Alanine Transfer RNA Synthetase: Structure–Function Relationships and Molecular Recognition of Transfer RNA

Summary

This chapter contains sections titled:

• Introduction

• Biochemical Characterization

• Sequence Determination and Comparisons

• Delineation of Functional Domains

• Two Mutations in the Dispensable Part of the Enzyme that Affect the Catalytic Activity

• Deletion Mutants that Complement the alaS5 Allele and Not the alaS Null Allele. Furthur Evidence for Coupling between Dispensable and Indispensable Parts of the Structure

• Further Delineation of Sequences Essential for RNA Binding

• Evidence that a Sequence Important for tRNA Binding Is Close to or Within a Conserved Antigenic Site

• Amino Acid Replacements that Compensate for a Large Deletion

• Engineering the Enzyme by Introduction of a Mutation that Compensates for a Deletion

• Evidence that the 3′-End of tRNA^Ala Binds to a Site in the Adenylate Synthesis Domain

• Evidence that a Single Base Pair is a Major Determinant for Recognition of Alanine tRNA

• Evidence for Binding of the Enzyme to the Amino Acid Acceptor Helix

• Crystallization of a Small Fragment of the Enzyme

• Concluding Remarks