Sensitivity-enhanced Four-dimensional Amide-amide Correlation NMR Experiments for Sequential Assignment of Proline-rich Disordered Proteins.
Sensitivity-enhanced Four-dimensional Amide-amide Correlation NMR Experiments for Sequential Assignment of Proline-rich Disordered Proteins.
J Am Chem Soc. 2018 Feb 28;:
Authors: Wong LE, Maier J, Wienands J, Becker S, Griesinger C
Abstract
Proline is prevalent in intrinsically disordered proteins (IDPs). NMR assignment of proline-rich IDPs is a challenge due to low dispersion of chemical shifts. We propose here new sensitivity-enhanced 4D NMR experiments that correlate two pairs of amide resonances that are either consecutive (NHi-1, NHi) or flanking a proline at position i-1 (NHi-2, NHi). The maximum two-fold enhancement of sensitivity is achieved by employing two coherence order-selective (COS) transfers incorporated unconventionally into the pulse sequence. Each COS transfer confers an enhancement over amplitude-modulated transfer by a factor of ?2 specifically when transverse relaxation is slow. The experiments connect amide resonances over a long fragment of sequence interspersed with proline. When this method was applied to the proline-rich region of B cell adaptor protein SLP-65 (pH 6.0) and ?-synuclein (pH 7.4), which contain a total of 52 and 5 prolines, respectively, 99 % and 92 % of their non-prolyl amide resonances have been successfully assigned, demonstrating its robustness to address the assignment problem in large proline-rich IDPs.
PMID: 29489342 [PubMed - as supplied by publisher]
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