Abstract: | A procedure is described for the isolation of nascent albuminyl peptides from rat liver polysomes which is based on the isolation of total peptidyl tRNA by ion-exchange chromatography on ECTEOLA cellulose followed by immuno-affinity chromatography employing monospecific anti-albumin antibodies immobilized on Sepharose 4B. Identity of the isolated nascent albuminyl peptides was assayed by tryptic peptide fingerprint analysis. Quantitation and determination of the specific activity of the nascent albuminyl peptides, labeled in vivo with l-14c]leucine, were made by subjecting the peptides to acid hydrolysis, dansylation and resoultion of the amino acids by thin-layer chromatography, and determination of the specific activity of dansyl leucine. |