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1、194edeineEF-1graded,thedosethatproduces50%ofthemaximalresponseApoB,severalglirtamatereceptormRNAs.andWilmstumoursus-tothatdrugoragent.ceptiblegenemRNA.InthecaseofApoB,acytidineresidueisedeineanyofseveralpentapeptide-amideantibioticsdeaminatedtoauridineresiduesothatthecodonforgluta-el
2、aboratedbyastrainofBacillusbrevisandeffectiveagainstmine(CAA)becomesastopcodon(UAA);hence,translationGram-positiveandGram-negativebacteria,somefungiandresultsinashortenedformoftheprotein.othereukaryoticcells,andsomeneoplasticcells.EdeineAI,editosomeamacromolecularcomplexinvolvedinthe
3、editingNa](N-{A^-[N-(B-tyrosyl)isoseryl]-2,3-diaminopropionyl}-2,6-ofRNAtranscripts.Specificribonucleotidecomplexesincludediamino-7-hydroxyazela-9-yl)glycyl]spermidine,anditsNa-guideRNA(seegRNA),whichspecifiestheeditedsequence.amidinospermidineanalogue,edeineB1,arehighlyactive;Edmand
4、egradationaprocedureusedinsequencingtheirrespectiveconstitutionalisomers,edeinesAaandB2,(poly)peptidesinwhichamino-acidresiduesareremovedhavelowintrinsicactivity.Inintactbacteria,lowconcentra-stepwisefromtheNterminusbyreactionwithphenylisothio-tionsofedeinereversiblyinhibitDNAsynthes
5、isandenhancecyanate,QH5-N=C=S,toformthephenylthiocarbamyl-pep-RNAsynthesisbutdonotaffectproteinsynthesis.Incell-freetide(abbr.:PTC-peptide).Thisisthencleavedinanhydroussystems,edeineA]interactswithbothribosomalsubunitsacid(whichfavoursattackbythesulfuratomonthecarbonyl(preferentially
6、thesmallerone)andstronglyinhibitstransla-carbonoftheterminalpeptide)togiveathiazolinoneinterme-tion.diateandthereleaseoftheremainderofthepeptidechain.Thethiazolinoneintermediateishydrolysedtothephenylthio-carbamylderivativeoftheN-terminalaminoacid,whichthencyclizestoformthephenylthio
7、hydantoinderivative(abbr.:PTH-aminoacid).ThePTH-aminoacidisextractedintoor-ganicsolventsandidentifiedbychromatography.Thesederiv-ativeshaveastrongUV-absorptionatabout259nm,whichpermitsthemtobevisualizedagainstafluorescentscreenusinganultravioletlightsource.Astheremainderofthepep-tide
8、chainisliber