Structural highlights
Publication Abstract from PubMed
NMR spectroscopy has revealed pH-dependent structural changes in the highly conserved catalytic domain 5 of a bacterial group II intron. Two adenines with pK(a) values close to neutral pH were identified in the catalytic triad and the bulge. Protonation of the adenine opposite to the catalytic triad is stabilized within a G(syn)-AH(+) (anti) base pair. The pH-dependent anti-to-syn flipping of this G in the catalytic triad modulates the known interaction with the linker region between domains 2 and 3 (J23) and simultaneously the binding of the catalytic Mg(2+) ion to its backbone. Hence, this here identified shifted pK(a) value controls the conformational change between the two steps of splicing.
Protonation-Dependent Base Flipping at Neutral pH in the Catalytic Triad of a Self-Splicing Bacterial Group II Intron.,Pechlaner M, Donghi D, Zelenay V, Sigel RK Angew Chem Int Ed Engl. 2015 Aug 10;54(33):9687-90. doi: 10.1002/anie.201504014. , Epub 2015 Jun 26. PMID:26119804[1]
From MEDLINE®/PubMed®, a database of the U.S. National Library of Medicine.
References
- ↑ Pechlaner M, Donghi D, Zelenay V, Sigel RK. Protonation-Dependent Base Flipping at Neutral pH in the Catalytic Triad of a Self-Splicing Bacterial Group II Intron. Angew Chem Int Ed Engl. 2015 Aug 10;54(33):9687-90. PMID:26119804 doi:10.1002/anie.201504014