Product analysis of in vitro ribosomal protein synthesis for the assessment of kinetic parameters

For the characterization of the product distribution of in vitro ribosomal protein synthesis a new method is introduced in which radioactively labeled peptides are separated on a reversed-phase HPLC column and detected on line with a flow radioactivity monitor. Employing this procedure the kinetics of product formation under pre-steady-state conditions were measured under a variety of conditions. These measurements yield the intrinsic monomolecular rate constants for peptidyl transfer (greater than 20 s-1) and translocation (rate limiting for elongation). The usefulness of this technique for accuracy measurements is illustrated.