UW-Madison Dept of Bacteriology
William H. McClain
Halvorson Professor of Bacteriology, Emeritus
4554 Microbial Sciences Building
1550 Linden Drive
(608)262-3054
wmcclain@wisc.edu
Research Focus
A long-standing question is how tRNAs achieve specificity in amino acid selection during protein synthesis. The specificity of tRNA in aminoacylation (tRNA identity) depends on the tRNA's productive interaction with the correct enzyme and non-productive interaction with all other enzymes. Our laboratory is engaged in pinpointing the nucleotides responsible for tRNA identity. The results indicate that although extensive regions of the tRNA interact with the enzyme, only a small number of nucleotides comprises the major determinants of tRNA identity. They often lie in the same locations (acceptor end and anticodon) in different tRNAs. Therefore, a determinant in a given tRNA simultaneously ensures both productive and non-productive interactions with the respective enzymes. We also are identifying the key amino acids in the enzyme that guide its interaction with the correct tRNA and are elucidating the 3-D network of tRNA-enzyme interactions that configure the catalytic site in its active form.