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| genus_authority = [[Zopf]] 1891
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'''''Rhodococcus''''' é un xénero de [[bacterias]] [[Gram positiva]]s aeróbicas, non esporulantes, non motís moi relacionadas coas [[micobacteria]]s e as [[CirynebacteriumCorynebacterium|corinebacteria]]s.<ref name=Alice>{{cite journal | author = van der Geize R., and L. Dijkhuizen | title = Harnessing the catabolic diversity of rhodococci for environmental and biotechnological applications | journal = Microbiology | year = 2004 | volume = 7 | pages = 255–261 | url = | pmid=15196492 | issue = 3 | doi = 10.1016/j.mib.2004.04.001}}</ref><ref name= BurkovskiA>{{cite book | author = Burkovski A (editor). | title = Corynebacteria: Genomics and Molecular Biology | publisher = Caister Academic Press | year = 2008 | url=http://www.horizonpress.com/cory | id = [http://www.horizonpress.com/cory ] | isbn = 978-1-904455-30-1}}</ref> Aínda que unhas poucas especies deste xénero son patóxenas, a maioría son benignas e prosperan nunha ampla gama de ambientes, como o solo, auga, e células [[eukarya|eucarióticas]]. O [[xenoma]] foi secuenciado en 2006 e ten 9,7 megapares de bases e un [[contido G/C]] de 67%.<ref name = Betty />
As cepas de ''Rhodococcus'' sonteñen applicablyimportantes importantaplicacións owingdebido toá theirsúa abilitycapacidade tode catabolizecatabolizar aunha wideampla rangevariedade ofde compoundscompostos ande produceproducir bioactive[[esteroide]]s steroidsbioactivos, [[acrylamideacrilamida]], ande [[acrylicácido acidacrílico]], ande a súa theirimplicación involvementna inbiodesulfuración fossilde fuelcombustibles biodesulfurizationfósiles.<ref name=Betty>{{cite journal | doi = 10.1073/pnas.0607048103 | author = McLeod MP, Warren RL, Hsiao WW, Araki N, Myhre M, Fernandes C, Miyazawa D, Wong W, Lillquist AL, Wang D, Dosanjh M, Hara H, Petrescu A, Morin RD, Yang G, Stott JM, Schein JE, Shin H, Smailus D, Siddiqui AS, Marra MA, Jones SJ, Holt R, Brinkman FS, Miyauchi K, Fukuda M, Davies JE, Mohn WW, Eltis LD | title = The complete genome of Rhodococcus sp. RHA1 provides insights into a catabolic powerhouse | journal = PNAS | date = October 17, 2006 | volume = 103 | pages = 15582–15587 | url = | issue=42 | pmid = 17030794 | pmc = 1622865}}</ref> ThisEsta geneticdiversidade andxenética catabolice diversitycatabólica isnon notsó onlyreside dueno tocromosoma thebacteriano large bacterial chromosomegrande, butsenón alsotamén to the presence ofen threetres largegrandes linearplásmidos plasmidsliñais.<ref name = Alice /> ''Rhodococcus'' é istamén alsoun ansistema experimentallyexperimentalmente advantageousvantaxoso systempolas owingsúas totaxas ade relativelycrecemento fastrelativamente growthrápidas ratee ando simplesue developmentalciclo cycle.de However,desenvolvemento as it standssimple. nowPorén, ''Rhodococcus'' isaínda non notestá wellben characterizedcaracterizado.<ref name = Betty />
AnotherOutra importantimportante applicationaplicación ofde ''Rhodococcus'' comesdébese fromá bioconversionsúa bioconversión, usingutilizando biologicalsistemas systemsbiolóxicos topara convertconverter cheapunha startingmateria materialinicial intobarata moreen valuablecompostos compounds.de Thismaior use of ''Rhodococcus'' is borne out of its abilityvalor. toPode metabolizecatabolizar harmfulpolucionantes environmentalambientais pollutantsnocivos, suchcomo aso [[toluenetolueno]], [[naphthalenenafthaleno]], herbicides[[herbicida]]s, ande PCBs[[PCB]]s. Os ''RhodococciRhodococcus'' typicallymetabolizan metabolizetipicamente [[aromatic]]os substratescompostos byaromáticos firstoxixenando oxygenatingprimeiro theo aromaticanel ringaromático topara formformar aun diol (twodous alcoholgrupos groups[[alcohol]]). ThenDespois, the ringclívase iso cleavedanel withpor mecanismos intra/extradiol mechanisms, openingo theanel ringqueda andaberto exposinge theexposto substratea tooutras furthermodificacións metabolism[[metabolismo|metabólicas]]. SinceA thequímica chemistrydestas herereaccións isé verymoi stereospecificestereoespecífica, thepolo diolsque areos createddioles withse predictablecrean chirality.cunha Whilequiralidade controllingpredicible. theUn chiralityexemplo ofdo chemicaluso reactionde presents''Rhodococcus'' a significantpara challengeproducir forunha syntheticmolécula chemists,quiral biologicaldeterminada processesé cana beprodución used instead to faithfully produce chiral molecules in cases where direct chemical synthesis is infeasible or inefficient. An example of this is the use of ''Rhodococcus'' to producede [[indeneindeno]], aun precursor toda thedroga [[AIDSindinavir]] drugusada para tratar a [[indinavirSIDA]], aque proteaseé inhibitor,un andinhibidor da pratease, containinge twocontén ofdous thedos fivecinco chiralcentros centersquirais needednecesarios inpara theeste complexcomplexo.<ref name=Cat>{{cite journal | author = Treadway, S.L., K.S. Yanagimachi, E. Lankenau, P.A. Lessard, G. Stephanopoulos and A.J. Sinskey | title = Isolation and characterization of indene bioconversion genes from Rhodococcus strain I24 | journal = Appl. Microbiol. Biotechnol | year = 1999 | volume = 51 | pmid = 10422226 | pages = 786–793 | url = | doi = 10.1007/s002530051463 | issue=6}}</ref>
[[ImageFicheiro:Crixivan2.gif|leftesquerda|thumbminiatura|450px|Indinavir, indeneco shownindeno inen greenverde.<ref name = Cat />]]
==Biodegradación de contaminantes orgánicos==
==Biodegradation of organic pollutants==
The burgeoning amount of bacterial genomic data provides unparalleled opportunities for understanding the genetic and molecular bases of the [[microbial biodegradation]] of organic [[pollutant]]s. [[Aromatic compounds]] are among the most recalcitrant of these pollutants, and lessons can be learned from the recent genomic studies of ''Rhodococcus jostii'' RHA1, one of the largest bacterial genomes completely sequenced to date. These studies have helped expand the understanding of bacterial [[catabolism]], noncatabolic physiological adaptation to [[organic compound]]s, and the evolution of large bacterial [[genome]]s. A large number of "peripheral aromatic" pathways funnel a range of natural and [[xenobiotic]] compounds into a restricted number of "central aromatic" pathways. Some pathways are more widespread than initially thought. The Box and Paa pathways illustrate the prevalence of nonoxygenolytic ring-cleavage strategies in aerobic aromatic degradation processes. Functional genomic studies have been useful in establishing that even organisms harboring high numbers of homologous enzymes apparently contain few examples of true redundancy. For example, the multiplicity of ring-cleaving dioxygenases in certain rhodococcal isolates may be attributed to the cryptic aromatic catabolism of different terpenoids and steroids. The large gene repertoires of pollutant degraders such as ''Rhodococcus jostii'' RHA1 have evolved principally through more ancient processes.<ref name=chapter1>{{cite book |chapterurl=http://www.horizonpress.com/biod|author=McLeod MP and Eltis LD|year=2008|chapter=Genomic Insights Into the Aerobic Pathways for Degradation of Organic Pollutants|title=Microbial Biodegradation: Genomics and Molecular Biology|publisher=Caister Academic Press|id=[http://www.horizonpress.com/biod |isbn=978-1-904455-17-2]}}</ref> ''Rhodococcus'' sp. strain Q1 (American Type Culture Collection strain number 49987), isolated from soil and paper mill sludge, is able to degrade [[quinoline]], various [[pyridine]] derivatives, [[catechol]], benzoate, and protocatechuic acid.<ref>O'Loughlin, E.J., S.R. Kehrmeyer, and G.K. Sims. 1996. Isolation, characterization, and substrate utilization of a quinoline degrading bacterium. International Biodeterioration and Biodegradation. 38(2):107-118. {{doi|10.1016/S0964-8305(96)00032-7}}</ref>
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