphylococcus]]
[[it:Stafilococco]]
[[he:Staphylococcus]]
[[nl:Stafylokokken]]
[[ja:ブドウ球菌]]
[[pl:Gronkowce]]
[[pt:Staphylococcus]]
[[ro:Staphylococcus]]
[[sr:Стафилококе]]
[[fi:Staphylococcus]]
[[sv:Staphylokocker]]
[[vi:Tụ cầu khuẩn]]
[[tr:Stafilokoklar]]


== External links ==
* [http://patricbrc.org/portal/portal/patric/Taxon?cType=taxon&cId=1279 Staphylococcus] genomes and related information at [http://patricbrc.org/ PATRIC], a Bioinformatics Resource Center funded by [http://www.niaid.nih.gov/ NIAID]


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Latest revision as of 21:02, 15 January 2014

Staphylococcus
SEM micrograph of S. aureus colonies; note the grape-like clustering common to Staphylococcus species.
SEM micrograph of S. aureus colonies; note the grape-like clustering common to Staphylococcus species.
Scientific classification
Kingdom: Monerans
Phylum: Firmicutes
Class: Bacilli
Order: Bacillales
Family: Staphylococcaceae
Genus: Staphylococcus
Rosenbach 1884
Species

S. afermentans
S. aureus
S. auricularis
S. capitis
S. caprae
S. cohnii
S. epidermidis
S. felis
S. haemolyticus
S. hominis
S. intermedius
S. lugdunensis
S. saprophyticus
S. schleiferi
S. simulans
S. vitulus
S. warneri
S. xylosus

Editor-In-Chief: C. Michael Gibson, M.S., M.D. [2]

Overview

Staphylococcus (from the Template:Lang-el, staphylē, "grape" and κόκκος, kókkos, "granule") is a genus of Gram-positive bacteria. Under the microscope, they appear round (cocci), and form in grape-like clusters.[1]

The Staphylococcus genus includes at least 40 species. Of these, nine have two subspecies and one has three subspecies.[2] Most are harmless and reside normally on the skin and mucous membranes of humans and other organisms. Found worldwide, they are a small component of soil microbial flora.[3]

Taxonomy

The taxonomy is based on 16s rRNA sequences,[4] and most of the staphylococcal species fall into 11 clusters:

  1. S. aureus group – S. aureus, S. simiae
  2. S. auricularis group – S. auricularis
  3. S. carnosus group – S. carnosus, S. condimenti, S. massiliensis, S. piscifermentans, S. simulans
  4. S. epidermidis group – S. capitis, S. caprae, S. epidermidis, S. saccharolyticus
  5. S. haemolyticus group – S. devriesei, S. haemolyticus, S. hominis
  6. S. hyicus-intermedius group – S. chromogenes, S. felis, S. delphini, S. hyicus, S. intermedius, S. lutrae, S. microti, S. muscae, S. pseudintermedius, S. rostri, S. schleiferi
  7. S. lugdunensis group – S. lugdunensis
  8. S. saprophyticus group – S. arlettae, S. cohnii, S. equorum, S. gallinarum, S. kloosii, S. leei, S. nepalensis, S. saprophyticus, S. succinus, S. xylosus
  9. S. sciuri group – S. fleurettii, S. lentus, S. sciuri, S. stepanovicii, S. vitulinus
  10. S. simulans group – S. simulans
  11. S. warneri group – S. pasteuri, S. warneri

A twelfth group – that of S. caseolyticus – has now been moved to a new genus Macrococcus, the species of which are currently the closest known relatives of the Staphylococci.[5]

Subspecies

S. aureus subsp. aureus
S. aureus subsp. anaerobius

S. capitis subsp. capitis
S. capitis subsp. urealyticus

S. carnosus subsp. carnosus
S. carnosus subsp. utilis

S. cohnii subsp. cohnii
S. cohnii subsp. urealyticus

S. equorum subsp. equorum
S. equorum subsp. linens

S. hominis subsp. hominis
S. hominis subsp. novobiosepticus

S. saprophyticus subsp. bovis
S. saprophyticus subsp. saprophyticus

S. schleiferi subsp. coagulans
S. schleiferi subsp. schleiferi

S. sciuri subsp. carnaticus
S. sciuri subsp. rodentium
S. sciuri subsp. sciuri

S. succinus subsp. casei
S. succinus subsp. succinus

Notes

As with all generic names in binomial nomenclature, Staphylococcus is capitalized when used alone or with a specific species. Also, the abbreviations Staph and S. when used with a species (S. aureus) are correctly italicized and capitalized (though often errors in this are seen in popular literature). However, Staphylococcus is not capitalized or italicized when used in adjectival forms, as in a staphylococcal infection, or as the plural (staphylococci).[6]

The S. saprophyticus and S. sciuri groups are generally novobiocin-resistant, as is S. hominis subsp. novobiosepticus.

Members of the S. sciuri group are oxidase-positive due to their possession of the enzyme cytochrome c oxidase. This group is the only clade within the Staphylococci to possess this gene.

The S. sciuri group appears to be the closest relations to the genus Macrococcus.

Staphylococcus pulvereri has been shown to be a junior synonym of Staphylococcus vitulinus.[7]

Within these clades, the S. haemolyticus and S. simulans groups appear to be related, as do the S. aureus and S. epidermidis groups.[8]

S. lugdunensis appears to be related to the S. haemolyticus group.

S. croceolyticus may be related to S. haemolyticus, but this needs to be confirmed.

The taxonomic position of S. croceolyticus, S. leei, S. lyticans and S. pseudolugdunensis has yet to be clarified. The published descriptions of these species do not appear to have been validly published to date (2010).

Biochemical identification

Assignment of a strain to the genus Staphylococcus requires it to be a Gram-positive coccus that forms clusters, produces catalase, has an appropriate cell wall structure (including peptidoglycan type and teichoic acid presence) and G + C content of DNA in a range of 30–40 mol%.

Staphylococcus species can be differentiated from other aerobic and facultative anaerobic, Gram-positive cocci by several simple tests. Staphylococcus spp. are facultative anaerobes (capable of growth both aerobically and anaerobically). All species grow in the presence of bile salts.

It was believed that all species were coagulase-positive however it is now known that not all Staphylococcus are coagulase positive.[1][9][10]

Growth can also occur in a 6.5% NaCl solution. On Baird Parker medium, Staphylococcus spp. grow fermentatively, except for S. saprophyticus, which grows oxidatively. Staphylococcus spp. are resistant to bacitracin (0.04 U disc: resistance = < 10 mm zone of inhibition) and susceptible to furazolidone (100 μg disc: resistance = < 15 mm zone of inhibition). Further biochemical testing is needed to identify to the species level.

When the bacterium divides it divides along two axes, so forming clumps of bacteria. This is as opposed to streptococci which divide along one axis and so form chains (strep. meaning twisted or pliant).

Coagulase production

One of the most important phenotypical features used in the classification of staphylococci is their ability to produce coagulase, an enzyme that causes blood clot formation.

Six species are currently recognised as being coagulase-positive: S. aureus, S. delphini, S. hyicus, S. intermedius, S. lutrae,S. pseudintermedius and S. schleiferi subsp. coagulans. These species belong to two separate groups – the S. aureus (S. aureus alone) group and the S. hyicus-intermedius group (the remaining five). S. aureus can also be found as being coagulase-negative.

A seventh species has also been described – Staphylococcus leei – from patients with gastritis.[11]

S. aureus is coagulase-positive, meaning it produces coagulase. However, while the majority of S. aureus strains are coagulase-positive, some may be atypical in that they do not produce coagulase. S. aureus is catalase-positive (meaning that it can produce the enzyme catalase) and able to convert hydrogen peroxide (H2O2) to water and oxygen, which makes the catalase test useful to distinguish staphylococci from enterococci and streptococci.

S. pseudintermedius inhabits and sometimes infects the skin of domestic dogs and cats. This organism, too, can carry the genetic material that imparts multiple bacterial resistance. It is rarely implicated in infections in humans, as a zoonosis.

Coagulase-Negative Staphylococcus

S. epidermidis, a coagulase-negative species, is a commensal of the skin, but can cause severe infections in immune-suppressed patients and those with central venous catheters.

S. saprophyticus, another coagulase-negative species that is part of the normal vaginal flora, is predominantly implicated in genitourinary tract infections in sexually active young women.

In recent years, several other Staphylococcus species have been implicated in human infections, notably S. lugdunensis, S. schleiferi, and S. caprae.

Taxonomy of Coagulase-Negative Staphylococci Associated with Human Diseases

Genomics and molecular biology

The first S. aureus genomes to be sequenced were those of N315 and Mu50 in 2001. Many more complete S. aureus genomes have been submitted to the public databases, making it one of the most extensively sequenced bacteria. The use of genomic data is now widespread and provides a valuable resource for researchers working with S. aureus. Whole genome technologies, such as sequencing projects and microarrays, have shown an enormous variety of S. aureus strains. Each contains different combinations of surface proteins and different toxins. Relating this information to pathogenic behaviour is one of the major areas of staphylococcal research. The development of molecular typing methods has enabled the tracking of different strains of S. aureus. This may lead to better control of outbreak strains. A greater understanding of how the staphylococci evolve, especially due to the acquisition of mobile genetic elements encoding resistance and virulence genes is helping to identify new outbreak strains and may even prevent their emergence.[12]

The widespread incidence of antibiotic resistance across various strains of S. aureus, or across different species of Staphylococcus has been attributed to horizontal gene transfer of genes encoding antibiotic/metal resistance and virulence. A recent study demonstrated the extent of horizontal gene transfer among Staphylococcus to be much greater than previously expected, and encompasses genes with functions beyond antibiotic resistance and virulence, and beyond genes residing within the mobile genetic elements.[13]

Various strains of Staphylococcus are available from biological research centres, such as the National Collection of Type Cultures (NCTC).

Host range

File:20101017 231210 Staphylococcus.jpg
Unknown variety of Staphylococcus, Gram-stained - numbered ticks on the scale are 11 µm apart.

Members of the genus Staphylococcus frequently colonize the skin and upper respiratory tracts of mammals and birds. Some species specificity has been observed in host range, such that the Staphylococcus species observed on some animals appear more rarely on more distantly related host species.[14] Some of the observed host specificity includes:

S. arlattae – chickens, goats
S. auricularis – deer, dogs, humans
S. capitis – humans
S. caprae – goats, humans
S. cohnii – chickens, humans
S. delphini – dolphins
S. devriesei – cattle
S. epidermiditis – humans
S. equorum – horses
S. felis – cats
S. fleurettii – goats
S. gallinarum – chickens, goats, pheasants
S. haemolyticus – humans, Cercocebus, Erythrocebus, Lemur, Macca, Microcebus, Pan
S. hyicus – pigs
S. leei – humans
S. lentus – goats, rabbits, sheep
S. lugdunensis – humans, goats
S. lutrae – otters
S. microti – voles (Microtus arvalis)
S. nepalensis – goats
S. pasteuri – humans, goats
S. pettenkoferi – humans
S. pseudintermedius – dogs
S. rostri – pigs
S. schleiferi – humans
S. sciuri – humans, dogs, goats
S. simiae – South American squirrel monkeys (Saimiri sciureus)
S. simulans – humans
S. warneri – humans, Cercopithecoidea, Pongidae
S. xylosus – humans

Clinical

Main article: Staphylococcal infection

Staphylococcus can cause a wide variety of diseases in humans and animals through either toxin production or penetration. Staphylococcal toxins are a common cause of food poisoning, as they can be produced by bacteria growing in improperly stored food items.
The most common sialadenitis is caused by staphylococci, as bacterial infections.[15]

See also

Notes and references

  1. ↑ 1.0 1.1 Ryan KJ, Ray CG, ed. (2004). Sherris Medical Microbiology (4th ed.). McGraw Hill. ISBN 0-8385-8529-9.
  2. ↑ Harris L.G, Foster S.J, Richards S. G. (2002). "An introduction to Staphylococcus aureus, and techniques for identifying and quantifying S. aureus adhesins in relation to adhesion to biomaterials: review" (PDF). European cells and materials. 4: 39–60. PMID 14562246.
  3. ↑ Madigan M, Martinko J, ed. (2005). Brock Biology of Microorganisms (11th ed.). Prentice Hall. ISBN 0-13-144329-1.
  4. ↑ Takahashi T, Satoh I, Kikuchi N. (1999). "Phylogenetic relationships of 38 taxa of the genus Staphylococcus based on 16S rRNA gene sequence analysis" (PDF). Int. J. Syst. Bacteriol. 49 (2): 725–728. doi:10.1099/00207713-49-2-725. PMID 10319495.
  5. ↑ Kloos WE, Ballard DN, George CG, Webster JA, Hubner RJ, Ludwig W, Schleifer KH, Fiedler F, Schubert K (1998). "Delimiting the genus Staphylococcus through description of Macrococcus caseolyticus gen. nov., comb. nov. and Macrococcus equipercicus sp. nov., and Macrococcus bovicus sp. nov. and Macrococcus carouselicus sp. nov" (PDF). Int J Syst Bacteriol. 48 (3): 859–877. doi:10.1099/00207713-48-3-859. PMID 9734040.
  6. ↑ See genus and species capitalization.
  7. ↑ Svec P., Vancanneyt M., Sedláek I., Engelbeen K., Stetina V., Swings, J. & Petrá, P. (2004). "Reclassification of Staphylococcus pulvereri Zakrzewska-Czerwiska et al. 1995 as a later synonym of Staphylococcus vitulinus Webster et al 1994" (PDF). Int. J. Syst. Evol. Microbiol. 54 (6): 2213–2215. doi:10.1099/ijs.0.63080-0. PMID 15545460.
  8. ↑ Ghebremedhin B, Layer F, König W, König B (2008). "Genetic classification and distinguishing of Staphylococcus species based on different partial gap, 16S rRNA, hsp60, rpoB, sodA, and tuf gene sequences". J. Clin. Microbiol. 46 (3): 1019–1025. doi:10.1128/JCM.02058-07. PMC 2268370. PMID 18174295.
  9. ↑ PreTest, Surgery, 12th ed., p. 88
  10. ↑ Matthews KR, Roberson J, Gillespie BE, Luther DA, Oliver SP (1997). "Identification and Differentiation of Coagulase-Negative Staphylococcus aureus by Polymerase Chain Reaction". Journal of Food Protection. 60 (6): 686–8.
  11. ↑ Jin M, Rosario W, Watler E, Calhoun DH (2004). "Development of a large-scale HPLC-based purification for the urease from Staphylococcus leei and determination of subunit structure" (PDF). Protein Expr. Purif. 34 (1): 111–117. doi:10.1016/j.pep.2003.10.01. PMID 14766306.
  12. ↑ Lindsay J (editor). (2008). Staphylococcus: Molecular Genetics. Caister Academic Press. ISBN 1-904455-29-8. [1].
  13. ↑ Chan CX, Beiko RG, Ragan MA (2011). "Lateral transfer of genes and gene fragments in Staphylococcus extends beyond mobile elements". J Bacteriol. 193 (15): 3964–3977. doi:10.1128/JB.01524-10. PMC 3147504. PMID 21622749.
  14. ↑ Kloos WE (1980). "Natural Populations of the Genus Staphylococcus". Annual Review of Microbiology. 34: 559–592. doi:10.1146/annurev.mi.34.100180.003015. PMID 7002032.
  15. ↑ "Sialoadenitis: inflammation of the salivary glands". The Medical Consumer's Advocate. 4 January 2001. Retrieved 2011-01-04.

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