Journal Article


C Hill
C G Gahan
R D Sleator



glutamate 5 kinase molecular sequence data pathogenicity mutation mice inbred balb c genetics chemistry metabolism listeria monocytogenes listeriosis amino acid sequence proline base sequence biosynthesis virulence culture media phosphotransferases carboxyl group acceptor pharmacology animals operon microbiology mice sodium chloride growth development sequence analysis dna

Mutations in the listerial proB gene leading to proline overproduction: effects on salt tolerance and murine infection. (2001)

Abstract The observed sensitivity of Listeria monocytogenes to the toxic proline analogue L-azetidine-2-carboxylic acid (AZ) suggested that proline synthesis in Listeria may be regulated by feedback inhibition of gamma-glutamyl kinase (GK), the first enzyme of the proline biosynthesis pathway, encoded by the proB gene. Taking advantage of the Epicurian coli mutator strain XL1-Red, we performed random mutagenesis of the recently described proBA operon and generated three independent mutations in the listerial proB homologue, leading to proline overproduction and salt tolerance when expressed in an E. coli (DeltaproBA) background. While each of the mutations (located within a conserved 26-amino-acid region of GK) was shown to confer AZ resistance (AZ(r)) on an L. monocytogenes proBA mutant, listerial transformants failed to exhibit the salt-tolerant phenotype observed in E. coli. Since proline accumulation has previously been linked to the virulence potential of a number of pathogenic bacteria, we analyzed the effect of proline overproduction on Listeria pathogenesis. However, our results suggest that as previously described for proline auxotrophy, proline hyperproduction has no apparent impact on the virulence potential of Listeria.
Collections Ireland -> University College Cork -> PubMed

Full list of authors on original publication

C Hill, C G Gahan, R D Sleator

Experts in our system

Colin Hill
University College Cork
Total Publications: 351
Cormac G M Gahan
University College Cork
Total Publications: 109
Roy D. Sleator
University College Cork
Total Publications: 44