title: A bacterial clone synthesizing proinsulin.
abstract: We have cloned double-stranded cDNA copies of a rat preproinsulin messenger RNA in Escherichia coli chi1776, using the unique Pst endonuclease site of plasmid pBR322 that lies in the region encoding amino acids 181-182 of penicillinase. This site was reconstructed by inserting the cDNA with an oligo(dG)-oligo(dC) joining procedure. One of the clones expresses a fused protein bearing both insulin and penicillinase antigenic determinants. The DNA sequence of this plasmid shows that the insulin region is read in phase; a stretch of six glycine residues connects the alanine at position 182 of penicillinase to the fourth amino acid, glutamine, of rat proinsulin.
mesh_terms: D001483:Base Sequence; D004262:DNA Restriction Enzymes; D004269:DNA, Bacterial; D004274:DNA, Recombinant; D004926:Escherichia coli / Q000235:genetics; D007328:Insulin / Q000235:genetics / Q000276:immunology; D010405:Penicillinase / Q000235:genetics; D010957:Plasmids; D011384:Proinsulin / Q000096:biosynthesis / Q000235:genetics*
chemical_list: D004269:DNA, Bacterial; D004274:DNA, Recombinant; D007328:Insulin; D011384:Proinsulin; D004262:DNA Restriction Enzymes; D010405:Penicillinase