Jul 1, 1984

Overproduction of transcription termination factor Rho in Escherichia coli

K ShigesadaM Imai


A plasmid system has been constructed which allows high-level expression of the rho gene of Escherichia coli under the control of the pL promoter and the N-antitermination regulatory system of bacteriophage lambda. The pL-directed synthesis of Rho crucially depends on the lambda N gene product and is promoted most effectively when this product is supplied from the N gene cloned on a separate compatible plasmid with a moderate copy number. The requirement for N can be circumvented partly, but not completely, by deletion of the region preceding the rho structural gene. Attempts were also made to optimize the construction of rho-expression plasmids by adjusting the orientation and location of pL and rho inserts on the pBR322 vector. With optimal conditions, Rho protein is overexpressed 100-fold and can become as much as 10% of the total cellular protein. Using this plasmid system, Rho can be purified with a yield of more than 20 mg from 10 g of induced cells.

  • References26
  • Citations23

Mentioned in this Paper

RHO gene
Alkalescens-Dispar Group
Gene Deletion Abnormality
Deletion Mutation
Genes, Bacterial
Genome Encoded Entity
Structural gene
Rho Gene (Procedure)

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