1
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Hazra S, Begley TP. Alkylcysteine Sulfoxide C-S Monooxygenase Uses a Flavin-Dependent Pummerer Rearrangement. J Am Chem Soc 2023; 145:11933-11938. [PMID: 37229602 PMCID: PMC10863075 DOI: 10.1021/jacs.3c03545] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/05/2023] [Indexed: 05/27/2023]
Abstract
Flavoenzymes are highly versatile and participate in the catalysis of a wide range of reactions, including key reactions in the metabolism of sulfur-containing compounds. S-Alkyl cysteine is formed primarily by the degradation of S-alkyl glutathione generated during electrophile detoxification. A recently discovered S-alkyl cysteine salvage pathway uses two flavoenzymes (CmoO and CmoJ) to dealkylate this metabolite in soil bacteria. CmoO catalyzes a stereospecific sulfoxidation, and CmoJ catalyzes the cleavage of one of the sulfoxide C-S bonds in a new reaction of unknown mechanism. In this paper, we investigate the mechanism of CmoJ. We provide experimental evidence that eliminates carbanion and radical intermediates and conclude that the reaction proceeds via an unprecedented enzyme-mediated modified Pummerer rearrangement. The elucidation of the mechanism of CmoJ adds a new motif to the flavoenzymology of sulfur-containing natural products and demonstrates a new strategy for the enzyme-catalyzed cleavage of C-S bonds.
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Affiliation(s)
- Sohan Hazra
- Department of Chemistry, Texas A&M University, College
Station, Texas 77843, United States
| | - Tadhg P. Begley
- Department of Chemistry, Texas A&M University, College
Station, Texas 77843, United States
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2
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Bremer E, Calteau A, Danchin A, Harwood C, Helmann JD, Médigue C, Palsson BO, Sekowska A, Vallenet D, Zuniga A, Zuniga C. A model industrial workhorse:
Bacillus subtilis
strain 168 and its genome after a quarter of a century. Microb Biotechnol 2023; 16:1203-1231. [PMID: 37002859 DOI: 10.1111/1751-7915.14257] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/01/2023] [Accepted: 03/20/2023] [Indexed: 04/04/2023] Open
Abstract
The vast majority of genomic sequences are automatically annotated using various software programs. The accuracy of these annotations depends heavily on the very few manual annotation efforts that combine verified experimental data with genomic sequences from model organisms. Here, we summarize the updated functional annotation of Bacillus subtilis strain 168, a quarter century after its genome sequence was first made public. Since the last such effort 5 years ago, 1168 genetic functions have been updated, allowing the construction of a new metabolic model of this organism of environmental and industrial interest. The emphasis in this review is on new metabolic insights, the role of metals in metabolism and macromolecule biosynthesis, functions involved in biofilm formation, features controlling cell growth, and finally, protein agents that allow class discrimination, thus allowing maintenance management, and accuracy of all cell processes. New 'genomic objects' and an extensive updated literature review have been included for the sequence, now available at the International Nucleotide Sequence Database Collaboration (INSDC: AccNum AL009126.4).
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Affiliation(s)
- Erhard Bremer
- Department of Biology, Laboratory for Microbiology and Center for Synthetic Microbiology (SYNMIKRO) Philipps‐University Marburg Marburg Germany
| | - Alexandra Calteau
- LABGeM, Génomique Métabolique, CEA, Genoscope, Institut de Biologie François Jacob Université d'Évry, Université Paris‐Saclay, CNRS Évry France
| | - Antoine Danchin
- School of Biomedical Sciences, Li KaShing Faculty of Medicine Hong Kong University Pokfulam SAR Hong Kong China
| | - Colin Harwood
- Centre for Bacterial Cell Biology, Biosciences Institute Newcastle University Baddiley Clark Building Newcastle upon Tyne UK
| | - John D. Helmann
- Department of Microbiology Cornell University Ithaca New York USA
| | - Claudine Médigue
- LABGeM, Génomique Métabolique, CEA, Genoscope, Institut de Biologie François Jacob Université d'Évry, Université Paris‐Saclay, CNRS Évry France
| | - Bernhard O. Palsson
- Department of Bioengineering University of California San Diego La Jolla USA
| | | | - David Vallenet
- LABGeM, Génomique Métabolique, CEA, Genoscope, Institut de Biologie François Jacob Université d'Évry, Université Paris‐Saclay, CNRS Évry France
| | - Abril Zuniga
- Department of Biology San Diego State University San Diego California USA
| | - Cristal Zuniga
- Bioinformatics and Medical Informatics Graduate Program San Diego State University San Diego California USA
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3
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Hillmann KB, Goethel ME, Erickson NA, Niehaus TD. Identification of a S-(2-succino)cysteine breakdown pathway that uses a novel S-(2-succino) lyase. J Biol Chem 2022; 298:102639. [PMID: 36309089 PMCID: PMC9706529 DOI: 10.1016/j.jbc.2022.102639] [Citation(s) in RCA: 4] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/10/2022] [Revised: 10/18/2022] [Accepted: 10/20/2022] [Indexed: 11/07/2022] Open
Abstract
Succination is the spontaneous reaction between the respiratory intermediate fumarate and cellular thiols that forms stable S-(2-succino)-adducts such as S-(2-succino)cysteine (2SC). 2SC is a biomarker for conditions associated with elevated fumarate levels, including diabetes, obesity, and certain cancers, and succination likely contributes to disease progression. Bacillus subtilis has a yxe operon-encoded breakdown pathway for 2SC that involves three distinct enzymatic conversions. The first step is N-acetylation of 2SC by YxeL to form N-acetyl-2SC (2SNAC). YxeK catalyzes the oxygenation of 2SNAC, resulting in its breakdown to oxaloacetate and N-acetylcysteine, which is deacetylated by YxeP to give cysteine. The monooxygenase YxeK is key to the pathway but is rare, with close homologs occurring infrequently in prokaryote and fungal genomes. The existence of additional 2SC breakdown pathways was not known prior to this study. Here, we used comparative genomics to identify a S-(2-succino) lyase (2SL) that replaces yxeK in some yxe gene clusters. 2SL genes from Enterococcus italicus and Dickeya dadantii complement B. subtilis yxeK mutants. We also determined that recombinant 2SL enzymes efficiently break down 2SNAC into fumarate and N-acetylcysteine, can perform the reverse reaction, and have minor activity against 2SC and other small molecule thiols. The strong preferences both YxeK and 2SL enzymes have for 2SNAC indicate that 2SC acetylation is a conserved breakdown step. The identification of a second naturally occurring 2SC breakdown pathway underscores the importance of 2SC catabolism and defines a general strategy for 2SC breakdown involving acetylation, breakdown, and deacetylation.
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4
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Hazra S, Bhandari DM, Krishnamoorthy K, Sekowska A, Danchin A, Begley TP. Cysteine Dealkylation in Bacillus subtilis by a Novel Flavin-Dependent Monooxygenase. Biochemistry 2022; 61:952-955. [PMID: 35584544 DOI: 10.1021/acs.biochem.2c00020] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
In this paper, we describe the biochemical reconstitution of a cysteine salvage pathway and the biochemical characterization of each of the five enzymes involved. The salvage begins with amine acetylation of S-alkylcysteine, followed by thioether oxidation. The C-S bond of the resulting sulfoxide is cleaved using a new flavoenzyme catalytic motif to give N-acetylcysteine sulfenic acid. This is then reduced to the thiol and deacetylated to complete the salvage pathway. We propose that this pathway is important in the catabolism of alkylated cysteine generated by proteolysis of alkylated glutathione formed in the detoxification of a wide range of electrophiles.
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Affiliation(s)
- Sohan Hazra
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | - Dhananjay M Bhandari
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
| | | | | | | | - Tadhg P Begley
- Department of Chemistry, Texas A&M University, College Station, Texas 77843, United States
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5
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Listeria monocytogenes TcyKLMN Cystine/Cysteine Transporter Facilitates Glutathione Synthesis and Virulence Gene Expression. mBio 2022; 13:e0044822. [PMID: 35435705 PMCID: PMC9239247 DOI: 10.1128/mbio.00448-22] [Citation(s) in RCA: 7] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Bacterial pathogens sense the repertoire of metabolites in the mammalian niche and use this information to shift into the pathogenic state to accomplish a successful infection. Glutathione is a virulence-activating signal that is synthesized by
L. monocytogenes
during infection of mammalian cells.
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6
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Danchin A. In vivo, in vitro and in silico: an open space for the development of microbe-based applications of synthetic biology. Microb Biotechnol 2022; 15:42-64. [PMID: 34570957 PMCID: PMC8719824 DOI: 10.1111/1751-7915.13937] [Citation(s) in RCA: 10] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/11/2021] [Accepted: 09/14/2021] [Indexed: 12/24/2022] Open
Abstract
Living systems are studied using three complementary approaches: living cells, cell-free systems and computer-mediated modelling. Progresses in understanding, allowing researchers to create novel chassis and industrial processes rest on a cycle that combines in vivo, in vitro and in silico studies. This design-build-test-learn iteration loop cycle between experiments and analyses combines together physiology, genetics, biochemistry and bioinformatics in a way that keeps going forward. Because computer-aided approaches are not directly constrained by the material nature of the entities of interest, we illustrate here how this virtuous cycle allows researchers to explore chemistry which is foreign to that present in extant life, from whole chassis to novel metabolic cycles. Particular emphasis is placed on the importance of evolution.
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Affiliation(s)
- Antoine Danchin
- Kodikos LabsInstitut Cochin24 rue du Faubourg Saint‐JacquesParis75014France
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7
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Matthews A, Schönfelder J, Lagies S, Schleicher E, Kammerer B, Ellis HR, Stull F, Teufel R. Bacterial flavoprotein monooxygenase YxeK salvages toxic S-(2-succino)-adducts via oxygenolytic C-S bond cleavage. FEBS J 2021; 289:787-807. [PMID: 34510734 DOI: 10.1111/febs.16193] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/30/2021] [Revised: 08/18/2021] [Accepted: 09/09/2021] [Indexed: 01/23/2023]
Abstract
Thiol-containing nucleophiles such as cysteine react spontaneously with the citric acid cycle intermediate fumarate to form S-(2-succino)-adducts. In Bacillus subtilis, a salvaging pathway encoded by the yxe operon has recently been identified for the detoxification and exploitation of these compounds as sulfur sources. This route involves acetylation of S-(2-succino)cysteine to N-acetyl-2-succinocysteine, which is presumably converted to oxaloacetate and N-acetylcysteine, before a final deacetylation step affords cysteine. The critical oxidative cleavage of the C-S bond of N-acetyl-S-(2-succino)cysteine was proposed to depend on the predicted flavoprotein monooxygenase YxeK. Here, we characterize YxeK and verify its role in S-(2-succino)-adduct detoxification and sulfur metabolism. Detailed biochemical and mechanistic investigation of YxeK including 18 O-isotope-labeling experiments, homology modeling, substrate specificity tests, site-directed mutagenesis, and (pre-)steady-state kinetics provides insight into the enzyme's mechanism of action, which may involve a noncanonical flavin-N5-peroxide species for C-S bond oxygenolysis.
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Affiliation(s)
| | | | - Simon Lagies
- Institute of Organic Chemistry, University of Freiburg, Germany
| | - Erik Schleicher
- Institute of Physical Chemistry, University of Freiburg, Germany
| | - Bernd Kammerer
- Institute of Organic Chemistry, University of Freiburg, Germany.,BIOSS Center for Biological Signaling Studies, University of Freiburg, Germany
| | - Holly R Ellis
- Brody School of Medicine, East Carolina University, Greenville, NC, USA
| | - Frederick Stull
- Department of Chemistry, Western Michigan University, Kalamazoo, MI, USA
| | - Robin Teufel
- Faculty of Biology, University of Freiburg, Germany
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8
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Latimer LN, Russ ZN, Lucas J, Dueber JE. Exploration of Acetylation as a Base-Labile Protecting Group in Escherichia coli for an Indigo Precursor. ACS Synth Biol 2020; 9:2775-2783. [PMID: 32886882 DOI: 10.1021/acssynbio.0c00297] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Biochemical protecting groups are observed in natural metabolic pathways to control reactivity and properties of chemical intermediates; similarly, they hold promise as a tool for metabolic engineers to achieve the same goals. Protecting groups come with costs: lower yields from carbon, metabolic load to the production host, deprotection catalyst costs and kinetics limitations, and wastewater treatment of the group. Compared to glycosyl biochemical protection, such as glucosyl groups, acetylation can mitigate each of these costs. As an example application where these benefits could be valuable, we explored acetylation protection of indoxyl, the reactive precursor to the clothing dye, indigo. First, we demonstrated denim dyeing with chemically sourced indoxyl acetate by deprotection with base, showing results comparable to industry-standard denim dyeing. Second, we modified an Escherichia coli production host for improved indoxyl acetate stability by the knockout of 14 endogenous hydrolases. Cumulatively, these knockouts yielded a 67% reduction in the indoxyl acetate hydrolysis rate from 0.22 mmol/g DCW/h to 0.07 mmol/g DCW/h. To biosynthesize indoxyl acetate, we identified three promiscuous acetyltransferases which acetylate indoxyl in vivo. Indoxyl acetate titer, while low, was improved 50%, from 43 μM to 67 μM, in the hydrolase knockout strain compared to wild-type E. coli. Unfortunately, low millimolar concentrations of indoxyl acetate proved to be toxic to the E. coli production host; however, the principle of acetylation as a readily cleavable and low impact biochemical protecting group and the engineered hydrolase knockout production host should prove useful for other metabolic products.
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Affiliation(s)
- Luke N. Latimer
- Department of Chemistry, University of California, Berkeley, Berkeley, California 94720, United States
| | - Zachary N. Russ
- The UC Berkeley & UCSF Graduate Program in Bioengineering, Berkeley, California 94720, United States
- Department of Bioengineering, University of California, Berkeley, Berkeley, California 94720, United States
| | - James Lucas
- The UC Berkeley & UCSF Graduate Program in Bioengineering, Berkeley, California 94720, United States
- Department of Bioengineering, University of California, Berkeley, Berkeley, California 94720, United States
| | - John E. Dueber
- Department of Bioengineering, University of California, Berkeley, Berkeley, California 94720, United States
- Biological Systems & Engineering Division, Lawrence Berkeley National Laboratory, Berkeley, California 94720, United States
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9
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Dual functionality of the amyloid protein TasA in Bacillus physiology and fitness on the phylloplane. Nat Commun 2020; 11:1859. [PMID: 32313019 PMCID: PMC7171179 DOI: 10.1038/s41467-020-15758-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 11.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/10/2019] [Accepted: 03/27/2020] [Indexed: 02/07/2023] Open
Abstract
Bacteria can form biofilms that consist of multicellular communities embedded in an extracellular matrix (ECM). In Bacillus subtilis, the main protein component of the ECM is the functional amyloid TasA. Here, we study further the roles played by TasA in B. subtilis physiology and biofilm formation on plant leaves and in vitro. We show that ΔtasA cells exhibit a range of cytological symptoms indicative of excessive cellular stress leading to increased cell death. TasA associates to the detergent-resistant fraction of the cell membrane, and the distribution of the flotillin-like protein FloT is altered in ΔtasA cells. We propose that, in addition to a structural function during ECM assembly and interactions with plants, TasA contributes to the stabilization of membrane dynamics as cells enter stationary phase. The amyloid protein TasA is a main component of the extracellular matrix in Bacillus subtilis biofilms. Here the authors show that, in addition to a structural function during biofilm assembly and interactions with plants, TasA contributes to the stabilization of membrane dynamics during stationary phase.
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10
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Dunlap CA, Bowman MJ, Zeigler DR. Promotion of Bacillus subtilis subsp. inaquosorum, Bacillus subtilis subsp. spizizenii and Bacillus subtilis subsp. stercoris to species status. Antonie van Leeuwenhoek 2019; 113:1-12. [PMID: 31721032 DOI: 10.1007/s10482-019-01354-9] [Citation(s) in RCA: 33] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/17/2019] [Accepted: 10/26/2019] [Indexed: 12/12/2022]
Abstract
Bacillus subtilis currently encompasses four subspecies, Bacillus subtilis subsp. subtilis, Bacillus subtilis subsp. inaquosorum, Bacillus subtilis subsp. spizizenii and Bacillus subtilis subsp. stercoris. Several studies based on genomic comparisons have suggested these subspecies should be promoted to species status. Previously, one of the main reasons for leaving them as subspecies was the lack of distinguishing phenotypes. In this study, we used comparative genomics to determine the genes unique to each subspecies and used these to lead us to the unique phenotypes. The results show that one difference among the subspecies is they produce different bioactive secondary metabolites. B. subtilis subsp. spizizenii is shown conserve the genes to produce mycosubtilin, bacillaene and 3,3'-neotrehalosadiamine. B. subtilis subsp. inaquosorum is shown conserve the genes to produce bacillomycin F, fengycin and an unknown PKS/NRPS cluster. B. subtilis subsp. stercoris is shown conserve the genes to produce fengycin and an unknown PKS/NRPS cluster. While B. subtilis subsp. subtilis is shown to conserve the genes to produce 3,3'-neotrehalosadiamine. In addition, we update the chemotaxonomy and phenotyping to support their promotion to species status.
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Affiliation(s)
- Christopher A Dunlap
- Crop Bioprotection Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, 1815 North University Street, Peoria, IL, USA.
| | - Michael J Bowman
- Bioenergy Research Unit, National Center for Agricultural Utilization Research, Agricultural Research Service, United States Department of Agriculture, 1815 North University Street, Peoria, IL, USA
| | - Daniel R Zeigler
- Bacillus Genetic Stock Center, The Ohio State University, Columbus, OH, USA
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11
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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: 193] [Impact Index Per Article: 38.6] [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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12
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Zheng C, Guo S, Tennant WG, Pradhan PK, Black KA, Dos Santos PC. The Thioredoxin System Reduces Protein Persulfide Intermediates Formed during the Synthesis of Thio-Cofactors in Bacillus subtilis. Biochemistry 2019; 58:1892-1904. [PMID: 30855939 DOI: 10.1021/acs.biochem.9b00045] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The biosynthesis of Fe-S clusters and other thio-cofactors requires the participation of redox agents. A shared feature in these pathways is the formation of transient protein persulfides, which are susceptible to reduction by artificial reducing agents commonly used in reactions in vitro. These agents modulate the reactivity and catalytic efficiency of biosynthetic reactions and, in some cases, skew the enzymes' kinetic behavior, bypassing sulfur acceptors known to be critical for the functionality of these pathways in vivo. Here, we provide kinetic evidence for the selective reactivity of the Bacillus subtilis Trx (thioredoxin) system toward protein-bound persulfide intermediates. Our results demonstrate that the redox flux of the Trx system modulates the rate of sulfide production in cysteine desulfurase assays. Likewise, the activity of the Trx system is dependent on the rate of persulfide formation, suggesting the occurrence of coupled reaction schemes between both enzymatic systems in vitro. Inactivation of TrxA (thioredoxin) or TrxR (thioredoxin reductase) impairs the activity of Fe-S enzymes in B. subtilis, indicating the involvement of the Trx system in Fe-S cluster metabolism. Surprisingly, biochemical characterization of TrxA reveals that this enzyme is able to coordinate Fe-S species, resulting in the loss of its reductase activity. The inactivation of TrxA through the coordination of a labile cluster, combined with its proposed role as a physiological reducing agent in sulfur transfer pathways, suggests a model for redox regulation. These findings provide a potential link between redox regulation and Fe-S metabolism.
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Affiliation(s)
- Chenkang Zheng
- Department of Chemistry , Wake Forest University , Winston-Salem , North Carolina 27106 , United States
| | - Selina Guo
- Department of Chemistry , Wake Forest University , Winston-Salem , North Carolina 27106 , United States
| | - William G Tennant
- Department of Chemistry , Wake Forest University , Winston-Salem , North Carolina 27106 , United States
| | - Pradyumna K Pradhan
- Department of Chemistry , Wake Forest University , Winston-Salem , North Carolina 27106 , United States.,Department of Chemistry and Biochemistry , The University of North Carolina at Greensboro , Greensboro , North Carolina 27412 , United States
| | - Katherine A Black
- Department of Chemistry , Wake Forest University , Winston-Salem , North Carolina 27106 , United States.,Department of Medicine , Weill Cornell Medicine , New York , New York 10065 , United States
| | - Patricia C Dos Santos
- Department of Chemistry , Wake Forest University , Winston-Salem , North Carolina 27106 , United States
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13
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Morrison MD, Fajardo-Cavazos P, Nicholson WL. Comparison of Bacillus subtilis transcriptome profiles from two separate missions to the International Space Station. NPJ Microgravity 2019; 5:1. [PMID: 30623021 PMCID: PMC6323116 DOI: 10.1038/s41526-018-0061-0] [Citation(s) in RCA: 27] [Impact Index Per Article: 5.4] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/20/2018] [Accepted: 11/06/2018] [Indexed: 11/12/2022] Open
Abstract
The human spaceflight environment is notable for the unique factor of microgravity, which exerts numerous physiologic effects on macroscopic organisms, but how this environment may affect single-celled microbes is less clear. In an effort to understand how the microbial transcriptome responds to the unique environment of spaceflight, the model Gram-positive bacterium Bacillus subtilis was flown on two separate missions to the International Space Station in experiments dubbed BRIC-21 and BRIC-23. Cells were grown to late-exponential/early stationary phase, frozen, then returned to Earth for RNA-seq analysis in parallel with matched ground control samples. A total of 91 genes were significantly differentially expressed in both experiments; 55 exhibiting higher transcript levels in flight samples and 36 showing higher transcript levels in ground control samples. Genes upregulated in flight samples notably included those involved in biofilm formation, biotin and arginine biosynthesis, siderophores, manganese transport, toxin production and resistance, and sporulation inhibition. Genes preferentially upregulated in ground control samples notably included those responding to oxygen limitation, e.g., fermentation, anaerobic respiration, subtilosin biosynthesis, and anaerobic regulatory genes. The results indicated differences in oxygen availability between flight and ground control samples, likely due to differences in cell sedimentation and the toroidal shape assumed by the liquid cultures in microgravity.
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Affiliation(s)
- Michael D. Morrison
- Department of Microbiology and Cell Science, University of Florida, Merritt Island, FL USA
| | | | - Wayne L. Nicholson
- Department of Microbiology and Cell Science, University of Florida, Merritt Island, FL USA
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14
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Sekowska A, Ashida H, Danchin A. Revisiting the methionine salvage pathway and its paralogues. Microb Biotechnol 2019; 12:77-97. [PMID: 30306718 PMCID: PMC6302742 DOI: 10.1111/1751-7915.13324] [Citation(s) in RCA: 29] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/16/2018] [Revised: 08/24/2018] [Accepted: 09/14/2018] [Indexed: 12/17/2022] Open
Abstract
Methionine is essential for life. Its chemistry makes it fragile in the presence of oxygen. Aerobic living organisms have selected a salvage pathway (the MSP) that uses dioxygen to regenerate methionine, associated to a ratchet-like step that prevents methionine back degradation. Here, we describe the variation on this theme, developed across the tree of life. Oxygen appeared long after life had developed on Earth. The canonical MSP evolved from ancestors that used both predecessors of ribulose bisphosphate carboxylase oxygenase (RuBisCO) and methanethiol in intermediate steps. We document how these likely promiscuous pathways were also used to metabolize the omnipresent by-products of S-adenosylmethionine radical enzymes as well as the aromatic and isoprene skeleton of quinone electron acceptors.
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Affiliation(s)
- Agnieszka Sekowska
- Institute of Cardiometabolism and NutritionHôpital de la Pitié‐SalpêtrièreParisFrance
| | - Hiroki Ashida
- Graduate School of Human Development and EnvironmentKobe UniversityKobeJapan
| | - Antoine Danchin
- Institute of Cardiometabolism and NutritionHôpital de la Pitié‐SalpêtrièreParisFrance
- Institute of Synthetic BiologyShenzhen Institutes of Advanced StudiesShenzhenChina
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15
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Harnessing Underground Metabolism for Pathway Development. Trends Biotechnol 2019; 37:29-37. [DOI: 10.1016/j.tibtech.2018.08.001] [Citation(s) in RCA: 19] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2018] [Revised: 07/17/2018] [Accepted: 08/06/2018] [Indexed: 01/13/2023]
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16
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de Crécy-Lagard V, Haas D, Hanson AD. Newly-discovered enzymes that function in metabolite damage-control. Curr Opin Chem Biol 2018; 47:101-108. [PMID: 30268903 DOI: 10.1016/j.cbpa.2018.09.014] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/03/2018] [Revised: 08/19/2018] [Accepted: 09/11/2018] [Indexed: 01/26/2023]
Abstract
Enzymes of unknown function are estimated to make up around 25% of the sequenced proteome. In the past decade, over 20 conserved families have been shown to function in the metabolism of 'damaged' or abnormal metabolites that are wasteful and often toxic. These newly discovered damage-control enzymes either repair or inactivate the offending metabolites, or pre-empt their formation in the first place. Comparative genomics has been of prime importance in predicting the functions of damage-control enzymes and in guiding the biochemical and genetic tests required to validate these functions.
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Affiliation(s)
- Valérie de Crécy-Lagard
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA; Genetics Institute, University of Florida, Gainesville, FL, USA.
| | - Drago Haas
- Department of Microbiology and Cell Science, University of Florida, Gainesville, FL, USA
| | - Andrew D Hanson
- Horticultural Sciences Department, University of Florida, Gainesville, FL, USA
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17
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Beaudoin GAW, Li Q, Folz J, Fiehn O, Goodsell JL, Angerhofer A, Bruner SD, Hanson AD. Salvage of the 5-deoxyribose byproduct of radical SAM enzymes. Nat Commun 2018; 9:3105. [PMID: 30082730 PMCID: PMC6079011 DOI: 10.1038/s41467-018-05589-4] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Accepted: 07/12/2018] [Indexed: 11/16/2022] Open
Abstract
5-Deoxyribose is formed from 5′-deoxyadenosine, a toxic byproduct of radical S-adenosylmethionine (SAM) enzymes. The degradative fate of 5-deoxyribose is unknown. Here, we define a salvage pathway for 5-deoxyribose in bacteria, consisting of phosphorylation, isomerization, and aldol cleavage steps. Analysis of bacterial genomes uncovers widespread, unassigned three-gene clusters specifying a putative kinase, isomerase, and sugar phosphate aldolase. We show that the enzymes encoded by the Bacillus thuringiensis cluster, acting together in vitro, convert 5-deoxyribose successively to 5-deoxyribose 1-phosphate, 5-deoxyribulose 1-phosphate, and dihydroxyacetone phosphate plus acetaldehyde. Deleting the isomerase decreases the 5-deoxyribulose 1-phosphate pool size, and deleting either the isomerase or the aldolase increases susceptibility to 5-deoxyribose. The substrate preference of the aldolase is unique among family members, and the X-ray structure reveals an unusual manganese-dependent enzyme. This work defines a salvage pathway for 5-deoxyribose, a near-universal metabolite. 5-Deoxyribose is formed from 5′-deoxyadenosine, a toxic byproduct of radical S-adenosylmethionine enzymes. Here, the authors identify and biochemically characterize a bacterial salvage pathway for 5-deoxyribose, consisting of three enzymes, and solve the crystal structure of the key aldolase.
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Affiliation(s)
| | - Qiang Li
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA
| | - Jacob Folz
- NIH West Coast Metabolomics Center, UC Davis Genome Center, University of California Davis, Davis, CA, 95616, USA
| | - Oliver Fiehn
- NIH West Coast Metabolomics Center, UC Davis Genome Center, University of California Davis, Davis, CA, 95616, USA.,Biochemistry Department, King Abdulaziz University, Jeddah, 21589, Saudi Arabia
| | - Justin L Goodsell
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA
| | | | - Steven D Bruner
- Department of Chemistry, University of Florida, Gainesville, FL, 32611, USA.
| | - Andrew D Hanson
- Horticultural Sciences Department, University of Florida, Gainesville, FL, 32611, USA.
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18
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Danchin A, Ouzounis C, Tokuyasu T, Zucker JD. No wisdom in the crowd: genome annotation in the era of big data - current status and future prospects. Microb Biotechnol 2018; 11:588-605. [PMID: 29806194 PMCID: PMC6011933 DOI: 10.1111/1751-7915.13284] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022] Open
Abstract
Science and engineering rely on the accumulation and dissemination of knowledge to make discoveries and create new designs. Discovery-driven genome research rests on knowledge passed on via gene annotations. In response to the deluge of sequencing big data, standard annotation practice employs automated procedures that rely on majority rules. We argue this hinders progress through the generation and propagation of errors, leading investigators into blind alleys. More subtly, this inductive process discourages the discovery of novelty, which remains essential in biological research and reflects the nature of biology itself. Annotation systems, rather than being repositories of facts, should be tools that support multiple modes of inference. By combining deduction, induction and abduction, investigators can generate hypotheses when accurate knowledge is extracted from model databases. A key stance is to depart from 'the sequence tells the structure tells the function' fallacy, placing function first. We illustrate our approach with examples of critical or unexpected pathways, using MicroScope to demonstrate how tools can be implemented following the principles we advocate. We end with a challenge to the reader.
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Affiliation(s)
- Antoine Danchin
- Integromics, Institute of Cardiometabolism and Nutrition, Hôpital de la Pitié-Salpêtrière, 47 Boulevard de l'Hôpital, 75013, Paris, France
- School of Biomedical Sciences, Li KaShing Faculty of Medicine, Hong Kong University, 21 Sassoon Road, Pokfulam, Hong Kong
| | - Christos Ouzounis
- Biological Computation and Process Laboratory, Centre for Research and Technology Hellas, Chemical Process and Energy Resources Institute, Thessalonica, 57001, Greece
| | - Taku Tokuyasu
- Shenzhen Institutes of Advanced Technology, Institute of Synthetic Biology, Shenzhen University Town, 1068 Xueyuan Avenue, Shenzhen, China
| | - Jean-Daniel Zucker
- Integromics, Institute of Cardiometabolism and Nutrition, Hôpital de la Pitié-Salpêtrière, 47 Boulevard de l'Hôpital, 75013, Paris, France
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19
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Niehaus TD, Folz J, McCarty DR, Cooper AJL, Moraga Amador D, Fiehn O, Hanson AD. Identification of a metabolic disposal route for the oncometabolite S-(2-succino)cysteine in Bacillus subtilis. J Biol Chem 2018; 293:8255-8263. [PMID: 29626092 DOI: 10.1074/jbc.ra118.002925] [Citation(s) in RCA: 15] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/14/2018] [Revised: 04/04/2018] [Indexed: 01/21/2023] Open
Abstract
Cellular thiols such as cysteine spontaneously and readily react with the respiratory intermediate fumarate, resulting in the formation of stable S-(2-succino)-adducts. Fumarate-mediated succination of thiols increases in certain tumors and in response to glucotoxicity associated with diabetes. Therefore, S-(2-succino)-adducts such as S-(2-succino)cysteine (2SC) are considered oncometabolites and biomarkers for human disease. No disposal routes for S-(2-succino)-compounds have been reported prior to this study. Here, we show that Bacillus subtilis metabolizes 2SC to cysteine using a pathway encoded by the yxe operon. The first step is N-acetylation of 2SC followed by an oxygenation that we propose results in the release of oxaloacetate and N-acetylcysteine, which is deacetylated to give cysteine. Knockouts of the genes predicted to mediate each step in the pathway lose the ability to grow on 2SC as the sulfur source and accumulate the expected upstream metabolite(s). We further show that N-acetylation of 2SC relieves toxicity. This is the first demonstration of a metabolic disposal route for any S-(2-succino)-compound, paving the way toward the identification of corresponding pathways in other species.
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Affiliation(s)
- Thomas D Niehaus
- Horticultural Sciences Department, University of Florida, Gainesville, Florida 32611.
| | - Jacob Folz
- West Coast Metabolomics Center, University of California, Davis, California 95616
| | - Donald R McCarty
- Horticultural Sciences Department, University of Florida, Gainesville, Florida 32611
| | - Arthur J L Cooper
- Department of Biochemistry and Molecular Biology, New York Medical College, Valhalla, New York 10595
| | - David Moraga Amador
- Interdisciplinary Center for Biotechnology Research, University of Florida, Gainesville, Florida 32611
| | - Oliver Fiehn
- West Coast Metabolomics Center, University of California, Davis, California 95616
| | - Andrew D Hanson
- Horticultural Sciences Department, University of Florida, Gainesville, Florida 32611.
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20
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Danchin A, Sekowska A, Noria S. Functional Requirements in the Program and the Cell Chassis for Next-Generation Synthetic Biology. Synth Biol (Oxf) 2018. [DOI: 10.1002/9783527688104.ch5] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022] Open
Affiliation(s)
- Antoine Danchin
- Institute of Cardiometabolism and Nutrition; 47 boulevard de l'Hôpital Paris 75013 France
| | - Agnieszka Sekowska
- Institute of Cardiometabolism and Nutrition; 47 boulevard de l'Hôpital Paris 75013 France
| | - Stanislas Noria
- Fondation Fourmentin-Guilbert; 2 avenue du Pavé Neuf Noisy le Grand 93160 France
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21
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Borriss R, Danchin A, Harwood CR, Médigue C, Rocha EP, Sekowska A, Vallenet D. Bacillus subtilis, the model Gram-positive bacterium: 20 years of annotation refinement. Microb Biotechnol 2018; 11:3-17. [PMID: 29280348 PMCID: PMC5743806 DOI: 10.1111/1751-7915.13043] [Citation(s) in RCA: 65] [Impact Index Per Article: 10.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/08/2023] Open
Abstract
Genome annotation is, nowadays, performed via automatic pipelines that cannot discriminate between right and wrong annotations. Given their importance in increasing the accuracy of the genome annotations of other organisms, it is critical that the annotations of model organisms reflect the current annotation gold standard. The genome of Bacillus subtilis strain 168 was sequenced twenty years ago. Using a combination of inductive, deductive and abductive reasoning, we present a unique, manually curated annotation, essentially based on experimental data. This reveals how this bacterium lives in a plant niche, while carrying a paleome operating system common to Firmicutes and Tenericutes. Dozens of new genomic objects and an extensive literature survey have been included for the sequence available at the INSDC (AccNum AL009126.3). We also propose an extension to Demerec's nomenclature rules that will help investigators connect to this type of curated annotation via the use of common gene names.
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Affiliation(s)
- Rainer Borriss
- Department of PhytomedicineHumboldt‐Universität zu BerlinLentzeallee 55‐5714195BerlinGermany
| | - Antoine Danchin
- Hôpital de la Pitié‐SalpêtrièreInstitute of Cardiometabolism and Nutrition47 Boulevard de l'Hôpital75013ParisFrance
- School of Biomedical SciencesLi Kashing Faculty of MedicineUniversity of Hong Kong21 Sassoon RoadPok Fu LamSAR Hong KongChina
| | - Colin R. Harwood
- The Centre for Bacterial Cell BiologyNewcastle UniversityBaddiley‐Clark BuildingRichardson RoadNewcastle upon TyneNE2 4AXUK
| | - Claudine Médigue
- CEA DRF Genoscope LABGeMCNRS, UMR8030 Génomique MétaboliqueUniversité d'Evry Val d'EssonneUniversité Paris‐SaclayF‐91057EvryFrance
| | - Eduardo P.C. Rocha
- Microbial Evolutionary Genomics UnitInstitut Pasteur28 rue du Docteur Roux75724Paris Cedex 15France
| | - Agnieszka Sekowska
- Hôpital de la Pitié‐SalpêtrièreInstitute of Cardiometabolism and Nutrition47 Boulevard de l'Hôpital75013ParisFrance
| | - David Vallenet
- CEA DRF Genoscope LABGeMCNRS, UMR8030 Génomique MétaboliqueUniversité d'Evry Val d'EssonneUniversité Paris‐SaclayF‐91057EvryFrance
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22
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Zerbs S, Korajczyk PJ, Noirot PH, Collart FR. Transport capabilities of environmental Pseudomonads for sulfur compounds. Protein Sci 2017; 26:784-795. [PMID: 28127814 DOI: 10.1002/pro.3124] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/25/2016] [Revised: 01/16/2017] [Accepted: 01/17/2017] [Indexed: 11/11/2022]
Abstract
Sulfur is an essential element in plant rhizospheres and microbial activity plays a key role in increasing the biological availability of sulfur in soil environments. To better understand the mechanisms facilitating the exchange of sulfur-containing molecules in soil, we profiled the binding specificities of eight previously uncharacterized ABC transporter solute-binding proteins from plant-associated Pseudomonads. A high-throughput screening procedure indicated eighteen significant organosulfur binding ligands, with at least one high-quality screening hit for each protein target. Calorimetric and spectroscopic methods were used to validate the best ligand assignments and catalog the thermodynamic properties of the protein-ligand interactions. Two novel high-affinity ligand-binding activities were identified and quantified in this set of solute-binding proteins. Bacteria were cultured in minimal media with screening library components supplied as the sole sulfur sources, demonstrating that these organosulfur compounds can be metabolized and confirming the relevance of ligand assignments. These results expand the set of experimentally validated ligands amenable to transport by this ABC transporter family and demonstrate the complex range of protein-ligand interactions that can be accomplished by solute-binding proteins. Characterizing new nutrient import pathways provides insight into Pseudomonad metabolic capabilities which can be used to further interrogate bacterial survival and participation in soil and rhizosphere communities.
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Affiliation(s)
- Sarah Zerbs
- Biosciences Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, Illinois, 60439
| | - Peter J Korajczyk
- Biosciences Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, Illinois, 60439
| | - Philippe H Noirot
- Biosciences Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, Illinois, 60439
| | - Frank R Collart
- Biosciences Division, Argonne National Laboratory, 9700 S Cass Ave, Lemont, Illinois, 60439
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23
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Abstract
Genomic studies focus on key metabolites and pathways that, despite their obvious anthropocentric design, keep being 'predicted', while this is only finding again what is already known. As increasingly more genomes are sequenced, this lightpost effect may account at least in part for our failure to understand the function of a continuously growing number of genes. Core metabolism often goes astray, accidentally producing a variety of unexpected compounds. Catabolism of these forgotten metabolites makes an essential part of the functions coded in metagenomes. Here, I explore the fate of a limited number of those: compounds resulting from radical reactions and molecules derived from some reactive intermediates produced during normal metabolism. I try both to update investigators with the most recent literature and to uncover old articles that may open up new research avenues in the genome exploration of metabolism. This should allow us to foresee further developments in experimental genomics and genome annotation.
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Affiliation(s)
- Antoine Danchin
- Institute of Cardiometabolism and NutritionHôpital de la Pitié‐Salpêtrière47 Boulevard de l'HôpitalParis75013France
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24
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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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25
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26
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Dey S, North JA, Sriram J, Evans BS, Tabita FR. In Vivo Studies in Rhodospirillum rubrum Indicate That Ribulose-1,5-bisphosphate Carboxylase/Oxygenase (Rubisco) Catalyzes Two Obligatorily Required and Physiologically Significant Reactions for Distinct Carbon and Sulfur Metabolic Pathways. J Biol Chem 2015; 290:30658-68. [PMID: 26511314 DOI: 10.1074/jbc.m115.691295] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Indexed: 12/19/2022] Open
Abstract
All organisms possess fundamental metabolic pathways to ensure that needed carbon and sulfur compounds are provided to the cell in the proper chemical form and oxidation state. For most organisms capable of using CO2 as sole source of carbon, ribulose-1,5-bisphosphate (RuBP) carboxylase/oxygenase (Rubisco) catalyzes primary carbon dioxide assimilation. In addition, sulfur salvage pathways are necessary to ensure that key sulfur-containing compounds are both available and, where necessary, detoxified in the cell. Using knock-out mutations and metabolomics in the bacterium Rhodospirillum rubrum, we show here that Rubisco concurrently catalyzes key and essential reactions for seemingly unrelated but physiologically essential central carbon and sulfur salvage metabolic pathways of the cell. In this study, complementation and mutagenesis studies indicated that representatives of all known extant functional Rubisco forms found in nature are capable of simultaneously catalyzing reactions required for both CO2-dependent growth as well as growth using 5-methylthioadenosine as sole sulfur source under anaerobic photosynthetic conditions. Moreover, specific inactivation of the CO2 fixation reaction did not affect the ability of Rubisco to support anaerobic 5-methylthioadenosine metabolism, suggesting that the active site of Rubisco has evolved to ensure that this enzyme maintains both key functions. Thus, despite the coevolution of both functions, the active site of this protein may be differentially modified to affect only one of its key functions.
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Affiliation(s)
- Swati Dey
- From the Department of Microbiology, The Ohio State University, Columbus, Ohio 43210 and
| | - Justin A North
- From the Department of Microbiology, The Ohio State University, Columbus, Ohio 43210 and
| | - Jaya Sriram
- From the Department of Microbiology, The Ohio State University, Columbus, Ohio 43210 and
| | - Bradley S Evans
- the Donald Danforth Plant Science Center, St. Louis, Missouri, 63132
| | - F Robert Tabita
- From the Department of Microbiology, The Ohio State University, Columbus, Ohio 43210 and
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27
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A dual control mechanism synchronizes riboflavin and sulphur metabolism in Bacillus subtilis. Proc Natl Acad Sci U S A 2015; 112:14054-9. [PMID: 26494285 DOI: 10.1073/pnas.1515024112] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Key Words] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022] Open
Abstract
Flavin mononucleotide (FMN) riboswitches are genetic elements, which in many bacteria control genes responsible for biosynthesis and/or transport of riboflavin (rib genes). Cytoplasmic riboflavin is rapidly and almost completely converted to FMN by flavokinases. When cytoplasmic levels of FMN are sufficient ("high levels"), FMN binding to FMN riboswitches leads to a reduction of rib gene expression. We report here that the protein RibR counteracts the FMN-induced "turn-off" activities of both FMN riboswitches in Bacillus subtilis, allowing rib gene expression even in the presence of high levels of FMN. The reason for this secondary metabolic control by RibR is to couple sulfur metabolism with riboflavin metabolism.
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28
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de Lorenzo V, Sekowska A, Danchin A. Chemical reactivity drives spatiotemporal organisation of bacterial metabolism. FEMS Microbiol Rev 2014; 39:96-119. [PMID: 25227915 DOI: 10.1111/1574-6976.12089] [Citation(s) in RCA: 35] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/20/2023] Open
Abstract
In this review, we examine how bacterial metabolism is shaped by chemical constraints acting on the material and dynamic layout of enzymatic networks and beyond. These are moulded not only for optimisation of given metabolic objectives (e.g. synthesis of a particular amino acid or nucleotide) but also for curbing the detrimental reactivity of chemical intermediates. Besides substrate channelling, toxicity is avoided by barriers to free diffusion (i.e. compartments) that separate otherwise incompatible reactions, along with ways for distinguishing damaging vs. harmless molecules. On the other hand, enzymes age and their operating lifetime must be tuned to upstream and downstream reactions. This time dependence of metabolic pathways creates time-linked information, learning and memory. These features suggest that the physical structure of existing biosystems, from operon assemblies to multicellular development may ultimately stem from the need to restrain chemical damage and limit the waste inherent to basic metabolic functions. This provides a new twist of our comprehension of fundamental biological processes in live systems as well as practical take-home lessons for the forward DNA-based engineering of novel biological objects.
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Affiliation(s)
- Víctor de Lorenzo
- Systems Biology Program, Centro Nacional de Biotecnología CSIC, Cantoblanco-Madrid, Spain
| | - Agnieszka Sekowska
- AMAbiotics SAS, Institut du Cerveau et de la Moëlle Épinière, Hôpital de la Pitié-Salpêtrière, Paris, France
| | - Antoine Danchin
- AMAbiotics SAS, Institut du Cerveau et de la Moëlle Épinière, Hôpital de la Pitié-Salpêtrière, Paris, France
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