Crystallographic studies of Ni2+-bound NikR suggest that the RHH domains remain flexible when stoichiometric Ni2+ is bound at the high-affinity sites (10).
The model also contains a total of 11 nickel ions (two bound at the high-affinity sites and nine bound at the low-affinity sites), one copy of the detergent molecule CYMAL-3, and 63 water molecules.
For wild-type and R1016A/K1020A, R1113A/K1115A, and R1255A mutant proteins, >95% of the nucleosomes are bound at the highest protein concentrations, whereas ∼80% of the nucleosome signal remains unbound for R1016A/K1020A/R1255A and R1016A/K1020A/R1113A/K1115A and ∼30% for R1113A/K1115A/R1255A, at the equivalent protein concentration.
More importantly, there are many additional genes that are bound at the same high level of statistical confidence that are not bound in the low activity ChIP experiment.
The cross-correlation map of a substrate bound at the ABS exhibits high similarity to the cross-correlation map published by Cheng et al. (30), who analyzed the motions of cAMP-dependent protein kinase (PKA) in complex with a small peptide inhibitor (PDB code 1L3R) (56).
Also Mn II) release at pH 7 and 9 was not experimentally observed in our studies, presumably due to the tendency of Mn II) to stay surface bound at these higher pH conditions [26].
As BH4-containing and -deficient nNOS were expected to have the radioligand bound at the low- and the high-affinity site respectively, this observation argued strongly in favor of two identical anticooperative binding sites.
RTA3 and RTA3-C15S haveryery similar CD spectra when bound to PC/PG (50 50) vesicles, indicating that the C15S substitution does not induce significant helix unwinding in the C15S variant when bound at the surface of the membrane with high negatively charged lipid content (Fig. 4).
In addition, the performance of the lower bound approaches to that of the existing upper bound, especially at the high SNR.
These sites exhibit a significant amount of disorder and high crystallographic B factors, indicating that the Zn II) ions are not bound at high occupancy within the crystal lattice.
