Proteomic Analyses of a Listeria monocytogenes Mutant Lacking [sigma]B Identify New Components of the [sigma]B Regulon and Highlight a Role for [sigma]B in the Utilization of Glycerol

• Published in: Applied and environmental microbiology Vol. 74; no. 3; p. 594
• Main Authors: Abram, F, Su, Wan-Lin, Wiedmann, M, Boor, K J, Coote, P, Botting, C, Karatzas, K A G, O'Byrne, C P
• Format: Journal Article
• Language: English
• Published: Washington American Society for Microbiology 01.02.2008
• Subjects: Bacteria; Bacteriology; Biochemistry; Environmental science; Mutation; Proteins; Proteomics
• ISSN: 0099-2240

In Listeria monocytogenes the alternative sigma factor ... plays important roles in both virulence and stress tolerance. In this study a proteomic approach was used to define components of the ... regulon in L. monocytogenes 10403S (serotype 1/2a). Using two-dimensional gel electrophoresis and the recently developed isobaric tags for relative and absolute quantitation technique, the protein expression profiles of the wild type and an isogenic ...sigB deletion strain were compared. Overall, this study identified 38 proteins whose expression was ... dependent; 17 of these proteins were found to require the presence of ... for full expression, while 21 were expressed at a higher level in the ...sigB mutant background. The data obtained with the two proteomic approaches showed limited overlap (four proteins were identified by both methods), a finding that highlights the complementarity of the two technologies. Overall, the proteomic data reaffirmed a role for ... in the general stress response and highlighted a probable role for ... in metabolism, especially in the utilization of alternative carbon sources. Proteomic and physiological data revealed the involvement of ... in glycerol metabolism. Five newly identified members of the ... regulon were shown to be under direct regulation of ... using reverse transcription-PCR (RT-PCR), while random amplification of cDNA ends-PCR was used to map four ...-dependent promoters upstream from lmo0796, lmo1830, lmo2391, and lmo2695. Using RT-PCR analysis of known and newly identified ...-dependent genes, as well as proteomic analyses, ... was shown to play a major role in the stationary phase of growth in complex media. (ProQuest: ... denotes formulae/symbols omitted.)