ABSTRACT
The processing of the recombinant analogue of beta-lipotropin (beta-LHP) having 11 additional N-terminal amino acid residues and separated from the hormone by the processing signal, was investigated using rat adrenal secretory granule lysate as a test system of processing "in vitro". It was found that incubation of the beta-LPH analogue with secretory granule enzymes leads to its limited specific degradation with a release of native beta-endorphin. It is concluded that the additional N-terminal amino acids induced no qualitative changes in beta-LPH processing.
Subject(s)
Recombinant Proteins/biosynthesis , beta-Lipotropin/biosynthesis , Adrenal Medulla/metabolism , Amino Acid Sequence , Animals , Cattle , Cytoplasmic Granules/metabolism , Humans , Hydrolysis , Molecular Sequence Data , Plasmids , Rats , Recombinant Proteins/genetics , beta-Endorphin/analysis , beta-Lipotropin/geneticsABSTRACT
A hybrid beta-lactamase gene with a synthetic tuftsin-coding DNA fragment inserted at the Pst I-site of pBR322 plasmid has been obtained and its expression has been studied. Radioactive amino acids have been used to show that in E. coli chi 925 minicells up to 30% of newly synthesized chimeric protein is secreted into periplasm providing the tuftsin transport. After hybrid protein cleavage with CNBr, tuftsin has been isolated using ion-exchange and thin-layer chromatography.