Recognition pattern of different bases in the active site of ribonuclease Ms--a model building study

The structure of base non-specific ribonuclease Ms from Aspergillus saitoi was predicted by sequence similarity to guanine-specific RNase T1 of known structure. In this paper the interaction pattern of binding site of RNase Ms with different nucleic acids bases is analysed using model building and energy minimisation techniques. It is shown that unspecificity of this protein can be explained only when taking into account flexibility of the base recognition loop.