-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1
Hello Eugene-- > I am interested in the ensemble refinement procedure described by > Schweiters & Clore in Biochem. 2007, 46, 1152-1166 to characterize the > structure and dynamics of a DNA molecule. A large number of RDC restraints > in multiple alignment media were used in the refinement described in the > article. Unfortunately, I have only NOE and coupling data at present, but > am planning to obtain SAX/LAXS data, and probably have enough sample to > obtain 1H-1H and 1H-P31 RDCs in a single alignment medium. Can anyone > comment on how may RDCs and alignment media are actually required to > accurately characterize solution dynamics? A single alignment may be sufficient, as that's as many as you can effectively expect. However, you do want to measure rdcs involving as many nuclei as possible- particularly those involved in motions you're interested in- for instance, you may not have enough to characterize sugar pucker or propeller-type motions. > How does one check on whether or > not enough restraints have been included in the refinement to accurately > characterize the dynamics? > You really can only fit the input data. But one thing you might try is to use a largish ensemble (say Ne=8), and see if you get non-random behavior. best regards-- Charles -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.10 (GNU/Linux) Comment: Processed by Mailcrypt 3.5.9 <http://mailcrypt.sourceforge.net/> iEYEARECAAYFAkxEoxsACgkQPK2zrJwS/laNxgCfVtl1KukT0CzxEtplx8y4/mKP DlsAoIMHf1NRyobqVme4kl4W1VVCmI2o =/8Y6 -----END PGP SIGNATURE-----
