(A) Analysis of cell-free-generated peptidyl-tRNAs bearing N-terminal portions of the amino acid sequence of apoMb by low pH TA (Lanes 1, 2, 5 and 6) and reference pH TT (Lanes 3, 4, 7, and 8) SDS PAGE. All ribosome-associated nascent apoMb polypeptides were N-terminally labeled with BODIPYFL-Met-tRNAfMet. Bands corresponding to nascent polypeptides covalently linked to tRNA and tRNA-released by treatment with puromycin are enclosed in green and orange rectangles, respectively. (B) Diagram providing the quantitative extent of ester hydrolysis for peptidyl-tRNA run on the TA and TT gels in panel A (lanes 1, 3, 5, and 7). For each lane, the percent of ester hydrolysis was determined as the ratio of hydrolyzed product to total fluorescence intensity.