We have investigated the over-production of seven membrane proteins in an Escherichia coli-bacteriophage T7 RNA polymerase expression system. In all seven cases, when expression of the target membrane protein was induced, most of the BL21(DE3) host cells died. Similar effects were also observed with expression vectors for ten globular proteins. Therefore, protein over-production in this express...

Two mutant strains of Escherichia coli BL21(DE3), called C41(DE3) and C43(DE3) and originally described by Miroux and Walker, are frequently used to overcome the toxicity associated with overexpressing recombinant proteins using the bacteriophage T7 RNA polymerase expression system. Even when the toxicity of the plasmids is so high that it prevents transformation in the strain BL21(DE3), the to...

A growing body of literature suggests that most chronic autoimmune diseases are associated with inappropriate inflammation mediated by Toll-like receptor (TLR) 3, TLR7/8, or TLR9. Therefore, research into blocking TLR activation to treat these disorders has become a hot topic. Here, we report the immunomodulatory properties of a nonstimulatory CpG-containing oligodeoxynucleotide (CpG-ODN), CpG-...

Membrane protein production is usually toxic to E. coli. However, using genetic screens strains can be isolated in which the toxicity of membrane protein production is reduced, thereby improving production yields. Best known examples are the C41(DE3) and C43(DE3) strains, which are both derived from the T7 RNA polymerase (P)-based BL21(DE3) protein production strain. In C41(DE3) and C43(DE3) mu...

The C41 cell line, which was derived from a human squamous carcinoma of the uterine cervix, has been characterized by analysis of quinacrine-banded metaphase chromosomes and study of alkaline phosphatase. C41 cells have a distinctive karyotype. They are hypodiploid, with a highly characteristic series of marker chromosomes, most of them derived by translocation or deletion. They contain no HeLa...

T. F. Stocker Climate and Environmental Physics, Physics Institute, University of Bern, Sidlerstrasse 5, CH-3012 Bern, Switzerland Tel: c41-31-6314462, Fax: c41-31-6314405 e-mail: stocker6climate.unibe.ch Abstract A review of climatic variability is given with a focus on abrupt changes during the last glacial. Evidence from palaeoclimatic archives suggests that these were most likley due to reo...

Indolicidin is an antimicrobial cationic peptide naturally present in the bovine neutrophils. In this study, transformed Escherichia coli cells were employed for greater and cost effective production of indolicidin. Four strains of E. coli [C41 (DE3), C43 (DE3), C41 (DE3) pLysS & C43 (DE3) pLysS] were transformed with recombinant plasmid pET21A carrying the indolicidin gene and were successfull...

This feeding trial was carried out to evaluate the effects of different dietary cadmium levels on growth and tissue cadmium content in juvenile parrotfish, Oplegnathus fasciatus, using cadmium chloride (CdCl2) as the cadmium source. Fifteen fish averaging 5.5±0.06 g (mean±SD) were randomly distributed into each of twenty one rectangular fiber tanks of 30 L capacity. Each tank was then randomly ...

The aim of the study was to optimize conditions for producing Salmonella Enteritidis recombinant heat shock protein 60 (rHsp60). Seven Escherichia coli host strains (Rosetta, Turner, C41, C43, Origami, BL21pLys, Rosetta pLys) were transformed by a recombinant plasmid containing Hsp60 gene from Salmonella Enteritidis, and then cultured and induced by isopropyl-beta-D-thiogalactopyranoside (IPTG)...

The DNase I binding loop (residues 38-52), the hydrophobic plug (residues 262-274), and the C terminus region are among the structural elements of monomeric (G-) actin proposed to form the intermonomer interface in F-actin. To test the proximity and interactions of these elements and to provide constraints on models of F-actin structure, cysteine residues were introduced into yeast actin either...