{"id":504,"date":"2023-06-27T22:03:29","date_gmt":"2023-06-27T20:03:29","guid":{"rendered":"https:\/\/clankomat.cz\/?p=504"},"modified":"2023-06-27T22:03:30","modified_gmt":"2023-06-27T20:03:30","slug":"vedci-objevili-slozku-rna-ve-vzorcich-z-asteroidu-ryugu","status":"publish","type":"post","link":"https:\/\/clankomat.cz\/?p=504","title":{"rendered":"V\u011bdci objevili slo\u017eku RNA ve vzorc\u00edch z asteroidu Ryugu"},"content":{"rendered":"\n<p>Anal\u00fdza vzork\u016f odebran\u00fdch z asteroidu Ryugu sondou Hayabusa2 uk\u00e1zala p\u0159\u00edtomnost uracilu, kter\u00fd je sou\u010d\u00e1st\u00ed nukleotid\u016f RNA. Ve vzorc\u00edch byly nalezeny i molekuly vitaminu B3. Tato zji\u0161t\u011bn\u00ed poskytuj\u00ed dal\u0161\u00ed <a href=\"https:\/\/www.star-media.cz\/\">d\u016fkaz<\/a>, \u017ee d\u016fle\u017eit\u00e9 stavebn\u00ed kameny \u017eivota mohly b\u00fdt na Zemi doru\u010deny meteority.<\/p>\n\n\n\n<p>Ran\u00e1 Zem\u011b byla velmi nep\u0159\u00e1telsk\u00e9 m\u00edsto, n\u011bkdy dost hork\u00e9, aby roztrhalo molekuly nezbytn\u00e9 pro \u017eivot. To vyvol\u00e1v\u00e1 z\u0159ejmou ot\u00e1zku, odkud se vzaly stavebn\u00ed kameny \u017eivota, kdy\u017e planeta chladla? Jasnou odpov\u011bd\u00ed jsou asteroidy a komety.<\/p>\n\n\n\n<p><strong>Panspermie<\/strong><\/p>\n\n\n\n<p>My\u0161lenka, \u017ee \u017eivot, respektive jeho stavebn\u00ed kameny, existuje v kosmu a je distribuov\u00e1n mezi planety, hv\u011bzdy a dokonce i galaxie pomoc\u00ed asteroid\u016f, komet, meteoroid\u016f a asteroid\u016f, se naz\u00fdv\u00e1 panspermie. Samotn\u00fd pojem v\u0161ak p\u016fvod \u017eivota nevysv\u011btluje. Hovo\u0159\u00ed o mo\u017enosti jeho \u0161\u00ed\u0159en\u00ed kolem planet \u010di galaxi\u00ed r\u016fzn\u00fdmi objekty ve vesm\u00edru.<\/p>\n\n\n\n<p>Po\u010d\u00e1tky tohoto konceptu lze hledat u \u0159eck\u00e9ho filozofa Anaxagora, ale jeho rozkv\u011bt s mnoha variantami spad\u00e1 na 19. a 20. stolet\u00ed. Tato hypot\u00e9za nabyla na s\u00edle, kdy\u017e byly v meteoritech nalezeny n\u011bkter\u00e9 dus\u00edkat\u00e9 b\u00e1ze, kter\u00e9 pom\u00e1haj\u00ed tvo\u0159it DNA a RNA. Tyto chemik\u00e1lie jsou stavebn\u00edmi kameny \u017eivota.<\/p>\n\n\n\n<p>Studie prachu dodan\u00e9ho na na\u0161i planetu sondou Hayabusa2 Japonsk\u00e9 vesm\u00edrn\u00e9 agentury (JAXA) p\u0159id\u00e1v\u00e1 dal\u0161\u00ed d\u016fkaz, \u017ee stavebn\u00ed kameny \u017eivota mohly b\u00fdt alespo\u0148 \u010d\u00e1ste\u010dn\u011b dopraveny na Zemi bombardov\u00e1n\u00edm asteroidy na po\u010d\u00e1tku historie Zem\u011b. Ve skute\u010dnosti byly podobn\u00e9 n\u00e1lezy hl\u00e1\u0161eny ji\u017e d\u0159\u00edve. Loni v\u011bdci p\u0159i anal\u00fdze t\u0159\u00ed meteorit\u016f, kter\u00e9 p\u0159ed lety dopadly na Zemi, na\u0161li dus\u00edkat\u00e9 b\u00e1ze nukleotid\u016f, ze kter\u00fdch se vytvo\u0159ila DNA a RNA (v\u00edce v textu: Kl\u00ed\u010dov\u00e9 prvky \u017eivota na Zemi nalezen\u00e9 v meteoritech). Nyn\u00ed <a href=\"https:\/\/www.novinkycz.cz\/\">podrobn\u00e1 anal\u00fdza<\/a> uk\u00e1zala, \u017ee na asteroidu Ryugu je p\u0159\u00edtomen uracil, jedna z pyrimidinov\u00fdch dus\u00edkat\u00fdch b\u00e1z\u00ed, kter\u00e9 tvo\u0159\u00ed RNA, molekulu, kter\u00e1 obsahuje instrukce pro stavbu a \u010dinnost \u017eiv\u00fdch organism\u016f. Ve vzorc\u00edch byl nalezen tak\u00e9 niacin, zn\u00e1m\u00fd tak\u00e9 jako kyselina nikotinov\u00e1 nebo vitam\u00edn B3, kter\u00fd hraje d\u016fle\u017eitou roli v metabolismu \u017eiv\u00fdch tvor\u016f.<\/p>\n\n\n\n<p><strong>Uracil a vitam<\/strong><strong>\u00edn B3 na Ryugu<\/strong><\/p>\n\n\n\n<p>Za zji\u0161t\u011bn\u00edmi stoj\u00ed mezin\u00e1rodn\u00ed t\u00fdm v\u011bdc\u016f pod veden\u00edm profesora Yasuhiro Oba z Hokkaidsk\u00e9 univerzity. <a href=\"https:\/\/www.presspress.cz\/\">V\u00fdsledky<\/a> anal\u00fdz nazna\u010duj\u00ed, \u017ee stavebn\u00ed kameny \u017eivota, alespo\u0148 tak, jak jej zn\u00e1me, se mohou tvo\u0159it ve vesm\u00edru a dostat se na Zemi pomoc\u00ed vesm\u00edrn\u00fdch kamen\u016f.<\/p>\n\n\n\n<p>&#8222;V\u011bdci ji\u017e d\u0159\u00edve na\u0161li nukleob\u00e1ze a vitam\u00edny v n\u011bkter\u00fdch meteoritech bohat\u00fdch na uhl\u00edk, ale v\u017edy tu byl probl\u00e9m kontaminace vystaven\u00edm zemsk\u00e9mu prost\u0159ed\u00ed,&#8220; vysv\u011btlil Oba. &#8222;Proto\u017ee Hayabusa2 odebrala dva vzorky p\u0159\u00edmo z asteroidu Ryugu a dopravila je na Zemi v uzav\u0159en\u00fdch kapsl\u00edch, lze kontaminaci vylou\u010dit,&#8220; dodal.<\/p>\n\n\n\n<p>V\u011bdci extrahovali tyto molekuly pono\u0159en\u00edm vzork\u016f z Ryugu do hork\u00e9 vody. Pot\u00e9 pou\u017eili techniky kapalinov\u00e9 chromatografie kombinovan\u00e9 s hmotnostn\u00ed spektrometri\u00ed s vysok\u00fdm rozli\u0161en\u00edm. To odhalilo p\u0159\u00edtomnost uracilu a kyseliny nikotinov\u00e9, stejn\u011b jako dal\u0161\u00edch organick\u00fdch slou\u010denin obsahuj\u00edc\u00edch dus\u00edk.<\/p>\n","protected":false},"excerpt":{"rendered":"<p>Anal\u00fdza vzork\u016f odebran\u00fdch z asteroidu Ryugu sondou Hayabusa2 uk\u00e1zala p\u0159\u00edtomnost uracilu, kter\u00fd je sou\u010d\u00e1st\u00ed nukleotid\u016f RNA. Ve vzorc\u00edch byly nalezeny i molekuly vitaminu B3. Tato zji\u0161t\u011bn\u00ed poskytuj\u00ed dal\u0161\u00ed d\u016fkaz, \u017ee d\u016fle\u017eit\u00e9 stavebn\u00ed kameny \u017eivota mohly b\u00fdt na Zemi doru\u010deny meteority. Ran\u00e1 Zem\u011b byla velmi nep\u0159\u00e1telsk\u00e9 m\u00edsto, n\u011bkdy dost hork\u00e9, aby roztrhalo molekuly nezbytn\u00e9 pro \u017eivot. [&hellip;]<\/p>\n","protected":false},"author":1,"featured_media":505,"comment_status":"open","ping_status":"open","sticky":false,"template":"","format":"standard","meta":{"tdm_status":"","tdm_grid_status":"","footnotes":""},"categories":[8],"tags":[],"class_list":{"0":"post-504","1":"post","2":"type-post","3":"status-publish","4":"format-standard","5":"has-post-thumbnail","7":"category-clanky-nasich-klientu"},"aioseo_notices":[],"amp_enabled":true,"_links":{"self":[{"href":"https:\/\/clankomat.cz\/index.php?rest_route=\/wp\/v2\/posts\/504","targetHints":{"allow":["GET"]}}],"collection":[{"href":"https:\/\/clankomat.cz\/index.php?rest_route=\/wp\/v2\/posts"}],"about":[{"href":"https:\/\/clankomat.cz\/index.php?rest_route=\/wp\/v2\/types\/post"}],"author":[{"embeddable":true,"href":"https:\/\/clankomat.cz\/index.php?rest_route=\/wp\/v2\/users\/1"}],"replies":[{"embeddable":true,"href":"https:\/\/clankomat.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcomments&post=504"}],"version-history":[{"count":1,"href":"https:\/\/clankomat.cz\/index.php?rest_route=\/wp\/v2\/posts\/504\/revisions"}],"predecessor-version":[{"id":506,"href":"https:\/\/clankomat.cz\/index.php?rest_route=\/wp\/v2\/posts\/504\/revisions\/506"}],"wp:featuredmedia":[{"embeddable":true,"href":"https:\/\/clankomat.cz\/index.php?rest_route=\/wp\/v2\/media\/505"}],"wp:attachment":[{"href":"https:\/\/clankomat.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fmedia&parent=504"}],"wp:term":[{"taxonomy":"category","embeddable":true,"href":"https:\/\/clankomat.cz\/index.php?rest_route=%2Fwp%2Fv2%2Fcategories&post=504"},{"taxonomy":"post_tag","embeddable":true,"href":"https:\/\/clankomat.cz\/index.php?rest_route=%2Fwp%2Fv2%2Ftags&post=504"}],"curies":[{"name":"wp","href":"https:\/\/api.w.org\/{rel}","templated":true}]}}