The use of Escherichia coli bearing a phoN gene for the removal of uranium and nickel from aqueous flows

G. Basnakova, E. R. Stephens, M. C. Thaller, G. M. Rossolini, L. E. Macaskie

Research output: Contribution to journalArticlepeer-review


A Citrobacter sp. originally isolated from metal-polluted soil accumulates heavy metals via metalphosphate deposition utilizing inorganic phosphate liberated via PhoN phosphatase activity. Further strain development was limited by the non-transformability of this environmental isolate. Recombinant Escherichia coli DH5α bearing cloned phoN or the related phoC acquired metal-accumulating ability, which was compared with that of the Citrobacter sp. with respect to removal of uranyl ion (UO22+) from dilute aqueous flows and its deposition in the form of polycrystalline hydrogen uranyl phosphate (HUO2PO4). Subsequently, HUO2PO4-laden cells removed Ni2+ from dilute aqueous flows via intercalation of Ni2+ into the HUO2PO4 lattice. Despite comparable acid phosphatase activity in all three strains, the E. coli DH5α (phoC) construct was superior to Citrobacter N14 in both uranyl and nickel accumulation, while the E. coli DH5α (phoN) construct was greatly inferior in both respects. Expression of phosphatase activity alone is not the only factor that permits efficient and prolonged metal phosphate accumulation, and the data highlight possible differences in the PhoN and PhoC phosphatases, which are otherwise considered to be related in many respects.

Original languageEnglish
Pages (from-to)266-272
Number of pages7
JournalApplied Microbiology and Biotechnology
Issue number2
Publication statusPublished - 1998

ASJC Scopus subject areas

  • Biotechnology
  • Bioengineering
  • Microbiology


Dive into the research topics of 'The use of Escherichia coli bearing a phoN gene for the removal of uranium and nickel from aqueous flows'. Together they form a unique fingerprint.

Cite this