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Updated: Aug 8, 2026

Production of Disulfide-stabilized Transmembrane Peptide Complexes for Structural Studies
Published on: March 6, 2013
Human metallothionein-II is synthesized as a stable membrane-localized fusion protein in Escherichia coli
F A Jacobs1, F M Romeyer, M Beauchemin
1Biotechnology Research Institute (NRCC), Montreal, Quebec, Canada.
Abstract:
A synthetic gene encoding human metallothionein-II (HMT) was cloned into the specially constructed high-copy-number expression vector, pUA7, and expressed in Escherichia coli. The plasmid construct includes the promoter/operator and regulatory sequences of the Salmonella typhimurium ara operon and part of the 5'-coding and all of the 3'-noncoding regions of the E. coli lpp. Upon induction with arabinose, the resulting Lpp::HMT fusion protein was produced 75,000-fold over uninduced cells, with a relatively stable mRNA (T1/2 of 8.3 min) and a completely stable protein. In addition, over 95% of the final fusion protein was localized in the outer membrane and was capable of binding heavy metals (especially cadmium) in vitro. Cells producing Lpp::HMT bioaccumulated heavy metals (e.g., cadmium) 66-fold over nonproducing cells.
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