Genetic design of a gene for human metallothionein II and its expression as an active fusion protein in Escherichia coli

Mitsuo Yamashita, Hidefumi Kuwata, Hidehiko Murakami, Yoshikatsu Murooka

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10 Citations (Scopus)


A synthetic DNA coding for human metallothionein II (hMT-II) was designed for efficient expression in Escherichia coli and cloned into a vector, pUEX2. Upon induction by heating, the gene for hMT-II was expressed as a fusion protein between β-galactosidase and hMT-II. The fusion protein accounted for approximately 24% of the total protein between β-galactosidase and hMT-II. The fusion protein accounted for approximatedly protein with a molecular mass of approximately 122 kDa was purified in homogeneity by washing the inclusion bodies with a solution of Triton X-100. The insoluble protein was easily solubilized in the presence of 2-mercaptoethanol and sodium dodecyl sulfate without any need for denaturants, such as urea or guanidine hydrochloride. The fused hMT-II protein bound to radioactive cadmium. A competition experiment with radioactive cadmium and various heavy metals showed that the hMT-II fusion protein had a higher affinity for Cu2+, Co2+, and Ag+ ions than Cd2+ and Zn2+ ions. Thus, we succeeded in over expression of hMT-II as an active form in E. coli.

Original languageEnglish
Pages (from-to)113-118
Number of pages6
JournalJournal of Fermentation and Bioengineering
Issue number2
Publication statusPublished - 1994
Externally publishedYes


ASJC Scopus subject areas

  • Biotechnology
  • Applied Microbiology and Biotechnology
  • Bioengineering

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