학술논문
An intraresidual i(HCA)CO(CA)NH experiment for the assignment of main-chain resonances in 15.sup.N, 13.sup.C labeled proteins
Document Type
Report
Source
Journal of Biomolecular NMR. Nov, 2009, Vol. 45 Issue 3, p301, 10 p.
Subject
Language
English
ISSN
0925-2738
Abstract
An improved pulse sequence, intraresidual i(HCA)CO(CA)NH, is described for establishing solely 13.sup.C (i), 15.sup.N(i), 1.sup.H.sup.N(i) connectivities in uniformly 15.sup.N/ [.sup.13]C-labeled proteins. In comparison to the "out-and-back" style intra-HN(CA)CO experiment, the new pulse sequence offers at least two-fold higher experimental resolution in the 13.sup.C dimension and on average 1.6 times higher sensitivity especially for residues in [alpha]-helices. Performance of the new experiment was tested on a small globular protein ubiquitin and an intrinsically unfolded 110-residue cancer/testis antigen CT16/PAGE5. Use of intraresidual i(HCA)CO(CA)NH experiment in combination with the established HNCO experiment was crucial for the assignment of highly disordered CT16.