Type 2 periplasmic binding fold superfamily; This evolutionary model and hierarchy represent ...
94-289
7.80e-63
Type 2 periplasmic binding fold superfamily; This evolutionary model and hierarchy represent the ligand-binding domains found in solute binding proteins that serve as initial receptors in the transport, signal transduction and channel gating. The PBP2 proteins share the same architecture as periplasmic binding proteins type 1 (PBP1), but have a different topology. They are typically comprised of two globular subdomains connected by a flexible hinge and bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. The origin of PBP module can be traced across the distant phyla, including eukaryotes, archebacteria, and prokaryotes. The majority of PBP2 proteins are involved in the uptake of a variety of soluble substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis. Besides transport proteins, the family includes ionotropic glutamate receptors and unorthodox sensor proteins involved in signal transduction. The substrate binding domain of the LysR transcriptional regulators and the oligopeptide-like transport systems also contain the type 2 periplasmic binding fold and thus they are significantly homologous to that of the PBP2; however, these two families are grouped into a separate hierarchy of the PBP2 superfamily due to the large number of protein sequences.
The actual alignment was detected with superfamily member cd08431:
Pssm-ID: 473866 [Multi-domain] Cd Length: 195 Bit Score: 197.11 E-value: 7.80e-63
The C-terminal substrate binding domain of LysR-type transcriptional regulator, HupR, which ...
94-289
7.80e-63
The C-terminal substrate binding domain of LysR-type transcriptional regulator, HupR, which regulates expression of the heme uptake receptor HupA; contains the type 2 periplasmic binding fold; HupR, a member of the LysR family, activates hupA transcription under low-iron conditions in the presence of hemin. The expression of many iron-uptake genes, such as hupA, is regulated at the transcriptional level by iron and an iron-binding repressor protein called Fur (ferric uptake regulation). Under iron-abundant conditions with heme, the active Fur repressor protein represses transcription of the iron-uptake gene hupA, and prevents transcriptional activation via HupR. Under low-iron conditions with heme, the Fur repressor is inactive and transcription of the hupA is allowed. This substrate-binding domain shows significant homology to the type 2 periplasmic binding proteins (PBP2), which are responsible for the uptake of a variety of substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. The PBP2 bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis.
Pssm-ID: 176122 [Multi-domain] Cd Length: 195 Bit Score: 197.11 E-value: 7.80e-63
LysR substrate binding domain; The structure of this domain is known and is similar to the ...
94-294
3.16e-21
LysR substrate binding domain; The structure of this domain is known and is similar to the periplasmic binding proteins. This domain binds a variety of ligands that caries in size and structure, such as amino acids, sugar phosphates, organic acids, metal cations, flavonoids, C6-ring carboxylic acids, H2O2, HOCl, homocysteine, NADPH, ATP, sulphate, muropeptides, acetate, salicylate, citrate, phenol- and quinolone derivatives, acetylserines, fatty acid CoA, shikimate, chorismate, homocysteine, indole-3-acetic acid, Na(I), c-di-GMP, ppGpp and hydrogen peroxide (Matilla et. al., FEMS Microbiology Reviews, fuab043, 45, 2021, 1. https://doi.org/10.1093/femsre/fuab043).
Pssm-ID: 460931 [Multi-domain] Cd Length: 205 Bit Score: 89.27 E-value: 3.16e-21
multiheme cytochrome-associated LysR family transcriptional regulator; Members of this family, ...
17-260
1.46e-10
multiheme cytochrome-associated LysR family transcriptional regulator; Members of this family, including founding member GSU2202 from Geobacter sulfurreducens PCA, are LysR family transcriptional regulators found regularly in the vicinity of multiheme cytochromes such as GSU2203, a decaheme c-type cytochrome.
Pssm-ID: 468965 [Multi-domain] Cd Length: 301 Bit Score: 60.91 E-value: 1.46e-10
transcriptional regulator, ArgP family; ArgP used to be known as IciA. ArgP is a positive ...
11-85
3.39e-04
transcriptional regulator, ArgP family; ArgP used to be known as IciA. ArgP is a positive regulator of argK. It is a negative autoregulator in presence of arginine. It competes with DnaA for oriC iteron (13-mer) binding. It activates dnaA and nrd transcription. It has been demonstrated to be part of the pho regulon (). ArgP mutants convey canavanine (an L-arginine structural homolog) sensitivity. [Cellular processes, Toxin production and resistance, DNA metabolism, DNA replication, recombination, and repair, Regulatory functions, DNA interactions]
Pssm-ID: 274509 [Multi-domain] Cd Length: 292 Bit Score: 41.44 E-value: 3.39e-04
The C-terminal substrate binding domain of LysR-type transcriptional regulator, HupR, which ...
94-289
7.80e-63
The C-terminal substrate binding domain of LysR-type transcriptional regulator, HupR, which regulates expression of the heme uptake receptor HupA; contains the type 2 periplasmic binding fold; HupR, a member of the LysR family, activates hupA transcription under low-iron conditions in the presence of hemin. The expression of many iron-uptake genes, such as hupA, is regulated at the transcriptional level by iron and an iron-binding repressor protein called Fur (ferric uptake regulation). Under iron-abundant conditions with heme, the active Fur repressor protein represses transcription of the iron-uptake gene hupA, and prevents transcriptional activation via HupR. Under low-iron conditions with heme, the Fur repressor is inactive and transcription of the hupA is allowed. This substrate-binding domain shows significant homology to the type 2 periplasmic binding proteins (PBP2), which are responsible for the uptake of a variety of substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. The PBP2 bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis.
Pssm-ID: 176122 [Multi-domain] Cd Length: 195 Bit Score: 197.11 E-value: 7.80e-63
LysR substrate binding domain; The structure of this domain is known and is similar to the ...
94-294
3.16e-21
LysR substrate binding domain; The structure of this domain is known and is similar to the periplasmic binding proteins. This domain binds a variety of ligands that caries in size and structure, such as amino acids, sugar phosphates, organic acids, metal cations, flavonoids, C6-ring carboxylic acids, H2O2, HOCl, homocysteine, NADPH, ATP, sulphate, muropeptides, acetate, salicylate, citrate, phenol- and quinolone derivatives, acetylserines, fatty acid CoA, shikimate, chorismate, homocysteine, indole-3-acetic acid, Na(I), c-di-GMP, ppGpp and hydrogen peroxide (Matilla et. al., FEMS Microbiology Reviews, fuab043, 45, 2021, 1. https://doi.org/10.1093/femsre/fuab043).
Pssm-ID: 460931 [Multi-domain] Cd Length: 205 Bit Score: 89.27 E-value: 3.16e-21
multiheme cytochrome-associated LysR family transcriptional regulator; Members of this family, ...
17-260
1.46e-10
multiheme cytochrome-associated LysR family transcriptional regulator; Members of this family, including founding member GSU2202 from Geobacter sulfurreducens PCA, are LysR family transcriptional regulators found regularly in the vicinity of multiheme cytochromes such as GSU2203, a decaheme c-type cytochrome.
Pssm-ID: 468965 [Multi-domain] Cd Length: 301 Bit Score: 60.91 E-value: 1.46e-10
The substrate binding domain of LysR-type transcriptional regulators (LTTRs), a member of the ...
94-253
2.27e-10
The substrate binding domain of LysR-type transcriptional regulators (LTTRs), a member of the type 2 periplasmic binding fold protein superfamily; This model and hierarchy represent the the substrate-binding domain of the LysR-type transcriptional regulators that form the largest family of prokaryotic transcription factor. Homologs of some of LTTRs with similar domain organizations are also found in the archaea and eukaryotic organisms. The LTTRs are composed of two functional domains joined by a linker helix involved in oligomerization: an N-terminal HTH (helix-turn-helix) domain, which is responsible for the DNA-binding specificity, and a C-terminal substrate-binding domain, which is structurally homologous to the type 2 periplasmic binding proteins. As also observed in the periplasmic binding proteins, the C-terminal domain of the bacterial transcriptional repressor undergoes a conformational change upon substrate binding which in turn changes the DNA binding affinity of the repressor. The genes controlled by the LTTRs have diverse functional roles including amino acid biosynthesis, CO2 fixation, antibiotic resistance, degradation of aromatic compounds, oxidative stress responses, nodule formation of nitrogen-fixing bacteria, synthesis of virulence factors, toxin production, attachment and secretion, to name a few. The structural topology of this substrate-binding domain is most similar to that of the type 2 periplasmic binding proteins (PBP2), which are responsible for the uptake of a variety of substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. The PBP2 bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis. Besides transport proteins, the PBP2 superfamily includes the substrate-binding domains from ionotropic glutamate receptors, LysR-like transcriptional regulators, and unorthodox sensor proteins involved in signal transduction.
Pssm-ID: 176102 [Multi-domain] Cd Length: 197 Bit Score: 59.15 E-value: 2.27e-10
The C-terminal substrate binding domain of galactose-binding protein regulator contains the ...
106-185
2.45e-05
The C-terminal substrate binding domain of galactose-binding protein regulator contains the type 2 periplasmic binding fold; Galactose-binding protein regulator (GbpR), a member of the LysR family of bacterial transcriptional regulators, regulates the expression of chromosomal virulence gene chvE. The chvE gene is involved in the uptake of specific sugars, in chemotaxis to these sugars, and in the VirA-VirG two-component signal transduction system. In the presence of an inducing sugar such as L-arabinose, D-fucose, or D-galactose, GbpR activates chvE expression, while in the absence of an inducing sugar, GbpR represses expression. The topology of this substrate-binding domain is most similar to that of the type 2 periplasmic binding proteins (PBP2), which are responsible for the uptake of a variety of substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. The PBP2 bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis.
Pssm-ID: 176126 [Multi-domain] Cd Length: 201 Bit Score: 44.19 E-value: 2.45e-05
transcriptional regulator, ArgP family; ArgP used to be known as IciA. ArgP is a positive ...
11-85
3.39e-04
transcriptional regulator, ArgP family; ArgP used to be known as IciA. ArgP is a positive regulator of argK. It is a negative autoregulator in presence of arginine. It competes with DnaA for oriC iteron (13-mer) binding. It activates dnaA and nrd transcription. It has been demonstrated to be part of the pho regulon (). ArgP mutants convey canavanine (an L-arginine structural homolog) sensitivity. [Cellular processes, Toxin production and resistance, DNA metabolism, DNA replication, recombination, and repair, Regulatory functions, DNA interactions]
Pssm-ID: 274509 [Multi-domain] Cd Length: 292 Bit Score: 41.44 E-value: 3.39e-04
The C-terminal substrate binding domain of LysR-type transcriptional regulator TdcA, which is ...
97-181
6.37e-04
The C-terminal substrate binding domain of LysR-type transcriptional regulator TdcA, which is involved in the degradation of L-serine and L-threonine, contains the type 2 periplasmic binding fold; TdcA, a member of the LysR family, activates the expression of the anaerobically-regulated tdcABCDEFG operon which is involved in the degradation of L-serine and L-threonine to acetate and propionate, respectively. The tdc operon is comprised of one regulatory gene tdcA and six structural genes, tdcB to tdcG. The expression of the tdc operon is affected by several transcription factors including the cAMP receptor protein (CRP), integration host factor (IHF), histone-like protein (HU), and the operon specific regulators TdcA and TcdR. TcdR is divergently transcribed from the operon and encodes a small protein that is required for efficient expression of the Escherichia coli tdc operon. This substrate-binding domain shows significant homology to the type 2 periplasmic binding proteins (PBP2), which are responsible for the uptake of a variety of substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. The PBP2 bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis.
Pssm-ID: 176110 [Multi-domain] Cd Length: 201 Bit Score: 40.03 E-value: 6.37e-04
The C-terminal substrate binding domain of LysR-type transcriptional regulator metR, which ...
105-183
1.30e-03
The C-terminal substrate binding domain of LysR-type transcriptional regulator metR, which regulates the expression of methionine biosynthetic genes, contains type 2 periplasmic binding fold; MetR, a member of the LysR family, is a positive regulator for the metA, metE, metF, and metH genes. The sulfur-containing amino acid methionine is the universal initiator of protein synthesis in all known organisms and its derivative S-adenosylmethionine (SAM) and autoinducer-2 (AI-2) are involved in various cellular processes. SAM plays a central role as methyl donor in methylation reactions, which are essential for the biosynthesis of phospholipids, proteins, DNA and RNA. The interspecies signaling molecule AI-2 is involved in cell-cell communication process (quorum sensing) and gene regulation in bacteria. Although methionine biosynthetic enzymes and metabolic pathways are well conserved in bacteria, the regulation of methionine biosynthesis involves various regulatory mechanisms. In Escherichia coli and Salmonella enterica serovar Typhimurium, MetJ and MetR regulate the expression of methionine biosynthetic genes. The MetJ repressor negatively regulates the E. coli met genes, except for metH. Several of these genes are also under the positive control of MetR with homocysteine as a co-inducer. In Bacillus subtilis, the met genes are controlled by S-box termination-antitermination system. This substrate-binding domain shows significant homology to the type 2 periplasmic binding proteins (PBP2), which are responsible for the uptake of a variety of substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. The PBP2 bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis.
Pssm-ID: 176132 Cd Length: 198 Bit Score: 39.09 E-value: 1.30e-03
The C-terminal substrate binding domain of an uncharacterized LysR-type transcriptional ...
152-273
5.45e-03
The C-terminal substrate binding domain of an uncharacterized LysR-type transcriptional regulator CrgA-like, contains the type 2 periplasmic binding fold; This CD represents the substrate binding domain of an uncharacterized LysR-type transcriptional regulator (LTTR) CrgA-like 6. The LTTRs are acting as both auto-repressors and activators of target promoters, controlling operons involved in a wide variety of cellular processes such as amino acid biosynthesis, CO2 fixation, antibiotic resistance, degradation of aromatic compounds, nodule formation of nitrogen-fixing bacteria, and synthesis of virulence factors, to name a few. In contrast to the tetrameric form of other LTTRs, CrgA from Neisseria meningitides assembles into an octameric ring, which can bind up to four 63-bp DNA oligonucleotides. Phylogenetic cluster analysis showed that the CrgA-like regulators form a subclass of the LTTRs that function as octamers. The CrgA is an auto-repressor of its own gene and activates the expression of the mdaB gene which coding for an NADPH-quinone reductase and that its action is increased by MBL (alpha-methylene-gamma-butyrolactone), an inducer of NADPH-quinone oxidoreductase. The structural topology of this substrate-binding domain is most similar to that of the type 2 periplasmic binding proteins (PBP2), which are responsible for the uptake of a variety of substrates such as phosphate, sulfate, polysaccharides, lysine/arginine/ornithine, and histidine. The PBP2 bind their ligand in the cleft between these domains in a manner resembling a Venus flytrap. After binding their specific ligand with high affinity, they can interact with a cognate membrane transport complex comprised of two integral membrane domains and two cytoplasmically located ATPase domains. This interaction triggers the ligand translocation across the cytoplasmic membrane energized by ATP hydrolysis.
Pssm-ID: 176164 [Multi-domain] Cd Length: 199 Bit Score: 37.15 E-value: 5.45e-03
Database: CDSEARCH/cdd Low complexity filter: no Composition Based Adjustment: yes E-value threshold: 0.01
References:
Wang J et al. (2023), "The conserved domain database in 2023", Nucleic Acids Res.51(D)384-8.
Lu S et al. (2020), "The conserved domain database in 2020", Nucleic Acids Res.48(D)265-8.
Marchler-Bauer A et al. (2017), "CDD/SPARCLE: functional classification of proteins via subfamily domain architectures.", Nucleic Acids Res.45(D)200-3.
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