Nucleotide - menene wannan? A abun da ke ciki, tsari da lambar kuma jerin nucleotides a sarkar DNA

All rayuwa a duniya da aka hada da yawa Kwayoyin cewa goyi bayan ordering na kungiyar a kudi dauke a cikin nucleus din bayanan jinsi. Shi ne har yanzu ba, a aiwatar da daukar kwayar cutar hadaddun macromolecular mahadi - nucleic acid kunsha na monomer raka'a - nucleotides. ba shi yiwuwa a overestimate rawar da nucleic acid. Stability na wa gininsu ƙaddara da al'ada aiki da kwayoyin, da kuma wani sabawa a cikin tsarin zai babu makawa kai ga canje-canje a salon salula kungiyar, aiki na physiological matakai da viability na Kwayoyin a general.

A ra'ayi na mai nucleotide kuma da kaddarorin

Kowane kwayoyin na DNA ko RNA aka yi sama da karami monomeric mahadi - nucleotide. A wasu kalmomin, da nucleotides - Tubalan Ginin nucleic acid, co-enzymes da kuma wasu masu nazarin halittu mahadi, wanda suke da muhimmanci ga cell a lokacin da rai.

Babban Properties na wadannan muhimman abubuwa sun hada da:

• ajiya na bayanai game da furotin da tsarin da kuma gaji dabiu.
• Control a kan girma da kuma haifuwa.
• shiga a cikin metabolism da kuma wasu physiological matakai a cikin cell.

A abun da ke ciki na nucleotides

Da yake jawabi na nucleotides, ba za mu iya zauna a kan irin wannan muhimmanci batun yadda sifa da abun da ke ciki.

Kowane nucleotide kunshi:

• sugar saura.
• nitrogenous tushe.
• phosphate kungiyar ko wani saura na phosphoric acid.

Za mu iya cewa da nucleotide - wani hadadden kwayoyin fili. Dangane da takamaiman abun da ke ciki da kuma irin nitrogenous sansanonin a nucleotide pentose nucleic acid tsarin subdivided cikin:

• deoxyribonucleic acid ko DNA.
• ribonucleic acid, ko RNA.

Abun da ke ciki nucleic acid

A nucleic acid-pentose sugar da aka gabatar. Wannan biyar-carbon sukari a cikin DNA shi ne ake kira deoxyribose, a RNA - ribose. Kowane kwayoyin yana pentoses biyar carbon atoms, hudu daga wanda tare da oxygen zarra samar da wata biyar-membered zobe, da humushin da HO-CH2 kungiyar.

A matsayi na kowane carbon zarra a cikin kwayoyin pentose denoted Larabci adadi tare da wani Firayim (1C ', 2C ", 3C', 4C ', 5C'). Tun da dukan matakai karanta kayyade bayanai da nucleic acid kwayoyin da m directivity, da lambobin na carbon kwayoyin zarra da su tsari a cikin zobe bauta a matsayin akan hanyar da ta dace.

A hydroxyl kungiyar zuwa na uku da na biyar carbon atoms (da 3S '5s') a haɗe phosphoric acid saura. Ya kayyade sinadaran ainihi na DNA da RNA don wani rukuni na acid.

A farko carbon zarra (1s ') nitrogenous tushe a haɗe zuwa sugar kwayoyin.

Species abun da ke ciki nitrogenous sansanonin

Nucleotides na DNA nitrogenous sansanonin an wakilta hudu jinsunan:

• adenine (A);
• Bibyun (G).
• saitosin (C).
• taimain (T).

Biyu na farko ya kasance a cikin aji na purines, biyu na karshe - pyrimidine. Kwayoyin nauyi purine pyrimidine ne ko da yaushe mutum.

Nucleotides RNA nitrogenous sansanonin wakilta:

• adenine (A);
• Bibyun (G).
• saitosin (C).
• uracil (U).

Uracil kazalika da taimain, a pyrimidine tushe.

A cikin kimiyya wallafe-wallafe da kuma iya sau da yawa sami wasu nadi nitrogenous sansanonin - Latin haruffa (A, T, C, G, U).

Greater daki-daki, da sinadaran tsarin na purines da pyrimidines.

Pyrimidines, wato, saitosin, taimain da uracil, a cikin tsarin wakilta biyu nitrogen kwayoyin zarra da hudu carbon atoms kafa shida membered zobe. Kowane zarra na da lamba daga 1 zuwa 6.

Purines (adenine da kuma Bibyun) kunshi pyrimidine da imidazole ko biyu heterocycles. Kwayar Komayya purine sansanonin wakilta hudu nitrogen kwayoyin zarra da biyar carbon atoms. Kowane zarra ƙidaya daga 1 zuwa 9.

A sakamakon fili na nitrogenous tushe da kuma wani pentose saura kafa nucleoside. Nucleotide - a nucleoside fili da kuma a phosphate kungiyar.

Da samuwar phosphodiester shaidu

Yana da muhimmanci a gane tambaya na yadda za a hada da nucleotides a sarkar polypeptide samar da wata nucleic acid kwayoyin. Wannan ya faru saboda da ake kira phosphodiester shaidu.

Hulda da biyu nucleotides ba dinucleotide. Samuwar sabuwar mahadi faruwa da sandaro kamar tsakanin phosphate saura na daya monomer da wani hydroxy pentose phosphodiester bond faruwa.

Polynucleotide kira - maimaita maimaitawa na wannan dauki ( 'yan sau miliyan). A polynucleotide sarkar da aka gina ta kafa phosphodiester shaidu tsakanin uku da biyar carbons sugars (3S 'kuma 5s').

Taruwa, polynucleotide - wani hadadden tsari da yake faruwa a lokacin da enzyme DNA polymerase, wanda ya samar da kawai da sarkar girma a daya karshen (3 ') tare da free hydroxy kungiyar.

A tsarin da jigidar halittar DNA

A jigidar halittar DNA, kazalika da gina jiki na iya zama wani primary, secondary da kuma manyan tsarin.

A jerin nucleotides a sarkar DNA ma'anar ta farko tsarin. Secondary tsarin da aka kafa saboda hydrogen shaidu, tushen abin da ya faru aza complementarity manufa. A wasu kalmomin, a cikin kira na DNA biyu Helix abubuwa wasu tsari: adenine, taimain yayi dace da mai kula da da'ira sauran, Bibyun - saitosin, kuma mataimakin versa. Nau'i-nau'i daga adenine da kuma taimain ko Bibyun da saitosin an kafa ta biyu a cikin ta farko, kuma a karshen harka uku hydrogen shaidu. Irin wannan fili na samar da wani m bond nucleotide, sarƙoƙi da daidaita nesa tsakanin su.

Sanin jerin nucleotides a sarkar DNA ta hanyar da manufa na complementarity za a iya kara biyu ko kari.

A manyan tsarin da DNA hadaddun da aka kafa ta uku-girma shaidu, wanda kwayoyin sa shi mafi m da m sanya a cikin wani karamin girma cell. Alal misali, E. coli DNA tsawon shi ne mafi girma daga 1 mm, yayin da cell tsawon - na kasa da 5 microns.

Yawan nucleotides a cikin DNA, da kuma shi ne su gwada yawa dangantaka shi ne batun mulkin Chergaffa (yawan purine sansanonin ne ko da yaushe daidaita da adadin pyrimidine). A nisa tsakanin nucleotides - akai daidai 0,34 nm, kuma su kwayoyin nauyi.

A tsarin da wani halitta ta RNA

RNA da aka wakilta guda polynucleotide sarkar, kafa ta covalent shaidu tsakanin pentose (ribose a cikin wannan hali) da kuma wani phosphate moiety. A tsawon shi ne ya fi guntu DNA. A jinsin abun da ke ciki na nitrogenous sansanonin a nucleotide kuma akwai bambance-bambance. The RNA pyrimidine tushe taimain maimakon uracil amfani. Dangane da ayyuka yi a cikin jiki, RNA iya zama na uku iri.

• ribosomal (rRNA) - za kullum dauke daga 3,000 zuwa 5,000 nucleotides. Kamar yadda wani zama dole tsarin bangaren da aka hannu a cikin samuwar aiki cibiyar na ribosomes, da wurare na daya daga cikin mafi muhimmanci matakai a cikin cell - gina jiki biosynthesis.
• sufuri (tRNA) - kunshi wani talakawan of 75 - 95 nucleotides, ya yi aikin canja wuri zuwa wuri da ake so amino acid polypeptide kira a ribosome. Kowane irin tRNA (a kalla 40) yana da nasa muhimmi ne kawai don shi a jerin nucleotides ko monomers.
• Bayani (RNAi) - a nucleotide abun da ke ciki ne sosai bambancin. Transfer kayyade bayanai daga DNA to ribosomes, abubuwa a matsayin wani samfuri ga kira na sunadari.

Rawar da nucleotides a cikin jiki

Nucleotides a cikin cell yi da dama da muhimmanci ayyuka:

• Ana amfani da gini tubalan ga nucleic acid (nucleotide purine da pyrimidine jerin).
• suna da hannu a cikin da yawa tafiyar matakai na rayuwa a cikin cell.
• ɓangare na ATP - babban makamashi Madogararsa a Kwayoyin.
• yi kamar yadda vectors na rage equivalents a cikin cell (nad +, NADP +, fad, FMN).
• yi kamar yadda bioregulators.
• za a iya gani a matsayin na biyu da manzanni extracellular yau da kullum da kira (msl, Camp ko cGMP).

Nucleotide - a monomer naúrar cewa suranta mafi hadaddun mahadi - nucleic acid, ba tare da wanda da canja wurin da kwayoyin bayanai, ta ajiya da kuma sake kunnawa. Free nucleotides ne babban aka gyara da hannu a cikin siginar makamashi tafiyar matakai da kuma goyon bayan Kwayoyin da al'ada aiki na dukan kwayoyin.