Identification and characterization of di- and tripeptide transporter DtpT of Listeria monocytogenes EGD-e

J.A. Wouters, T. Hain, A. Darji, E. Hüfner, H.H. Wemekamp-Kamphuis, T. Chakraborty, T. Abee

Research output: Contribution to journalArticleAcademicpeer-review

21 Citations (Scopus)


Listeria monocytogenes is a gram-positive intracellular pathogen responsible for opportunistic infections in humans and animals. Here we identified and characterized the dtpT gene (lmo0555) of L. monocytogenes EGD-e, encoding the di- and tripeptide transporter, and assessed its role in growth under various environmental conditions as well as in the virulence of L. monocytogenes. Uptake of the dipeptide Pro-[14C]Ala was mediated by the DtpT transporter and was abrogated in a dtpT isogenic deletion mutant. The DtpT transporter was shown to be required for growth when the essential amino acids leucine and valine were supplied as peptides. The protective effect of glycine- and proline-containing peptides during growth in defined medium containing 3% NaCl was noted only in L. monocytogenes EGD-e, not in the dtpT mutant strain, indicating that the DtpT transporter is involved in salt stress protection. Infection studies showed that DtpT contributes to pathogenesis in a mouse infection model but has no role in bacterial growth following infection of J774 macrophages. These studies reveal that DptT may contribute to the virulence of L. monocytogenes
Original languageEnglish
Pages (from-to)5771-5778
JournalApplied and Environmental Microbiology
Issue number10
Publication statusPublished - 2005


  • lactococcus-lactis
  • salt tolerance
  • minimal medium
  • peptide transporter
  • high osmolarity
  • growth
  • virulence
  • system
  • genes
  • protein

Fingerprint Dive into the research topics of 'Identification and characterization of di- and tripeptide transporter DtpT of Listeria monocytogenes EGD-e'. Together they form a unique fingerprint.

Cite this