Waikawa deoxyribonucleic. Model Crick ko Watson

Kua tuhia te kōrero tuatahi e pā ana ki te āhuatanga matū o te waikawa deoxyribonucleic 1868 tau. I roto i te rau tau 20 ki te timatanga o nga tekau, i whakamatauria ai e te muingota ko te waerau rārangi. Ka rite ki nucleotides wae waetahi mahi e ngā o te turanga nitrogenous, he pentose me te rōpū Phosphate (he huka e rima-waro).

kia whai deoxyribonucleic te turanga o e rua ngā momo: he pyrimidine (thymine (T) me cytosine (C)) me te purine (adenine (A) me te guanine (G)). kawea te pūhui te i roto i te whakamahi i here nucleotide phosphodiester.

Ōmataora Watson ko Crick i te 1953 tau, tango rite te pūtake mō te tātari X-ray o tioata DNA mutu e ngā te muingota taketake o te rua o nga mekameka polymer, hanga he helix rua. Polynucleotide mekameka marutanga i runga i ia atu, e pupuri tahi i te tikanga o here hauwai e hanga i waenganui i tautoko (tahi hāngai) turanga i roto i te ritenga atu mekameka. A, no te tenei rua i hanga anake e whai ake: adenine-thymine, guanine-cytosine. kawea stabilization i roto i te rua takirua tuatahi, me te tuarua - e toru here hauwai.

Ko te waikawa deoxyribonucleic rua-paea he roa tātai rite te maha o o nucleotides tahi hāngai (BP) takirua. Hoki aua rāpoi ngota, e ngā o miriona me mano o waeine faaipoipo m.n.p. tangohia me kb, aua. Ko te kupu, māngai deoxyribonucleic pūira tangata waikawa e kotahi helix rua. Ko tōna roa ko te 263 Mb i roto i

DNA denaturation (rewa) ko he tukanga ai haere te rāpoi ngota helix rārangi rua auau ki te āhua pōkai. Ki runga ki rewa, e tahuri iho muingota-rua ki taiawhio motuhake. Ko te pāmahana i i rewa hawhe waikawa deoxyribonucleic, he ira whakakoero. Tei te reira i runga i te kounga o te hanganga rāpoi.

Ka rite ki kua whakahuatia i runga ake, kua ähuareka te takirua G-C i toru, me te rua o te-T - rua here hauwai. Nä, ko te teitei te rahi o takirua tuatahi, ka waiho i te atu eu te rāpoi ngota. A, no te denaturation o te roangaru o 260 nm faarahi te absorption o te marama. hanga ana tēnei pānga hyperchromic reira taea ki te whakarato i te mana i runga i te āhua rāpoi o te hanganga tuarua. Ki te te āta te matao o te otinga waikawa whakarewa i waenganui i whenu tautoko o ngā hononga ngoikore taea te hanga e ano, kia waiho he ōrite ki te whenua (taketake) he hanganga tōrino. Tenei kaha o te DNA ki denaturation me rāpoi renaturation hāngai tikanga hybridization. Kei te whakamahia te reira i roto i te haapiiraa i te hanganga o waikawa karihi.

Double-helix rāpoi ngota, he te kawe o te raraunga ira, me te whakatau e rua ngā whakaritenga matua. Tuatahi, kia tāruaruatia reira (tāruatia) ki te tika tiketike, a tuarua, ki te whakawaehere te ariā o ngā rāpoi ngota pūmua. waikawa deoxyribonucleic, kua nei tauira kua whakaahuatia e Watson ko Crick, hāngai tino ki enei whakaritenga. Kei te kitea te reira i e i roto i runga i te parau tumu o te kïnakitanga, ia mekameka i roto i te rāpoi ngota e taea e te kopu mo te hanganga o te ara iahiko tahi hāngai hou. Ka rite ki te hua, kotahi wā o tukuruatanga kupu puta tauhoa rāpoi tamahine he raupapa nucleotide ōrite ki taua i roto i te taketake rāpoi ngota pītauira. Ano, tenei mekameka ira hanganga i roto i te pūmua waikawa amino raupapa whakawaeheretia whakatakoto ana.

Mai, kua rite kua meinga tuwhera DNA tūmatanui, me te parau tumu kïnakitanga, whakapumautia tukanga e he kawenga mō raraunga wetemuna tuku, me te i roto i te ture o ngā matū ira kōtuitanga. I tua atu, ka whakawhanakehia te ariā me te rāpoi recombinant.