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Escudeiro P, Henry CS, Dias RP. Functional characterization of prokaryotic dark matter: the road so far and what lies ahead. CURRENT RESEARCH IN MICROBIAL SCIENCES 2022; 3:100159. [PMID: 36561390 PMCID: PMC9764257 DOI: 10.1016/j.crmicr.2022.100159] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/11/2022] [Revised: 07/18/2022] [Accepted: 08/05/2022] [Indexed: 12/25/2022] Open
Abstract
Eight-hundred thousand to one trillion prokaryotic species may inhabit our planet. Yet, fewer than two-hundred thousand prokaryotic species have been described. This uncharted fraction of microbial diversity, and its undisclosed coding potential, is known as the "microbial dark matter" (MDM). Next-generation sequencing has allowed to collect a massive amount of genome sequence data, leading to unprecedented advances in the field of genomics. Still, harnessing new functional information from the genomes of uncultured prokaryotes is often limited by standard classification methods. These methods often rely on sequence similarity searches against reference genomes from cultured species. This hinders the discovery of unique genetic elements that are missing from the cultivated realm. It also contributes to the accumulation of prokaryotic gene products of unknown function among public sequence data repositories, highlighting the need for new approaches for sequencing data analysis and classification. Increasing evidence indicates that these proteins of unknown function might be a treasure trove of biotechnological potential. Here, we outline the challenges, opportunities, and the potential hidden within the functional dark matter (FDM) of prokaryotes. We also discuss the pitfalls surrounding molecular and computational approaches currently used to probe these uncharted waters, and discuss future opportunities for research and applications.
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Affiliation(s)
- Pedro Escudeiro
- BioISI - Instituto de Biosistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal
| | - Christopher S. Henry
- Argonne National Laboratory, Lemont, Illinois, USA,University of Chicago, Chicago, Illinois, USA
| | - Ricardo P.M. Dias
- BioISI - Instituto de Biosistemas e Ciências Integrativas, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal,iXLab - Innovation for National Biological Resilience, Faculdade de Ciências, Universidade de Lisboa, Lisboa 1749-016, Portugal,Corresponding author.
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2
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Abstract
Analysis of the genes retained in the minimized Mycoplasma JCVI-Syn3A genome established that systems that repair or preempt metabolite damage are essential to life. Several genes known to have such functions were identified and experimentally validated, including 5-formyltetrahydrofolate cycloligase, coenzyme A (CoA) disulfide reductase, and certain hydrolases. Furthermore, we discovered that an enigmatic YqeK hydrolase domain fused to NadD has a novel proofreading function in NAD synthesis and could double as a MutT-like sanitizing enzyme for the nucleotide pool. Finally, we combined metabolomics and cheminformatics approaches to extend the core metabolic map of JCVI-Syn3A to include promiscuous enzymatic reactions and spontaneous side reactions. This extension revealed that several key metabolite damage control systems remain to be identified in JCVI-Syn3A, such as that for methylglyoxal.
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3
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Kölker S, Gleich F, Mütze U, Opladen T. Rare Disease Registries Are Key to Evidence-Based Personalized Medicine: Highlighting the European Experience. Front Endocrinol (Lausanne) 2022; 13:832063. [PMID: 35317224 PMCID: PMC8934440 DOI: 10.3389/fendo.2022.832063] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Received: 12/09/2021] [Accepted: 01/31/2022] [Indexed: 12/24/2022] Open
Abstract
Rare diseases, such as inherited metabolic diseases, have been identified as a health priority within the European Union more than 20 years ago and have become an integral part of EU health programs and European Reference Networks. Having the potential to pool data, to achieve sufficient sample size, to overcome the knowledge gap on rare diseases and to foster epidemiological and clinical research, patient registries are recognized as key instruments to evidence-based medicine for individuals with rare diseases. Patient registries can be used for multiple purposes, such as (1) describing the natural history and phenotypic diversity of rare diseases, (2) improving case definition and indication to treat, (3) identifying strategies for risk stratification and early prediction of disease severity (4), evaluating the impact of preventive, diagnostic, and therapeutic strategies on individual health, health economics, and the society, and (5) informing guideline development and policy makers. In contrast to clinical trials, patient registries aim to gather real-world evidence and to achieve generalizable results based on patient cohorts with a broad phenotypic spectrum. In order to develop a consistent and sustained framework for rare disease registries, uniform core principles have been formulated and have been formalized through the European Rare Disease Registration Infrastructure. Adherence to these core principles and compliance with the European general data protection regulations ensures that data collected and stored in patient registries can be exchanged and pooled in a protected environment. To illustrate the benefits and limitations of patient registries on rare disease research this review focuses on inherited metabolic diseases.
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4
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Scherpenzeel M, Conte F, Büll C, Ashikov A, Hermans E, Willems A, Tol W, Kragt E, Noga M, Moret EE, Heise T, Langereis JD, Rossing E, Zimmermann M, Rubio-Gozalbo ME, de Jonge MI, Adema GJ, Zamboni N, Boltje T, Lefeber DJ. Dynamic tracing of sugar metabolism reveals the mechanisms of action of synthetic sugar analogs. Glycobiology 2021; 32:239-250. [PMID: 34939087 PMCID: PMC8966471 DOI: 10.1093/glycob/cwab106] [Citation(s) in RCA: 13] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/23/2021] [Revised: 09/24/2021] [Accepted: 10/06/2021] [Indexed: 11/14/2022] Open
Abstract
Synthetic sugar analogs are widely applied in metabolic oligosaccharide engineering (MOE) and as novel drugs to interfere with glycoconjugate biosynthesis. However, mechanistic insights on their exact cellular metabolism over time are mostly lacking. We combined ion-pair ultrahigh performance liquid chromatography–triple quadrupole mass spectrometry mass spectrometry using tributyl- and triethylamine buffers for sensitive analysis of sugar metabolites in cells and organisms and identified low abundant nucleotide sugars, such as UDP-arabinose in human cell lines and CMP-sialic acid (CMP-NeuNAc) in Drosophila. Furthermore, MOE revealed that propargyloxycarbonyl (Poc)-labeled ManNPoc was metabolized to both CMP-NeuNPoc and UDP-GlcNPoc. Finally, time-course analysis of the effect of antitumor compound 3Fax-NeuNAc by incubation of B16-F10 melanoma cells with N-acetyl-D-[UL-13C6]glucosamine revealed full depletion of endogenous ManNAc 6-phosphate and CMP-NeuNAc within 24 h. Thus, dynamic tracing of sugar metabolic pathways provides a general approach to reveal time-dependent insights into the metabolism of synthetic sugars, which is important for the rational design of analogs with optimized effects.
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Affiliation(s)
- Monique Scherpenzeel
- Translational Metabolic Laboratory, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.,GlycoMScan B.V., Kloosterstraat 9, RE0329, 5349 AB Oss, The Netherlands
| | - Federica Conte
- Translational Metabolic Laboratory, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.,Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Christian Büll
- Department of Radiation Oncology, Radiotherapy & OncoImmunology Laboratory, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 32, Nijmegen, The Netherlands
| | - Angel Ashikov
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Esther Hermans
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Anke Willems
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Walinka Tol
- Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Else Kragt
- Translational Metabolic Laboratory, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Marek Noga
- Translational Metabolic Laboratory, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Ed E Moret
- Department of Chemical Biology & Drug Discovery, Utrecht Institute for Pharmaceutical Sciences, Utrecht University, Universiteitsweg 99, 3584 CG Utrecht, The Netherlands
| | - Torben Heise
- Cluster for Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, Nijmegen, The Netherlands
| | - Jeroen D Langereis
- Radboud Center for Infectious Diseases, Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Emiel Rossing
- Cluster for Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, Nijmegen, The Netherlands
| | | | - M Estela Rubio-Gozalbo
- Department of Clinical Genetics, department of Pediatrics, Maastricht University Medical Centre, Universiteitssingel 50, P.O. Box 616, box 16, 6200 MD, Maastricht, The Netherlands
| | - Marien I de Jonge
- Radboud Center for Infectious Diseases, Section Pediatric Infectious Diseases, Laboratory of Medical Immunology, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
| | - Gosse J Adema
- Department of Radiation Oncology, Radiotherapy & OncoImmunology Laboratory, Radboud Institute for Molecular Life Sciences, Radboud University Medical Center, Geert Grooteplein Zuid 32, Nijmegen, The Netherlands
| | - Nicola Zamboni
- Institute of Molecular Systems Biology, ETH Zürich, Zürich, Switzerland
| | - Thomas Boltje
- Cluster for Molecular Chemistry, Institute for Molecules and Materials, Radboud University Nijmegen, Heyendaalseweg 135, Nijmegen, The Netherlands
| | - Dirk J Lefeber
- Translational Metabolic Laboratory, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands.,Department of Neurology, Donders Institute for Brain, Cognition and Behavior, Radboud University Medical Center, Geert Grooteplein 10, 6525 GA, Nijmegen, The Netherlands
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5
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Cornish-Bowden A, Cárdenas ML. The essence of life revisited: how theories can shed light on it. Theory Biosci 2021; 141:105-123. [PMID: 33956294 PMCID: PMC8101340 DOI: 10.1007/s12064-021-00342-w] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/20/2020] [Accepted: 03/23/2021] [Indexed: 12/12/2022]
Abstract
Disagreement over whether life is inevitable when the conditions can support life remains unresolved, but calculations show that self-organization can arise naturally from purely random effects. Closure to efficient causation, or the need for all specific catalysts used by an organism to be produced internally, implies that a true model of an organism cannot exist, though this does not exclude the possibility that some characteristics can be simulated. Such simulations indicate that there is a limit to how small a self-organizing system can be: much smaller than a bacterial cell, but around the size of a typical virus particle. All current theories of life incorporate, at least implicitly, the idea of catalysis, but they largely ignore the need for metabolic regulation.
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6
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Mining novel cell glycolysis related gene markers that can predict the survival of colon adenocarcinoma patients. Biosci Rep 2021; 40:225964. [PMID: 32744303 PMCID: PMC7426632 DOI: 10.1042/bsr20201427] [Citation(s) in RCA: 11] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/04/2020] [Revised: 07/27/2020] [Accepted: 07/31/2020] [Indexed: 12/20/2022] Open
Abstract
Colon adenocarcinoma (COAD) is a malignant gastrointestinal tumor, often occurring in the left colon, which is regulated by glycolysis-related processes. In past studies, multiple genes that influence the prognosis for survival have been discovered through bioinformatics analysis. However, the prediction of disease prognosis using a single gene is not an accurate method. In the present study, a mechanistic model was established to achieve better prediction for the prognosis of COAD. COAD-related data downloaded from The Cancer Genome Atlas (TCGA) were correlated with the glycolysis process using gene set enrichment analysis (GSEA) to determine the glycolysis-related genes that regulate COAD. Using COX regression analysis, glycolysis-related genes associated with the prognosis of COAD were identified, and the genes screened to establish a predictive model. The risk scores of this model were correlated with relevant clinical data to obtain a connection diagram between the model and survival rate, tumor characteristic data, etc. Finally, genes in the model were correlated with cells in the tumor microenvironment, finding that they affected specific immune cells in the model. Seven genes related to glycolysis were identified (PPARGC1A, DLAT, 6PC2, P4HA1, STC2, ANKZF1, and GPC1), which affect the prognosis of patients with COAD and constitute the model for prediction of survival of COAD patients.
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Abstract
Drug metabolizing enzymes catalyze the biotransformation of many of drugs and chemicals. The drug metabolizing enzymes are distributed among several evolutionary families and catalyze a range of detoxication reactions, including oxidation/reduction, conjugative, and hydrolytic reactions that serve to detoxify potentially toxic compounds. This detoxication function requires that drug metabolizing enzymes exhibit substrate promiscuity. In addition to their catalytic functions, many drug metabolizing enzymes possess functions unrelated to or in addition to catalysis. Such proteins are termed 'moonlighting proteins' and are defined as proteins with multiple biochemical or biophysical functions that reside in a single protein. This review discusses the diverse moonlighting functions of drug metabolizing enzymes and the roles they play in physiological functions relating to reproduction, vision, cell signaling, cancer, and transport. Further research will likely reveal new examples of moonlighting functions of drug metabolizing enzymes.
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Affiliation(s)
- Philip G Board
- John Curtin School of Medical Research, ANU College of Health and Medicine, The Australian National University, Canberra, ACT, Australia
| | - M W Anders
- Department of Pharmacology and Physiology, University of Rochester Medical Center, New York, NY, USA
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8
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Dienel GA. Hypothesis: A Novel Neuroprotective Role for Glucose-6-phosphatase (G6PC3) in Brain-To Maintain Energy-Dependent Functions Including Cognitive Processes. Neurochem Res 2020; 45:2529-2552. [PMID: 32815045 DOI: 10.1007/s11064-020-03113-z] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/30/2020] [Revised: 08/10/2020] [Accepted: 08/13/2020] [Indexed: 12/11/2022]
Abstract
The isoform of glucose-6-phosphatase in liver, G6PC1, has a major role in whole-body glucose homeostasis, whereas G6PC3 is widely distributed among organs but has poorly-understood functions. A recent, elegant analysis of neutrophil dysfunction in G6PC3-deficient patients revealed G6PC3 is a neutrophil metabolite repair enzyme that hydrolyzes 1,5-anhydroglucitol-6-phosphate, a toxic metabolite derived from a glucose analog present in food. These patients exhibit a spectrum of phenotypic characteristics and some have learning disabilities, revealing a potential linkage between cognitive processes and G6PC3 activity. Previously-debated and discounted functions for brain G6PC3 include causing an ATP-consuming futile cycle that interferes with metabolic brain imaging assays and a nutritional role involving astrocyte-neuron glucose-lactate trafficking. Detailed analysis of the anhydroglucitol literature reveals that it competes with glucose for transport into brain, is present in human cerebrospinal fluid, and is phosphorylated by hexokinase. Anhydroglucitol-6-phosphate is present in rodent brain and other organs where its accumulation can inhibit hexokinase by competition with ATP. Calculated hexokinase inhibition indicates that energetics of brain and erythrocytes would be more adversely affected by anhydroglucitol-6-phosphate accumulation than heart. These findings strongly support the paradigm-shifting hypothesis that brain G6PC3 removes a toxic metabolite, thereby maintaining brain glucose metabolism- and ATP-dependent functions, including cognitive processes.
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Affiliation(s)
- Gerald A Dienel
- Department of Neurology, University of Arkansas for Medical Sciences, 4301 W. Markham St., Mail Slot 500, Little Rock, AR, 72205, USA.
- Department of Cell Biology and Physiology, University of New Mexico School of Medicine, Albuquerque, NM, 87131, USA.
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9
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Wang S, Alseekh S, Fernie AR, Luo J. The Structure and Function of Major Plant Metabolite Modifications. MOLECULAR PLANT 2019; 12:899-919. [PMID: 31200079 DOI: 10.1016/j.molp.2019.06.001] [Citation(s) in RCA: 189] [Impact Index Per Article: 37.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2019] [Revised: 05/27/2019] [Accepted: 06/04/2019] [Indexed: 05/23/2023]
Abstract
Plants produce a myriad of structurally and functionally diverse metabolites that play many different roles in plant growth and development and in plant response to continually changing environmental conditions as well as abiotic and biotic stresses. This metabolic diversity is, to a large extent, due to chemical modification of the basic skeletons of metabolites. Here, we review the major known plant metabolite modifications and summarize the progress that has been achieved and the challenges we are facing in the field. We focus on discussing both technical and functional aspects in studying the influences that various modifications have on biosynthesis, degradation, transport, and storage of metabolites, as well as their bioactivity and toxicity. Finally, we discuss some emerging insights into the evolution of metabolic pathways and metabolite functionality.
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Affiliation(s)
- Shouchuang Wang
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 572208, China
| | - Saleh Alseekh
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany; Centre of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria
| | - Alisdair R Fernie
- Max Planck Institute of Molecular Plant Physiology, Potsdam-Golm 14476, Germany; Centre of Plant Systems Biology and Biotechnology, Plovdiv 4000, Bulgaria.
| | - Jie Luo
- Hainan Key Laboratory for Sustainable Utilization of Tropical Bioresource, College of Tropical Crops, Hainan University, Haikou 572208, China; National Key Laboratory of Crop Genetic Improvement and National Center of Plant Gene Research (Wuhan), Huazhong Agricultural University, Wuhan 430070, China.
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10
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Abstract
Glucose is the long-established, obligatory fuel for brain that fulfills many critical functions, including ATP production, oxidative stress management, and synthesis of neurotransmitters, neuromodulators, and structural components. Neuronal glucose oxidation exceeds that in astrocytes, but both rates increase in direct proportion to excitatory neurotransmission; signaling and metabolism are closely coupled at the local level. Exact details of neuron-astrocyte glutamate-glutamine cycling remain to be established, and the specific roles of glucose and lactate in the cellular energetics of these processes are debated. Glycolysis is preferentially upregulated during brain activation even though oxygen availability is sufficient (aerobic glycolysis). Three major pathways, glycolysis, pentose phosphate shunt, and glycogen turnover, contribute to utilization of glucose in excess of oxygen, and adrenergic regulation of aerobic glycolysis draws attention to astrocytic metabolism, particularly glycogen turnover, which has a high impact on the oxygen-carbohydrate mismatch. Aerobic glycolysis is proposed to be predominant in young children and specific brain regions, but re-evaluation of data is necessary. Shuttling of glucose- and glycogen-derived lactate from astrocytes to neurons during activation, neurotransmission, and memory consolidation are controversial topics for which alternative mechanisms are proposed. Nutritional therapy and vagus nerve stimulation are translational bridges from metabolism to clinical treatment of diverse brain disorders.
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Affiliation(s)
- Gerald A Dienel
- Department of Neurology, University of Arkansas for Medical Sciences , Little Rock, Arkansas ; and Department of Cell Biology and Physiology, University of New Mexico , Albuquerque, New Mexico
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12
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Genotype to phenotype mapping still needs underpinning by research in metabolism and enzymology. Biosci Rep 2018; 38:BSR20180520. [PMID: 29848765 PMCID: PMC6013700 DOI: 10.1042/bsr20180520] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/14/2018] [Revised: 05/29/2018] [Accepted: 05/29/2018] [Indexed: 11/17/2022] Open
Abstract
The article ‘Evidence that the metabolite repair enzyme NAD(P)HX epimerase has a moonlighting function’ by Niehaus et al. published in this issue illustrates a number of the problems that still arise when attempting to translate genotypes to phenotypes, such as for interpreting mutant phenotypes or building genome-scale metabolic models. In this case, the mutation concerned appears to map to an enzyme in one of the little-known but essential metabolite repair pathways that have been discovered in recent years. However, the bioinformatic and experimental evidence presented suggests that the annotated enzyme activity of the mutated gene product, whilst correct, accounts neither for the phenotype nor for the chromosomal and transcriptional associations of the gene. The bioinformatic and metabolomic evidence presented points to an additional but important role for the gene product in pyridoxal phosphate homoeostasis, thus adding the enzyme to the expanding list of those with a ‘moonlighting function’.
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Ellens KW, Christian N, Singh C, Satagopam VP, May P, Linster CL. Confronting the catalytic dark matter encoded by sequenced genomes. Nucleic Acids Res 2017; 45:11495-11514. [PMID: 29059321 PMCID: PMC5714238 DOI: 10.1093/nar/gkx937] [Citation(s) in RCA: 52] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/18/2017] [Accepted: 10/03/2017] [Indexed: 01/02/2023] Open
Abstract
The post-genomic era has provided researchers with a deluge of protein sequences. However, a significant fraction of the proteins encoded by sequenced genomes remains without an identified function. Here, we aim at determining how many enzymes of uncertain or unknown function are still present in the Saccharomyces cerevisiae and human proteomes. Using information available in the Swiss-Prot, BRENDA and KEGG databases in combination with a Hidden Markov Model-based method, we estimate that >600 yeast and 2000 human proteins (>30% of their proteins of unknown function) are enzymes whose precise function(s) remain(s) to be determined. This illustrates the impressive scale of the ‘unknown enzyme problem’. We extensively review classical biochemical as well as more recent systematic experimental and computational approaches that can be used to support enzyme function discovery research. Finally, we discuss the possible roles of the elusive catalysts in light of recent developments in the fields of enzymology and metabolism as well as the significance of the unknown enzyme problem in the context of metabolic modeling, metabolic engineering and rare disease research.
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Affiliation(s)
- Kenneth W Ellens
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Nils Christian
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Charandeep Singh
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Venkata P Satagopam
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Patrick May
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
| | - Carole L Linster
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, L-4362 Esch-sur-Alzette, Luxembourg
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14
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Synthetic metabolism: metabolic engineering meets enzyme design. Curr Opin Chem Biol 2017; 37:56-62. [PMID: 28152442 DOI: 10.1016/j.cbpa.2016.12.023] [Citation(s) in RCA: 149] [Impact Index Per Article: 21.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2016] [Revised: 12/15/2016] [Accepted: 12/16/2016] [Indexed: 01/29/2023]
Abstract
Metabolic engineering aims at modifying the endogenous metabolic network of an organism to harness it for a useful biotechnological task, for example, production of a value-added compound. Several levels of metabolic engineering can be defined and are the topic of this review. Basic 'copy, paste and fine-tuning' approaches are limited to the structure of naturally existing pathways. 'Mix and match' approaches freely recombine the repertoire of existing enzymes to create synthetic metabolic networks that are able to outcompete naturally evolved pathways or redirect flux toward non-natural products. The space of possible metabolic solution can be further increased through approaches including 'new enzyme reactions', which are engineered on the basis of known enzyme mechanisms. Finally, by considering completely 'novel enzyme chemistries' with de novo enzyme design, the limits of nature can be breached to derive the most advanced form of synthetic pathways. We discuss the challenges and promises associated with these different metabolic engineering approaches and illuminate how enzyme engineering is expected to take a prime role in synthetic metabolic engineering for biotechnology, chemical industry and agriculture of the future.
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15
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Hanson AD, Henry CS, Fiehn O, de Crécy-Lagard V. Metabolite Damage and Metabolite Damage Control in Plants. ANNUAL REVIEW OF PLANT BIOLOGY 2016; 67:131-52. [PMID: 26667673 DOI: 10.1146/annurev-arplant-043015-111648] [Citation(s) in RCA: 28] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/23/2023]
Abstract
It is increasingly clear that (a) many metabolites undergo spontaneous or enzyme-catalyzed side reactions in vivo, (b) the damaged metabolites formed by these reactions can be harmful, and (c) organisms have biochemical systems that limit the buildup of damaged metabolites. These damage-control systems either return a damaged molecule to its pristine state (metabolite repair) or convert harmful molecules to harmless ones (damage preemption). Because all organisms share a core set of metabolites that suffer the same chemical and enzymatic damage reactions, certain damage-control systems are widely conserved across the kingdoms of life. Relatively few damage reactions and damage-control systems are well known. Uncovering new damage reactions and identifying the corresponding damaged metabolites, damage-control genes, and enzymes demands a coordinated mix of chemistry, metabolomics, cheminformatics, biochemistry, and comparative genomics. This review illustrates the above points using examples from plants, which are at least as prone to metabolite damage as other organisms.
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Affiliation(s)
| | - Christopher S Henry
- Mathematics and Computer Science Division, Argonne National Laboratory, Argonne, Illinois 60439;
- Computation Institute, University of Chicago, Chicago, Illinois 60637
| | - Oliver Fiehn
- Genome Center, University of California, Davis, California 95616;
| | - Valérie de Crécy-Lagard
- Microbiology and Cell Science Department, University of Florida, Gainesville, Florida 32611; ,
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16
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Kožich V, Krijt J, Sokolová J, Melenovská P, Ješina P, Vozdek R, Majtán T, Kraus JP. Thioethers as markers of hydrogen sulfide production in homocystinurias. Biochimie 2016; 126:14-20. [PMID: 26791043 DOI: 10.1016/j.biochi.2016.01.001] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/14/2015] [Accepted: 01/08/2016] [Indexed: 01/20/2023]
Abstract
Two enzymes in the transsulfuration pathway of homocysteine -cystathionine beta-synthase (CBS) and gamma-cystathionase (CTH)-use cysteine and/or homocysteine to produce the important signaling molecule hydrogen sulfide (H2S) and simultaneously the thioethers lanthionine, cystathionine or homolanthionine. In this study we explored whether impaired flux of substrates for H2S synthesis and/or deficient enzyme activities alter production of hydrogen sulfide in patients with homocystinurias. As an indirect measure of H2S synthesis we determined by LC-MS/MS concentrations of thioethers in plasma samples from 33 patients with different types of homocystinurias, in 8 patient derived fibroblast cell lines, and as reaction products of seven purified mutant CBS enzymes. Since chaperoned recombinant mutant CBS enzymes retained capacity of H2S synthesis in vitro it can be stipulated that deficient CBS activity in vivo may impair H2S production. Indeed, in patients with classical homocystinuria we observed significantly decreased cystathionine and lanthionine concentrations in plasma (46% and 74% of median control levels, respectively) and significantly lower cystathionine in fibroblasts (8% of median control concentrations) indicating that H2S production from cysteine and homocysteine may be also impaired. In contrast, the grossly elevated plasma levels of homolanthionine in CBS deficient patients (32-times elevation compared to median of controls) clearly demonstrates a simultaneous overproduction of H2S from homocysteine by CTH. In the remethylation defects the accumulation of homocysteine and the increased flux of metabolites through the transsulfuration pathway resulted in elevation of cystathionine and homolanthionine (857% and 400% of median control values, respectively) indicating a possibility of an increased biosynthesis of H2S by both CBS and CTH. This study shows clearly disturbed thioether concentrations in homocystinurias, and modeling using these data indicates that H2S synthesis may be increased in these conditions. Further studies are needed to confirm our findings and to explore the possible implications for pathophysiology of these disorders.
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Affiliation(s)
- Viktor Kožich
- Institute of Inherited Metabolic Disorders, Charles University in Prague-First Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic.
| | - Jakub Krijt
- Institute of Inherited Metabolic Disorders, Charles University in Prague-First Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Jitka Sokolová
- Institute of Inherited Metabolic Disorders, Charles University in Prague-First Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Petra Melenovská
- Institute of Inherited Metabolic Disorders, Charles University in Prague-First Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Pavel Ješina
- Institute of Inherited Metabolic Disorders, Charles University in Prague-First Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Roman Vozdek
- Institute of Inherited Metabolic Disorders, Charles University in Prague-First Faculty of Medicine and General University Hospital in Prague, Prague, Czech Republic
| | - Tomáš Majtán
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
| | - Jan P Kraus
- Department of Pediatrics, University of Colorado School of Medicine, Aurora, CO, USA
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