Qhov sib txawv tseem ceeb ntawm BL21 thiab DH5 Alpha yog tias BL21 yog qhov tsis txaus ntawm kev tsim cov noob caj noob ces muaj peev xwm E. coli cell siv feem ntau rau kev qhia cov protein, thaum DH5 Alpha yog cov tshuaj genetic engineered muaj peev xwm E. coli cell nrog recA1 kev hloov pauv siv feem ntau. rau plasmid transformation.
E. coli yog ib qho ntawm cov kab mob nto moo ntawm kev xaiv rau recombinant protein ntau lawm. Nws tau dhau los ua qhov nrov tshaj plaws nthuav qhia platform ntau xyoo. Nws kuj yog siv los ua lub chaw tsim khoom ntawm tes. BL21 thiab DH5 Alpha yog ob lub noob caj noob ces tsim E. coli hlwb tam sim no siv rau kev qhia cov protein thiab plasmid transformation, feem.
BL21 yog dab tsi?
BL21 yog qhov tsis txaus ntawm cov tshuaj genetic engineered muaj peev xwm E.coli cell feem ntau siv rau kev qhia cov protein. E. coli BL21 yog ib hom kab mob uas kis tau los ntawm cov kab mob B. Nws muaj qhov tsis xws luag ntawm Lon protease thiab ompT txheej membrane protease. Nws yog feem ntau siv rau recombinant protein qhia vim hais tias nws ib txwm coj stability rau qhia cov proteins. BL21 muaj txiaj ntsig zoo rau kev qhia cov protein nrog pCold I-IV DNA thiab pCold TF DNA. Tab sis qhov muaj peev xwm E. coli cell no tsis yog tsim rau kev qhia cov protein uas siv T7 txhawb nqa xws li pET system. Yog vim li cas tom qab qhov no yog BL21 tsis qhia T7 RNA polymerase. Tsis tas li ntawd, nws tsis pom zoo siv rau kev tsim kho lossis kev npaj ntawm plasmid vim nws tsis muaj kev hloov pauv.
Daim duab 01: BL21
BL21 tau piav qhia thawj zaug los ntawm Studier hauv xyoo 1986 tom qab kev hloov kho ntau yam ntawm kab B. BL21 hlwb tsis muaj nyob rau hauv LON protease, uas degrades ntau txawv teb chaws proteins. Tsis tas li ntawd, nws tau ploj lawm lwm cov noob uas cov lej rau cov txheej txheem txheej txheej sab nrauv (OmpT) uas nws txoj haujlwm yog txhawm rau txo qis cov protein ntau hauv cov cellular. Qhov tsis muaj cov proteins no ua rau muaj kev vam meej ntawm cov protein txawv teb chaws hauv E. coli BL21 hlwb. Tsis tas li ntawd, hsdSB kev hloov pauv hauv cov hlwb no tiv thaiv DNA methylation txawv teb chaws thiab cuam tshuam hauv BL21 hlwb.
DH5 Alpha yog dab tsi?
DH5 Alpha yog ib qho kev tsim kho caj ces muaj peev xwm E. coli cell nrog recA1 kev hloov pauv uas feem ntau siv rau kev hloov pauv plasmid. DH5 Alpha E. coli hlwb yog tsim los ntawm genetic engineered los ntawm American biologist Douglas Hanahan kom ua tau zoo ntawm kev hloov pauv. DH5 Alpha cell muaj peb qhov kev hloov pauv txawv: recA1, endA1, thiab lacZΔM15. recA1 yog ib qho kev hloov pauv uas hloov glycine 160 nrog thiab aspartic acid residue hauv recA polypeptide. Qhov kev hloov pauv no cuam tshuam cov haujlwm ntawm recombinases thiab inactivates homologous recombination. endA1 mutation inactivates ib qho intracellular endonuclease uas tiv thaiv nws los ntawm degrading lub plasmid tso.
Daim duab 02: DH5 Alpha
Ntxiv mus, lacZΔM15 kev hloov pauv ua rau kev tshuaj ntsuam xiav-dawb ntawm cov hlwb hloov pauv. Cov hlwb no yog cov hlwb muaj peev xwm. Lawv feem ntau siv nrog calcium chloride transformation los ntxig rau qhov xav tau plasmid. Nws tau raug txheeb xyuas los ntawm kev tshawb fawb tsis ntev los no tias DH5 Alpha cell nrog Hanahan txoj kev yog lub cell muaj peev xwm tshaj plaws rau kev hloov pauv plasmid.
Dab tsi yog qhov zoo sib xws ntawm BL21 thiab DH5 Alpha?
- BL21 thiab DH5 Alpha yog ob txoj kev tsim kho caj ces E.coli
- Ob leeg yog cov hlwb muaj peev xwm.
- Lawv muaj kev hloov pauv txawv.
- Ob leeg tsis muaj chaw nyob.
- Cov no yog siv rau lub hom phiaj hauv chav kuaj xws li kev tshawb fawb qhia thiab cov txheej txheem cloning.
Qhov txawv ntawm BL21 thiab DH5 Alpha yog dab tsi?
BL21 yog ib qho kev tsis txaus ntawm cov tshuaj genetic engineered muaj peev xwm E. coli cell feem ntau siv rau kev qhia cov protein. Ntawm qhov tod tes, DH5 Alpha yog cov kws tsim kho caj ces muaj peev xwm E. coli cell nrog recA1 kev hloov pauv feem ntau siv rau kev hloov pauv plasmid. Yog li, qhov no yog qhov sib txawv tseem ceeb ntawm BL21 thiab DH5 Alpha. Tsis tas li ntawd, BL21 E. coli cell tsis muaj kev hloov pauv recA1, thaum DH5 Alpha E. coli cell muaj kev hloov pauv recA1.
Cov infographic hauv qab no teev qhov sib txawv ntawm BL21 thiab DH5 Alpha hauv daim ntawv teev npe.
Summary – BL21 vs DH5 Alpha
Cov kab mob uas tsis yog kab mob ntawm E. coli yog cov noob caj noob ces tsim los ntawm cov kws tshawb fawb rau kev tshawb fawb hauv chav kuaj thiab lub hom phiaj cloning. BL21 thiab DH5 Alpha yog ob lub noob caj noob ces E. coli hlwb. BL21 feem ntau yog siv rau kev tshawb fawb txog cov protein. Ntawm qhov tod tes, DH5 Alpha feem ntau yog siv rau plasmid transformation hom phiaj. Yog li, qhov no yog cov ntsiab lus ntawm qhov sib txawv ntawm BL21 thiab DH5 Alpha.
