Title SALMONELLA TYPHIMURIUM RESPONSES TO A BACTERICIDAL PROTEIN FROM HUMAN
NEUTROPHILS Journal Molecular Microbiology. 17(3):523-531, 1995 Aug. ISSN 0950-382X ABS
Bactericidal/permeability-increasing protein [BPI] is a cationic antimicrobial protein from neutrophils that specifically binds
to the surfaces of Gram-negative bacteria via the lipid A component of lipopolysaccharide. To obtain information about the
responses of Salmonella typhimurium to cell-surface damage by BPI, two-dimensional gel electrophoresis and N-terminal
microsequencing were used to identify proteins that were induced or repressed following BPI treatment. The majority of the
affected proteins are involved in central metabolic processes. Upon addition of BPI, the beta-subunit of the F-1 portion of
Escherichia coil ATP synthase was repressed threefold whereas six proteins were induced up to 11-fold. Three of the latter
were identified as lipoamide dehydrogenase, enoyl-acyl carrier protein reductase, and the heat-shock protein HtpG.
Additionally, a novel protein, BipA, was identified that is induced over sevenfold by BPI; sequence analysis suggests that it
belongs to the GTPase superfamily and interacts with ribosomes. A conserved direct-repeat motif is present in the regulatory
regions of several BPI-inducible genes, including the bipA gene. Only one of the BPI-responsive proteins was induced
when cells were treated with polymyxin B, which also binds to lipid A. We therefore conclude that BPI and polymyxin B
affect different global regulatory networks in S. typhimurium even though they bind with high affinity to the same
cell-surface component. [References: 4
Bob and everyone:
There are several references, or rather at least two. This is the one I had not seen before. |
