-
European Journal of Medicinal Chemistry Aug 2017The dominant paradigm in drug discovery is to design ligands with maximum selectivity to act on individual drug targets. With the target-based approach, many new... (Review)
Review
The dominant paradigm in drug discovery is to design ligands with maximum selectivity to act on individual drug targets. With the target-based approach, many new chemical entities have been discovered, developed, and further approved as drugs. However, there are a large number of complex diseases such as cancer that cannot be effectively treated or cured only with one medicine to modulate the biological function of a single target. As simultaneous intervention of two (or multiple) cancer progression relevant targets has shown improved therapeutic efficacy, the innovation of multi-targeted drugs has become a promising and prevailing research topic and numerous multi-targeted anticancer agents are currently at various developmental stages. However, most multi-pharmacophore scaffolds are usually discovered by serendipity or screening, while rational design by combining existing pharmacophore scaffolds remains an enormous challenge. In this review, four types of multi-pharmacophore modes are discussed, and the examples from literature will be used to introduce attractive lead compounds with the capability of simultaneously interfering with different enzyme or signaling pathway of cancer progression, which will reveal the trends and insights to help the design of the next generation multi-targeted anticancer agents.
Topics: Animals; Antineoplastic Agents; Cell Proliferation; Dose-Response Relationship, Drug; Drug Design; Drug Discovery; Humans; Molecular Structure; Phosphotransferases; Protein Kinase Inhibitors; Structure-Activity Relationship
PubMed: 28494256
DOI: 10.1016/j.ejmech.2017.05.016 -
Gut Microbes Dec 2023In many species, virulence is regulated by quorum sensing, which is regulated by a complex, multichannel, two-component phosphorelay circuit. Through this circuit,...
In many species, virulence is regulated by quorum sensing, which is regulated by a complex, multichannel, two-component phosphorelay circuit. Through this circuit, sensor kinases transmit sensory information to the phosphotransferase LuxU via a phosphotransfer mechanism, which in turn transmits the signal to the response regulator LuxO. For , type III secretion system 1 (T3SS1) is required for cytotoxicity, but it is unclear how quorum sensing regulates T3SS1 expression. Herein, we report that a hybrid histidine kinase, ArcB, instead of LuxU, and sensor kinase LuxQ and response regulator LuxO, collectively orchestrate T3SS1 expression in . Under high oxygen conditions, LuxQ can interact with ArcB directly and phosphorylates the Hpt domain of ArcB. The Hpt domain of ArcB phosphorylates the downstream response regulator LuxO instead of ArcA. LuxO then activates transcription of the T3SS1 gene cluster. Under hypoxic conditions, ArcB autophosphorylates and phosphorylates ArcA, whereas ArcA does not participate in regulating the expression of T3SS1. Our data provides evidence of an alternative regulatory path involving the quorum sensing phosphorelay and adds another layer of understanding about the environmental regulation of gene expression in .
Topics: Vibrio parahaemolyticus; Quorum Sensing; Type III Secretion Systems; Bacterial Proteins; Gastrointestinal Microbiome; Phosphotransferases; Gene Expression Regulation, Bacterial
PubMed: 37982663
DOI: 10.1080/19490976.2023.2281016 -
Biological Chemistry Jun 2018Mutations in human leucine-rich-repeat kinase 2 (LRRK2) have been found to be the most frequent cause of late-onset Parkinson's Disease (PD). LRRK2 is a large protein... (Review)
Review
Mutations in human leucine-rich-repeat kinase 2 (LRRK2) have been found to be the most frequent cause of late-onset Parkinson's Disease (PD). LRRK2 is a large protein with two enzymatic domains, a GTPase and a kinase domain. A cluster of (auto)-phosphorylation sites within the N-terminus of LRRK2 have been shown to be crucial for the localization of LRRK2 and is important for PD pathogenesis. In addition, phosphorylation of sites within the G-domain of the protein affect GTPase activity. Here we discuss the role of these (auto)-phosphorylation sites of LRRK2 and their regulation by phosphatases and upstream kinases.
Topics: Humans; Leucine-Rich Repeat Serine-Threonine Protein Kinase-2; Phosphoric Monoester Hydrolases; Phosphorylation; Phosphotransferases
PubMed: 29537215
DOI: 10.1515/hsz-2017-0332 -
Life Sciences Dec 2016Phosphatidylinositol-4,5-bisphosphate 3-kinases (PI3Ks) are regulatory enzymes involved in the generation of lipid species that modulate cellular signaling pathways... (Review)
Review
Phosphatidylinositol-4,5-bisphosphate 3-kinases (PI3Ks) are regulatory enzymes involved in the generation of lipid species that modulate cellular signaling pathways through downstream effectors to influence a variety of cellular functions. Years of intensive study of PI3Ks have produced a significant body of literature in many areas, including that PI3K can mediate intracellular vesicular trafficking and through these actions contribute to a number of important physiological functions. This review focuses on the crucial roles that PI3K and AKT, a major downstream partner of PI3K, play in the regulation of vesicle trafficking during various forms of vesicular endocytosis and exocytosis.
Topics: Animals; Endocytosis; Exocytosis; Humans; Phosphatidylinositol 3-Kinases; Phosphotransferases (Alcohol Group Acceptor); Proto-Oncogene Proteins c-akt; Signal Transduction
PubMed: 27760304
DOI: 10.1016/j.lfs.2016.10.018 -
Current Topics in Medicinal Chemistry 2020
Topics: Humans; Phosphotransferases; Protein Kinase Inhibitors; Small Molecule Libraries
PubMed: 32830621
DOI: 10.2174/156802662017200624114631 -
MSphere Jan 2020Prebiotic oligosaccharides, such as fructooligosaccharides, are increasingly being used to modulate the composition and activity of the gut microbiota. However,...
Prebiotic oligosaccharides, such as fructooligosaccharides, are increasingly being used to modulate the composition and activity of the gut microbiota. However, carbohydrate utilization analyses and metagenomic studies recently revealed the ability of deleterious and uncultured human gut bacterial species to metabolize these functional foods. Moreover, because of the difficulties of functionally profiling transmembrane proteins, only a few prebiotic transporters have been biochemically characterized to date, while carbohydrate binding and transport are the first and thus crucial steps in their metabolization. Here, we describe the molecular mechanism of a phosphotransferase system, highlighted as a dietary and pathology biomarker in the human gut microbiome. This transporter is encoded by a metagenomic locus that is highly conserved in several human gut , including species. We developed a generic strategy to deeply analyze, and , the specificity and functionality of recombinant transporters in , combining carbohydrate utilization locus and host genome engineering and quantification of the binding, transport, and growth rates with analysis of phosphorylated carbohydrates by mass spectrometry. We demonstrated that the fructooligosaccharide transporter is specific for kestose, whether for binding, transport, or phosphorylation. This constitutes the biochemical proof of effective phosphorylation of glycosides with a degree of polymerization of more than 2, extending the known functional diversity of phosphotransferase systems. Based on these new findings, we revisited the classification of these carbohydrate transporters. Prebiotics are increasingly used as food supplements, especially in infant formulas, to modify the functioning and composition of the microbiota. However, little is currently known about the mechanisms of prebiotic recognition and transport by gut bacteria, while these steps are crucial in their metabolism. In this study, we established a new strategy to profile the specificity of oligosaccharide transporters, combining microbiomics, genetic locus and strain engineering, and state-of-the art metabolomics. We revisited the transporter classification database and proposed a new way to classify these membrane proteins based on their structural and mechanistic similarities. Based on these developments, we identified and characterized, at the molecular level, a fructooligosaccharide transporting phosphotransferase system, which constitutes a biomarker of diet and gut pathology. The deciphering of this prebiotic metabolization mechanism by a nonbeneficial bacterium highlights the controversial use of prebiotics, especially in the context of chronic gut diseases.
Topics: Bacteria; Carbohydrate Metabolism; Escherichia coli; Fermentation; Gastrointestinal Microbiome; Humans; Metabolomics; Oligosaccharides; Phosphotransferases; Prebiotics
PubMed: 31915220
DOI: 10.1128/mSphere.00771-19 -
European Journal of Medicinal Chemistry Mar 2021Sphingosine kinases (SphKs) are lipid kinases that catalyze the phosphorylation of sphingosine (Sph) to sphingosine-1-phosphate (S1P). As a bioactive lipid, S1P plays a... (Review)
Review
Sphingosine kinases (SphKs) are lipid kinases that catalyze the phosphorylation of sphingosine (Sph) to sphingosine-1-phosphate (S1P). As a bioactive lipid, S1P plays a role outside and inside the cell to regulate biological processes. The overexpression of SphKs is related to a variety of pathophysiological conditions. Targeting the S1P signaling pathway is a potential treatment strategy for many diseases. SphKs are key kinases of the S1P signaling pathway. The SphK family includes two isoforms: SphK1 and SphK2. Determination of the co-crystal structure of SphK1 with various inhibitors has laid a solid foundation for the development of small molecule inhibitors targeting SphKs. This paper reviews the differences and connections between the two isoforms and the structure of SphK1 crystals, especially the structure of its Sph "J-shaped" channel binding site. This review also summarizes the recent development of SphK1 and SphK2 selective inhibitors and the exploration of the unresolved SphK2 structure.
Topics: Animals; Computer-Aided Design; Crystallography, X-Ray; Drug Design; Enzyme Inhibitors; Humans; Models, Molecular; Molecular Structure; Phosphotransferases (Alcohol Group Acceptor)
PubMed: 33454547
DOI: 10.1016/j.ejmech.2021.113164 -
ACS Chemical Biology Jan 2022Capreomycin (CMN) is an important second-line antituberculosis antibiotic isolated from subspecies . The gene cluster for CMN biosynthesis has been identified and...
Capreomycin (CMN) is an important second-line antituberculosis antibiotic isolated from subspecies . The gene cluster for CMN biosynthesis has been identified and sequenced, wherein the gene was annotated as a phosphotransferase likely engaging in self-resistance. Previous studies reported that Cph inactivates two CMNs, CMN IA and IIA, by phosphorylation. We, herein, report that (1) harboring the gene becomes resistant to both CMN IIA and IIB, (2) phylogenetic analysis regroups Cph to a new clade in the phosphotransferase protein family, (3) Cph shares a three-dimensional structure akin to the aminoglycoside phosphotransferases with a high binding affinity () to both CMN IIA and IIB at micromolar levels, and (4) Cph utilizes either ATP or GTP as a phosphate group donor transferring its γ-phosphate to the hydroxyl group of CMN IIA. Until now, Cph and Vph (viomycin phosphotransferase) are the only two known enzymes inactivating peptide-based antibiotics through phosphorylation. Our biochemical characterization and structural determination conclude that Cph confers the gene-carrying species resistance to CMN by means of either chemical modification or physical sequestration, a naturally manifested belt and braces strategy. These findings add a new chapter into the self-resistance of bioactive natural products, which is often overlooked while designing new bioactive molecules.
Topics: Actinobacteria; Antibiotics, Antitubercular; Bacterial Proteins; Capreomycin; Gene Expression Regulation, Bacterial; Gene Expression Regulation, Enzymologic; Models, Molecular; Molecular Structure; Phosphotransferases (Alcohol Group Acceptor); Phylogeny; Protein Conformation
PubMed: 34994196
DOI: 10.1021/acschembio.1c00799 -
Biochemistry Jan 2015
Topics: A Kinase Anchor Proteins; Animals; Cyclic AMP-Dependent Protein Kinases; Humans; MAP Kinase Signaling System; Phosphotransferases
PubMed: 25517407
DOI: 10.1021/bi501533e -
Journal of Bacteriology Apr 2022Streptococcus mutans is a major pathobiont involved in the development of dental caries. Its ability to utilize numerous sugars and to effectively respond to...
Streptococcus mutans is a major pathobiont involved in the development of dental caries. Its ability to utilize numerous sugars and to effectively respond to environmental stress promotes S. mutans proliferation in oral biofilms. Because of their quick action and low energetic cost, noncoding small RNAs (sRNAs) represent an ideal mode of gene regulation in stress response networks, yet their roles in oral pathogens have remained largely unexplored. We identified 15 novel sRNAs in S. mutans and show that they respond to four stress-inducing conditions commonly encountered by the pathogen in human mouth: sugar-phosphate stress, hydrogen peroxide exposure, high temperature, and low pH. To better understand the role of sRNAs in S. mutans, we further explored the function of the novel sRNA SmsR4. Our data demonstrate that SmsR4 regulates the enzyme IIA (EIIA) component of the sorbitol phosphotransferase system, which transports and phosphorylates the sugar alcohol sorbitol. The fine-tuning of EIIA availability by SmsR4 likely promotes S. mutans growth while using sorbitol as the main carbon source. Our work lays a foundation for understanding the role of sRNAs in regulating gene expression in stress response networks in S. mutans and highlights the importance of the underexplored phenomenon of posttranscriptional gene regulation in oral bacteria. Small RNAs (sRNAs) are important gene regulators in bacteria, but the identities and functions of sRNAs in Streptococcus mutans, the principal bacterium involved in the formation of dental caries, are unknown. In this study, we identified 15 putative sRNAs in S. mutans and show that they respond to four common stress-inducing conditions present in human mouth: sugar-phosphate stress, hydrogen peroxide exposure, high temperature, and low pH. We further show that the novel sRNA SmsR4 likely modulates sorbitol transport into the cell by regulating SMU_313 mRNA, which encodes the EIIA subunit of the sorbitol phosphotransferase system. Gaining a better understanding of sRNA-based gene regulation may provide new opportunities to develop specific inhibitors of S. mutans growth, thereby improving oral health.
Topics: Dental Caries; Gene Expression Regulation, Bacterial; Humans; Hydrogen Peroxide; Phosphates; Phosphotransferases; RNA, Small Untranslated; Sorbitol; Streptococcus mutans; Sugars
PubMed: 35285723
DOI: 10.1128/jb.00577-21