Ukutshintshulwa yintoni?

были описаны в разное время. Ukuguqulwa nokutshintshiselwa kuye kwachazwa ngamaxesha ahlukeneyo. Olu hlobo lokugqibela luvuliwe ngo-1952. Kulesi nqaku siza kuqwalasela ukuba zeziphi iintlobo zokutshintshwa kwezinto ezikhoyo, zeziphi iimpawu abaziphetheyo kunye nalapho kusetshenziswe khona le ngqungquthela.

Izifundo zokuqala

Kwiminyaka yakhe yomfundi uN. Zinder, esebenza kwibhubhoratri yaseLederberg, wayefunda ubukho be-Salmonella typhimurium. Wasebenzisa iingu-20 ze-monaauxotrophic strains. Xa bebabambene ndawonye, isayense yazama ukufumanisa inzala ye-prototrophic. Kwiimeko ezili-9 ezihlanganisiweyo ezingama-79, ii-clones zeeseli zifunyenwe. Ngenxa yokuba akukho nhlobo yeengcambu zokuqala ezakha ababuyiselwa kwi-medium medium, uZinger wagqiba ekubeni ukudibanisa kwenziwa phakathi kwabo, ngeli xesha ulwazi olusasazwa ngalo.

Ukuqinisekisa i-hypothesis, kunye neLederberg, waphinda uvavanyo lukaDavis usebenzisa i-tube efana ne-U ehlukaniswe ngefriji yeglasi engavumelekanga ukuba iinqununu ze-microorganms zidlule. Isifundo sasebenzisa i-Salmonella typhimurium 2Ahis- ne-22Atrp-. Inkcubeko yoxinzelelo lwe-22A yafakwa kwelinye isebe le-tube test, kwelinye i-2A. Bobabini babesesigxina se-1 • iiseli ezili-108 / ml. Emva kwexesha lokuxubusha, inxalenye equlethe i-22A i-strain iveza i-cell prototrophic. Baye baqalwa ngexesha eli-1 • 10-5. Kwesinye isebe le-tube, iiseli ze-prototrophic zazingekho.

Iziphumo zolu vavanyo aluzange ziqinisekise i-hypothesis yokutshintshwa kolwazi lokuxilwa kolwazi kwiinkcenkcesho 22A no-2A.

Utshintsho: Iva

Ngethuba lokuvavanywa kwangaphambili, kwafunyanwa ukuba u-22A unesifo se-P2. Iyakwazi ukusulela kwaye ixilise iiseli ze- Salmonella typhimurium 2A. Ukungena ngefayile, wathintela amangqeleli, wenziwa kwakhona waza wawachitha. Ngethuba elifanayo, i-agent ye-filtering yakhululwa (njengoko uLederberg noZinger babibiza). Naye, wangena ngeglasi. Ngaphantsi kwefuthe le-agent yefayile, ezinye iiseli ezixakeke kwi-22A zifumene iimpawu ezikhethekileyo zobufa. Babefana nalawo ayenakho kwi-2A, apho i-FA yayimfihlo.

Ngokukodwa, ukukwazi ukwenza i-tryptophan kubonisiwe. Kwakumiselwe ukuba umsebenzi we-ejenti yokuhlunga ayilahlekanga ngexesha lonyango kunye ne-DNase yayo. Oku kwasusa ithuba lokuba utshintsho. Kuye kwaqulunqwa ukuba iipropati ze-ejenti yokucoca zifana nezo zipapa P22. Kule nto kwagqitywa ukuba lo mva uthwala ulwazi oluvela kumda we-22A ukuya ku-2A, owenza njengobungqina bendima yefa le-nucleic acids.

UkuTshintshiswa njengengcamango yaziswa ngokubhekiselele kule ngxaki yokudluliswa kwedatha yezofuzo.

Inkqubo ecacileyo

специфичное явление, при котором осуществляется перенос генетической информации от клетки-донора к клетке-реципиенту при помощи фага . UkuTshintshiselwa yinto ethile apho ulwazi lwezofuzo luhanjiswa ukusuka kwiseli yomnikeli ukuya kumnxeba ofumana umbane nge-phage . Isekelwe kwinto yokuba ngexesha lokuphindaphinda kwamaphakheji, iincinci zabo zingazenza. Kanye kunye okanye esikhundleni se-DNA, ziquka ezinye iinqununu kwaye ziye zabizwa ngokuba yi-transducers. Ngokutsho kweempahla zabo ze-adsorption kunye ne-morphology, zifana neziqhelo eziqhelekileyo. Nangona kunjalo, ukuba bachaphazela iiseli ezintsha, iziganeko zemizimba yexesha elidlulileyo liyakudluliselwa. Inkqubo yokutshintshiselwa, ngoko ke, ilandelayo. Ukudluliselwa kwezimpawu zomfuzo, kuyimfuneko ukwandisa isigaba kwiiseli zomnikeli-mali. Emva koko, i-phagolysate ephumela ekubeni ifakwe kumaseli afumana. Ukukhethwa kwamathambo kuthathwa kwimidiya ekhethiweyo. Kuzo, iiseli zangaphambili zamukeli azikwazi ukukhula.

Ukwahlula

Xa ufunda le nkcazo kwafunyanwa ukuba ezinye iiphakheji zinakho ukuhambisa izityalo ezahlukeneyo, ngelixa ezinye - ezikhethekileyo kuphela. Ngokuhambelana nale nto, iindidi ezimbini zokudluliswa kwedatha ziyahlukana:

1. Ukuthunyelwa ngokubanzi . явление предполагает передачу любого фрагмента хромосомы. Le nto ibandakanya ukudluliselwa kwanoma yiyiphi ingqungquthela ye-chromosome.
2. Ukutshintshwa okuthe ngqo. Kule meko, kuphela iizakhi ezithile zegazi ezidluliselwayo.

Inkqubo engapheliyo (jikelele)

Ziziphi iimpawu ezithintekayo kulo mzekelo ? явление имеет место при наличии вируса, выступающего только в качестве переносчика материала. Le nzekayo eyenzekayo phambi kwintsholongwane eyenza nje ukuba ithathe umphathiswa wezinto eziphathekayo. Enye yazo yiphakamiso ekhankanywe ngentla apha P22. ULederberg noZinger basebenze naye. PBS1 B. Subtilis, Р1 E. Coli и проч. Ukongezelela, iiphakheji eziqhutyelwa kuzo zonke iinguqulelo zePBS1 B. i-Subtilis, i-P1 E. Coli njalonjalo. Inkqubo iqhubeka nokuthatha inxaxheba kwiintlobo ezinobuthathaka. Ukubunjwa kwezi zinto kwenzeka ngexesha lokuzaliswa kweephakheji, kunye nokubola kwe-DNA ye-bacterium chromosomal. Kufuneka kuqatshelwe ukuba ukubunjwa kwabo kunokubakho kokubili kwindlela yokuphuhliswa kwabo kwaye emva kokungeniswa kweprojekthi. Inani elithile leengqungquthela ligcwele i-DNA yebhakteria. Ubukhulu beziqhekeza zalo abukho ngaphezu kobukhulu bentloko. Kule meko, iinxalenye ezahlukeneyo ze-chromosome ye-bhakteria zingapakishwa. Iintlobo zeentambo eziphethe iinqununu ze-DNA zibizwa ngeziphene.

Ukugqithiswa

Ukuba i-phagolysate, apho kukho iziqhekeza eziqhelekileyo kunye nezicatshulwayo, phatha iiseli zommkeli, kwaye ukusuleleka kwi-phage eqhelekileyo kukhokelela ekuhlaleni (ukuchithwa). Kodwa ezinye iiseli zichaphazela izixhobo eziphosakeleyo. Izicatshulwa ezifutshane ze-DNA emibini emibini ezivela kumniki-mali zifaka izakhiwo. Ngelo xesha, akukho sitshixo. Ngamanye amazwi, iinqununu eziqhelekileyo ezivela kwi-DNA yomnikeli ziphinde zenze i-DNA evela kummkeli. Le nkqubo ilawulwa yi-recA-gene. Ngaloo ndlela, i-homologous general recombination, eyenziwa ngokutshintshana (ngokubambisana) kunye neengqungquthela ezihambelanayo.

Inkqubo ecacileyo

Ukutshintshwa kwalolu hlobo lufunyenwe ngo-1956. Ubunqabileyo balo kukuba i-phage nganye idlulisela ummandla othile oncinci, we-chromosome. Ukuba isigaba "sihamba" sisithinteli sezinto eziphathekayo, ngoxa i-recombination iyaqhubeka ngokwemigaqo yendawo jikelele, ngoku kungoku kungagqithisi kuphela ulwazi, kodwa kuqinisekisa ukuba kungena kwi-chromosome. Umzekelo ogqwesileyo kakhulu yinkqubo eyenziwa ngophakamiso λ. Iyakwazi ukuthelela ii-E. coli zeeseli ngokudibanisa ngokubanzi kwe-DNA kwi-genome. Le phage echanekileyo kwi-lysogenesis yeebhaktheriya kwi-recombinate-site ethile (ephula kunye nokuwela iinqununu ze-molecule) yakhiwe kwi-chromosome kuphela kwindawo enye-phakathi kwe-bio-gal-loci. Ngokuqinisekileyo, oku kungenxa yokubunjwa "okungalunganga" kwelophu ngexesha lokutshatyalaliswa kolawulo. Ngenxa yoko, ummandla we-genome eduze naso uqhotyoshelwe kwisakhiwo se-chromosome kwaye uba yindawo ekhululekile. Izinto ezifakwe ngaphakathi ziyakwazi ukufaka endaweni ye-1/3 yolwazi lofuzo. Emva kokupakisha i-DNA ye-phage, amaqhekeza angaphiliyo akhiwa.

Izikhokelo zokusetyenziswa

Ukutshintshwa kweebhaktheriya kunokusetyenziswa:

1. Xa kwakhiwa iintlobo ze-genotype ethile, isogenic, ngakumbi. Kule meko, inani elincinci leengqungquthela ezithunyelwayo linika inzuzo kwinkqubo yokutshintshwa ngaphambi kokuba inkqubo yokudibanisa. Iintlobo ze-isogenic ezenziwe ngokuveliswa kwezinto eziphathekayo zihluke kuphela kuloo nxalenye ye-chromosome edluliselwa ngophawu olungapheliyo.
2. Ukujonga ngokuchanekileyo i-gene ye-bhakteria, umise umyalelo wokubekwa kwabo kwii-oonon, isakhiwo esihle sezimiselo ezithile. Oku kwenziwa ngokuhlolwa kovavanyo. Kuye kwaqulunqwa ukuba ukuhlanganiswa kweemveliso ezithile kudinga umsebenzi weezityalo ezininzi. Umzekelo, inkqubo ichongwa ngamacandelo ezakhiwo kunye b. Masithi kukho iinguqu ezi-2 ze-phenotypically ezingafaniyo ezingenakukwazi ukuvelisa i-enzyme. Ayaziwa ukuba ziyahluka njani zemizimba. Ukufumanisa i-genotype, ukutshintshwa kwento yokutshintshwa kwenziwayo, oko kukuthi, ukuphindaphinda kwamaphondo kwiiselingi kubemi abaninzi, kulandelwa ukusuleleka kwimiba yesibini. Ukuba iikoloni ezinkulu kunye ezincinci zentengiso zenziwa kwi-medium selective, kugqitywa ukuba indawo yokuguquka kwimizimba eyahlukileyo.
3. Xa utshintshela i-plasmids kunye neengcezu ezimfutshane zama-chromosomes abanikeli.

Ephakamileyo

Kwakhona iincwadi zihlala zisebenzisa loo mbono ngokuthi "ukutshintshelwa kwempawu". Ingumyalezo wokuthumela. Inkqubo ilandela iphethini ethile. Okokuqala, ummeli wangaphandle udibana ne-receptor yeselula. Emva koko, i-molecule yomshukumisi isebenze. Itholakala kwimbumba kwaye ijongene nokubunjwa kwabaphathi abesekondari. Isizukulwana sabo sikhuthaza ukusetyenziswa kweeprotheni ezijoliswe kuzo. Bona nabo baqalise abalawuli abalandelayo.