Journal of Bacteriology, February 2001, p. 1032-1037, Vol. 183, No. 3
0021-9193/01/$04.00+0 DOI: 10.1128/JB.183.3.1032-1037.2001
Copyright © 2001, American Society for Microbiology. All rights reserved.
Centro Nacional de Biotecnología CSIC, 28049 Madrid, Spain
Received 21 September 2000/Accepted 4 November 2000
The ptsN gene of Pseudomonas putida encodes
IIANtr, a protein of the phosphoenol pyruvate:sugar
phosphotransferase (PTS) system which is required for the C source
inhibition of the
54-dependent promoter Pu
of the TOL (toluate degradation) plasmid pWW0. Using two-dimensional
gel electrophoresis, we have examined the effect of ptsN
disruption on the general expression pattern of P. putida.
To this end, cells were grown in the presence or absence of glucose,
and a 1,117-spot subset of the P. putida proteome was used
as a reference for comparisons. Among all gene products whose
expression was lowered by this carbon source (247 spots [about
22%]), only 6 behaved as Pu (i.e., were depressed in the ptsN background). This evidenced only a minor role for
IIANtr in the extensive inhibition of gene expression in
P. putida caused by glucose. However, the same experiments
revealed a large incidence of glucose-independent effects brought about
by the ptsN mutation. As many as 108 spots (ca. 9% of the
cell products analyzed) were influenced, positively or negatively, by
the loss of IIANtr. By matching this pattern with that of
an rpoN::
Km strain of P. putida,
which lacks the
54 protein, we judge that most proteins
whose expression was affected by ptsN were unrelated to the
alternative sigma factor. These data suggest a role of
IIANtr as a general regulator, independent of the presence
of repressive carbon sources and not limited to
54-dependent genes.
This article has been cited by other articles:
| Appl. Environ. Microbiol. | Infect. Immun. | Eukaryot. Cell |
|---|---|---|
| Mol. Cell. Biol. | J. Virol. | Microbiol. Mol. Biol. Rev. |
| ALL ASM JOURNALS |