The bacterial phosphoenolpyruvate:sugar phosphotransferase system regulates a variety of physiological processes as well as
effecting sugar transport. The crr gene product (enzyme IIA Glc (IIA Glc )) ...mediates some of these regulatory phenomena. In this report, we characterize a novel IIA Glc -binding protein from Escherichia coli extracts, discovered using ligand-fishing with surface plasmon resonance spectroscopy. This protein, which we named FrsA
( f ermentation/ r espiration s witch protein), is the 47-kDa product of the yafA gene, previously denoted as âfunction unknown.â FrsA forms a 1:1 complex specifically with the unphosphorylated form of IIA Glc , with the highest affinity of any protein thus far shown to interact with IIA Glc . Orthologs of FrsA have been found to exist only in facultative anaerobes belonging to the γ-proteobacterial group. Disruption
of frsA increased cellular respiration on several sugars including glucose, while increased FrsA expression resulted in an increased
fermentation rate on these sugars with the concomitant accumulation of mixed-acid fermentation products. These results suggest
that IIA Glc regulates the flux between respiration and fermentation pathways by sensing the available sugar species via a phosphorylation
state-dependent interaction with FrsA.
... controls expression of heat shock genes in Escherichia coli and is widely distributed in proteobacteria. The distinguishing feature of ... promoters is a long -10 region (CCCCATNT) whose tetra-C ...motif is important for promoter activity. Using alanine-scanning mutagenesis of ... and in vivo and in vitro assays, we identified promoter recognition determinants of this motif. The most downstream C (-13) is part of the -10 motif; our work confirms and extends recognition determinants of -13C. Most importantly, our work suggests that the two upstream Cs (-16, -15) constitute an 'extended -10' recognition motif that is recognized by K130, a residue universally conserved in β- and g-proteobacteria. This residue is located in the α-helix of ...Domain 3 that mediates recognition of the extended -10 promoter motif in other ... K130 is not conserved in α- and ...-proteobacteria and we found that ... from the α- proteobacterium Caulobacter crescentus does not need the extended -10 motif for high promoter activity. This result supports the idea that K130 mediates extended -10 recognition. ... is the first Group 3 ... shown to use the 'extended -10' recognition motif. (ProQuest: ... denotes formulae/symbols omitted.)
... controls the expression of flagella-related genes and is the most widely distributed alternative s factor, present in motile Gram-positive and Gram-negative bacteria. The distinguishing feature ...of ... promoters is a long -10 region (GCCGATAA). Despite the fact that the upstream GC is highly conserved, previous studies have not indicated a functional role for this motif. Here we examine the functional relevance of the GCCG motif and determine which residues in ... participate in its recognition. We find that the GCCG motif is a functionally important composite element. The upstream GC constitutes an extended -10 motif and is recognized by R91, a residue in Domain 3 of ... The downstream CG is the upstream edge of -10 region of the promoter; two residues in Region 2.4, D81 and R84, participate in its recognition. Consistent with their role in base-specific recognition of the promoter, R91, D81 and D84 are universally conserved in ... orthologues. s28 is the second Group 3 s shown to use an extended -10 region in promoter recognition, raising the possibility that other Group 3 ... will do so as well. (ProQuest: ... denotes formulae/symbols omitted.)
Summarys32 controls expression of heat shock genes in Escherichia coli and is widely distributed in proteobacteria. The distinguishing feature of s32 promoters is a long -10 region (CCCCATNT) whose ...tetra-C motif is important for promoter activity. Using alanine-scanning mutagenesis of s32 and in vivo and in vitro assays, we identified promoter recognition determinants of this motif. The most downstream C (-13) is part of the -10 motif; our work confirms and extends recognition determinants of -13C. Most importantly, our work suggests that the two upstream Cs (-16, -15) constitute an 'extended -10' recognition motif that is recognized by K130, a residue universally conserved in b- and g-proteobacteria. This residue is located in the a-helix of sDomain 3 that mediates recognition of the extended -10 promoter motif in other ss. K130 is not conserved in a- and d-/e-proteobacteria and we found that s32 from the a-proteobacterium Caulobacter crescentus does not need the extended -10 motif for high promoter activity. This result supports the idea that K130 mediates extended -10 recognition. s32 is the first Group 3 s shown to use the 'extended -10' recognition motif.
Summary
σ
32
controls expression of heat shock genes in
Escherichia coli
and is widely distributed in proteobacteria. The distinguishing feature of σ
32
promoters is a long −10 region (CCCCATNT) ...whose tetra‐C motif is important for promoter activity. Using alanine‐scanning mutagenesis of σ
32
and
in vivo
and
in vitro
assays, we identified promoter recognition determinants of this motif. The most downstream C (−13) is part of the −10 motif; our work confirms and extends recognition determinants of −13C. Most importantly, our work suggests that the two upstream Cs (−16, −15) constitute an ‘extended −10’ recognition motif that is recognized by K130, a residue universally conserved in β‐ and γ‐proteobacteria. This residue is located in the α‐helix of σDomain 3 that mediates recognition of the extended −10 promoter motif in other σs. K130 is not conserved in α‐ and δ‐/ε‐proteobacteria and we found that σ
32
from the α‐proteobacterium
Caulobacter crescentus
does not need the extended −10 motif for high promoter activity. This result supports the idea that K130 mediates extended −10 recognition. σ
32
is the first Group 3 σ shown to use the ‘extended −10’ recognition motif.
Summarys28 controls the expression of flagella-related genes and is the most widely distributed alternative s factor, present in motile Gram-positive and Gram-negative bacteria. The distinguishing ...feature of s28 promoters is a long -10 region (GCCGATAA). Despite the fact that the upstream GC is highly conserved, previous studies have not indicated a functional role for this motif. Here we examine the functional relevance of the GCCG motif and determine which residues in s28 participate in its recognition. We find that the GCCG motif is a functionally important composite element. The upstream GC constitutes an extended -10 motif and is recognized by R91, a residue in Domain 3 of s28. The downstream CG is the upstream edge of -10 region of the promoter; two residues in Region 2.4, D81 and R84, participate in its recognition. Consistent with their role in base-specific recognition of the promoter, R91, D81 and D84 are universally conserved in s28 orthologues. s28 is the second Group 3 s shown to use an extended -10 region in promoter recognition, raising the possibility that other Group 3 ss will do so as well.
Summary
σ
28
controls the expression of flagella‐related genes and is the most widely distributed alternative σ factor, present in motile Gram‐positive and Gram‐negative bacteria. The distinguishing ...feature of σ
28
promoters is a long −10 region (GCCGATAA). Despite the fact that the upstream GC is highly conserved, previous studies have not indicated a functional role for this motif. Here we examine the functional relevance of the GCCG motif and determine which residues in σ
28
participate in its recognition. We find that the GCCG motif is a functionally important composite element. The upstream GC constitutes an extended −10 motif and is recognized by R91, a residue in Domain 3 of σ
28
. The downstream CG is the upstream edge of −10 region of the promoter; two residues in Region 2.4, D81 and R84, participate in its recognition. Consistent with their role in base‐specific recognition of the promoter, R91, D81 and D84 are universally conserved in σ
28
orthologues. σ
28
is the second Group 3 σ shown to use an extended −10 region in promoter recognition, raising the possibility that other Group 3 σs will do so as well.
σ
28
controls the expression of flagella related genes and is the most widely distributed alternative σ factor, present in motile gram-positive and gram-negative bacteria. The distinguishing feature ...of σ
28
promoters is a long −10 region (GCCGATAA). Despite the fact that the upstream GC is highly conserved, previous studies have not indicated a functional role for this motif. Here we examine the functional relevance of the GCCG motif and determine which residues in σ
28
participate in its recognition. We find that the GCCG motif is a functionally important composite element. The upstream GC constitutes an extended −10 motif and is recognized by R91, a residue in Domain 3 of σ
28
. The downstream CG is the upstream edge of −10 region of the promoter; two residues in Region 2.4, D81 and R84, participate in its recognition. Consistent with their role in base-specific recognition of the promoter, R91, D81 and D84 are universally conserved in σ
28
orthologues. σ
28
is the second Group 3 σ shown to use an extended −10 region in promoter recognition, raising the possibility that other Group 3 σs will do so as well.
Vibrio vulnificus is an opportunistic human pathogen that causes severe infections in susceptible individuals. While the components of the
Escherichia coli phosphoenolpyruvate: sugar ...phosphotransferase system (PTS) have been shown to regulate numerous targets, little such information is available for the
V. vulnificus PTS. Here we show that enzyme IIA
Glc of the PTS regulates the peptidase activity of a mammalian insulysin homolog in
V. vulnificus. While interaction of IIA
Glc with the insulysin homolog is independent of the phosphorylation state of IIA
Glc, only unphosphorylated IIA
Glc activates the insulysin homolog. Taken together, our results suggest that the
V. vulnificus insulysin-IIA
Glc complex plays a role in survival in the host by sensing glucose.
MINT-
8045996:
IIA glu (uniprotkb:Q7MBY2)
binds (MI:
0407) to
vIDE (uniprotkb:
Q7MIS6) by
pull down (MI:
0096)
MINT-
8045817, MINT-
8045967:
IIA glu (uniprotkb:Q7MBY2)
physically interacts (MI:
0915) with
vIDE (uniprotkb:
Q7MIS6) by
pull down (MI:
0096)
While the proteins of the phosphoenolpyruvate:carbohydrate phosphotransferase system (carbohydrate PTS) have been shown to regulate numerous targets,little such information is available for the ...nitrogen-metabolic phosphotransferase system (nitrogen-metabolic PTS). To elucidate the physiological role of the nitrogen-metabolic PTS, we carried out phenotype microarray (PM) analysis with Escherichia coli K-12 strain MG1655 deleted for the ptsP gene encoding the first enzyme of the nitrogen-metabolic PTS. Together with the PM data, growth studies revealed that a ptsN (encoding enzyme IIA^sup Ntr^) mutant became extremely sensitive to leucine-containing peptides (LCPs), while both ptsP (encoding enzyme I^sup Ntr^) and ptsO (encoding NPr) mutants were more resistant than wild type. The toxicity of LCPs was found to be due to leucine and the dephospho-form of enzyme IIA^sup Ntr^ was found to be necessary to neutralize leucine toxicity. Further studies showed that the dephospho-form of enzyme IIA^sup Ntr^ is required for derepression of the ilvBN operon encoding acetohydroxy acid synthase I catalysing the first step common to the biosynthesis of the branched-chain amino acids. PUBLICATION ABSTRACT
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