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Enhanced phosphoserine insertion during Escherichia coli protein synthesis via partial UAG codon reassignment and release factor 1 deletion.

ABSTRACT: Genetically encoded phosphoserine incorporation programmed by the UAG codon was achieved by addition of engineered elongation factor and an archaeal aminoacyl-tRNA synthetase to the normal Escherichia coli translation machinery (Park et al., 2011) Science 333, 1151). However, protein yield suffers from expression of the orthogonal phosphoserine translation system and competition with release factor 1 (RF-1). In a strain lacking RF-1, phosphoserine phosphatase, and where seven UAG codons residing in essential genes were converted to UAA, phosphoserine incorporation into GFP and WNK4 was significantly elevated, but with an accompanying loss in cellular fitness and viability.

SUBMITTER: Heinemann IU

PROVIDER: S-EPMC3473164 | biostudies-literature | 2012 Oct

REPOSITORIES: biostudies-literature

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Enhanced phosphoserine insertion during Escherichia coli protein synthesis via partial UAG codon reassignment and release factor 1 deletion.

Heinemann Ilka U IU Rovner Alexis J AJ Aerni Hans R HR Rogulina Svetlana S Cheng Laura L Olds William W Fischer Jonathan T JT Söll Dieter D Isaacs Farren J FJ Rinehart Jesse J

FEBS letters 20120913 20

Genetically encoded phosphoserine incorporation programmed by the UAG codon was achieved by addition of engineered elongation factor and an archaeal aminoacyl-tRNA synthetase to the normal Escherichia coli translation machinery (Park et al., 2011) Science 333, 1151). However, protein yield suffers from expression of the orthogonal phosphoserine translation system and competition with release factor 1 (RF-1). In a strain lacking RF-1, phosphoserine phosphatase, and where seven UAG codons residing ...[more]

PMID: 22982858

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