J . Am. Chem. SOC.1991, 113, 676-678
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tturnber of Inner sphere H20 molecules xB with number of H 2 0 molecules (6-n) in the inner coordination sphere of Mg2+. Data shown corresponds to A T P (O), ADP3- ( O ) , glucose I-phosphate (+), glucose 6-phosphate (H), tRNAPhc[native (A)and nonnative (V)conformations], and 5s rRNA (0). Values for xB (&IO%) were determined by line-shape analysis of data determined by systematic titration and variable-temperature experiments, and from relaxation measurements.8J1*2' Figure 2. Variation of
are added to a 0.22 m M solution of Escherichia coli 5s rRNA. A resonance was observed after the addition of 1 equiv of magnesium, and so in contrast to most tRNAs, 5s rRNA does not possess strong Mg2+binding sites (Le., K , are all
