Table 2.
Potential hydrogen bonds in the B1 subsite and C-terminal regions
| RNase A·Uvana |
RNase ZF-3e |
hAngb |
RNase ZF-1a |
||||
|---|---|---|---|---|---|---|---|
| Bond | Length (Å) | Bond | Length (Å) | Bond | Length (Å) | Bond | Length (Å) |
| A. Pyrimidine binding and mimicry | |||||||
| Thr45 N–O2 Ura | 2.88 | Thr49 N–Cl CL1 | 3.18 | Thr44 N–Oε1 Gln117 | 2.87 | Thr51 N–Oε2 Glu122 | 2.91 |
| Ura N3–Oγ1 Thr45 | 2.79 | Wat79 O–Oγ1 Thr49 | 3.07 | Gln117 Nε2–Oγ1 Thr44 | 3.09 | Thr51 Oγ1–Oε1 Glu122 | 2.64 |
| Thr45 Oγ1–Oδ1 Asp83 | 2.71 | Thr49 Oγ1–Oγ1 Thr86 | 3.42 | Thr44 Oγ1–Oγ1 Thr80 | 2.84 | – | – |
| His12 Nδ1–O Thr45 | 2.69 | His16 Nδ1–O Thr49 | 2.91 | His13 Nδ1–O Thr44 | 2.93 | His16 Nδ1–O Thr51 | 2.80 |
| B. Stabilisation of C-terminal conformation | |||||||
| (a) Interactions with external regions | |||||||
| Ile107 N–O Ala122 | 2.73 | Val110 N–O Arg123 | 2.80 | – | – | – | – |
| Ala122 N–O Ile107 | 3.26 | Arg123 N–O Val110 | 3.37 | – | – | – | – |
| His105 N–O Val124 | 2.82 | Lys108 N–O Val125 | 2.99 | – | – | – | – |
| Val124 N–O His105 | 2.78 | Val125 N–O Lys108 | 2.90 | – | – | – | – |
| Lys66 N–Oδ2 Asp121 | 2.81 | – | – | – | – | – | – |
| Lys66 Nζ–O Asp121 | 2.67 | – | – | – | – | – | – |
| – | – | Arg107 Nη1–O Gly124 | 2.88 | – | – | Arg106 Nη1–Oδ1 Asp123 | 2.92 |
| – | – | – | – | – | – | Arg106 Nη2–Oδ2 Asp123 | 2.96 |
| – | – | – | – | – | – | Lys85 Nζ–Oδ2 Asp123 | 3.18 |
| – | – | – | – | – | – | Lys85 Nζ–Oδ1 Asn126 | 2.77 |
| (b) Internal interactions | |||||||
| His119 Nε2–Oδ1 Asp121 | 2.66 | – | – | – | – | – | – |
| – | – | – | – | Phe120 N–O Gln117 | 2.97 | – | – |
| – | – | – | – | Arg121 N–O Ser118 | 3.14 | Asn126 Nδ2–O Asp123 | 2.73 |
| – | – | – | – | Ser118 N–Oδ1 Asp116 | 3.07 | – | – |
| – | – | – | – | Ser118 Oγ–Oδ1 Asp116 | 2.46 | – | – |