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Elimination of truncated recombinant protein expressed in Escherichia coli by removing cryptic translation initiation site.

ABSTRACT: Undesirable truncated recombinant protein products pose a special expression and purification challenge because such products often share similar chromatographic properties as the desired full length protein. We describe here our observation of both full length and a truncated form of a yeast protein (Gcn5) expressed in Escherichia coli, and the reduction or elimination of the truncated form by mutating a cryptic Shine-Dalgarno or START codon within the Gcn5 coding region. Unsuccessful attempts to engineer in a cryptic translation initiation site into other recombinant proteins suggest that cryptic Shine-Dalgarno or START codon sequences are necessary but not sufficient for cryptic translation in E. coli.

SUBMITTER: Jennings MJ

PROVIDER: S-EPMC4803570 | biostudies-literature | 2016 May

REPOSITORIES: biostudies-literature

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Elimination of truncated recombinant protein expressed in Escherichia coli by removing cryptic translation initiation site.

Jennings Matthew J MJ Barrios Adam F AF Tan Song S

Protein expression and purification 20151229

Undesirable truncated recombinant protein products pose a special expression and purification challenge because such products often share similar chromatographic properties as the desired full length protein. We describe here our observation of both full length and a truncated form of a yeast protein (Gcn5) expressed in Escherichia coli, and the reduction or elimination of the truncated form by mutating a cryptic Shine-Dalgarno or START codon within the Gcn5 coding region. Unsuccessful attempts ...[more]

PMID: 26739786

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