F'-coded, temperature-sensitive lambda cI857 repressor gene for easy construction and regulation of lambda promoter-dependent expression systems

Construction of the Recombinant Plasmid Expressing AID under the Control of Temperature-sensitive Promoter of Bacteriophage Lambda

Background and purpose: Activation-induced cytidine deaminase (AID) is a B-cell specific enzyme responsible for somatic hypermutation (SHM) and class switch recombination (CSR) of antibody genes within the B-cell follicle of peripheral lymphoid organs. Ectopic overexpression of the enzyme leads to mutations in non-B cells and Escherichia coli (E.coli) genes. However, induction of mutations in E...

Altered temperature induction sensitivity of the lambda pR/cI857 system for controlled gene E expression in Escherichia coli.

Cell lysis of Gram-negative bacteria can be efficiently achieved by expression of the cloned lysis gene E of bacteriophage PhiX174. Gene E expression is tightly controlled by the rightward lambda pR promoter and the temperature-sensitive repressor cI857 on lysis plasmid pAW12. The resulting empty bacterial cell envelopes, called bacterial ghosts, are currently under investigation as candidate v...

Amino acid changes in the repressor of bacteriophage lambda due to temperature-sensitive mutations in its cI gene and the structure of a highly temperature-sensitive mutant repressor.

The mutant cIts genes from seven different lambdacIts phages carrying tsU50, tsU9, tsU46, ts1, tsU51, tsI-22 and ts2 mutations were cloned in plasmid. The positions of these mutations and the resulting changes of amino acids in the repressor were determined by DNA sequencing. The first four mutations mapping in the N-terminal domain show the following changes: I21S, G53S, A62T and V73A, respect...

Successful expression of a selenomethionyl protein under control of the temperature-sensitive lambda repressor requires higher than normal temperature.

Control of transcription of the repressor gene in bacteriophage lambda.

The rate of transcription of the structural gene for repressor (cI gene) in bacteriophage lambda is controlled by the amount of active repressor in the cell. When the (reversibly) thermolabile repressor in a bacterium lysogenic for lambdacI(857) is inactivated by heat, the rate of repressor gene transcription immediately falls. If the repressor is renatured, synthesis of repressor messenger is ...