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A bacterial clone synthesizing proinsulin.

L Villa-Komaroff·A Efstratiadis·S Broome·P Lomedico·R Tizard·S P Naber·W L Chick·W Gilbert
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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.

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Base SequenceDNA Restriction EnzymesDNA, BacterialDNA, RecombinantEscherichia coliInsulinPenicillinasePlasmidsProinsulinJournal ArticleResearch Support, U.S. Gov't, P.H.S.

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L Villa-Komaroff, A Efstratiadis, S Broome, P Lomedico, R Tizard, S P Naber, W L Chick, W Gilbert. 1978. A bacterial clone synthesizing proinsulin.. https://doi.org/10.1073/pnas.75.8.3727

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