ABD’li bir grup ara\u015ft\u0131rmac\u0131, her canl\u0131n\u0131n do\u011fal kal\u0131t\u0131m \u015fifresi olan DNA’y\u0131, yapay yeni eklerle “zenginle\u015ftirmeye” \u00e7al\u0131\u015f\u0131yor. Hedefleri, bu yolla \u015fimdiye de\u011fin do\u011fada hi\u00e7 g\u00f6r\u00fclmemi\u015f proteinler elde etmek. <\/p>\n
Yaln\u0131zca RNA (ribon\u00fckleik asit) ta\u015f\u0131yan baz\u0131 vir\u00fcsler d\u0131\u015f\u0131nda, t\u00fcm canl\u0131 organizmalar, genetik bilgilerini hep ayn\u0131 d\u00f6rt bazdan olu\u015fan, yang\u0131n merdiveni gibi sarmal bi\u00e7imde birle\u015fmi\u015f DNA (deoksiribon\u00fckleik asit) dizelerinde ta\u015f\u0131rlar. Bu bazlar, adenin, timin, sitozin ve guaninden olu\u015fuyor. <\/p>\n
Bunlardan adenin, yaln\u0131zca timin; sitozin de yaln\u0131zca guaninle birle\u015fiyor. Bazlar, kodon ad\u0131 verilen \u00fc\u00e7l\u00fc dizeler olu\u015fturuyor. Her kodon da do\u011fada bulunan 20 amino asitten birini se\u00e7erek protein zincirlerine ekliyor. <\/p>\n
La Jolla’da (California) bulunan Scripps Ara\u015ft\u0131rma Enstit\u00fcs\u00fc molek\u00fcler biyologlar\u0131ndan Floyd Romesberg ba\u015fkanl\u0131\u011f\u0131ndaki ekip, orijinal d\u00f6rt DNA baz\u0131na sentetik yeni bazlar ekleyerek kodon modeli say\u0131s\u0131n\u0131 artt\u0131rmay\u0131 denemi\u015f. <\/p>\n
Ara\u015ft\u0131rmac\u0131lara g\u00f6re bu yeni kodonlar\u0131n yapay amino asitler \u00fcretmeleri, bunlar\u0131n da yepyeni proteinler olu\u015fturmalar\u0131 gerekiyor.Ger\u00e7i do\u011fal olmayan bazlarla yap\u0131lan deneyler, 1980’li y\u0131llara de\u011fin gidiyor; ama \u015fimdiye kadar bunlar\u0131n eklendi\u011fi DNA \u00f6rnekleri hep karars\u0131z duruma d\u00f6n\u00fc\u015fm\u00fc\u015f. <\/p>\n
Romesberg ve ekibiyse, bu engeli a\u015fm\u0131\u015f g\u00f6r\u00fcn\u00fcyor. Ara\u015ft\u0131rmac\u0131lar\u0131n olu\u015fturdu\u011fu 20 yapay baz, t\u0131pk\u0131 do\u011fallar\u0131 gibi \u015fekerlere ba\u011flan\u0131p n\u00fckleosid olu\u015fturmu\u015f. Ekip daha sonra bu yapay bazlardan birini, tek bir DNA \u015feridine eklemi\u015f. DNA’n\u0131n kendini kopyalama s\u00fcrecinde polimeraz denen enzimler, tek \u015ferit halinde dizili kal\u0131plar\u0131 okuyup, gerekli bazlar\u0131 ekleyerek \u00e7iftler olu\u015ftururlar. \u00d6rne\u011fin, adenini timine, sitozini guanine ba\u011flarlar. Do\u011fal olmayan bir bazsa, de\u011fi\u015fik bi\u00e7imde oldu\u011fundan gene de\u011fi\u015fik bir ba\u011f kurar. <\/p>\n
Daha \u00f6nceki ara\u015ft\u0131rmalarda polimerazlar\u0131n bu yapay bazlar\u0131 da gene yapay \u00e7iftlere ba\u011flad\u0131\u011f\u0131 g\u00f6r\u00fclm\u00fc\u015f. Ancak kar\u015f\u0131la\u015f\u0131lan sorun, bu yapay \u00e7iftin, DNA’n\u0131n kopyalanma s\u00fcrecini durdurmas\u0131.Sorunu a\u015fmak i\u00e7in ekip, de\u011fi\u015fik yap\u0131daki polimerazlar\u0131, yapay bazlarla deneyerek sonunda sistemi durdurmadan i\u015fleyen bir model elde etmi\u015f. <\/p>\n
Deney sonunda kopyalama i\u015fleminin, yapay baz \u00e7iftinde kesilmeyerek s\u00fcrd\u00fc\u011f\u00fc g\u00f6r\u00fclm\u00fc\u015f. Ancak, ara\u015ft\u0131rmac\u0131lar s\u0131nama ve yan\u0131lma y\u00f6ntemiyle \u00e7al\u0131\u015ft\u0131klar\u0131ndan s\u00fcre\u00e7 a\u011f\u0131r i\u015fliyor.Ekibin en son amac\u0131, yapay DNA’y\u0131 bakterilere a\u015f\u0131layarak, h\u00fccre etkinliklerini kesintiye u\u011fratmadan yeni kodonlar\u0131n okunup kopyalanmas\u0131n\u0131 sa\u011flamak. Hedef ger\u00e7ekle\u015firse, t\u0131pta ve kimya sanayiinde kullan\u0131labilecek yepyeni proteinler elde edilebilecek. bakal\u0131m yapabileceklermi?<\/p>\n","protected":false},"excerpt":{"rendered":"
ABD’li bir grup ara\u015ft\u0131rmac\u0131, her canl\u0131n\u0131n do\u011fal kal\u0131t\u0131m \u015fifresi olan DNA’y\u0131, yapay yeni eklerle “zenginle\u015ftirmeye” \u00e7al\u0131\u015f\u0131yor. Hedefleri, bu yolla \u015fimdiye de\u011fin do\u011fada hi\u00e7 g\u00f6r\u00fclmemi\u015f proteinler elde etmek. Yaln\u0131zca RNA (ribon\u00fckleik asit) ta\u015f\u0131yan baz\u0131 vir\u00fcsler d\u0131\u015f\u0131nda, t\u00fcm canl\u0131 organizmalar, genetik bilgilerini hep ayn\u0131 d\u00f6rt bazdan olu\u015fan, yang\u0131n merdiveni gibi sarmal bi\u00e7imde birle\u015fmi\u015f DNA (deoksiribon\u00fckleik asit) dizelerinde …<\/p>\n","protected":false},"author":1,"featured_media":0,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"footnotes":""},"categories":[1407,1403],"tags":[2474,2464,2477,6164,2303,2467,2476,2475,6163],"class_list":["post-2444","post","type-post","status-publish","format-standard","hentry","category-fen-ve-teknoloji-odevleri","category-odevler","tag-adenin","tag-deoksiribonukleik-asit","tag-guanin","tag-polimeraz","tag-protein","tag-ribonukleik-asit","tag-sitozin","tag-timin","tag-yapay-dna"],"_links":{"self":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts\/2444","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/comments?post=2444"}],"version-history":[{"count":0,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/posts\/2444\/revisions"}],"wp:attachment":[{"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/media?parent=2444"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/categories?post=2444"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/www.islamidavet.com\/kutuphane\/wp-json\/wp\/v2\/tags?post=2444"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}