The degeneracy ea khoutu liphatsa tsa lefutso: le lintho tsa motheo

The khoutu liphatsa tsa lefutso e hlalosoa e le codons, tsamaiso ya khouto boitsebiso bo mabapi le sebōpeho sa lihaha-'mele, tlholeho ka phelang tsohle tse phelang lefatšeng. Tshirololo nka lilemo tse mashome, empa ha e le hantle hore o teng, saense e utloisisa hoo e ka bang lilemong tse lekholo tse. Versatility, khethehileng, unidirectional, 'me haholo-holo degeneracy ea khoutu liphatsa tsa lefutso ho ba le moelelo oa lintho tse phelang.

History of tse sibolotsoeng

The bothata ba ho khouto lesedi liphatsa tsa lefutso 'nile senotlolo thutong ea baeloji. Ke sebopeho popeho ya khoutu liphatsa tsa lefutso, saense tsoela pele ho ena butle. Ho tloha ka ho fumanoa ha J. Watson le Crick ka 1953. The habeli Helix sebōpeho sa DNA entered mohato ya ho rarolla e khoutu sebopeho ka boeona, eo susumelletsa ho lumela ka boholo ba lintho tsa tlhaho. Sebopeho guttate liprotheine le DNA ea sebopeho tšoanang fana ka maikutlo a ho ba teng ha khoutu liphatsa tsa lefutso, ba ka ngollano pakeng tsa litemana tsa tse peli, empa a tlalehiloeng ka alphabets fapaneng. 'Me haeba alfabeta ea liprotheine e se e tsebahala, le matshwao DNA e ne e le taba ea ho ithuta ea baeloji, fisiks le ea lipalo.

Ho na le ke ho hlokahale hore hlalosa mehato tsohle ka tharollo ea Enigma ena. Ka ho toba teko, e ile le tiisa hore pakeng tsa codons DNA le-amino acid tsa protheine e ho na le e hlakileng 'me ka tsela e lumellanang ka ho latellana ha tšoaroa ka 1964 Charles Janowski le S. Brenner. A ka ho eketsehileng - nakong ea decoding ya khoutu liphatsa tsa lefutso ka vitro (ka vitro) sebelisa mekhoa ea tswakana protheine ka dibopeho-cell mahala.

Botlalo decrypted khoutu E. coli ile phatlaladitsweng ka 1966, litsebi tsa baeloji li ka neheletsano ka Cold Spring Harbor (USA). Ka mor'a moo ke o ile a bula redundancy (degeneracy) ya khoutu liphatsa tsa lefutso. Seo hona ho bolela hore, ho hlalosa haholo feela ho.

decoding tsoela pele

Ho deciphering ya data lefa khoutu fetohile e mong oa liketsahalo tsa bohlokoa ka ho fetisisa tsa lekholong la lilemo la ho qetela. Kajeno, saense e tsoela pele ho hlahloba ka botebo ka mekgwa ea tsamaiso ea limolek'hule khouto le litšobotsi tsa lona le e overabundance tsa matšoao, seo se bolela hore ka thepa ea degeneracy ea khoutu liphatsa tsa lefutso. Phuputso e entsoeng ka thoko ea indasteri ea - ka tšimoloho le ho iphetola ha lintho ea lefa oona tsamaisong tse bonahalang tsoaneng e. Bopaki bo tsoang polynucleotides (DNA) le polypeptides (liprotheine) o ile a fa peleka ho ntshetsopele ya baeloji ea limolek'hule. Le hore, le eena, theknoloji ea baeloji, bioengineering, tse sibolotsoeng ka ho ikatisa le semela hōla.

Dogmas le melawana

Home thuto ea baeloji ea limolek'hule - lesedi e tlosoa DNA ho lenģosa RNA, ebe le eena ka protheine e. Ka lehlakoreng le fapaneng tsa phetiso ea ka etsahala ho tloha RNA ho DNA le RNA ka RNA tse ling.

Empa popeho kapa motheong oa DNA kamehla o hlola ka ho. 'Me e mong litšobotsi tsohle tsa motheo tsa phetiso lesedi - bontša ea mofuta wa phetiso ea lenaane-thalo le. E leng, ka ho etsa phetiso ho tswakana ea limolek'hule tse ling tse popeho, e leng tla ba le ho ikatisa ya sebopeho oa boitsebiso bo liphatseng tsa lefutso.

khoutu liphatsa tsa lefutso

Line Coding sebōpeho sa limolek'hule tsa protheine ka tlatsetsang codons (triplets) nucleotides, tseo feela 4 (adein, guanine, cytosine, thymine (uracil)), eo ka boithatelo e isa hore ho thehoe liketane tse ling tsa nucleotides. Palo e tšoanang ea nucleotides le lik'hemik'hale complementarity - sena ke boemo bo ka sehloohong bakeng sa tswakana joalo. Empa sebopeho sa protheine molek'hule boleng matching lenane le boleng ea monomers hase (DNA nucleotides - protheine amino acid). Ena ke tsela ea tlhaho lefa khoutu - tsamaiso e khopo ho rekota ka tatelano ea nucleotides (codons) le amino acid e tatelano ea protheine ena.

Liphatseng tsa lefutso khoutu na thepa 'maloa:

• Triplet.
• The ikhetha.
• Dikamano.
• Disjointness.
• Redundancy (degeneracy) ya khoutu liphatsa tsa lefutso.
• Versatility.

Mona ke tlhaloso e khutšoanyane, ho lebisa tlhokomelo bohlokoa tsa likokoana-hloko.

Triplet, tswelopela le ho fumaneha stoplights

E mong le e ba 61-amino acid ngollana ya labeled semantic sa t (triplet) nucleotides. Tharo triplets se etsa boitsebiso bo mabapi le asiti amino le ke setopong codons. E mong le e nucleotide ka ketane ke setho sa triplet, 'me ha a eo ka boeona. Qetellong le e le qalo ea letoto la nucleotides tsamaisanang le protheine e le 'ngoe, ke codons setopong. Ba qala kapa setopong kgaso (the tswakana tsa protheine molek'hule).

Khethehileng, 'me a le mong-pointedness disjointness

E mong le e codon (triplet) encodes le 'ngoe feela amino acid e. E mong le e triplet e ikemetseng ho tloha le ha lepelela haufi. nucleotide ho motho ea ka ho matleng a triplet le 'ngoe feela ka ketane ena. Protein tswakana eona, kamehla e tataiso le 'ngoe feela, hore e laoloa setopong codons.

The redundancy ya khoutu liphatsa tsa lefutso

E mong le e triplet tsa nucleotides encodes amino acid e le 'ngoe. Kakaretso ea nucleotides 64, 61 ba bona ba - khouthollotsweng amino acid e (kutloisiso e codon), 'me tse tharo - lefeela, ke hore, amino acid e ha e encode (emisa codons). The redundancy (degeneracy) ya khoutu liphatsa tsa lefutso e le hore substitutions ka etswa ka ho e mong le e triplet - khōlō (ea isang ho amino acid e Phetolo) le mekhoa e tloaetsoeng (-amino acid sa fetole sehlopha sa). Ho bonolo ho a bale hore haeba triplet e ka ho phethahatsoa 9 substitutions (1, 2 le ho 3 maemo a), e mong le e nucleotide ka nkeloa sebaka ke 4 - 1 = 3 le mothofatso le leng, palo ea khoneha substitutions nucleotide tla 61 ho 9 = 549.

The degeneracy ea khoutu liphatsa tsa lefutso ho bontšoa e le hantle hore dikgetho 549 - e le lintho tse ngata ho feta hlokahalang bakeng sa boitsebiso bo zakodirovki ka 21 amino acid. Tabeng ena ea dikgetho Phetolo 549 23 etella pele hore ho thehoe ka setopong codon, 134 + 230 tloswa - ke mekhoa e tloaetsoeng substitutions, le 162 - khōlō.

Busa degeneracy le ntle le mabaka a

Ha codons tse peli ba le tse peli tse tšoanang pele nucleotide, ho nucleotides setseng ba hlahisa le sehlopha (purine kapa pyrimidine), tlhahisoleseding ba etsa se tšoanang amino acid e. Sena ke hangata degeneracy kapa redundancy ya khoutu liphatsa tsa lefutso. ntle le mabaka a mabeli - AUA le UGA - pele encodes methionine, le hoja e ne e tla lokela ho isoleucine, 'me ea bobeli - ka setopong codon, empa o ne a tla lokela ho encode tryptophan.

E bolelang degeneracy le versatility

Tsena thepa e 'meli ea khoutu liphatsa tsa lefutso na le phahameng ka ho fetisisa boleng likokoana-hloko. thepa ea bohle ho tse thathamisitsoeng ka holimo ke bath ba boitsebiso bo liphatseng tsa lefutso tsa mefuta eohle ea lintho tse phelang polaneteng ea rōna.

The degeneracy ea khoutu liphatsa tsa lefutso e na le boleng etsehang, e le kopitsa khafetsa e le 'ngoe khoutu amino acid e. Ho phaella moo, hona ho bolela phokotso bohlokoa ka (degeneration) ya nucleotide boraro ka codon ka. Joalo mothofatso e kokitisa le diso mutational ka DNA, e leng akarelletsa ditlolo tebileng sebopeho le protheine. Ena ke mochine sireletsa lintho tse phelang lefatšeng.