A large decrease in heat-shock-induced proteolysis after tryptophan starvation leads to increased expression of phage lambda lysozyme cloned in Escherichia coli.

P Soumillion; J Fastrez

doi:10.1042/bj2860187

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A large decrease in heat-shock-induced proteolysis after tryptophan starvation leads to increased expression of phage lambda lysozyme cloned in Escherichia coli.

P Soumillion·J Fastrez

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Abstract

The R gene coding for phage lambda lysozyme (lambda L), cloned under the control of the PL promoter on a multicopy vector, is expressed in an Escherichia coli strain auxotrophic for tryptophan. Induction by a thermal shift after tryptophan supplementation in a culture initially brought into stationary phase by tryptophan starvation leads to highly increased expression. A thermally unstable mutant protein, difficult to obtain under standard conditions, can be easily produced by post-stationary-phase expression. It is shown that this is due to a drastic decrease in the heat-shock-induced proteolysis normally observed on thermal induction. These data are discussed in relation to our present knowledge of stringent and heat-shock responses.

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Bacteriophage lambda Chloramphenicol Escherichia coli Gene Expression Regulation, Bacterial Gene Expression Regulation, Enzymologic Hot Temperature Kinetics Muramidase Recombinant Proteins Temperature Tryptophan Journal Article Research Support, Non-U.S. Gov't

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P Soumillion, J Fastrez. 1992-08-15. A large decrease in heat-shock-induced proteolysis after tryptophan starvation leads to increased expression of phage lambda lysozyme cloned in Escherichia coli.. https://doi.org/10.1042/bj2860187

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