Abstract:
:Solid state nmr methods were applied to the study of the motions and structural heterogeneity in polyglycine, sodium poly(L-glutamate), and poly(L-alanine). The response of both the main-chain and side-chain resonances to the addition of water was studied using static and magic-angle sample-spinning line shapes as well as the carbon spin-lattice relaxation times, the proton spin-lattice relaxation time in the rotating frame, and the proton-carbon cross-polarization time. The polyglycine motions are not drastically affected by the addition of water when the polymer is in the 3(1)-helix or the beta-sheet structure. The sodium poly(L-glutamate), however, responds to increased hydration with little motion in the main-chain carbon atoms, but considerable flexibility of the side-chain atoms. The greatest motions are reported for the C5 carbon with rotational amplitudes about the C4-C5 bond of about of 50 degrees. In addition, motions somewhat less than half this size are required closer to the main chain.
journal_name
Biopolymersjournal_title
Biopolymersauthors
Kennedy SD,Bryant RGdoi
10.1002/bip.360300705subject
Has Abstractpub_date
1990-01-01 00:00:00pages
691-701issue
7-8eissn
0006-3525issn
1097-0282journal_volume
30pub_type
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