Molecular and General Genetics MGG

, Volume 253, Issue 4, pp 484–491

The Listeria monocytogenes gene ctpA encodes a putative P-type ATPase involved in copper transport

  • M. S. Francis
  • C. J. Thomas

DOI: 10.1007/s004380050347

Cite this article as:
Francis, M. & Thomas, C. Mol Gen Genet (1997) 253: 484. doi:10.1007/s004380050347


A Tn917 transposon derivative was used to construct a lacZ transcriptional fusion mutant in Listeria monocytogenes DRDC8 that displayed increased β-galactosidase activity in response to cation stress. A 4.3 kb fragment of L. monocytogenes chromosomal DNA flanking the lacZ fusion was cloned and sequenced. A 1962 bp open reading frame was identified, and designated ctpA. Analysis of the deduced 653 amino acid sequence revealed significant similarity to the family of ATP-dependent enzymes involved in copper transport in prokaryotes and eukaryotes. CtpA is distinctive by virtue of an N-terminal truncation in the domain responsible for cation binding. Growth of ctpA insertion mutants was restricted by the copper-chelating agent 8-hydroxyquinoline. DNA/RNA hybridisation studies revealed that levels of ctpA mRNA were increased following growth in media containing low and high copper concentrations. These results suggest the isolation of a region of DNA that encodes a novel copper-transporting system in L. monocytogenes.

Key words P-type ATPaseCtpAListeria monocytogenesCopper transportTranscriptional fusion

Copyright information

© Springer-Verlag Berlin Heidelberg 1997

Authors and Affiliations

  • M. S. Francis
    • 1
  • C. J. Thomas
    • 1
  1. 1.Department of Microbiology and Immunology, University of Adelaide, GPO Box 498, Adelaide, South Australia, Australia, 5005AU