Nucleotide - ihe bụ nke a? The mejupụtara, Ọdịdị, ọnụ ọgụgụ na usoro nke nucleotides na DNA yinye

All ndụ na mbara ala na-emi esịnede ọtụtụ mkpụrụ ndụ na-akwado ndị ịtụ nke nzukọ ha na-efu dị na ntọala nke mkpụrụ ndụ ihe nketa na ozi. Ọ bụ ka ugbu a, na-emejuputa atumatu na-ebute site ná mgbagwoju macromolecular ogige - a nucleic acid esịnede nke monomer nkeji - nucleotides. ọ gaghị ekwe omume overestimate ọrụ nke nucleic asịd. Kwụsie ike nke ha owuwu kpebisiri ike site kwesịrị ịrụ ọrụ nke organism, na ihe ọ bụla deviations na Ọdịdị ga-apụghị izere ezere na-eduga mgbanwe cellular nzukọ, ọrụ nke n'ahụ Filiks ma na ọganihu nke mkpụrụ ndụ n'ozuzu.

Echiche nke a nucleotide na ya Njirimara

Onye ọ bụla molekul nke DNA ma ọ bụ RNA mee nke nta monomeric ogige - nucleotide. Na ndị ọzọ okwu, nucleotides - ụlọ nkanka nke nucleic asịd, ngalaba-enzymes na ọtụtụ ndị ọzọ ndu ogige, nke bụ oké egwu cell n'oge ya ndụ.

Isi Njirimara ndị a dị oké mkpa bekee na-agụnye:

• nchekwa nke ihe ọmụma banyere ndị protein Ọdịdị na ketara àgwà;
• Control n'elu uto na amụba;
• isonye na metabolism na ọtụtụ ndị ọzọ n'ahụ Filiks ke cell.

The mejupụtara nke nucleotides

Ekwu okwu nke nucleotides, anyị nwere ike adịghị eche otú ahụ dị mkpa nke dị ka ha mebere atumatu ma mejupụtara.

Onye ọ bụla nucleotide mejupụtara:

• sugar fọduru;
• nitrogenous isi;
• phosphate otu ma ọ bụ a fọduru nke phosphoric acid.

Anyị nwere ike ikwu na nucleotide - a mgbagwoju organic compound. Dabere na kpọmkwem mejupụtara na ụdị nitrogenous bases na nucleotide pentose nucleic acid Ọdịdị subdivided n'ime:

• deoxyribonucleic acid ma ọ bụ DNA;
• ribonucleic acid, ma ọ bụ RNA.

Mejupụtara nucleic acid

The nucleic acid-pentose sugar na-dị. -Ise a carbon sugar na DNA na-akpọ deoxyribose, na RNA - ribose. Onye ọ bụla molekul nwere pentoses ise carbon atọm, anọ nke ọnụ na oxygen atọm etolite a ise-membered mgbanaka, na-ise nke HO-CH2 otu.

Ọnọdụ nke onye ọ bụla carbon atọm na molekul pentose denoted Arabic onuogugu na a praịm (1ch ', 2C', 3C ', 4C', 5C '). Ebe niile Filiks na-agụ nke mkpụrụ ndụ ihe nketa ọmụma na nucleic acid ụmụ irighiri nwere a siri ike directivity, nọmba na carbon atọm na ha ndokwa mgbanaka na-eje ozi dị ka a pointer ziri ezi na direction.

The hydroxyl ìgwè nke atọ na-ise carbon atọm (na 3S '5S') mmasị phosphoric acid fọduru. Ọ na-ekpebi ndị chemical njirimara nke DNA na RNA otu ìgwè nke asịd.

The mbụ carbon atọm (1S ') nitrogenous isi mmasị ka sugar molekul.

Umu anumanu na osisi mejupụtara nitrogenous bases

Nucleotides nke DNA nitrogenous bases na-anọchi anya ya anọ umu:

• ebe adenin (A);
• Gwanine (G);
• agakọta (C);
• agakọtakwa (T).

The mbụ na nke abụọ bụ ndị nke klas nke purines, abụọ ikpeazụ - pyrimidine. Molekụla ibu purine pyrimidine bụ mgbe arọ.

Nucleotides RNA nitrogenous bases bịa:

• ebe adenin (A);
• Gwanine (G);
• agakọta (C);
• uracil (U).

Uracil nakwa dị ka agakọtakwa, a pyrimidine isi.

Na nkà mmụta sayensị ndị e ji amụ na ike na-achọpụta mgbe mgbe ọzọ designation nitrogenous bases - Latin mkpụrụedemede (A, T, C, G, U).

Greater zuru ezu na chemical Ọdịdị nke purines na pyrimidines.

Pyrimidines, ya bụ, sitosin, agakọtakwa na uracil, na Ọdịdị ahụ nọchiri anya ya abụọ nitrogen atọm na anọ carbon atọm akpụ a isii membered mgbanaka. Kwa atọm nwere ya nọmba site 1 6.

Purines (ebe adenin na Gwanine) mejupụtara pyrimidine na imidazole ma ọ bụ abụọ heterocycles. Molekul purine bases anọchi anya anọ nitrogen atọm na ise carbon atọm. Onye ọ bụla atọm agukọta site 1 9.

Ihe compound nke nitrogenous isi na a pentose fọduru kpụrụ abụọ n'ime. Nucleotide - a abụọ n'ime compound na a phosphate otu.

The guzobere phosphodiester nkekọ

Ọ dị mkpa ịghọta ajụjụ nke otú ikpokọta nucleotides na polypeptide yinye na-etolite a nucleic acid molekul. Nke a na-eme n'ihi na a na-akpọ phosphodiester agbụ.

Mmekọrịta nke abụọ nucleotides enye dinucleotide. Formation nke ọhụrụ ogige emee site odide dị ka n'etiti phosphate fọduru nke otu monomer na ọzọ hydroxy pentose phosphodiester nkekọ emee.

Polynucleotide njikọ - ugboro ugboro ugboro ugboro a mmeghachi omume (a ole na ole nde ugboro). A polynucleotide yinye na-wuru ya akpụ phosphodiester nkekọ dị n'etiti nke atọ na ise carbons shuga n'ókè (3S 'na 5S').

Ịgbakọta polynucleotide - a mgbagwoju usoro na-ewe ebe mgbe enzyme DNA polymerase, nke na-enye naanị yinye ibu na otu njedebe (3 ') na a free hydroxy otu.

Ọdịdị nke ahụ DNA molekul

A DNA molekul nakwa dị ka protein nwere ike ịbụ a bụ isi, sekọndrị na tertiary Ọdịdị.

The usoro nke nucleotides na DNA yinye akowa ya isi Ọdịdị. Secondary Ọdịdị a kpụrụ n'ihi hydrogen agbụ, ndabere nke nke omume tọrọ complementarity edumbet. Ndị ọzọ okwu, na njikọ nke DNA abụọ helix eme ụfọdụ mgbe nile: ebe adenin, agakọtakwa kwekọrọ na a circuit ọzọ, Gwanine - agakọta na Anglịkan. Ụzọ abụọ nke ebe adenin na tamin ma ọ bụ Gwanine na sitosin ii site abụọ na ndị mbụ na na ikpeazụ ikpe atọ hydrogen agbụ. Ndị dị otú ahụ a compound na-enye a siri ike nkekọ nucleotide ígwè ma hà anya n'etiti ha.

Ịmara na nsoro nke nucleotides na a DNA yinye site ụkpụrụ nke complementarity nwere ike ịgbatị abụọ ma ọ bụ emeju.

The tertiary Ọdịdị nke ahụ DNA mgbagwoju a kpụrụ site atọ akụkụ agbụ, nke molekul na-eme ya ndị ọzọ kọmpat na ike enịm ke a obere olu cell. Ka ihe atụ, E. coli DNA ogologo bụ ukwuu karịa 1 mm, mgbe ahụ cell ogologo - nke na-erughị 5 microns.

The ọnụ ọgụgụ nke nucleotides na DNA, na ọ bụ ha quantitative mmekọrịta bụ isiokwu na-achị Chergaffa (nọmba nke purine bases bụ mgbe niile hà ego nke pyrimidine). The anya n'etiti nucleotides - a mgbe nile na-hà 0,34 nm, na ha molekụla arọ.

Ọdịdị nke ihe RNA molekul

RNA na-anọchi anya otu polynucleotide yinye, kpụrụ covalent nkekọ dị n'etiti pentose (ribose na nke a) na a phosphate moiety. Na ogologo ọ bụ ọtụtụ ihe mkpumkpu DNA. The umu mejupụtara nke nitrogenous bases na nucleotide na e nwere ndị dị iche iche. The RNA pyrimidine isi agakọtakwa kama uracil eji. Dabere na ọrụ rụrụ ke idem, RNA nwere ike nke atọ ụdị.

• Ribosomal (rRNA) - ga-n'ozuzu nwere site 3,000 na 5,000 nucleotides. Dị ka a dị mkpa bughi akụrụngwa a na-guzobere n'ọrụ center nke ribosomes, ebe otu n'ime ihe ndị kasị mkpa Filiks ke cell - protein biosynthesis.
• Transport (tRNA) - mejupụtara nkezi nke 75 - 95 nucleotides, anamde nyefe ebe chọrọ amino acid polypeptide nsụchi ribosome. Onye ọ bụla ụdị tRNA (dịkarịa ala 40) nwere ya pụta ụwa naanị ya a usoro nke nucleotides ma ọ bụ monomers.
• Ozi (RNAi) - na nucleotide mejupụtara bụ nnọọ iche iche. Nyefee nke mkpụrụ ndụ ihe nketa na ozi sitere na DNA na ribosomes,-eme dị ka a na atụrụ nke njikọ nke protein molekul.

The ọrụ nke nucleotides ke idem

Nucleotides na cell ịrụ a ọnụ ọgụgụ nke dị mkpa na ọrụ:

• na-eji dị ka ụlọ nkanka maka nucleic asịd (nucleotide purine na pyrimidine usoro);
• na-abuana ke ọtụtụ metabolic Filiks ke cell;
• akụkụ nke ATP - isi ike iyi na mkpụrụ ndụ;
• eme omume dị ka Vektọ nke mbenata kachasị yitebe na cell (nad +, NADP +, fad, FMN);
• eme omume dị ka bioregulators;
• nwere ike ga-atụle ka nke abụọ ozi extracellular mgbe njikọ (e.g., mara ụlọikwuu ma ọ bụ cGMP).

Nucleotide - a monomer unit na Nleta ihe mgbagwoju ogige - nucleic asịd, enweghị nke nyefe nke mkpụrụ ndụ ihe nketa na ozi, ya nchekwa na playback. Free nucleotides bụ isi mmiri abuana ke mgbaàmà ike Filiks ma na-akwado mkpụrụ ndụ na kwesịrị ịrụ ọrụ dum organism.