Construction and characterization of an unmarked aroC deletion mutant of Burkholderia pseudomallei strain A2

Southeast Asian J Trop Med Public Health. 2009 Jan;40(1):123-30.

Abstract

Using a sucrose counter-selection strategy, we have constructed an unmarked aroC deletion mutant of B. pseudomallei strain A2 in order to investigate the possibility of an effective live-attenuated vaccine. The aroC deletion in the resultant mutant, designated A2DeltaaroC, was confirmed by PCR, Southern hybridization and failure of the mutant to grow in a defined medium without aromatic compounds. Compared to the parental wild type strain, A2DeltaaroC was highly attenuated for virulence following intraperitoneal introduction into BALB/c and C57BL/6 mice. BALB/c mice immunized intraperitoneally with A2DeltaaroC were not protected against a challenge dose of 500 cfu (25 x LD50) of the parental strain A2, whereas C57BL/6 mice similarly immunized intraperitoneally with A2DeltaaroC were significantly protected against a challenge dose of 6,000 cfu (20 x LD50).

Publication types

  • Research Support, Non-U.S. Gov't

MeSH terms

  • Animals
  • Bacterial Vaccines / genetics*
  • Bacterial Vaccines / immunology
  • Base Sequence
  • Blotting, Southern
  • Burkholderia pseudomallei / genetics
  • Burkholderia pseudomallei / immunology*
  • Burkholderia pseudomallei / isolation & purification
  • Burkholderia pseudomallei / pathogenicity
  • Female
  • Gene Deletion*
  • Immunization
  • Injections, Intraperitoneal
  • Melioidosis / prevention & control*
  • Mice
  • Mice, Inbred BALB C
  • Mice, Inbred C57BL
  • Phosphorus-Oxygen Lyases / genetics*
  • Polymerase Chain Reaction
  • Sequence Deletion
  • Vaccines, Attenuated / administration & dosage
  • Vaccines, Attenuated / genetics*
  • Vaccines, Attenuated / immunology
  • Virulence / genetics

Substances

  • Bacterial Vaccines
  • Vaccines, Attenuated
  • chorismate synthase
  • Phosphorus-Oxygen Lyases