Qhov Tseem Ceeb Qhov txawv - Topoisomerase I vs II
DNA xav tau los ntawm ib lub xovtooj thiaj li yuav faib ua ob tug ntxhais los ntawm kev faib cell. DNA yog duplicated los ntawm DNA replication. Yog li, yuav tsum muaj ib lub tswv yim tshwj xeeb txhawm rau txhawm rau rov ua dua qhov mob siab heev spiraled DNA. Topoisomerase yog ib qho enzyme uas tuaj yeem txiav DNA ntawm ib qho chaw tshwj xeeb thiab tshem tawm DNA twist thiab txo cov DNA supercoil xwm. Nws yog cov enzyme uas koom nrog hauv winding thiab unwinding DNA. Qhov teeb meem winding ntawm DNA yog tsa los ntawm kev sib txuas ntawm cov qauv ntawm ob-stranded DNA. Cov hom teeb meem saum toj no tsim nyob rau hauv DNA doubled strands tuaj yeem kho los ntawm topoisomerases. Lawv feem ntau txiav cov DNA phosphate qaum ib leeg los yog ob qho tib si thiab tso cai rau DNA supercoil qauv kom tsis muaj mob. Tom qab DNA caj qaum rov qab rov qab dua. Cov kab mob thiab tib neeg topoisomerases muaj cov txheej txheem zoo sib xws. Topoisomerase I thiab II yog cov txheej txheem ntawm kev soj ntsuam nrog supercoiled DNA. Topoisomerase Kuv txiav ib txoj hlua hauv ob txoj hlua DNA thiab tsis muaj ATP yuav tsum tau ua rau nws txoj haujlwm. Ntawm qhov tod tes, Topoisomerase, II txiav ob qho tib si hauv DNA thiab xav tau ATP rau nws cov haujlwm. Qhov no yog qhov txawv ntawm Topoisomerase I thiab II.
Topoisomerase kuv yog dab tsi?
Topoisomerase Kuv yog ib chav kawm ntawm enzyme uas koom nrog kev tswj hwm ntawm DNA supercoiling. Lawv tswj cov supercoiling hauv DNA los ntawm kev tsim ib leeg-stranded so thiab relegating DNA strands. Lawv lub luag haujlwm tseem ceeb heev rau DNA replication thiab transcription. Lawv tau muab faib ua hom IA thiab hom IB. Hom IA topoisomerases yog hu ua prokaryotic topoisomerases I. Ntawm qhov tod tes, hom IB topoisomerases raug xa mus rau eukaryotic topoisomerases I. Hom IA thiab hom IB topoisomerases yog qhov sib txawv. Lub prokaryotic topoisomerase Kuv tsuas tuaj yeem rov ua qhov tsis zoo DNA supercoils. Thiab eukaryotic topoisomerase Kuv tuaj yeem qhia qhov zoo DNA supercoils, thiab lawv cais cov DNA ntawm tus ntxhais chromosome tom qab rov ua dua, thiab so cov DNA no.
Daim duab 01: Topoisomerase I thiab II
Lub Ecoli topoisomerase kuv yog ib qho holoenzyme nrog peb Zn (II) atoms nyob rau hauv tetracysteine motifs ze nws carboxy terminus. Nws yog 97 kDa hauv qhov hnyav. Topoisomerase Kuv muaj ob peb yam txawv txawv. Nws tsis xav tau ATP hydrolyzing los catalyze lub topological rearrangement ntawm DNA. Qhov kev tawm ntawm lub topoisomerase kuv yog, nws yog ib tug tag nrho functional monomer thaum feem ntau enzymes uas koom nrog cov complex DNA topological rearrangements yog oligomeric nyob rau hauv cov xwm.
Topoisomerase II yog dab tsi?
txhawm rau tswj cov DNA tangles thiab supercoils, hom II topoisomerase txiav ob lub DNA strands ib txhij. Lawv xav tau ATP hydrolyzing rau qhov haujlwm no. Hom II topoisomerase hloov pauv tus lej txuas ntawm lub voj voog DNA los ntawm ± 2. Lawv tau muab faib ua ob pawg xws li, Hom II A thiab Hom IIB.
Daim duab 02: Topoisomerase II
Types II A topoisomerases suav nrog cov kab mob DNA gyrase, eukaryotic topoisomerase II, eukaryal viral topoisomerase alpha & beta thiab topoisomerase IV. Hom II B topoisomerases muaj xws li topoisomerase VI pom nyob rau hauv archaea thiab topoisomerase VI pom nyob rau hauv cov nroj tsuag siab dua. Lub luag haujlwm ntawm topoisomerase II yog txiav ob qho tib si ntawm ib DNA ob lub helix thiab dhau mus rau lwm qhov tsis sib xws DNA helix los ntawm nws. Thaum kawg, txiav xaus yog relegated dua. Inhibitor molecules rau topoisomerase II tuaj yeem pom xws li Hu-331, ICRF-193, thiab mitindomide.
Dab tsi yog qhov zoo sib xws ntawm Topoisomerase I thiab II?
- Ob leeg yog cov enzymes koom nrog hauv kev txo cov supercoils.
- Ob leeg pom muaj nyob hauv cov kab mob prokaryotic thiab hauv cov kab mob eukaryotic.
- Ob qho tib si topoisomerase I thiab II lub luag haujlwm tseem ceeb heev txhawm rau txhawm rau tswj hwm DNA kom zoo thiab hloov pauv hauv cov cell nyob.
- Ob leeg yog cov protein hauv cov xwm txheej.
Qhov txawv ntawm Topoisomerase I thiab II yog dab tsi?
Topoisomerase I vs Topoisomerase II |
|
| Type I topoisomerase yog ib qho enzyme uas hloov cov qib ntawm supercoiling ntawm DNA los ntawm kev ua rau ib leeg-strand so thiab tshem tawm. | Type II topoisomerase yog ib qho enzyme uas hloov cov qib ntawm supercoiling ntawm DNA los ntawm kev ua rau ob lub strands tawg thiab tshem tawm. |
| ATP Hydrolyzing | |
| Topoisomerase Kuv tsis xav tau ATP hydrolyzing rau nws txoj haujlwm. | Topoisomerase II yuav tsum xav tau ATP hydrolyzing rau nws txoj haujlwm. |
| DNA tawg | |
| Topoisomerase Kuv ua ib txoj hlua tawg. | Topoisomerase II ua ob txoj hlua tawg. |
| qauv | |
| Topoisomerase Kuv yog monomer. | Topoisomerase II yog heterodimer. |
| Hloov tus lej txuas ntawm lub voj voog DNA | |
| Topoisomerase Kuv hloov pauv tus lej txuas ntawm cov DNA ncig los ntawm cov units nruj me ntsis 1 lossis ntau ntawm 1(n). | Topoisomerase II hloov pauv tus lej txuas ntawm DNA ncig los ntawm cov units ntawm ± 2. |
Summary – Topoisomerase I vs II
Cov topoisomerases yog cov enzymes uas koom nrog hauv winding lossis unwinding ntawm DNA. Lawv txo cov DNA supercoils thiab pab txhawb DNA replication thiab transcription. Cov enzymes no tuaj yeem pom hauv yuav luag txhua yam kabmob xws li; tib neeg, kab mob, cov nroj tsuag siab dua, lwm yam kab mob, thiab archaea. Topological DNA rearrangements yog ua los ntawm topoisomerases. Lub ATP hydrolyzing tsis xav tau rau kev ua haujlwm ntawm topoisomerase I. Topoisomerase Kuv txiav ib txoj hlua hauv DNA. Ntawm qhov tod tes, topoisomerase II txiav ob qho tib si hauv DNA thiab xav tau ATP rau lawv txoj haujlwm lossis kev ua haujlwm. Tom qab ntawd cov kev txiav hauv DNA caj qaum tau rov ua dua. Cov kab mob thiab tib neeg topoisomerases muaj cov txheej txheem zoo sib xws. Qhov no yog qhov txawv ntawm Topoisomerase I thiab II.
Download the PDF Version of Topoisomerase I vs II
Koj tuaj yeem rub tawm PDF version ntawm kab lus no thiab siv nws rau offline lub hom phiaj raws li daim ntawv ceeb toom. Thov download PDF version ntawm no Qhov txawv Ntawm Topoisomerase I thiab II
