Zogulitsa

The membrane topology of the colicin E1 channel domain adaphunziridwa ndi fluorescence resonance energy transfer (FRET).FRET idaphatikizapo ma genetic encoded amino acid (coumarin) monga wopereka komanso zotsalira za cysteine ​​​​zolumikizidwa ndi DABMI (4-(dimethylamino)phenylazophenyl-4'-maleimide) monga wolandila FRET.Zotsalira za fluorescent coumarin zidaphatikizidwa mu puloteni kudzera pa orthogonal tRNA/aminoacyl-tRNA synthetase pair yomwe idalola kuphatikizika kosankhidwa pamalo aliwonse mkati mwa domeni ya colicin.Mtundu uliwonse umakhala ndi masinthidwe oyimitsa (TAG) pakuphatikizidwa kwa coumarin ndi kusintha kwa cysteine ​​(TGT) kwa cholumikizira cha DABMI.Miyendo isanu ndi umodzi yolumikizana mkati mwa helices 1-6 idatsimikiziridwa pogwiritsa ntchito kusanthula kwa FRET kwa mayiko osungunuka komanso omangidwa ndi membrane.Deta ya FRET idawonetsa kusintha kwakukulu pamatali otalikirana pakati pa ma helice 3-6 pagulu la membrane lomwe limapereka chidziwitso chatsopano pamapangidwe omangidwa ndi nembanemba a tchanelo.Nthawi zambiri, mphamvu ya coumarin-DABMI FRET imatsika pakumangiriza kwa nembanemba, ndikumanga pa ambulera ya njira ya colicin.Njira yoyeserera ya malo otsekedwa a tchanelo idapangidwa kutengera zomwe zasindikizidwa kale komanso zomwe zidasindikizidwa kale za FRET.Chitsanzochi chikuwonetsa kukonzedwa kozungulira kwa ma helice 1-7 molunjika kuchokera ku mbali ya extracellular ndi membrane interfacial association of helices 1, 6, 7, ndi 10 kuzungulira pakati pa transmembrane hairpin yopangidwa ndi helices 8 ndi 9.