CLOSED-FORM OF LIGANDED GLUTAMINE-BINDING PROTEIN BY ROTATIONAL-ECHO DOUBLE-RESONANCE NMR

Rotational-echo double-resonance NMR has been used to determine intern uclear distances in the complex of glutamine-binding protein and its l igand, L-glutamine. The distances between the ligand and Tyr185 are co nsistent with the results of molecular dynamics simulations constraine d by three REDOR-determined distances to His156. This model is also co nsistent with six other REDOR-determined internuclear distances, most of which agree with values from the first report of an X-ray structure of the complex of glutamine-binding protein and L-glutamine.