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Research in Microbiology Sep 2002Some bacteria lack sugar permeases of the bacterial phosphotransferase system (PTS) but encode within their genomes phosphoryl transfer proteins of the PTS that probably... (Review)
Review
Some bacteria lack sugar permeases of the bacterial phosphotransferase system (PTS) but encode within their genomes phosphoryl transfer proteins of the PTS that probably function in regulation. These proteins include homologues of HPr (PtsH), the ATP-dependent HPr(ser) kinase/phosphatase (PtsK) and the PEP-dependent HPr(his) kinase known as Enzyme I (PtsI). We identify all currently sequenced homologues of these proteins, multiply align their sequences and construct phylogenetic trees in order to derive functional, structural and evolutionary conclusions. We show that no bacterium possesses more than one HPr kinase and that these proteins are probably all orthologous. alpha-Proteobacteria possess truncated HPr kinases which probably serve a unified regulatory function together with other PTS proteins. The Enzymes I are orthologous in all Gram-positive bacteria and some Gram-negative bacteria, but other Gram-negative bacteria exhibit paralogues that fall into 5 functional types. No bacterium with a fully sequenced genome exhibits all of these types. With the exception of the classical Enzymes I, each of these functional types exhibits a distinctive set of accompanying domains, usually with a characteristic domain order. One functional type, the fructose-specific type, includes two phylogenetically different subgroups with different domain orders. The results establish that domain associations occurred early during evolutionary history of the PTS, and that subsequent domain rearrangements occurred rarely. Our findings define the evolutionary histories of these important bacterial proteins and provide guides for functional assignment of PTS-related proteins encoded by genes revealed by genome sequencing.
Topics: Amino Acid Sequence; Bacteria; Bacterial Proteins; Molecular Sequence Data; Phosphoenolpyruvate Sugar Phosphotransferase System; Phosphotransferases (Nitrogenous Group Acceptor); Phylogeny; Protein Serine-Threonine Kinases
PubMed: 12405346
DOI: 10.1016/s0923-2508(02)01339-6 -
Microbiology and Molecular Biology... Jun 2014The bacterial phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS) carries out both catalytic and regulatory functions. It catalyzes the transport and... (Review)
Review
The bacterial phosphoenolpyruvate:carbohydrate phosphotransferase system: regulation by protein phosphorylation and phosphorylation-dependent protein-protein interactions.
The bacterial phosphoenolpyruvate (PEP):carbohydrate phosphotransferase system (PTS) carries out both catalytic and regulatory functions. It catalyzes the transport and phosphorylation of a variety of sugars and sugar derivatives but also carries out numerous regulatory functions related to carbon, nitrogen, and phosphate metabolism, to chemotaxis, to potassium transport, and to the virulence of certain pathogens. For these different regulatory processes, the signal is provided by the phosphorylation state of the PTS components, which varies according to the availability of PTS substrates and the metabolic state of the cell. PEP acts as phosphoryl donor for enzyme I (EI), which, together with HPr and one of several EIIA and EIIB pairs, forms a phosphorylation cascade which allows phosphorylation of the cognate carbohydrate bound to the membrane-spanning EIIC. HPr of firmicutes and numerous proteobacteria is also phosphorylated in an ATP-dependent reaction catalyzed by the bifunctional HPr kinase/phosphorylase. PTS-mediated regulatory mechanisms are based either on direct phosphorylation of the target protein or on phosphorylation-dependent interactions. For regulation by PTS-mediated phosphorylation, the target proteins either acquired a PTS domain by fusing it to their N or C termini or integrated a specific, conserved PTS regulation domain (PRD) or, alternatively, developed their own specific sites for PTS-mediated phosphorylation. Protein-protein interactions can occur with either phosphorylated or unphosphorylated PTS components and can either stimulate or inhibit the function of the target proteins. This large variety of signal transduction mechanisms allows the PTS to regulate numerous proteins and to form a vast regulatory network responding to the phosphorylation state of various PTS components.
Topics: Bacteria; Bacterial Proteins; Biological Transport; Carbohydrate Metabolism; Phosphoenolpyruvate; Phosphorylation; Phosphotransferases; Protein Binding
PubMed: 24847021
DOI: 10.1128/MMBR.00001-14 -
Advances in Biological Regulation Jan 2019The protein kinase family is characterized by substantial conservation of architectural elements that are required for both ATP binding and phosphotransferase activity.... (Review)
Review
The protein kinase family is characterized by substantial conservation of architectural elements that are required for both ATP binding and phosphotransferase activity. Many of these structural features have also been identified in homologous enzymes that phosphorylate a variety of alternative, non-protein substrates. A comparative structural analysis of these different kinase sub-classes is a portal to a greater understanding of reaction mechanisms, enzyme regulation, inhibitor-development strategies, and superfamily-level evolutionary relationships. To serve such advances, we review structural elements of the protein kinase fold that are conserved in the subfamily of inositol phosphate kinases (InsPKs) that share a PxxxDxKxG catalytic signature: inositol 1,4,5-trisphosphate kinase (IP3K), inositol hexakisphosphate kinase (IP6K), and inositol polyphosphate multikinase (IPMK). We describe conservation of the fundamental two-lobe kinase architecture: an N-lobe constructed upon an anti-parallel β-strand scaffold, which is coupled to a largely helical C-lobe by a single, adenine-binding hinge. This equivalency also includes a G-loop that embraces the β/γ-phosphates of ATP, a transition-state stabilizing residue (Lys/His), and a Mg-positioning aspartate residue within a catalytic triad. Furthermore, we expand this list of conserved structural features to include some not previously identified in InsPKs: a 'gatekeeper' residue in the N-lobe, and an 'αF'-like helix in the C-lobe that anchors two structurally-stabilizing, hydrophobic spines, formed from non-consecutive residues that span the two lobes. We describe how this wide-ranging structural homology can be exploited to develop lead inhibitors of IP6K and IPMK, by using strategies similar to those that have generated ATP-competing inhibitors of protein-kinases. We provide several examples to illustrate how such an approach could benefit human health.
Topics: Animals; Binding Sites; Humans; Inositol Phosphates; Phosphorylation; Phosphotransferases (Alcohol Group Acceptor); Phosphotransferases (Phosphate Group Acceptor); Protein Kinases; Protein Structure, Secondary
PubMed: 30392847
DOI: 10.1016/j.jbior.2018.10.006 -
Functional characterization of the phosphotransferase system in Parageobacillus thermoglucosidasius.Scientific Reports May 2023Parageobacillus thermoglucosidasius is a thermophilic bacterium characterized by rapid growth, low nutrient requirements, and amenability to genetic manipulation. These...
Parageobacillus thermoglucosidasius is a thermophilic bacterium characterized by rapid growth, low nutrient requirements, and amenability to genetic manipulation. These characteristics along with its ability to ferment a broad range of carbohydrates make P. thermoglucosidasius a potential workhorse in whole-cell biocatalysis. The phosphoenolpyruvate:carbohydrate phosphotransferase system (PTS) catalyzes the transport and phosphorylation of carbohydrates and sugar derivatives in bacteria, making it important for their physiological characterization. In this study, the role of PTS elements on the catabolism of PTS and non-PTS substrates was investigated for P. thermoglucosidasius DSM 2542. Knockout of the common enzyme I, part of all PTSs, showed that arbutin, cellobiose, fructose, glucose, glycerol, mannitol, mannose, N-acetylglucosamine, N-acetylmuramic acid, sorbitol, salicin, sucrose, and trehalose were PTS-dependent on translocation and coupled to phosphorylation. The role of each putative PTS was investigated and six PTS-deletion variants could not grow on arbutin, mannitol, N-acetylglucosamine, sorbitol, and trehalose as the main carbon source, or showed diminished growth on N-acetylmuramic acid. We concluded that PTS is a pivotal factor in the sugar metabolism of P. thermoglucosidasius and established six PTS variants important for the translocation of specific carbohydrates. This study lays the groundwork for engineering efforts with P. thermoglucosidasius towards efficient utilization of diverse carbon substrates for whole-cell biocatalysis.
Topics: Acetylglucosamine; Arbutin; Trehalose; Phosphotransferases; Carbohydrates; Bacteria; Mannitol; Sorbitol; Phosphoenolpyruvate Sugar Phosphotransferase System; Bacterial Proteins
PubMed: 37130962
DOI: 10.1038/s41598-023-33918-1 -
Biomedicine & Pharmacotherapy =... Jan 2024Polycystic ovary syndrome (PCOS) is a highly prevalent endocrine and metabolic disorder that is closely associated with the proliferation and apoptosis of ovarian...
Polycystic ovary syndrome (PCOS) is a highly prevalent endocrine and metabolic disorder that is closely associated with the proliferation and apoptosis of ovarian granulosa cells (GCs). Ampelopsis japonica (AJ) is the dried tuberous root of Ampelopsis japonica (Thunb.) Makino (A. japonica), with anti-inflammatory, antioxidant, antibacterial, antiviral, wound-healing, and antitumor properties; however, it is unclear whether this herb has a therapeutic effect on PCOS. Therefore, this study aimed to investigate the pharmacological effect of AJ on PCOS and reveal its potential mechanism of action. A PCOS rat model was established using letrozole. After establishing the PCOS model, the rats received oral treatment of AJ and Diane-35 (Positive drug: ethinylestradiol + cyproterone tablets) for 2 weeks. Lipidomics was conducted using liquid-phase mass spectrometry and chromatography. AJ significantly regulated serum hormone levels and attenuated pathological variants in the ovaries of rats with PCOS. Furthermore, AJ significantly reduced the apoptotic rate of ovarian GCs. Lipidomic analysis revealed that AJ modulated glycerolipid and glycerophospholipid metabolic pathways mediated by lipoprotein lipase (Lpl), diacylglycerol choline phosphotransferase (Chpt1), and choline/ethanolamine phosphotransferase (Cept1). Therefore, we established that AJ may reduce ovarian GC apoptosis by modulating lipid metabolism, ultimately improving ovulatory dysfunction in PCOS. Therefore, AJ is a novel candidate for PCOS treatment.
Topics: Female; Humans; Rats; Animals; Polycystic Ovary Syndrome; Ampelopsis; Lipid Metabolism; Phosphotransferases; Choline
PubMed: 38159378
DOI: 10.1016/j.biopha.2023.116093 -
MBio Jun 2022The rhizobium-legume symbiosis is essential for sustainable agriculture by reducing nitrogen fertilizer input, but its efficiency varies under fluctuating soil...
The rhizobium-legume symbiosis is essential for sustainable agriculture by reducing nitrogen fertilizer input, but its efficiency varies under fluctuating soil conditions and resources. The nitrogen-related phosphotransferase system (PTS) consisting of PtsP, PtsO, and PtsN is required for optimal nodulation and nitrogen fixation efficiency of the broad-host-range Sinorhizobium fredii CCBAU45436 associated with diverse legumes, though the underlying mechanisms remain elusive. This work characterizes the PtsN-KdpDE-KdpFABC pathway that contributes to low potassium adaptation and competitive nodulation of CCBAU45436. Among three PtsN, PtsN is the major functional homolog. The unphosphorylated PtsN binds the sensory kinase KdpD through a non-canonical interaction with the GAF domain of KdpD, while the region covering HisKA-HATPase domains mediates the interaction of KdpD with the response regulator KdpE. KdpE directly activates the operon encoding the conserved high-affinity potassium uptake system. Disruption of this signaling pathway leads to reduced nodule number, nodule occupancy, and low potassium adaptation ability, but without notable effects on rhizoplane colonization. The induction of key nodulation genes and in host roots during early symbiotic interactions is impaired when inoculating the mutant that shows delayed nodulation. The nodulation defect of the mutant can be rescued by supplying replete potassium. Potassium is actively consumed by both prokaryotes and eukaryotes, and components of the PTS-KdpDE-KdpFABC pathway are widely conserved in bacteria, highlighting the global importance of this pathway in bacteria-host interactions. In all ecological niches, potassium is actively consumed by diverse prokaryotes and their interacting eukaryote hosts. It is only just emerging that potassium is a key player in host-pathogen interactions, and the role of potassium in mutualistic interactions remains largely unknown. This work is focused on the mutualistic symbiosis between rhizobia and legumes. We report that the nitrogen-related phosphotransferase system PTS, the two-component system KdpDE, and the high-affinity potassium uptake system KdpFABC constitute a pathway that is important for low potassium adaptation and optimal nodulation of rhizobia. Given the widely conserved PTS, KdpDE, and KdpFABC in bacteria and increasing knowledge on microbiome for various niches, the PTS-KdpDE-KdpFABC pathway can be globally important in the biosphere.
Topics: Gene Expression Regulation, Bacterial; Nitrogen; Phosphoenolpyruvate Sugar Phosphotransferase System; Phosphorylation; Phosphotransferases; Potassium; Rhizobium; Sinorhizobium fredii; Symbiosis
PubMed: 35491828
DOI: 10.1128/mbio.03721-21 -
Journal of Bacteriology Oct 1977d-Arabitol was observed to be toxic to many laboratory strains of Escherichia coli K-12, and xylitol was found to be toxic to an existing E. coli C mutant strain....
d-Arabitol was observed to be toxic to many laboratory strains of Escherichia coli K-12, and xylitol was found to be toxic to an existing E. coli C mutant strain. Fructose-specific components of the phosphoenolpyruvate:sugar phosphotransferase system are required for xylitol toxicity. Selection for xylitol resistance results in Fru(-) strains blocked in fructose phosphotransferase. Introduction of the ptsF or ptsI mutation into a xylitol-sensitive strain eliminates sensitivity. [(14)C]fructose uptake experiments imply that the mutation to xylitol sensitivity, which is co-transducible with ara and leu, results in derepression of normally inducible fructose phosphotransferase. Wild-type strains also become xylitol sensitive if induced by (and then removed from) fructose. Xylitol toxicity is prevented by fructose in both wild-type and mutant strains. Circumstances causing xylitol, a new food additive, to become toxic to an otherwise insensitive wild-type organism have not been reported previously. The d-arabitol-sensitive laboratory strains are galactitol (dulcitol) utilizers, although most other strains are not. Selection for d-arabitol resistance results in Gat(-) strains blocked in a constitutive galactitol-specific component of the phosphotransferase system. A mutation causing d-arabitol sensitivity occurred many years ago in AB284, the parent of AB311, AB312, AB313, and many other strains. d-Arabitol sensitivity also occurs in sorbitol-constitutive strains and is shown, like the previous two instances of pentitol toxicities, to result from a constitutive phosphotransferase, which is blocked in mutants selected for resistance.
Topics: Arabinose; Enzyme Repression; Escherichia coli; Fructose; Galactitol; Genes; Mutation; Phenotype; Phosphotransferases; Sorbitol; Sugar Alcohols; Xylitol
PubMed: 334721
DOI: 10.1128/jb.132.1.166-173.1977 -
Proceedings of the National Academy of... Apr 2016Rifampin (RIF) is a first-line drug used for the treatment of tuberculosis and other bacterial infections. Various RIF resistance mechanisms have been reported, and...
Rifampin (RIF) is a first-line drug used for the treatment of tuberculosis and other bacterial infections. Various RIF resistance mechanisms have been reported, and recently an RIF-inactivation enzyme, RIF phosphotransferase (RPH), was reported to phosphorylate RIF at its C21 hydroxyl at the cost of ATP. However, the underlying molecular mechanism remained unknown. Here, we solve the structures of RPH from Listeria monocytogenes (LmRPH) in different conformations. LmRPH comprises three domains: an ATP-binding domain (AD), an RIF-binding domain (RD), and a catalytic His-containing domain (HD). Structural analyses reveal that the C-terminal HD can swing between the AD and RD, like a toggle switch, to transfer phosphate. In addition to its catalytic role, the HD can bind to the AD and induce conformational changes that stabilize ATP binding, and the binding of the HD to the RD is required for the formation of the RIF-binding pocket. A line of hydrophobic residues forms the RIF-binding pocket and interacts with the 1-amino, 2-naphthol, 4-sulfonic acid and naphthol moieties of RIF. The R group of RIF points toward the outside of the pocket, explaining the low substrate selectivity of RPH. Four residues near the C21 hydroxyl of RIF, His825, Arg666, Lys670, and Gln337, were found to play essential roles in the phosphorylation of RIF; among these the His825 residue may function as the phosphate acceptor and donor. Our study reveals the molecular mechanism of RIF phosphorylation catalyzed by RPH and will guide the development of a new generation of rifamycins.
Topics: Adenosine Triphosphate; Binding Sites; Catalytic Domain; Crystallography, X-Ray; Drug Resistance, Bacterial; Listeria monocytogenes; Microbial Sensitivity Tests; Naphthols; Phosphotransferases; Protein Binding; Protein Structure, Tertiary; Rifampin; Sulfonic Acids
PubMed: 27001859
DOI: 10.1073/pnas.1523614113 -
World Journal of Microbiology &... Feb 2016The acetone-butanol-ethanol fermentation of solventogenic clostridia was operated as a successful, worldwide industrial process during the first half of the twentieth...
The acetone-butanol-ethanol fermentation of solventogenic clostridia was operated as a successful, worldwide industrial process during the first half of the twentieth century, but went into decline for economic reasons. The recent resurgence in interest in the fermentation has been due principally to the recognised potential of butanol as a biofuel, and development of reliable molecular tools has encouraged realistic prospects of bacterial strains being engineered to optimise fermentation performance. In order to minimise costs, emphasis is being placed on waste feedstock streams containing a range of fermentable carbohydrates. It is therefore important to develop a detailed understanding of the mechanisms of carbohydrate uptake so that effective engineering strategies can be identified. This review surveys present knowledge of sugar uptake and its control in solventogenic clostridia. The major mechanism of sugar uptake is the PEP-dependent phosphotransferase system (PTS), which both transports and phosphorylates its sugar substrates and plays a central role in metabolic regulation. Clostridial genome sequences have indicated the presence of numerous phosphotransferase systems for uptake of hexose sugars, hexose derivatives and disaccharides. On the other hand, uptake of sugars such as pentoses occurs via non-PTS mechanisms. Progress in characterization of clostridial sugar transporters and manipulation of control mechanisms to optimise sugar fermentation is described.
Topics: Base Sequence; Biofuels; Carbohydrate Metabolism; Catabolite Repression; Clostridium; Ethanol; Fermentation; Phosphotransferases
PubMed: 26748809
DOI: 10.1007/s11274-015-1981-4 -
Journal of Molecular Microbiology and... 2015In 1964, Kundig, Ghosh and Roseman reported the discovery of the phosphoenolpyruvate:sugar phosphotransferase system (PTS), which they subsequently proposed might...
In 1964, Kundig, Ghosh and Roseman reported the discovery of the phosphoenolpyruvate:sugar phosphotransferase system (PTS), which they subsequently proposed might catalyze sugar transport as well as sugar phosphorylation. What we have learned in the 50 years since its discovery is that, in addition to these primary functions, the PTS serves as a complex protein kinase system that regulates a wide variety of transport, metabolic and mutagenic processes as well as the expression of numerous genes. Recent operon- and genome-sequencing projects have revealed novel PTS protein-encoding genes, many of which have yet to be functionally defined. The current picture of the PTS is that of a complex system with ramifications in all aspects of cellular physiology. Moreover, its mosaic evolutionary history is unusual and intriguing. The PTS can be considered to serve many prokaryotes in capacities of communication and coordination, as do the nervous systems of animals.
Topics: Bacteria; Escherichia coli; Gene Expression Regulation, Bacterial; Genes, Bacterial; Multigene Family; Operon; Phosphoenolpyruvate Sugar Phosphotransferase System; Phosphorylation; Phosphotransferases
PubMed: 26159069
DOI: 10.1159/000381215