Measuring rapid hydrogen exchange in the homodimeric 36 kDa HIV-1 integrase catalytic core domain.

ABSTRACT: Measurements of rapid hydrogen exchange (HX) of water with protein amide sites contain valuable information on protein structure and function, but current NMR methods for measuring HX rates are limited in their applicability to large protein systems. An alternate method for measuring rapid HX is presented that is well-suited for larger proteins, and we apply the method to the deuterated, homodimeric 36 kDa HIV-1 integrase catalytic core domain (CCD). Using long mixing times for water-amide magnetization exchange at multiple pH values, HX rates spanning more than four orders of magnitude were measured, as well as NOE cross-relaxation rates to nearby exchangeable protons. HX protection factors for the CCD are found to be large (>10(4)) for residues along the dimer interface, but much smaller

SUBMITTER: Fitzkee NC 

PROVIDER: S-EPMC3064830 | biostudies-literature | 2011 Mar

REPOSITORIES: biostudies-literature