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Warneke R, Herzberg C, Klein M, Elfmann C, Dittmann J, Feussner K, Feussner I, Stülke J. Coenzyme A biosynthesis in Bacillus subtilis: discovery of a novel precursor metabolite for salvage and its uptake system. mBio 2024:e0177224. [PMID: 39194188 DOI: 10.1128/mbio.01772-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2024] [Accepted: 07/26/2024] [Indexed: 08/29/2024] Open
Abstract
The Gram-positive model bacterium Bacillus subtilis is used for many biotechnological applications, including the large-scale production of vitamins. For vitamin B5, a precursor for coenzyme A synthesis, there is so far no established fermentation process available, and the metabolic pathways that involve this vitamin are only partially understood. In this study, we have elucidated the complete pathways for the biosynthesis of pantothenate and coenzyme A in B. subtilis. Pantothenate can not only be synthesized but also be taken up from the medium. We have identified the enzymes and the transporter involved in the pantothenate biosynthesis and uptake. High-affinity vitamin B5 uptake in B. subtilis requires an ATP-driven energy coupling factor transporter with PanU (previously YhfU) as the substrate-specific subunit. Moreover, we have identified a salvage pathway for coenzyme A acquisition that acts on complex medium even in the absence of pantothenate synthesis. This pathway requires rewiring of sulfur metabolism resulting in the increased expression of a cysteine transporter. In the salvage pathway, the bacteria import cysteinopantetheine, a novel naturally occurring metabolite, using the cystine transport system TcyJKLMN. This work lays the foundation for the development of effective processes for vitamin B5 and coenzyme A production using B. subtilis. IMPORTANCE Vitamins are essential components of the diet of animals and humans. Vitamins are thus important targets for biotechnological production. While efficient fermentation processes have been developed for several vitamins, this is not the case for vitamin B5 (pantothenate), the precursor of coenzyme A. We have elucidated the complete pathway for coenzyme A biosynthesis in the biotechnological workhorse Bacillus subtilis. Moreover, a salvage pathway for coenzyme A synthesis was found in this study. Normally, this pathway depends on pantetheine; however, we observed activity of the salvage pathway on complex medium in mutants lacking the pantothenate biosynthesis pathway even in the absence of supplemented pantetheine. This required rewiring of metabolism by expressing a cystine transporter due to acquisition of mutations affecting the regulation of cysteine metabolism. This shows how the hidden "underground metabolism" can give rise to the rapid formation of novel metabolic pathways.
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Affiliation(s)
- Robert Warneke
- Department of General Microbiology, Institute for Microbiology & Genetics and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
| | - Christina Herzberg
- Department of General Microbiology, Institute for Microbiology & Genetics and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
| | - Moritz Klein
- Department of Plant Biochemistry, Albrecht-von-Haller Institute and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
| | - Christoph Elfmann
- Department of General Microbiology, Institute for Microbiology & Genetics and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
| | - Josi Dittmann
- Department of General Microbiology, Institute for Microbiology & Genetics and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
| | - Kirstin Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller Institute and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
- Service Unit for Metabolomics and Lipidomics, Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
| | - Ivo Feussner
- Department of Plant Biochemistry, Albrecht-von-Haller Institute and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
| | - Jörg Stülke
- Department of General Microbiology, Institute for Microbiology & Genetics and Göttingen Center for Molecular Biosciences, University of Göttingen, Göttingen, Germany
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2
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Tikhomirova A, Rahman MM, Kidd SP, Ferrero RL, Roujeinikova A. Cysteine and resistance to oxidative stress: implications for virulence and antibiotic resistance. Trends Microbiol 2024; 32:93-104. [PMID: 37479622 DOI: 10.1016/j.tim.2023.06.010] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/18/2023] [Revised: 06/28/2023] [Accepted: 06/30/2023] [Indexed: 07/23/2023]
Abstract
Reactive oxygen species (ROS), including the superoxide radical anion (O2•-), hydrogen peroxide (H2O2), and the hydroxyl radical (•HO), are inherent components of bacterial metabolism in an aerobic environment. Bacteria also encounter exogenous ROS, such as those produced by the host cells during the respiratory burst. As ROS have the capacity to damage bacterial DNA, proteins, and lipids, detoxification of ROS is critical for bacterial survival. It has been recently recognised that low-molecular-weight (LMW) thiols play a central role in this process. Here, we review the emerging role of cysteine in bacterial resistance to ROS with a link to broader elements of bacterial lifestyle closely associated with cysteine-mediated oxidative stress response, including virulence and antibiotic resistance.
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Affiliation(s)
- Alexandra Tikhomirova
- Monash University, Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Melbourne, VIC 3800, Australia
| | - Mohammad M Rahman
- University of Kentucky, Department of Microbiology, Immunology and Molecular Genetics, Lexington, KY, USA
| | - Stephen P Kidd
- University of Adelaide, Department of Molecular and Biomedical Sciences, School of Biological Sciences, Adelaide, SA 5005, Australia; University of Adelaide, Research Centre for Infectious Disease (RCID) and Australian Centre for Antimicrobial Resistance Ecology (ACARE), Adelaide, SA 5005, Australia
| | - Richard L Ferrero
- Monash University, Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Melbourne, VIC 3800, Australia; Hudson Institute of Medical Research, Centre for Innate Immunity and Infectious Diseases, Melbourne, VIC 3168, Australia; Monash University, Department of Molecular and Translational Science, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Melbourne, VIC 3800, Australia
| | - Anna Roujeinikova
- Monash University, Department of Microbiology, Infection and Immunity Program, Monash Biomedicine Discovery Institute, Melbourne, VIC 3800, Australia; Monash University, Department of Biochemistry and Molecular Biology, Melbourne, VIC 3800, Australia.
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3
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Ev LD, Poloni JDF, Damé-Teixeira N, Arthur RA, Corralo DJ, Henz SL, Do T, Maltz M, Parolo CCF. Hub genes and pathways related to caries-free dental biofilm: clinical metatranscriptomic study. Clin Oral Investig 2023; 27:7725-7735. [PMID: 37924358 DOI: 10.1007/s00784-023-05363-x] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/13/2023] [Accepted: 10/23/2023] [Indexed: 11/06/2023]
Abstract
OBJECTIVE This study aimed to evaluate the microbial functional profile of biofilms related to caries-free (CF, n = 6) and caries-arrested (CI, n = 3) compared to caries-active (CA, n = 5) individuals. MATERIALS AND METHODS A metatranscriptomic was performed in supragingival biofilm from different clinical conditions related to caries or health. Total RNA was extracted and cDNAs were obtained and sequenced (Illumina HiSeq3000). Trimmed data (SortMeRNA) were submitted to the SqueezeMeta pipeline in the co-assembly mode for functional analysis and further differential gene expression analysis (DESeq2) and weighted gene co-expression network analysis (WCGNA) to explore and identify gene modules related to these clinical conditions. RESULTS A total of 5303 genes were found in the metatranscriptomic analysis. A co-expression network identified the most relevant modules strongly related to specific caries status. Correlation coefficients were calculated between the eigengene modules and the clinical conditions (CA, CI, and CF) discriminating multiple modules. CA and CI showed weak correlation coefficient strength across the modules, while the CF condition presented a very strong positive correlation coefficient (r = 0.9, p value = 4 × 10-9). Pearson's test was applied to further analyze the module membership and gene significance in CF conditions, and the most relevant were HSPA1s-K03283, Epr- K13277, and SLC1A-K05613. Gene Ontology (GO) shows important bioprocesses, such as two-component system, fructose and mannose metabolism, pentose and glucuronate interconversions, and flagellar assembly (p-adjust < 0.05). The ability to use different carbohydrates, integrate multiple signals, swarm, and bacteriocin production are significant metabolic advantages in the oral environment related to CF. CONCLUSIONS A distinct functional health profile could be found in CF, where co-occurring genes can act in different pathways at the same time. Genes HSPA1s, Epr, and SLC1A may be appointed as potential biomarkers for caries-free biofilms. CLINICAL RELEVANCE Potential biomarkers for caries-free biofilms could contribute to the knowledge of caries prevention and control.
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Affiliation(s)
- Laís Daniela Ev
- Department of Preventive and Social Dentistry, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Joice de Faria Poloni
- School of Health and Life Sciences, Pontifical Catholic University of Rio Grande do Sul, National Institute of Science and Technology - Forensic Science, Porto Alegre, Brazil
| | - Nailê Damé-Teixeira
- Department of Dentistry, Faculty of Health Sciences, University of Brasília, Brasília, DF, Brazil
| | - Rodrigo Alex Arthur
- Department of Preventive and Social Dentistry, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
| | - Daniela Jorge Corralo
- Department of Dentistry, School of Dentistry, Passo Fundo University, Passo Fundo, RS, Brazil
| | - Sandra Liana Henz
- Department of Preventive and Social Dentistry, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil.
| | - Thuy Do
- Division of Oral Biology, School of Dentistry, Faculty of Medicine & Health, University of Leeds, Leeds, UK
| | - Marisa Maltz
- Department of Preventive and Social Dentistry, School of Dentistry, Federal University of Rio Grande do Sul, Porto Alegre, RS, Brazil
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Kies PJ, Hammer ND. A Resourceful Race: Bacterial Scavenging of Host Sulfur Metabolism during Colonization. Infect Immun 2022; 90:e0057921. [PMID: 35315692 PMCID: PMC9119060 DOI: 10.1128/iai.00579-21] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sulfur is a requirement for life. Therefore, both the host and colonizing bacteria must regulate sulfur metabolism in a coordinated fashion to meet cellular demands. The host environment is a rich source of organic and inorganic sulfur metabolites that are utilized in critical physiological processes such as redox homeostasis and cellular signaling. As such, modulating enzymes dedicated to sulfur metabolite biosynthesis plays a vital role in host fitness. This is exemplified from a molecular standpoint through layered regulation of this machinery at the transcriptional, translational, and posttranslational levels. With such a diverse metabolite pool available, pathogens and symbionts have evolved multiple mechanisms to exploit sulfur reservoirs to ensure propagation within the host. Indeed, characterization of sulfur transporters has revealed that bacteria employ multiple tactics to acquire ideal sulfur sources, such as cysteine and its derivatives. However, bacteria that employ acquisition strategies targeting multiple sulfur sources complicate in vivo studies that investigate how specific sulfur metabolites support proliferation. Furthermore, regulatory systems controlling the bacterial sulfur regulon are also multifaceted. This too creates an interesting challenge for in vivo work focused on bacterial regulation of sulfur metabolism in response to the host. This review examines the importance of sulfur at the host-bacterium interface and the elegant studies conducted to define this interaction.
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Affiliation(s)
- Paige J. Kies
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
| | - Neal D. Hammer
- Department of Microbiology and Molecular Genetics, Michigan State University, East Lansing, Michigan, USA
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5
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Reddy KD, Ciftci D, Scopelliti AJ, Boudker O. The archaeal glutamate transporter homologue GltPh shows heterogeneous substrate binding. J Gen Physiol 2022; 154:e202213131. [PMID: 35452090 PMCID: PMC9044058 DOI: 10.1085/jgp.202213131] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2022] [Accepted: 03/10/2022] [Indexed: 12/31/2022] Open
Abstract
Integral membrane glutamate transporters couple the concentrative substrate transport to ion gradients. There is a wealth of structural and mechanistic information about this protein family. Recent studies of an archaeal homologue, GltPh, revealed transport rate heterogeneity, which is inconsistent with simple kinetic models; however, its structural and mechanistic determinants remain undefined. Here, we demonstrate that in a mutant GltPh, which exclusively populates the outward-facing state, at least two substates coexist in slow equilibrium, binding the substrate with different apparent affinities. Wild type GltPh shows similar binding properties, and modulation of the substate equilibrium correlates with transport rates. The low-affinity substate of the mutant is transient following substrate binding. Consistently, cryo-EM on samples frozen within seconds after substrate addition reveals the presence of structural classes with perturbed helical packing of the extracellular half of the transport domain in regions adjacent to the binding site. By contrast, an equilibrated structure does not show such classes. The structure at 2.2-Å resolution details a pattern of waters in the intracellular half of the domain and resolves classes with subtle differences in the substrate-binding site. We hypothesize that the rigid cytoplasmic half of the domain mediates substrate and ion recognition and coupling, whereas the extracellular labile half sets the affinity and dynamic properties.
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Affiliation(s)
- Krishna D. Reddy
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY
| | - Didar Ciftci
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY
- Tri-Institutional Training Program in Chemical Biology, New York, NY
| | | | - Olga Boudker
- Department of Physiology and Biophysics, Weill Cornell Medicine, New York, NY
- Howard Hughes Medical Institute, Weill Cornell Medicine, New York, NY
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6
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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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7
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Bloom SM, Mafunda NA, Woolston BM, Hayward MR, Frempong JF, Abai AB, Xu J, Mitchell AJ, Westergaard X, Hussain FA, Xulu N, Dong M, Dong KL, Gumbi T, Ceasar FX, Rice JK, Choksi N, Ismail N, Ndung'u T, Ghebremichael MS, Relman DA, Balskus EP, Mitchell CM, Kwon DS. Cysteine dependence of Lactobacillus iners is a potential therapeutic target for vaginal microbiota modulation. Nat Microbiol 2022; 7:434-450. [PMID: 35241796 PMCID: PMC10473153 DOI: 10.1038/s41564-022-01070-7] [Citation(s) in RCA: 28] [Impact Index Per Article: 14.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/16/2021] [Accepted: 01/27/2022] [Indexed: 12/28/2022]
Abstract
Vaginal microbiota composition affects many facets of reproductive health. Lactobacillus iners-dominated microbial communities are associated with poorer outcomes, including higher risk of bacterial vaginosis (BV), compared with vaginal microbiota rich in L. crispatus. Unfortunately, standard-of-care metronidazole therapy for BV typically results in dominance of L. iners, probably contributing to post-treatment relapse. Here we generate an L. iners isolate collection comprising 34 previously unreported isolates from 14 South African women with and without BV and 4 previously unreported isolates from 3 US women. We also report an associated genome catalogue comprising 1,218 vaginal Lactobacillus isolate genomes and metagenome-assembled genomes from >300 women across 4 continents. We show that, unlike L. crispatus, L. iners growth is dependent on L-cysteine in vitro and we trace this phenotype to the absence of canonical cysteine biosynthesis pathways and a restricted repertoire of cysteine-related transport mechanisms. We further show that cysteine concentrations in cervicovaginal lavage samples correlate with Lactobacillus abundance in vivo and that cystine uptake inhibitors selectively inhibit L. iners growth in vitro. Combining an inhibitor with metronidazole promotes L. crispatus dominance of defined BV-like communities in vitro by suppressing L. iners growth. Our findings enable a better understanding of L. iners biology and suggest candidate treatments to modulate the vaginal microbiota to improve reproductive health for women globally.
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Affiliation(s)
- Seth M Bloom
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Nomfuneko A Mafunda
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Harvard T.H. Chan School of Public Health, Boston, MA, USA
| | - Benjamin M Woolston
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
- Department of Chemical Engineering, Northeastern University, Boston, MA, USA
| | - Matthew R Hayward
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Josephine F Frempong
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Medical Scientist Training Program, Washington University School of Medicine, St Louis, MO, USA
| | - Aaron B Abai
- Harvard College, Harvard University, Cambridge, MA, USA
| | - Jiawu Xu
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
| | - Alissa J Mitchell
- Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, USA
- William Carey University College of Osteopathic Medicine, Hattiesburg, MS, USA
| | - Xavier Westergaard
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, USA
- Department of Biological Sciences, Columbia University, New York, NY, USA
| | - Fatima A Hussain
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - Nondumiso Xulu
- HIV Pathogenesis Programme (HPP), The Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban, South Africa
| | - Mary Dong
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Massachusetts General Hospital, Boston, MA, USA
| | - Krista L Dong
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA
- Harvard Medical School, Boston, MA, USA
| | | | | | - Justin K Rice
- Harvard Medical School, Boston, MA, USA
- Ronald O. Perelman Department of Emergency Medicine, NYU School of Medicine, New York, NY, USA
| | - Namit Choksi
- Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, USA
- Rishihood University - School of Healthcare, Sonepat, Haryana, India
| | - Nasreen Ismail
- HIV Pathogenesis Programme (HPP), The Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban, South Africa
| | - Thumbi Ndung'u
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- HIV Pathogenesis Programme (HPP), The Doris Duke Medical Research Institute, University of KwaZulu-Natal, Durban, South Africa
- Africa Health Research Institute (AHRI), Durban, South Africa
- Max Planck Institute for Infection Biology, Berlin, Germany
- Division of Infection and Immunity, University College London, London, UK
| | - Musie S Ghebremichael
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Harvard Medical School, Boston, MA, USA
| | - David A Relman
- Department of Microbiology and Immunology, Stanford University School of Medicine, Stanford, CA, USA
- Department of Medicine, Stanford University School of Medicine, Stanford, CA, USA
- Infectious Diseases Section, Veterans Affairs Palo Alto Health Care System, Palo Alto, CA, USA
| | - Emily P Balskus
- Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA
| | - Caroline M Mitchell
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA
- Harvard Medical School, Boston, MA, USA
- Department of Obstetrics and Gynecology, Massachusetts General Hospital, Boston, MA, USA
| | - Douglas S Kwon
- Ragon Institute of MGH, MIT and Harvard, Cambridge, MA, USA.
- Division of Infectious Diseases, Massachusetts General Hospital, Boston, MA, USA.
- Harvard Medical School, Boston, MA, USA.
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8
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Li SW, Wen Y, Leng Y. Transcriptome analysis provides new insights into the tolerance and reduction of Lysinibacillus fusiformis 15-4 to hexavalent chromium. Appl Microbiol Biotechnol 2021; 105:7841-7855. [PMID: 34546405 DOI: 10.1007/s00253-021-11586-3] [Citation(s) in RCA: 6] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/16/2021] [Revised: 08/22/2021] [Accepted: 08/26/2021] [Indexed: 12/13/2022]
Abstract
Microbial bioremediation of Cr(VI)-contaminated environments has drawn extensive concern. However, the molecular processes underlying the microbial Cr(VI) tolerance and reduction remain unclear. We isolated a Cr(VI)-reducing Lysinibacillus fusiformis strain 15-4 from soil on the Qinghai-Tibet Plateau. When grown in 1 mM and 2 mM Cr(VI)-containing medium, strain 15-4 could reduce 100% and 93.7% of Cr(VI) to Cr(III) after 36 h and 60 h of incubation, respectively. To know the molecular processes in response to Cr(VI), transcriptome sequencing was carried out using RNA-Seq technology. The results annotated a total of 3913 expressed genes in the strain. One thousand ninety-eight genes (28.1%) were significantly (fold change ≥ 2, false discovery rate ≤ 0.05) expressed in response to Cr(VI), of which 605 (55.1%) were upregulated and 493 (44.9%) were downregulated. The enrichment analysis showed that a total of 630 differentially expressed genes (DEGs) were enriched to 122 KEGG pathways, of which 8 pathways were significantly (p < 0.05) enriched in Cr(VI)-treated sample, including ATP-binding cassette (ABC) transporters (97 DEGs), ribosome (40), sulfur metabolism (16), aminoacyl-tRNA biosynthesis (19), porphyrin metabolism (20), quorum sensing (44), oxidative phosphorylation (17), and histidine metabolism (10), suggesting that these pathways play key roles to cope with Cr(VI) in the strain. The highly upregulated DEGs consisted of 29 oxidoreductase, 18 dehydrogenase, 14 cell redox homeostasis and stress response protein, and 10 DNA damage and repair protein genes. However, seven Na+:H+ antiporter complex-coding DEGs and most of transcriptional regulator-coding DEGs were significantly downregulated in the Cr-treated sample. Many of FMN/NAD(P)H-dependent reductase-encoding genes were greatly induced by Cr, suggesting the involvement of these genes in Cr(VI) reduction in strain 15-4. Sulfur and iron ions as well as the thiol-disulfide exchange reactions might play synergistic roles in Cr reduction.Key points• Lysinibacillus fusiformis 15-4 was able to tolerate and reduce Cr(VI) to Cr(III).• Transcriptome analysis revealed that 1098 DEGs and 8 key KEGG pathways significantly responded to Cr(VI).• Sulfur metabolism, protein biosynthesis, and porphyrin metabolism were the key pathways associated with the survival of strain 15-4 in response to Cr(VI).
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Affiliation(s)
- Shi-Weng Li
- School of Environmental and Municipal Engineering, Lanzhou Jiaotong University, Lanzhou, People's Republic of China. .,School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China. .,Key Laboratory of Extreme Environmental Microbial Resources and Engineering in Gansu Province, Lanzhou, 730000, People's Republic of China.
| | - Ya Wen
- School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
| | - Yan Leng
- School of Chemical and Biological Engineering, Lanzhou Jiaotong University, Lanzhou, 730070, People's Republic of China
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9
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Rytter H, Jamet A, Ziveri J, Ramond E, Coureuil M, Lagouge-Roussey P, Euphrasie D, Tros F, Goudin N, Chhuon C, Nemazanyy I, de Moraes FE, Labate C, Guerrera IC, Charbit A. The pentose phosphate pathway constitutes a major metabolic hub in pathogenic Francisella. PLoS Pathog 2021; 17:e1009326. [PMID: 34339477 PMCID: PMC8360588 DOI: 10.1371/journal.ppat.1009326] [Citation(s) in RCA: 16] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2021] [Revised: 08/12/2021] [Accepted: 07/14/2021] [Indexed: 11/19/2022] Open
Abstract
Metabolic pathways are now considered as intrinsic virulence attributes of pathogenic bacteria and thus represent potential targets for antibacterial strategies. Here we focused on the role of the pentose phosphate pathway (PPP) and its connections with other metabolic pathways in the pathophysiology of Francisella novicida. The involvement of the PPP in the intracellular life cycle of Francisella was first demonstrated by studying PPP inactivating mutants. Indeed, we observed that inactivation of the tktA, rpiA or rpe genes severely impaired intramacrophage multiplication during the first 24 hours. However, time-lapse video microscopy demonstrated that rpiA and rpe mutants were able to resume late intracellular multiplication. To better understand the links between PPP and other metabolic networks in the bacterium, we also performed an extensive proteo-metabolomic analysis of these mutants. We show that the PPP constitutes a major bacterial metabolic hub with multiple connections to glycolysis, the tricarboxylic acid cycle and other pathways, such as fatty acid degradation and sulfur metabolism. Altogether our study highlights how PPP plays a key role in the pathogenesis and growth of Francisella in its intracellular niche.
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Affiliation(s)
- Héloise Rytter
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
| | - Anne Jamet
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
| | - Jason Ziveri
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
| | - Elodie Ramond
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
| | - Mathieu Coureuil
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
| | - Pauline Lagouge-Roussey
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
| | - Daniel Euphrasie
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
| | - Fabiola Tros
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
| | - Nicolas Goudin
- Pole Bio-analyse d’images, Structure Fédérative de Recherche Necker INSERM US24- CNRS UMS 3633, Paris, France
| | - Cerina Chhuon
- Université de Paris, Paris, France
- Plateforme Protéome Institut Necker, PPN, Structure Fédérative de Recherche Necker INSERM US24-CNRS UMS 3633, Paris, France
| | - Ivan Nemazanyy
- Université de Paris, Paris, France
- Plateforme Etude du métabolisme, Structure Fédérative de Recherche Necker INSERM US24-CNRS UMS 3633, Paris, France
| | - Fabricio Edgar de Moraes
- Laboratório Max Feffer de Genética de Plantas, Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, Brazil
| | - Carlos Labate
- Laboratório Max Feffer de Genética de Plantas, Departamento de Genética, Escola Superior de Agricultura Luiz de Queiroz, Universidade de São Paulo, Piracicaba, Brazil
| | - Ida Chiara Guerrera
- Université de Paris, Paris, France
- Plateforme Protéome Institut Necker, PPN, Structure Fédérative de Recherche Necker INSERM US24-CNRS UMS 3633, Paris, France
- * E-mail: (ICG); (AC)
| | - Alain Charbit
- Université de Paris, Paris, France
- INSERM U1151 - CNRS UMR 8253, Institut Necker-Enfants Malades. Team 7: Pathogénie des Infections Systémiques, Paris, France
- * E-mail: (ICG); (AC)
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10
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Pipatthana M, Harnvoravongchai P, Pongchaikul P, Likhitrattanapisal S, Phanchana M, Chankhamhaengdecha S, Janvilisri T. The repertoire of ABC proteins in Clostridioides difficile. Comput Struct Biotechnol J 2021; 19:2905-2920. [PMID: 34094001 PMCID: PMC8144104 DOI: 10.1016/j.csbj.2021.05.012] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/14/2021] [Revised: 05/02/2021] [Accepted: 05/05/2021] [Indexed: 11/07/2022] Open
Abstract
ABC transporters transport substrates across membranes driven by ATP hydrolysis. ABC proteins of C. difficile 630 can be classified into 12 sub-families. Most NPs are found within sub-families involving in drug export. Most core NPs in C. difficile are associated with drug efflux system. ABC proteins in sub-families 3, 6, 7, and 9 may participate in drug resistance.
ATP-binding cassette (ABC) transporters belong to one of the largest membrane protein superfamilies, which function in translocating substrates across biological membranes using energy from ATP hydrolysis. Currently, the classification of ABC transporters in Clostridioides difficile is not complete. Therefore, the sequence-function relationship of all ABC proteins encoded within the C. difficile genome was analyzed. Identification of protein domains associated with the ABC system in the C. difficile 630 reference genome revealed 226 domains: 97 nucleotide-binding domains (NBDs), 98 transmembrane domains (TMDs), 30 substrate-binding domains (SBDs), and one domain with features of an adaptor protein. Gene organization and transcriptional unit analyses indicated the presence of 78 ABC systems comprising 28 importers and 50 exporters. Based on NBD sequence similarity, ABC transporters were classified into 12 sub-families according to their substrates. Interestingly, all ABC exporters, accounting for 64% of the total ABC systems, are involved in antibiotic resistance. Based on analysis of ABC proteins from 49 C. difficile strains, the majority of core NBDs are predicted to be involved in multidrug resistance systems, consistent with the ability of this organism to survive exposure to an array of antibiotics. Our findings herein provide another step toward a better understanding of the function and evolutionary relationships of ABC proteins in this pathogen.
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Affiliation(s)
- Methinee Pipatthana
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
| | | | - Pisut Pongchaikul
- Chakri Naruebodindra Medical Institute, Faculty of Medicine Ramathibodi Hospital, Mahidol University, Samut Prakarn, Thailand
| | - Somsak Likhitrattanapisal
- Thailand Bioresource Research Center (TBRC), National Center for Genetic Engineering and Biotechnology (BIOTEC), National Science and Technology Development Agency (NSTDA), Pathumthani, Thailand
| | - Matthew Phanchana
- Department of Molecular Tropical Medicine and Genetics, Faculty of Tropical Medicine, Mahidol University, Bangkok, Thailand
| | | | - Tavan Janvilisri
- Department of Biochemistry, Faculty of Science, Mahidol University, Bangkok, Thailand
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11
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Man L, Dale AL, Klare WP, Cain JA, Sumer-Bayraktar Z, Niewold P, Solis N, Cordwell SJ. Proteomics of Campylobacter jejuni Growth in Deoxycholate Reveals Cj0025c as a Cystine Transport Protein Required for Wild-type Human Infection Phenotypes. Mol Cell Proteomics 2020; 19:1263-1280. [PMID: 32376616 PMCID: PMC8015009 DOI: 10.1074/mcp.ra120.002029] [Citation(s) in RCA: 8] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/09/2020] [Revised: 05/01/2020] [Indexed: 12/12/2022] Open
Abstract
Campylobacter jejuni is a major cause of food-borne gastroenteritis. Proteomics by label-based two-dimensional liquid chromatography coupled to tandem mass spectrometry (LC-MS/MS) identified proteins associated with growth in 0.1% sodium deoxycholate (DOC, a component of gut bile salts), and system-wide validation was performed by data-independent acquisition (DIA-SWATH-MS). LC-MS/MS quantified 1326 proteins (∼82% of the predicted C. jejuni proteome), of which 1104 were validated in additional biological replicates by DIA-SWATH-MS. DOC resulted in a profound proteome shift with 512 proteins showing significantly altered abundance. Induced proteins were associated with flagellar motility and antibiotic resistance; and these correlated with increased DOC motility and resistance to polymyxin B and ciprofloxacin. DOC also increased human Caco-2 cell adherence and invasion. Abundances of proteins involved in nutrient transport were altered by DOC and aligned with intracellular changes to their respective carbon sources. DOC increased intracellular levels of sulfur-containing amino acids (cysteine and methionine) and the dipeptide cystine (Cys-Cys), which also correlated with reduced resistance to oxidative stress. A DOC induced transport protein was Cj0025c, which has sequence similarity to bacterial Cys-Cys transporters. Deletion of cj0025c (Δcj0025c) resulted in proteome changes consistent with sulfur starvation, as well as attenuated invasion, reduced motility, atypical morphology, increased antimicrobial susceptibility and poor biofilm formation. Targeted metabolomics showed Δcj0025c could use known C. jejuni amino and organic acid substrates commensurate with wild-type. Medium Cys-Cys levels however, were maintained in Δcj0025c relative to wild-type. A toxic Cys-Cys mimic (selenocystine) inhibited wild-type growth, but not Δcj0025c Provision of an alternate sulfur source (2 mm thiosulfate) restored Δcj0025c motility. Our data confirm that Cj0025c is a Cys-Cys transporter that we have named TcyP consistent with the nomenclature of homologous proteins in other species.
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Affiliation(s)
- Lok Man
- School of Life and Environmental Sciences, The University of Sydney, Australia; Charles Perkins Centre, The University of Sydney, Australia
| | - Ashleigh L Dale
- School of Life and Environmental Sciences, The University of Sydney, Australia; Charles Perkins Centre, The University of Sydney, Australia
| | - William P Klare
- School of Life and Environmental Sciences, The University of Sydney, Australia; Charles Perkins Centre, The University of Sydney, Australia
| | - Joel A Cain
- School of Life and Environmental Sciences, The University of Sydney, Australia; Charles Perkins Centre, The University of Sydney, Australia
| | - Zeynep Sumer-Bayraktar
- School of Life and Environmental Sciences, The University of Sydney, Australia; Charles Perkins Centre, The University of Sydney, Australia
| | - Paula Niewold
- Charles Perkins Centre, The University of Sydney, Australia; Discipline of Pathology, School of Medical Sciences, The University of Sydney, Australia
| | - Nestor Solis
- School of Life and Environmental Sciences, The University of Sydney, Australia
| | - Stuart J Cordwell
- School of Life and Environmental Sciences, The University of Sydney, Australia; Charles Perkins Centre, The University of Sydney, Australia; Discipline of Pathology, School of Medical Sciences, The University of Sydney, Australia; Sydney Mass Spectrometry, The University of Sydney, Australia.
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12
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Yamazaki S, Ziyatdinov MK, Nonaka G. Fermentative production of sulfur-containing amino acid with engineering putative l-cystathionine and l-cysteine uptake systems in Escherichia coli. J Biosci Bioeng 2020; 130:14-19. [PMID: 32217026 DOI: 10.1016/j.jbiosc.2020.02.007] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2019] [Revised: 01/18/2020] [Accepted: 02/06/2020] [Indexed: 11/25/2022]
Abstract
Here, proteins involved in sulfur-containing amino acid uptake in Escherichia coli strains were investigated with the aim of applying the findings in fermentative amino acid production. A search of genes in an l-methionine auxotrophic strain library suggested YecSC as the putative transporter of l-cystathionine. l-Methionine production increased by 15% after amplification of yecSC in producer strains. A candidate protein responsible for l-cysteine uptake was also found by experimentation with multicopy suppressor E. coli strains that recovered from growth defects caused by l-cysteine auxotrophy. Based on the results of an uptake assay, growth using l-cysteine as a sole sulfur source, and sensitivity to l-cysteine toxicity, we proposed that YeaN is an l-cysteine transporter. l-Cysteine production increased by 50% as a result of disrupting yeaN in producer strain. The study of amino acid transporters is valuable to industrialized amino acid production and also sheds light on the role of these transporters in sulfur assimilation.
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Affiliation(s)
- Shunsuke Yamazaki
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki, Kanagawa 210-8681, Japan
| | - Mikhail Kharisovich Ziyatdinov
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki, Kanagawa 210-8681, Japan; Ajinomoto-Genetika Research Institute, 117545 Moscow, Russia
| | - Gen Nonaka
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki, Kanagawa 210-8681, Japan; Ajinomoto-Genetika Research Institute, 117545 Moscow, Russia.
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13
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The Staphylococcus aureus Cystine Transporters TcyABC and TcyP Facilitate Nutrient Sulfur Acquisition during Infection. Infect Immun 2020; 88:IAI.00690-19. [PMID: 31843961 DOI: 10.1128/iai.00690-19] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/31/2019] [Accepted: 12/06/2019] [Indexed: 12/21/2022] Open
Abstract
Staphylococcus aureus is a significant human pathogen due to its capacity to cause a multitude of diseases. As such, S. aureus efficiently pillages vital nutrients from the host; however, the molecular mechanisms that support sulfur acquisition during infection have not been established. One of the most abundant extracellular sulfur-containing metabolites within the host is cysteine, which acts as the major redox buffer in the blood by transitioning between reduced and oxidized (cystine) forms. We therefore hypothesized that S. aureus acquires host-derived cysteine and cystine as sources of nutrient sulfur during systemic infection. To test this hypothesis, we used the toxic cystine analogue selenocystine to initially characterize S. aureus homologues of the Bacillus subtilis cystine transporters TcyABC and TcyP. We found that genetic inactivation of both TcyA and TcyP induced selenocystine resistance. The double mutant also failed to proliferate in medium supplemented with cystine, cysteine, or N-acetyl cysteine as the sole sulfur source. However, only TcyABC was necessary for proliferation in defined medium containing homocystine as the sulfur source. Using a murine model of systemic infection, we observed tcyP-dependent competitive defects in the liver and heart, indicating that this sulfur acquisition strategy supports proliferation of S. aureus in these organs. Phylogenetic analyses identified TcyP homologues in many pathogenic species, implying that this sulfur procurement strategy is conserved. In total, this study is the first to experimentally validate sulfur acquisition systems in S. aureus and establish their importance during pathogenesis.
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14
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Choo K, Kim M, Nansa SA, Bae MK, Lee C, Lee SJ. Redox potential change by the cystine importer affected on enzymatic antioxidant protection in Deinococcus geothermalis. Antonie van Leeuwenhoek 2020; 113:779-790. [PMID: 31993844 DOI: 10.1007/s10482-020-01388-4] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/03/2019] [Accepted: 01/21/2020] [Indexed: 10/25/2022]
Abstract
Radiation resistant bacteria genus Deinococcus species were well studied on DNA repair and anti-oxidative stress response mechanisms. There are many protection factors as enzymatic and nonenzymatic involved. One of them is intracellular redox potential as like thiol compounds including cysteine acts as primary protectant against oxidation stress. A gene cluster consisting of the genes Dgeo_1986 and Dgeo_1987 of Deinococcus geothermalis was identified as a cystine importer. The expression levels of dgeo_1986 and dgeo_1987 were up-regulated by over 60-fold and 4-fold during the late exponential (L) growth phase, respectively. The double-knockout mutant of dgeo_1986 and dgeo_1987 was reduced in cystine and thiol concentrations and leading to enhanced sensitivity against H2O2 stress. The expression of catalase (Dgeo_2728) as an enzymatic anti-oxidant is more induced in the wild-type strain than the Δdgeo_1986-87 strain at the late growth phase. The expression level of the oxidative stress response regulator OxyR (Dgeo_1888) is dependent on the intracellular redox balance. That is, when the intracellular thiol content was reduced in the wild-type strain during the L phase, OxyR was clearly induced. Interestingly, the expression level of OxyR was higher in the Δdgeo_1986-87 strain than in the wild-type strain upon H2O2 treatment. Although OxyR was induced by H2O2 treatment in Δdgeo_1986-87 strain, where intracellular redox potential of cystine was reduced as a thiol compound due to reduced cystine import, the relative level of expression of catalase was unexpectedly down-regulated. Therefore, the catalase induction system as an enzymatic antioxidant protection should be affected via the cystine importer but not rely on the OxyR controlled manner.
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Affiliation(s)
- Kyungsil Choo
- Department of Biology, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, Korea
| | - Minwook Kim
- Department of Biology, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, Korea.,Department of Developmental Biology, Pittsburgh Liver Research Center, McGowan Institute for Regenerative Medicine, University of Pittsburgh, Pittsburgh, PA, 15260, USA
| | - Sama Abdi Nansa
- Department of Biology, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, Korea
| | - Min K Bae
- Department of Biology, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, Korea
| | - Chanjae Lee
- Department of Biology, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, Korea
| | - Sung-Jae Lee
- Department of Biology, Kyung Hee University, 26 Kyungheedae-ro, Dongdaemun-gu, Seoul, 02447, Korea.
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15
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Kumar P, Kesari P, Kokane S, Ghosh DK, Kumar P, Sharma AK. Crystal structures of a putative periplasmic cystine-binding protein from Candidatus Liberibacter asiaticus: insights into an adapted mechanism of ligand binding. FEBS J 2019; 286:3450-3472. [PMID: 31063259 DOI: 10.1111/febs.14921] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/25/2019] [Revised: 03/20/2019] [Accepted: 05/03/2019] [Indexed: 11/28/2022]
Abstract
The amino acid-binding receptors, a component of ABC transporters, have evolved to cater to different specificities and functions. Of particular interest are cystine-binding receptors, which have shown broad specificity. In the present study, a putative periplasmic cystine-binding protein from Candidatus Liberibacter asiaticus (CLasTcyA) was characterized. Analysis of the CLasTcyA sequence and crystal structures in the ligand-bound state revealed novel features of CLasTcyA in comparison to related proteins. One of the unique features found in CLasTcyA structure was the positioning of the C-terminal extended loop of one chain very close to the substrate-binding site of the adjacent monomer in the asymmetric unit. The presence of a disulphide bond, unique to Candidatus Liberibacter family, holds the C-terminal extended loop in position. Analysis of the substrate-binding pocket of CLasTcyA suggested a broad specificity and a completely different orientation of the bound substrates in comparison to related protein structures. The open conformation for one of the two chains of the asymmetric unit in the Arg-bound structure revealed a limited open state (18.4°) for CLasTcyA as compared to open state of other related proteins (~ 60°). The strong interaction between Asp126 on helix-α5 of small domain and Arg82 (bigger domain) restricts the degree of opening in ligand-free open state. The dissociation constant of 1.26 μm by SPR and 3.7 μm by MST exhibited low affinity for the cystine. This is the first structural characterization of an l-cystine ABC transporter from plant pathogen and our results suggest that CLasTcyA may have evolved to cater to its specific needs for its survival in the host.
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Affiliation(s)
- Pranav Kumar
- Department of Biotechnology, Indian Institute of Technology Roorkee, India
| | - Pooja Kesari
- Department of Biotechnology, Indian Institute of Technology Roorkee, India
| | - Sunil Kokane
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur, India
| | - Dilip Kumar Ghosh
- Plant Virology Laboratory, ICAR-Central Citrus Research Institute, Nagpur, India
| | - Pravindra Kumar
- Department of Biotechnology, Indian Institute of Technology Roorkee, India
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16
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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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17
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Lensmire JM, Hammer ND. Nutrient sulfur acquisition strategies employed by bacterial pathogens. Curr Opin Microbiol 2019; 47:52-58. [DOI: 10.1016/j.mib.2018.11.002] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/29/2018] [Revised: 11/04/2018] [Accepted: 11/07/2018] [Indexed: 10/27/2022]
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18
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Emerging nano-biosensing with suspended MNP microbial extraction and EANP labeling. Biosens Bioelectron 2018; 117:781-793. [PMID: 30029200 DOI: 10.1016/j.bios.2018.07.007] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/17/2018] [Revised: 07/02/2018] [Accepted: 07/05/2018] [Indexed: 02/08/2023]
Abstract
Emerging nano-biosensing with suspended MNP microbial extraction and EANP labeling may ensure a secure microbe-free food supply, as rapid response detection of microbial contamination is of utmost importance. Many biosensor designs have been proposed over the past two decades, covering a broad range of binding ligands, signal amplification, and detection mechanisms. These designs may consist of self-contained test strips developed from the base up with complicated nanoparticle chemistry and intricate ligand immobilization. Other methods use multiple step-wise additions, many based upon ELISA 96-well plate technology with fluorescent detection. In addition, many biosensors use expensive antibody receptors or DNA ligands. But many of these proposed designs are impracticable for most applications or users, since they don't FIRST address the broad goals of any biosensor: Field operability, Inexpensive, with Real-time detection that is both Sensitive and Specific to target, while being as Trouble-free as possible. Described in this review are applications that utilize versatile magnetic nanoparticles (MNP) extraction, electrically active nanoparticles (EANP) labeling, and carbohydrate-based ligand chemistry. MNP provide rapid pathogen extraction from liquid samples. EANP labeling improves signal amplification and expands signaling options to include optical and electrical detection. Carbohydrate ligands are inexpensive, robust structures that are increasingly synthesized for higher selectivity. Used in conjunction with optical or electrical detection of gold nanoparticles (AuNP), carbohydrate-functionalized MNP-cell-AuNP nano-biosensing advances the goal of being the FIRST biosensor of choice in detecting microbial pathogens throughout our food supply chain.
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19
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Zhao H, Roistacher DM, Helmann JD. Aspartate deficiency limits peptidoglycan synthesis and sensitizes cells to antibiotics targeting cell wall synthesis in Bacillus subtilis. Mol Microbiol 2018; 109:826-844. [PMID: 29995990 DOI: 10.1111/mmi.14078] [Citation(s) in RCA: 25] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/07/2018] [Revised: 07/02/2018] [Accepted: 07/05/2018] [Indexed: 12/31/2022]
Abstract
Peptidoglycan synthesis is an important target for antibiotics and relies on intermediates derived from central metabolism. As a result, alterations of metabolism may affect antibiotic sensitivity. An aspB mutant is auxotrophic for aspartate (Asp) and asparagine (Asn) and lyses when grown in Difco sporulation medium (DSM), but not in LB medium. Genetic and physiological studies, supported by amino acid analysis, reveal that cell lysis in DSM results from Asp limitation due to a relatively low Asp and high glutamate (Glu) concentrations, with Glu functioning as a competitive inhibitor of Asp uptake by the major Glu/Asp transporter GltT. Lysis can be specifically suppressed by supplementation with 2,6-diaminopimelate (DAP), which is imported by two different cystine uptake systems. These studies suggest that aspartate limitation depletes the peptidoglycan precursor meso-2,6-diaminopimelate (mDAP), inhibits peptidoglycan synthesis, upregulates the cell envelope stress response mediated by σM and eventually leads to cell lysis. Aspartate limitation sensitizes cells to antibiotics targeting late steps of PG synthesis, but not steps prior to the addition of mDAP into the pentapeptide sidechain. This work highlights the ability of perturbations of central metabolism to sensitize cells to peptidoglycan synthesis inhibitors.
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Affiliation(s)
- Heng Zhao
- Department of Microbiology, Cornell University, Ithaca, NY, USA
| | | | - John D Helmann
- Department of Microbiology, Cornell University, Ithaca, NY, USA
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20
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Gu H, Shi K, Liao Z, Qi H, Chen S, Wang H, Li S, Ma Y, Wang J. Time-resolved transcriptome analysis of Clostridium difficile R20291 response to cysteine. Microbiol Res 2018; 215:114-125. [PMID: 30172297 DOI: 10.1016/j.micres.2018.07.003] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/28/2018] [Revised: 05/21/2018] [Accepted: 07/07/2018] [Indexed: 01/05/2023]
Abstract
The incidence of Clostridium difficile infection has been steadily rising over the past decade. The increase in the rate of incidence is associated with the specific NAP1/BI/027 strains which are "hypervirulent" and have led to several large outbreaks since their emergence. However, the relation between these outbreaks and virulence regulation mechanisms remains unclear. It has been reported that the major virulence factor TcdA and TcdB in C. difficile could be repressed by cysteine. Here, we investigated the functional and virulence-associated regulation of C. difficile R20291 response to cysteine by using a time-resolved genome-wide transcriptome analysis. Dramatic changes of gene expression in C. difficile revealed functional processes related to transport, metabolism, and regulators in the presence of cysteine during different phases of growth. Flagellar and ribosomal genes were significantly down-regulated in long-term response to cysteine. Many NAP1/BI/027- specific genes were also modulated by cysteine. In addition, cdsB inactivation in C. difficile R20291 could remove the repression of toxin synthesis but could not remove the repression of butyrate production in the presence of cysteine. This suggests that toxin synthesis and butyrate production might have different regulatory controls in response to cysteine. Altogether, our research provides important insights into the regulatory mechanisms of C. difficile response to cysteine.
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Affiliation(s)
- Huawei Gu
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Kan Shi
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Zhengping Liao
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Haonan Qi
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Shuyi Chen
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Haiying Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Shan Li
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Yi Ma
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China
| | - Jufang Wang
- School of Biology and Biological Engineering, South China University of Technology, Guangzhou, China.
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21
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Ernst DC, Christopherson MR, Downs DM. Increased Activity of Cystathionine β-Lyase Suppresses 2-Aminoacrylate Stress in Salmonella enterica. J Bacteriol 2018; 200:e00040-18. [PMID: 29440255 PMCID: PMC5892115 DOI: 10.1128/jb.00040-18] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/29/2018] [Accepted: 02/08/2018] [Indexed: 01/07/2023] Open
Abstract
Reactive enamine stress caused by intracellular 2-aminoacrylate accumulation leads to pleiotropic growth defects in a variety of organisms. Members of the well-conserved RidA/YER057c/UK114 protein family prevent enamine stress by enhancing the breakdown of 2-aminoacrylate to pyruvate. In Salmonella enterica, disruption of RidA allows 2-aminoacrylate to accumulate and to inactivate a variety of pyridoxal 5'-phosphate-dependent enzymes by generating covalent bonds with the enzyme and/or cofactor. This study was initiated to identify mechanisms that can overcome 2-aminoacrylate stress in the absence of RidA. Multicopy suppressor analysis revealed that overproduction of the methionine biosynthesis enzyme cystathionine β-lyase (MetC) (EC 4.4.1.8) alleviated the pleiotropic consequences of 2-aminoacrylate stress in a ridA mutant strain. Degradation of cystathionine by MetC was not required for suppression of ridA phenotypes. The data support a model in which MetC acts on a noncystathionine substrate to generate a metabolite that reduces 2-aminoacrylate levels, representing a nonenzymatic mechanism of 2-aminoacrylate depletion.IMPORTANCE RidA proteins are broadly conserved and have been demonstrated to deaminate 2-aminoacrylate and other enamines. 2-Aminoacrylate is generated as an obligatory intermediate in several pyridoxal 5'-phosphate-dependent reactions; if it accumulates, it damages cellular enzymes. This study identified a novel mechanism to eliminate 2-aminoacrylate stress that required the overproduction, but not the canonical activity, of cystathionine β-lyase. The data suggest that a metabolite-metabolite interaction is responsible for quenching 2-aminoacrylate, and they emphasize the need for emerging technologies to probe metabolism in vivo.
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Affiliation(s)
- Dustin C Ernst
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
| | | | - Diana M Downs
- Department of Microbiology, University of Georgia, Athens, Georgia, USA
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22
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Abstract
SIGNIFICANCE Since the discovery and structural characterization of bacillithiol (BSH), the biochemical functions of BSH-biosynthesis enzymes (BshA/B/C) and BSH-dependent detoxification enzymes (FosB, Bst, GlxA/B) have been explored in Bacillus and Staphylococcus species. It was shown that BSH plays an important role in detoxification of reactive oxygen and electrophilic species, alkylating agents, toxins, and antibiotics. Recent Advances: More recently, new functions of BSH were discovered in metal homeostasis (Zn buffering, Fe-sulfur cluster, and copper homeostasis) and virulence control in Staphylococcus aureus. Unexpectedly, strains of the S. aureus NCTC8325 lineage were identified as natural BSH-deficient mutants. Modern mass spectrometry-based approaches have revealed the global reach of protein S-bacillithiolation in Firmicutes as an important regulatory redox modification under hypochlorite stress. S-bacillithiolation of OhrR, MetE, and glyceraldehyde-3-phosphate dehydrogenase (Gap) functions, analogous to S-glutathionylation, as both a redox-regulatory device and in thiol protection under oxidative stress. CRITICAL ISSUES Although the functions of the bacilliredoxin (Brx) pathways in the reversal of S-bacillithiolations have been recently addressed, significantly more work is needed to establish the complete Brx reduction pathway, including the major enzyme(s), for reduction of oxidized BSH (BSSB) and the targets of Brx action in vivo. FUTURE DIRECTIONS Despite the large number of identified S-bacillithiolated proteins, the physiological relevance of this redox modification was shown for only selected targets and should be a subject of future studies. In addition, many more BSH-dependent detoxification enzymes are evident from previous studies, although their roles and biochemical mechanisms require further study. This review of BSH research also pin-points these missing gaps for future research. Antioxid. Redox Signal. 28, 445-462.
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Affiliation(s)
- Pete Chandrangsu
- 1 Department of Microbiology, Cornell University , Ithaca, New York
| | - Vu Van Loi
- 2 Institute for Biology-Microbiology , Freie Universität Berlin, Berlin, Germany
| | - Haike Antelmann
- 2 Institute for Biology-Microbiology , Freie Universität Berlin, Berlin, Germany
| | - John D Helmann
- 1 Department of Microbiology, Cornell University , Ithaca, New York
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Transcriptomic profiles of Clostridium ljungdahlii during lithotrophic growth with syngas or H 2 and CO 2 compared to organotrophic growth with fructose. Sci Rep 2017; 7:13135. [PMID: 29030620 PMCID: PMC5640608 DOI: 10.1038/s41598-017-12712-w] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [Abstract] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2017] [Accepted: 09/14/2017] [Indexed: 01/13/2023] Open
Abstract
Clostridium ljungdahlii derives energy by lithotrophic and organotrophic acetogenesis. C. ljungdahlii was grown organotrophically with fructose and also lithotrophically, either with syngas - a gas mixture containing hydrogen (H2), carbon dioxide (CO2), and carbon monoxide (CO), or with H2 and CO2. Gene expression was compared quantitatively by microarrays using RNA extracted from all three conditions. Gene expression with fructose and with H2/CO2 was compared by RNA-Seq. Upregulated genes with both syngas and H2/CO2 (compared to fructose) point to the urea cycle, uptake and degradation of peptides and amino acids, response to sulfur starvation, potentially NADPH-producing pathways involving (S)-malate and ornithine, quorum sensing, sporulation, and cell wall remodeling, suggesting a global and multicellular response to lithotrophic conditions. With syngas, the upregulated (R)-lactate dehydrogenase gene represents a route of electron transfer from ferredoxin to NAD. With H2/CO2, flavodoxin and histidine biosynthesis genes were upregulated. Downregulated genes corresponded to an intracytoplasmic microcompartment for disposal of methylglyoxal, a toxic byproduct of glycolysis, as 1-propanol. Several cytoplasmic and membrane-associated redox-active protein genes were differentially regulated. The transcriptomic profiles of C. ljungdahlii in lithotrophic and organotrophic growth modes indicate large-scale physiological and metabolic differences, observations that may guide biofuel and commodity chemical production with this species.
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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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Liu YR, Lu X, Zhao L, An J, He JZ, Pierce EM, Johs A, Gu B. Effects of Cellular Sorption on Mercury Bioavailability and Methylmercury Production by Desulfovibrio desulfuricans ND132. ENVIRONMENTAL SCIENCE & TECHNOLOGY 2016; 50:13335-13341. [PMID: 27993064 DOI: 10.1021/acs.est.6b04041] [Citation(s) in RCA: 62] [Impact Index Per Article: 7.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Microbial conversion of inorganic mercury (IHg) to methylmercury (MeHg) is a significant environmental concern because of the bioaccumulation and biomagnification of toxic MeHg in the food web. Laboratory incubation studies have shown that, despite the presence of large quantities of IHg in cell cultures, MeHg biosynthesis often reaches a plateau or a maximum within hours or a day by an as yet unexplained mechanism. Here we report that mercuric Hg(II) can be taken up rapidly by cells of Desulfovibrio desulfuricans ND132, but a large fraction of the Hg(II) is unavailable for methylation because of strong cellular sorption. Thiols, such as cysteine, glutathione, and penicillamine, added either simultaneously with Hg(II) or after cells have been exposed to Hg(II), effectively desorb or mobilize the bound Hg(II), leading to a substantial increase in MeHg production. The amount of thiol-desorbed Hg(II) is strongly correlated to the amount of MeHg produced (r = 0.98). However, cells do not preferentially take up Hg(II)-thiol complexes, but Hg(II)-ligand exchange between these complexes and the cell-associated proteins likely constrains Hg(II) uptake and methylation. We suggest that, aside from aqueous chemical speciation of Hg(II), binding and exchange of Hg(II) between cells and complexing ligands such as thiols and naturally dissolved organics in solution is an important controlling mechanism of Hg(II) bioavailability, which should be considered when predicting MeHg production in the environment.
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Affiliation(s)
- Yu-Rong Liu
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Xia Lu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Linduo Zhao
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Jing An
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Ji-Zheng He
- State Key Laboratory of Urban and Regional Ecology, Research Center for Eco-Environmental Sciences, Chinese Academy of Sciences , Beijing 100085, China
- Department of Veterinary and Agricultural Sciences, the University of Melbourne , Melbourne, Victoria 3010, Australia
| | - Eric M Pierce
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Alexander Johs
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
| | - Baohua Gu
- Environmental Sciences Division, Oak Ridge National Laboratory, Oak Ridge, Tennessee 37831, United States
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Yamazaki S, Takei K, Nonaka G. ydjN encodes an S-sulfocysteine transporter required by Escherichia coli for growth on S-sulfocysteine as a sulfur source. FEMS Microbiol Lett 2016; 363:fnw185. [PMID: 27481704 DOI: 10.1093/femsle/fnw185] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 07/27/2016] [Indexed: 11/13/2022] Open
Abstract
Sulfur is an essential element for growth and many physiological functions. As sulfur sources for Escherichia coli and related bacteria, specific transporters import various sulfur-containing compounds from the environment. In this study, we identified and characterized an alternative function of the cystine transporter YdjN in E. coli as a transporter of S-sulfocysteine, a sulfur-containing intermediate in the assimilatory cysteine biosynthesis that is used as a sulfur source for the growth of E. coli We also demonstrated that the transport of S-sulfocysteine via YdjN depends on the transcriptional regulator CysB, a master regulator that controls most of the genes involved in sulfur assimilation and cysteine metabolism. We found that the use of S-sulfocysteine as a sulfur source depends on glutathione because mutations in glutathione biosynthetic genes abolish growth when S-sulfocysteine is used as a sole sulfur source, thereby supporting the previous findings that the conversion of S-sulfocysteine to cysteine is catalyzed by glutaredoxins. To the best of our knowledge, this is the first report of a functional S-sulfocysteine transporter across organisms, which strongly supports the hypothesis that S-sulfocysteine is not only a metabolic intermediate but also a physiologically significant substance in specific natural environments.
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Affiliation(s)
- Shunsuke Yamazaki
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki, Kanagawa 210-8681, Japan
| | - Kensuke Takei
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki, Kanagawa 210-8681, Japan
| | - Gen Nonaka
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Co., Inc., 1-1 Suzuki-cho, Kawasaki-ku, Kawasaki, Kanagawa 210-8681, Japan
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Control of Clostridium difficile Physiopathology in Response to Cysteine Availability. Infect Immun 2016; 84:2389-405. [PMID: 27297391 DOI: 10.1128/iai.00121-16] [Citation(s) in RCA: 53] [Impact Index Per Article: 6.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/10/2016] [Accepted: 05/31/2016] [Indexed: 11/20/2022] Open
Abstract
The pathogenicity of Clostridium difficile is linked to its ability to produce two toxins: TcdA and TcdB. The level of toxin synthesis is influenced by environmental signals, such as phosphotransferase system (PTS) sugars, biotin, and amino acids, especially cysteine. To understand the molecular mechanisms of cysteine-dependent repression of toxin production, we reconstructed the sulfur metabolism pathways of C. difficile strain 630 in silico and validated some of them by testing C. difficile growth in the presence of various sulfur sources. High levels of sulfide and pyruvate were produced in the presence of 10 mM cysteine, indicating that cysteine is actively catabolized by cysteine desulfhydrases. Using a transcriptomic approach, we analyzed cysteine-dependent control of gene expression and showed that cysteine modulates the expression of genes involved in cysteine metabolism, amino acid biosynthesis, fermentation, energy metabolism, iron acquisition, and the stress response. Additionally, a sigma factor (SigL) and global regulators (CcpA, CodY, and Fur) were tested to elucidate their roles in the cysteine-dependent regulation of toxin production. Among these regulators, only sigL inactivation resulted in the derepression of toxin gene expression in the presence of cysteine. Interestingly, the sigL mutant produced less pyruvate and H2S than the wild-type strain. Unlike cysteine, the addition of 10 mM pyruvate to the medium for a short time during the growth of the wild-type and sigL mutant strains reduced expression of the toxin genes, indicating that cysteine-dependent repression of toxin production is mainly due to the accumulation of cysteine by-products during growth. Finally, we showed that the effect of pyruvate on toxin gene expression is mediated at least in part by the two-component system CD2602-CD2601.
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André G, Haudecoeur E, Courtois E, Monot M, Dupuy B, Rodionov DA, Martin-Verstraete I. Cpe1786/IscR of Clostridium perfringens represses expression of genes involved in Fe-S cluster biogenesis. Res Microbiol 2016; 168:345-355. [PMID: 27020244 DOI: 10.1016/j.resmic.2016.03.002] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/30/2015] [Revised: 03/14/2016] [Accepted: 03/16/2016] [Indexed: 12/27/2022]
Abstract
Cpe1786 of Clostridium perfringens is an Rrf2-type regulator containing the three-cysteine residues coordinating a Fe-S in IscR, the repressor controlling Fe-S homeostasis in enterobacteria. The cpe1786 gene formed an operon with iscSU involved in Fe-S biogenesis and tmrU. This operon was transcribed from a σA-dependent promoter. We showed that in the heterologous host Bacillus subtilis, Cpe1786, renamed IscRCp, negatively controlled its own transcription. We constructed an iscR mutant in C. perfringens. We then compared the expression profile of strain 13 and of the iscR mutant. IscRCp controlled expression of genes involved in Fe-S biogenesis, in amino acid or sugar metabolisms, in fermentation pathways and in host compound utilization. We then demonstrated, using a ChIP-PCR experiment, that IscRCp interacted with its promoter region in vivo in C. perfringens and with the promoter of cpe2093 encoding an amino acid ABC transporter. We utilized a comparative genomic approach to infer a candidate IscR binding motif and reconstruct IscR regulons in clostridia. We showed that point mutations in the conserved motif of 29 bp identified upstream of iscR decreased the cysteine-dependent repression of iscR mediated by IscRCp.
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Affiliation(s)
- Gaelle André
- Institut Pasteur, Laboratoire de Pathogénèse des Bactéries anaérobies, 28 rue du Docteur Roux, 75015 Paris, France; Université Paris 7-Denis Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Elise Haudecoeur
- Institut Pasteur, Laboratoire de Pathogénèse des Bactéries anaérobies, 28 rue du Docteur Roux, 75015 Paris, France; Université Paris 7-Denis Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Emmanuelle Courtois
- Institut Pasteur, Laboratoire de Pathogénèse des Bactéries anaérobies, 28 rue du Docteur Roux, 75015 Paris, France; Université Paris 7-Denis Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Marc Monot
- Institut Pasteur, Laboratoire de Pathogénèse des Bactéries anaérobies, 28 rue du Docteur Roux, 75015 Paris, France; Université Paris 7-Denis Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Bruno Dupuy
- Institut Pasteur, Laboratoire de Pathogénèse des Bactéries anaérobies, 28 rue du Docteur Roux, 75015 Paris, France; Université Paris 7-Denis Diderot, Sorbonne Paris Cité, 75205 Paris, France
| | - Dmitry A Rodionov
- Institute for Information Transmission Problems, Russian Academy of Sciences, Moscow 127994, Russia
| | - Isabelle Martin-Verstraete
- Institut Pasteur, Laboratoire de Pathogénèse des Bactéries anaérobies, 28 rue du Docteur Roux, 75015 Paris, France; Université Paris 7-Denis Diderot, Sorbonne Paris Cité, 75205 Paris, France.
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29
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Choi AR, Kim MS, Kang SG, Lee HS. Dimethyl sulfoxide reduction by a hyperhermophilic archaeon Thermococcus onnurineus NA1 via a cysteine-cystine redox shuttle. J Microbiol 2016; 54:31-38. [DOI: 10.1007/s12275-016-5574-1] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/19/2015] [Accepted: 12/03/2015] [Indexed: 10/22/2022]
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30
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Ferrario C, Duranti S, Milani C, Mancabelli L, Lugli GA, Turroni F, Mangifesta M, Viappiani A, Ossiprandi MC, van Sinderen D, Ventura M. Exploring Amino Acid Auxotrophy in Bifidobacterium bifidum PRL2010. Front Microbiol 2015; 6:1331. [PMID: 26635786 PMCID: PMC4656816 DOI: 10.3389/fmicb.2015.01331] [Citation(s) in RCA: 32] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2015] [Accepted: 11/12/2015] [Indexed: 01/01/2023] Open
Abstract
The acquisition and assimilation strategies followed by members of the infant gut microbiota to retrieve nitrogen from the gut lumen are still largely unknown. In particular, no information on these metabolic processes is available regarding bifidobacteria, which are among the first microbial colonizers of the human intestine. Here, evaluation of amino acid auxotrophy and prototrophy of Bifidobacterium bifidum, with particular emphasis on B. bifidum strain PRL2010 (LMG S-28692), revealed a putative auxotrophy for cysteine. In addition, we hypothesized that cysteine plays a role in the oxidative stress response in B. bifidum. The use of glutathione as an alternative reduced sulfur compound did not alleviate cysteine auxotrophy of this strain, though it was shown to stimulate expression of the genes involved in cysteine biosynthesis, reminiscent of oxidative stress response. When PRL2010 was grown on a medium containing complex substrates, such as whey proteins or casein hydrolysate, we noticed a distinct growth-promoting effect of these compounds. Transcriptional analysis involving B. bifidum PRL2010 cultivated on whey proteins or casein hydrolysate revealed that the biosynthetic pathways for cysteine and methionine are modulated by the presence of casein hydrolysate. Such findings support the notion that certain complex substrates may act as potential prebiotics for bifidobacteria in their ecological niche.
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Affiliation(s)
- Chiara Ferrario
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Sabrina Duranti
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Christian Milani
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Leonardo Mancabelli
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Gabriele A Lugli
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | - Francesca Turroni
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
| | | | | | - Maria C Ossiprandi
- Department of Medical-Veterinary Science, University of Parma Parma, Italy
| | - Douwe van Sinderen
- APC Microbiome Institute and School of Microbiology, University College Cork, National University of Ireland Cork, Ireland
| | - Marco Ventura
- Laboratory of Probiogenomics, Department of Life Sciences, University of Parma Parma, Italy
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Hayashi S, Itoh K, Suyama K. Genes of Bacillus subtilis 168 that Support Growth of the Cyanobacterium, Synechococcus leopoliensis CCAP1405/1 on Agar Media. MICROBIAL ECOLOGY 2015; 70:849-852. [PMID: 25875741 DOI: 10.1007/s00248-015-0610-y] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/07/2014] [Accepted: 03/25/2015] [Indexed: 06/04/2023]
Abstract
Synechococcus leopoliensis CCAP1405/1 cannot grow on common solid media; however, the strain can grow when co-cultured with Bacillus subtilis 168. Gene-disruptant strains of B. subtilis 168 by pMUTINs at the following sites lost the ability to support the growth of S. leopoliensis CCAP1405/1 on agar media: yxeO and yufO (transporter), yxdK (histidine kinase), sdhC (succinate dehydrogenase), yvgQR (sulfite reductase), acoB (acetoin dehydrogenase), yusE (thioredoxin), yrdA (function unknown). Involvement of the assimilatory sulfate reduction pathway was the suggested reason for loss of the function.
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Affiliation(s)
- Shohei Hayashi
- Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, 690-8504, Japan
| | - Kazuhito Itoh
- Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, 690-8504, Japan.
| | - Kousuke Suyama
- Faculty of Life and Environmental Science, Shimane University, Matsue, Shimane, 690-8504, Japan
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The Use of a Mercury Biosensor to Evaluate the Bioavailability of Mercury-Thiol Complexes and Mechanisms of Mercury Uptake in Bacteria. PLoS One 2015; 10:e0138333. [PMID: 26371471 PMCID: PMC4570782 DOI: 10.1371/journal.pone.0138333] [Citation(s) in RCA: 23] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/27/2014] [Accepted: 08/25/2015] [Indexed: 11/19/2022] Open
Abstract
As mercury (Hg) biosensors are sensitive to only intracellular Hg, they are useful in the investigation of Hg uptake mechanisms and the effects of speciation on Hg bioavailability to microbes. In this study, bacterial biosensors were used to evaluate the roles that several transporters such as the glutathione, cystine/cysteine, and Mer transporters play in the uptake of Hg from Hg-thiol complexes by comparing uptake rates in strains with functioning transport systems to strains where these transporters had been knocked out by deletion of key genes. The Hg uptake into the biosensors was quantified based on the intracellular conversion of inorganic mercury (Hg(II)) to elemental mercury (Hg(0)) by the enzyme MerA. It was found that uptake of Hg from Hg-cysteine (Hg(CYS)2) and Hg-glutathione (Hg(GSH)2) complexes occurred at the same rate as that of inorganic complexes of Hg(II) into Escherichia coli strains with and without intact Mer transport systems. However, higher rates of Hg uptake were observed in the strain with a functioning Mer transport system. These results demonstrate that thiol-bound Hg is bioavailable to E. coli and that this bioavailability is higher in Hg-resistant bacteria with a complete Mer system than in non-resistant strains. No difference in the uptake rate of Hg from Hg(GSH)2 was observed in E. coli strains with or without functioning glutathione transport systems. There was also no difference in uptake rates between a wildtype Bacillus subtilis strain with a functioning cystine/cysteine transport system, and a mutant strain where this transport system had been knocked out. These results cast doubt on the viability of the hypothesis that the entire Hg-thiol complex is taken up into the cell by a thiol transporter. It is more likely that the Hg in the Hg-thiol complex is transferred to a transport protein on the cell membrane and is subsequently internalized.
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Physiological Roles and Adverse Effects of the Two Cystine Importers of Escherichia coli. J Bacteriol 2015; 197:3629-44. [PMID: 26350134 DOI: 10.1128/jb.00277-15] [Citation(s) in RCA: 57] [Impact Index Per Article: 6.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/09/2015] [Accepted: 09/02/2015] [Indexed: 12/20/2022] Open
Abstract
UNLABELLED When cystine is added to Escherichia coli, the bacterium becomes remarkably sensitive to hydrogen peroxide. This effect is due to enlarged intracellular pools of cysteine, which can drive Fenton chemistry. Genetic analysis linked the sensitivity to YdjN, a secondary transporter that along with the FliY-YecSC ABC system is responsible for cystine uptake. FliY-YecSC has a nanomolar Km and is essential for import of trace cystine, whereas YdjN has a micromolar Km and is the predominant importer when cystine is more abundant. Oddly, both systems are strongly induced by the CysB response to sulfur scarcity. The FliY-YecSC system can import a variety of biomolecules, including diaminopimelate; it is therefore vulnerable to competitive inhibition, presumably warranting YdjN induction under low-sulfur conditions. But the consequence is that if micromolar cystine then becomes available, the abundant YdjN massively overimports it, at >30 times the total sulfur demand of the cell. The imported cystine is rapidly reduced to cysteine in a glutathione-dependent process. This action avoids the hazard of disulfide stress, but it precludes feedback inhibition of YdjN by cystine. We conjecture that YdjN possesses no cysteine allosteric site because the isostructural amino acid serine might inappropriately bind in its place. Instead, the cell partially resolves the overaccumulation of cysteine by immediately excreting it, completing a futile import/reduction/export cycle that consumes a large amount of cellular energy. These unique, wasteful, and dangerous features of cystine metabolism are reproduced by other bacteria. We propose to rename ydjN as tcyP and fliY-yecSC as tcyJLN. IMPORTANCE In general, intracellular metabolite pools are kept at steady, nontoxic levels by a sophisticated combination of transcriptional and allosteric controls. Surprisingly, in E. coli allosteric control is utterly absent from the primary importer of cystine. This flaw allows massive overimport of cystine, which causes acute vulnerability to oxidative stress and is remedied only by wasteful cysteine efflux. The lack of import control may be rationalized by the unusual properties of cysteine itself. This phenomenon justifies the existence of countervailing cysteine export systems, whose purpose is otherwise hard to understand. It also highlights an unexpected link between sulfur metabolism and oxidative damage. Although this investigation focused upon E. coli, experiments confirmed that similar phenomena occur in other species.
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Ohtsu I, Kawano Y, Suzuki M, Morigasaki S, Saiki K, Yamazaki S, Nonaka G, Takagi H. Uptake of L-cystine via an ABC transporter contributes defense of oxidative stress in the L-cystine export-dependent manner in Escherichia coli. PLoS One 2015; 10:e0120619. [PMID: 25837721 PMCID: PMC4383340 DOI: 10.1371/journal.pone.0120619] [Citation(s) in RCA: 46] [Impact Index Per Article: 5.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/01/2014] [Accepted: 01/24/2015] [Indexed: 11/18/2022] Open
Abstract
Intracellular thiols like L-cystine and L-cystine play a critical role in the regulation of cellular processes. Here we show that Escherichia coli has two L-cystine transporters, the symporter YdjN and the ATP-binding cassette importer FliY-YecSC. These proteins import L-cystine, an oxidized product of L-cystine from the periplasm to the cytoplasm. The symporter YdjN, which is expected to be a new member of the L-cystine regulon, is a low affinity L-cystine transporter (Km = 1.1 μM) that is mainly involved in L-cystine uptake from outside as a nutrient. E. coli has only two L-cystine importers because ΔydjNΔyecS mutant cells are not capable of growing in the minimal medium containing L-cystine as a sole sulfur source. Another protein YecSC is the FliY-dependent L-cystine transporter that functions cooperatively with the L-cystine transporter YdeD, which exports L-cystine as reducing equivalents from the cytoplasm to the periplasm, to prevent E. coli cells from oxidative stress. The exported L-cystine can reduce the periplasmic hydrogen peroxide to water, and then generated L-cystine is imported back into the cytoplasm via the ATP-binding cassette transporter YecSC with a high affinity to L-cystine (Km = 110 nM) in a manner dependent on FliY, the periplasmic L-cystine-binding protein. The double disruption of ydeD and fliY increased cellular levels of lipid peroxides. From these findings, we propose that the hydrogen peroxide-inducible L-cystine/L-cystine shuttle system plays a role of detoxification of hydrogen peroxide before lipid peroxidation occurs, and then might specific prevent damage to membrane lipids.
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Affiliation(s)
- Iwao Ohtsu
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara, Japan
- * E-mail:
| | - Yusuke Kawano
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara, Japan
| | - Marina Suzuki
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara, Japan
| | - Susumu Morigasaki
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara, Japan
| | - Kyohei Saiki
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara, Japan
| | - Shunsuke Yamazaki
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Company, Kawasaki, Kanagawa, Japan
| | - Gen Nonaka
- Research Institute for Bioscience Products and Fine Chemicals, Ajinomoto Company, Kawasaki, Kanagawa, Japan
| | - Hiroshi Takagi
- Graduate School of Biological Sciences, Nara Institute of Science and Technology, Ikoma, Nara, Japan
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Deutch C, Spahija I, Wagner C. Susceptibility of Escherichia coli
to the toxic L-proline analogue L-selenaproline is dependent on two L-cystine transport systems. J Appl Microbiol 2014; 117:1487-99. [PMID: 25139244 DOI: 10.1111/jam.12623] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/29/2014] [Revised: 08/11/2014] [Accepted: 08/14/2014] [Indexed: 11/30/2022]
Affiliation(s)
- C.E. Deutch
- School of Mathematical and Natural Sciences; Arizona State University at the West Campus; Phoenix AZ USA
| | - I. Spahija
- School of Mathematical and Natural Sciences; Arizona State University at the West Campus; Phoenix AZ USA
| | - C.E. Wagner
- School of Mathematical and Natural Sciences; Arizona State University at the West Campus; Phoenix AZ USA
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The cysteine desulfhydrase CdsH is conditionally required for sulfur mobilization to the thiamine thiazole in Salmonella enterica. J Bacteriol 2014; 196:3964-70. [PMID: 25182497 DOI: 10.1128/jb.02159-14] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/11/2023] Open
Abstract
Thiamine pyrophosphate is a required coenzyme that contains a mechanistically important sulfur atom. In Salmonella enterica, sulfur is trafficked to both thiamine biosynthesis and 4-thiouridine biosynthesis by the enzyme ThiI using persulfide (R-S-S-H) chemistry. It was previously reported that a thiI mutant strain could grow independent of exogenous thiamine in the presence of cysteine, suggesting there was a second mechanism for sulfur mobilization. Data reported here show that oxidation products of cysteine rescue the growth of a thiI mutant strain by a mechanism that requires the transporter YdjN and the cysteine desulfhydrase CdsH. The data are consistent with a model in which sulfide produced by CdsH reacts with cystine (Cys-S-S-Cys), S-sulfocysteine (Cys-S-SO3 (-)), or another disulfide to form a small-molecule persulfide (R-S-S-H). We suggest that this persulfide replaced ThiI by donating sulfur to the thiamine sulfur carrier protein ThiS. This model describes a potential mechanism used for sulfur trafficking in organisms that lack ThiI but are capable of thiamine biosynthesis.
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Halbedel S, Reiss S, Hahn B, Albrecht D, Mannala GK, Chakraborty T, Hain T, Engelmann S, Flieger A. A systematic proteomic analysis of Listeria monocytogenes house-keeping protein secretion systems. Mol Cell Proteomics 2014; 13:3063-81. [PMID: 25056936 DOI: 10.1074/mcp.m114.041327] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Listeria monocytogenes is a firmicute bacterium causing serious infections in humans upon consumption of contaminated food. Most of its virulence factors are secretory proteins either released to the medium or attached to the bacterial surface. L. monocytogenes encodes at least six different protein secretion pathways. Although great efforts have been made in the past to predict secretory proteins and their secretion routes using bioinformatics, experimental evidence is lacking for most secretion systems. Therefore, we constructed mutants in the main housekeeping protein secretion systems, which are the Sec-dependent transport, the YidC membrane insertases SpoIIIJ and YqjG, as well as the twin-arginine pathway, and analyzed their secretion and virulence defects. Our results demonstrate that Sec-dependent secretion and membrane insertion of proteins via YidC proteins are essential for viability of L. monocytogenes. Depletion of SecA or YidC activity severely affected protein secretion, whereas loss of the Tat-pathway was without any effect on secretion, viability, and virulence. Two-dimensional gel electrophoresis combined with protein identification by mass spectrometry revealed that secretion of many virulence factors and of enzymes synthesizing and degrading the cell wall depends on the SecA route. This finding was confirmed by SecA inhibition experiments using sodium azide. Analysis of secretion of substrates typically dependent on the accessory SecA2 ATPase in wild type and azide resistant mutants of L. monocytogenes revealed for the first time that SecA2-dependent protein secretion also requires the ATPase activity of the house-keeping SecA protein.
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Affiliation(s)
- Sven Halbedel
- From the ‡Robert Koch Institute, FG11 - Division of Enteropathogenic Bacteria and Legionella, Burgstrasse 37, 38855 Wernigerode, Germany;
| | - Swantje Reiss
- §Institute of Microbiology, University of Greifswald, F.-L.-Jahn-Strasse 15, 17487 Greifswald, Germany
| | - Birgit Hahn
- From the ‡Robert Koch Institute, FG11 - Division of Enteropathogenic Bacteria and Legionella, Burgstrasse 37, 38855 Wernigerode, Germany
| | - Dirk Albrecht
- §Institute of Microbiology, University of Greifswald, F.-L.-Jahn-Strasse 15, 17487 Greifswald, Germany
| | - Gopala Krishna Mannala
- ¶Institute of Medical Microbiology, University of Gießen, Schubertstrasse 81, 35392 Gießen, Germany
| | - Trinad Chakraborty
- ¶Institute of Medical Microbiology, University of Gießen, Schubertstrasse 81, 35392 Gießen, Germany
| | - Torsten Hain
- ¶Institute of Medical Microbiology, University of Gießen, Schubertstrasse 81, 35392 Gießen, Germany
| | - Susanne Engelmann
- §Institute of Microbiology, University of Greifswald, F.-L.-Jahn-Strasse 15, 17487 Greifswald, Germany; ‖Institute of Microbiology, Technical University of Braunschweig, Spielmannstrasse 7, 38106 Braunschweig, Germany; **Helmholtz Centre for Infection Research, Microbial Proteomics, Inhoffenstrasse 7, 38124 Braunschweig, Germany
| | - Antje Flieger
- From the ‡Robert Koch Institute, FG11 - Division of Enteropathogenic Bacteria and Legionella, Burgstrasse 37, 38855 Wernigerode, Germany;
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38
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The transcriptional response of Lactobacillus sanfranciscensis DSM 20451T and its tcyB mutant lacking a functional cystine transporter to diamide stress. Appl Environ Microbiol 2014; 80:4114-25. [PMID: 24795368 DOI: 10.1128/aem.00367-14] [Citation(s) in RCA: 12] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
As a result of its strong adaptation to wheat and rye sourdoughs, Lactobacillus sanfranciscensis has the smallest genome within the genus Lactobacillus. The concomitant absence of some important antioxidative enzymes and the inability to synthesize glutathione suggest a role of cystine transport in maintenance of an intracellular thiol balance. Diamide [synonym 1,1'-azobis(N,N-dimethylformamide)] disturbs intracellular and membrane thiol levels in oxidizing protein thiols depending on its initial concentration. In this study, RNA sequencing was used to reveal the transcriptional response of L. sanfranciscensis DSM 20451(T) (wild type [WT]) and its ΔtcyB mutant with a nonfunctional cystine transporter after thiol stress caused by diamide. Along with the different expression of genes involved in amino acid starvation, pyrimidine synthesis, and energy production, our results show that thiol stress in the wild type can be compensated through activation of diverse chaperones and proteases whereas the ΔtcyB mutant shifts its metabolism in the direction of survival. Only a small set of genes are significantly differentially expressed between the wild type and the mutant. In the WT, mainly genes which are associated with a heat shock response are upregulated whereas glutamine import and synthesis genes are downregulated. In the ΔtcyB mutant, the whole opp operon was more highly expressed, as well as a protein which probably includes enzymes for methionine transport. The two proteins encoded by spxA and nrdH, which are involved in direct or indirect oxidative stress responses, are also upregulated in the mutant. This work emphasizes that even in the absence of definitive antioxidative enzymes, bacteria with a small genome and a high frequency of gene inactivation and elimination use small molecules such as the cysteine/cystine couple to overcome potential cell damage resulting from oxidative stress.
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39
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Paritala H, Carroll KS. New targets and inhibitors of mycobacterial sulfur metabolism. Infect Disord Drug Targets 2013; 13:85-115. [PMID: 23808874 PMCID: PMC4332622 DOI: 10.2174/18715265113139990022] [Citation(s) in RCA: 31] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/16/2013] [Accepted: 05/08/2013] [Indexed: 11/22/2022]
Abstract
The identification of new antibacterial targets is urgently needed to address multidrug resistant and latent tuberculosis infection. Sulfur metabolic pathways are essential for survival and the expression of virulence in many pathogenic bacteria, including Mycobacterium tuberculosis. In addition, microbial sulfur metabolic pathways are largely absent in humans and therefore, represent unique targets for therapeutic intervention. In this review, we summarize our current understanding of the enzymes associated with the production of sulfated and reduced sulfur-containing metabolites in Mycobacteria. Small molecule inhibitors of these catalysts represent valuable chemical tools that can be used to investigate the role of sulfur metabolism throughout the Mycobacterial lifecycle and may also represent new leads for drug development. In this light, we also summarize recent progress made in the development of inhibitors of sulfur metabolism enzymes.
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Affiliation(s)
| | - Kate S. Carroll
- Department of Chemistry, The Scripps Research Institute, Jupiter, Florida, 33458, USA
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40
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Huillet E, Tempelaars MH, André-Leroux G, Wanapaisan P, Bridoux L, Makhzami S, Panbangred W, Martin-Verstraete I, Abee T, Lereclus D. PlcRa, a new quorum-sensing regulator from Bacillus cereus, plays a role in oxidative stress responses and cysteine metabolism in stationary phase. PLoS One 2012; 7:e51047. [PMID: 23239999 PMCID: PMC3519770 DOI: 10.1371/journal.pone.0051047] [Citation(s) in RCA: 21] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2012] [Accepted: 10/29/2012] [Indexed: 12/31/2022] Open
Abstract
We characterized a new quorum-sensing regulator, PlcRa, which is present in various members of the B. cereus group and identified a signaling heptapeptide for PlcRa activity: PapRa7. We demonstrated that PlcRa is a 3D structural paralog of PlcR using sequence analysis and homology modeling. A comparison of the transcriptomes at the onset of stationary phase of a ΔplcRa mutant and the wild-type B. cereus ATCC 14579 strain showed that 68 genes were upregulated and 49 genes were downregulated in the ΔplcRa mutant strain (>3-fold change). Genes involved in the cysteine metabolism (putative CymR regulon) were downregulated in the ΔplcRa mutant strain. We focused on the gene with the largest difference in expression level between the two conditions, which encoded -AbrB2- a new regulator of the AbrB family. We demonstrated that purified PlcRa bound specifically to the abrB2 promoter in the presence of synthetic PapRa7, in an electrophoretic mobility shift assay. We further showed that the AbrB2 regulator controlled the expression of the yrrT operon involved in methionine to cysteine conversion. We found that the ΔplcRa mutant strain was more sensitive to hydrogen peroxide- and disulfide-induced stresses than the wild type. When cystine was added to the culture of the ΔplcRa mutant, challenged with hydrogen peroxide, growth inhibition was abolished. In conclusion, we identified a new RNPP transcriptional regulator in B. cereus that activated the oxidative stress response and cysteine metabolism in transition state cells.
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Affiliation(s)
- Eugénie Huillet
- INRA, UMR1319 Micalis, Génétique microbienne et Environnement, Guyancourt, France
- * E-mail: (EH); (DL)
| | - Marcel H. Tempelaars
- Wageningen University, Laboratory of Food Microbiology, Wageningen, The Netherlands
| | | | - Pagakrong Wanapaisan
- INRA, UMR1319 Micalis, Génétique microbienne et Environnement, Guyancourt, France
- Mahidol University, Department of Biotechnology, Faculty of Science, Bangkok, Thailand
| | - Ludovic Bridoux
- INRA, UMR1319 Micalis, Génétique microbienne et Environnement, Guyancourt, France
| | | | - Watanalai Panbangred
- Mahidol University, Department of Biotechnology, Faculty of Science, Bangkok, Thailand
| | - Isabelle Martin-Verstraete
- Institut Pasteur, Laboratoire de Pathogénèse des Bactéries Anaérobies, Paris, France
- Univ. Paris Diderot, Sorbonne Paris Cité, Cellule Pasteur, Paris, France
| | - Tjakko Abee
- Wageningen University, Laboratory of Food Microbiology, Wageningen, The Netherlands
| | - Didier Lereclus
- INRA, UMR1319 Micalis, Génétique microbienne et Environnement, Guyancourt, France
- * E-mail: (EH); (DL)
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Glekas GD, Mulhern BJ, Kroc A, Duelfer KA, Lei V, Rao CV, Ordal GW. The Bacillus subtilis chemoreceptor McpC senses multiple ligands using two discrete mechanisms. J Biol Chem 2012; 287:39412-8. [PMID: 23038252 DOI: 10.1074/jbc.m112.413518] [Citation(s) in RCA: 62] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Bacillus subtilis can perform chemotaxis toward all 20 L-amino acids normally found in proteins. Loss of a single chemoreceptor, McpC, was previously found to reduce chemotaxis to 19 of these amino acids. In this study, we investigated the amino acid-sensing mechanism of McpC. We show that McpC alone can support chemotaxis to 17 of these amino acids to varying degrees. Eleven amino acids were found to directly bind the amino-terminal sensing domain of McpC in vitro. Sequence analysis indicates that the McpC sensing domain exhibits a dual Per-Arnt-Sim (PAS) domain structure. Using this structure as a guide, we were able to isolate mutants that suggest that four amino acids (arginine, glutamine, lysine, and methionine) are sensed by an indirect mechanism. We identified four candidate binding lipoproteins associated with amino acid transporters that may function in indirect sensing: ArtP, GlnH, MetQ, and YckB. ArtP was found to bind arginine and lysine; GlnH, glutamine; MetQ, methionine; and YckB, tryptophan. In addition, we found that ArtP, MetQ, and YckB bind the sensing domain of McpC, suggesting that the three participate in the indirect sensing of arginine, lysine, methionine, and possibly tryptophan as well. Taken together, these results further our understanding of amino acid chemotaxis in B. subtilis and gain insight into how a single chemoreceptor is able to sense many amino acids.
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Affiliation(s)
- George D Glekas
- Department of Biochemistry, University of Illinois, Urbana, Illinois 61801, USA
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Rochat T, Nicolas P, Delumeau O, Rabatinová A, Korelusová J, Leduc A, Bessières P, Dervyn E, Krásny L, Noirot P. Genome-wide identification of genes directly regulated by the pleiotropic transcription factor Spx in Bacillus subtilis. Nucleic Acids Res 2012; 40:9571-83. [PMID: 22904090 PMCID: PMC3479203 DOI: 10.1093/nar/gks755] [Citation(s) in RCA: 73] [Impact Index Per Article: 6.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/14/2022] Open
Abstract
The transcriptional regulator Spx plays a key role in maintaining the redox homeostasis of Bacillus subtilis cells exposed to disulfide stress. Defects in Spx were previously shown to lead to differential expression of numerous genes but direct and indirect regulatory effects could not be distinguished. Here we identified 283 discrete chromosomal sites potentially bound by the Spx–RNA polymerase (Spx–RNAP) complex using chromatin immunoprecipitation of Spx. Three quarters of these sites were located near Sigma(A)-dependent promoters, and upon diamide treatment, the fraction of the Spx–RNAP complex increased in parallel with the number and occupancy of DNA sites. Correlation of Spx–RNAP-binding sites with gene differential expression in wild-type and Δspx strains exposed or not to diamide revealed that 144 transcription units comprising 275 genes were potentially under direct Spx regulation. Spx-controlled promoters exhibited an extended −35 box in which nucleotide composition at the −43/−44 positions strongly correlated with observed activation. In vitro transcription confirmed activation by oxidized Spx of seven newly identified promoters, of which one was also activated by reduced Spx. Our study globally characterized the Spx regulatory network, revealing its role in the basal expression of some genes and its complex interplay with other stress responses.
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43
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Groot Kormelink T, Koenders E, Hagemeijer Y, Overmars L, Siezen RJ, de Vos WM, Francke C. Comparative genome analysis of central nitrogen metabolism and its control by GlnR in the class Bacilli. BMC Genomics 2012; 13:191. [PMID: 22607086 PMCID: PMC3412718 DOI: 10.1186/1471-2164-13-191] [Citation(s) in RCA: 30] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/23/2011] [Accepted: 03/20/2012] [Indexed: 11/10/2022] Open
Abstract
BACKGROUND The assimilation of nitrogen in bacteria is achieved through only a few metabolic conversions between alpha-ketoglutarate, glutamate and glutamine. The enzymes that catalyze these conversions are glutamine synthetase, glutaminase, glutamate dehydrogenase and glutamine alpha-ketoglutarate aminotransferase. In low-GC Gram-positive bacteria the transcriptional control over the levels of the related enzymes is mediated by four regulators: GlnR, TnrA, GltC and CodY. We have analyzed the genomes of all species belonging to the taxonomic families Bacillaceae, Listeriaceae, Staphylococcaceae, Lactobacillaceae, Leuconostocaceae and Streptococcaceae to determine the diversity in central nitrogen metabolism and reconstructed the regulation by GlnR. RESULTS Although we observed a substantial difference in the extent of central nitrogen metabolism in the various species, the basic GlnR regulon was remarkably constant and appeared not affected by the presence or absence of the other three main regulators. We found a conserved regulatory association of GlnR with glutamine synthetase (glnRA operon), and the transport of ammonium (amtB-glnK) and glutamine/glutamate (i.e. via glnQHMP, glnPHQ, gltT, alsT). In addition less-conserved associations were found with, for instance, glutamate dehydrogenase in Streptococcaceae, purine catabolism and the reduction of nitrite in Bacillaceae, and aspartate/asparagine deamination in Lactobacillaceae. CONCLUSIONS Our analyses imply GlnR-mediated regulation in constraining the import of ammonia/amino-containing compounds and the production of intracellular ammonia under conditions of high nitrogen availability. Such a role fits with the intrinsic need for tight control of ammonia levels to limit futile cycling.
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Affiliation(s)
- Tom Groot Kormelink
- Kluyver Centre for Genomics of Industrial Fermentation, Delft, The Netherlands
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44
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Computational analysis of cysteine and methionine metabolism and its regulation in dairy starter and related bacteria. J Bacteriol 2012; 194:3522-33. [PMID: 22522891 DOI: 10.1128/jb.06816-11] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/20/2022] Open
Abstract
Sulfuric volatile compounds derived from cysteine and methionine provide many dairy products with a characteristic odor and taste. To better understand and control the environmental dependencies of sulfuric volatile compound formation by the dairy starter bacteria, we have used the available genome sequence and experimental information to systematically evaluate the presence of the key enzymes and to reconstruct the general modes of transcription regulation for the corresponding genes. The genomic organization of the key genes is suggestive of a subdivision of the reaction network into five modules, where we observed distinct differences in the modular composition between the families Lactobacillaceae, Enterococcaceae, and Leuconostocaceae, on the one hand, and the family Streptococcaceae, on the other. These differences are mirrored by the way in which transcription regulation of the genes is structured in these families. In the Lactobacillaceae, Enterococcaceae, and Leuconostocaceae, the main shared mode of transcription regulation is methionine (Met) T-box-mediated regulation. In addition, the gene metK, encoding S-adenosylmethionine (SAM) synthetase, is controlled via the S(MK) box (SAM). The S(MK) box is also found upstream of metK in species of the family Streptococcaceae. However, the transcription control of the other modules is mediated via three different LysR-family regulators, MetR/MtaR (methionine), CmbR (O-acetyl[homo]serine), and HomR (O-acetylhomoserine). Redefinition of the associated DNA-binding motifs helped to identify/disentangle the related regulons, which appeared to perfectly match the proposed subdivision of the reaction network.
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45
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Kim J, Senadheera DB, Lévesque CM, Cvitkovitch DG. TcyR regulates L-cystine uptake via the TcyABC transporter in Streptococcus mutans. FEMS Microbiol Lett 2012; 328:114-21. [PMID: 22212096 DOI: 10.1111/j.1574-6968.2011.02492.x] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2011] [Revised: 12/13/2011] [Accepted: 12/13/2011] [Indexed: 11/28/2022] Open
Abstract
Streptococcus mutans, a primary dental pathogen, has a remarkable capacity to scavenge nutrients from the oral biofilm for its survival. Cystine is an amino acid dimer formed by the oxidation of two cysteine residues that is required for optimal growth of S. mutans, which modulates l-cystine uptake via two recently identified transporters designated TcyABC and TcyDEFGH, which have not been fully characterized. Using a nonpolar tcyABC-deficient mutant (SmTcyABC), here, we report that l-cystine uptake is drastically diminished in the mutant, whereas its ability to grow is severely impaired under l-cystine starvation conditions, relative to wild type. A substrate competition assay showed that l-cystine uptake by the TcyABC transporter was strongly inhibited by dl-cystathionine and l-djenkolic acid and moderately inhibited by S-methyl-l-cysteine and l-cysteine. Using gene expression analysis, we observed that the tcyABC operon was upregulated under cystine starvation. TcyABC has been shown to be positively regulated by the LysR-type transcriptional regulator CysR. We identified another LysR-type transcriptional regulator that negatively regulates TcyABC with homology to the Bacillus subtilis YtlI regulator, which we termed TcyR. Our study enhances the understanding of l-cystine uptake in S. mutans, which allows survival and persistence of this pathogen in the oral biofilm.
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Affiliation(s)
- Jennifer Kim
- Dental Research Institute, University of Toronto, Toronto, ON, Canada
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46
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Bulut H, Moniot S, Licht A, Scheffel F, Gathmann S, Saenger W, Schneider E. Crystal Structures of Two Solute Receptors for l-Cystine and l-Cysteine, Respectively, of the Human Pathogen Neisseria gonorrhoeae. J Mol Biol 2012; 415:560-72. [DOI: 10.1016/j.jmb.2011.11.030] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2011] [Revised: 11/09/2011] [Accepted: 11/16/2011] [Indexed: 11/26/2022]
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Eggers CH, Caimano MJ, Malizia RA, Kariu T, Cusack B, Desrosiers DC, Hazlett KRO, Claiborne A, Pal U, Radolf JD. The coenzyme A disulphide reductase of Borrelia burgdorferi is important for rapid growth throughout the enzootic cycle and essential for infection of the mammalian host. Mol Microbiol 2011; 82:679-97. [PMID: 21923763 DOI: 10.1111/j.1365-2958.2011.07845.x] [Citation(s) in RCA: 38] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
In a microarray analysis of the RpoS regulon in mammalian host-adapted Borrelia burgdorferi, bb0728 (cdr) was found to be dually transcribed by the sigma factors σ(70) and RpoS. The cdr gene encodes a coenzyme A disulphide reductase (CoADR) that reduces CoA-disulphides to CoA in an NADH-dependent manner. Based on the abundance of CoA in B. burgdorferi and the biochemistry of the enzyme, CoADR has been proposed to play a role in the spirochaete's response to reactive oxygen species. To better understand the physiologic function(s) of BbCoADR, we generated a B. burgdorferi mutant in which the cdr gene was disrupted. RT-PCR and 5'-RACE analysis revealed that cdr and bb0729 are co-transcribed from a single transcriptional start site upstream of the bb0729 coding sequence; a shuttle vector containing the bb0729-cdr operon and upstream promoter element was used to complement the cdr mutant. Although the mutant was no more sensitive to hydrogen peroxide than its parent, it did exhibit increased sensitivity to high concentrations of t-butyl-hydroperoxide, an oxidizing compound that damages spirochetal membranes. Characterization of the mutant during standard (15% oxygen, 6% CO(2)) and anaerobic (< 1% O(2) , 9-13% CO(2)) cultivation at 37°C revealed a growth defect under both conditions that was particularly striking during anaerobiosis. The mutant was avirulent by needle inoculation and showed decreased survival in feeding nymphs, but displayed no survival defect in unfed flat nymphs. Based on these results, we propose that BbCoADR is necessary to maintain optimal redox ratios for CoA/CoA-disulphide and NAD(+) /NADH during periods of rapid replication throughout the enzootic cycle, to support thiol-disulphide homeostasis, and to indirectly protect the spirochaete against peroxide-mediated membrane damage; one or more of these functions are essential for infection of the mammalian host by B. burgdorferi.
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Affiliation(s)
- Christian H Eggers
- Department of Biomedical Sciences, Quinnipiac University, Hamden, CT 06518, USA.
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Goelzer A, Fromion V. Bacterial growth rate reflects a bottleneck in resource allocation. Biochim Biophys Acta Gen Subj 2011; 1810:978-88. [PMID: 21689729 DOI: 10.1016/j.bbagen.2011.05.014] [Citation(s) in RCA: 77] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/01/2010] [Revised: 05/17/2011] [Accepted: 05/20/2011] [Indexed: 02/06/2023]
Abstract
BACKGROUND Growth rate management in fast-growing bacteria is currently an active research area. In spite of the huge progress made in our understanding of the molecular mechanisms controlling the growth rate, fundamental questions concerning its intrinsic limitations are still relevant today. In parallel, systems biology claims that mathematical models could shed light on these questions. METHODS This review explores some possible reasons for the limitation of the growth rate in fast-growing bacteria, using a systems biology approach based on constraint-based modeling methods. RESULTS Recent experimental results and a new constraint-based modelling method named Resource Balance Analysis (RBA) reveal the existence of constraints on resource allocation between biological processes in bacterial cells. In this context, the distribution of a finite amount of resources between the metabolic network and the ribosomes limits the growth rate, which implies the existence of a bottleneck between these two processes. Any mechanism for saving resources increases the growth rate. GENERAL SIGNIFICANCE Consequently, the emergence of genetic regulation of metabolic pathways, e.g. catabolite repression, could then arise as a means to minimise the protein cost, i.e. maximising growth performance while minimising the resource allocation. This article is part of a Special Issue entitled Systems Biology of Microorganisms.
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Affiliation(s)
- A Goelzer
- Institut National de la Recherche en Agronomie, Unité de Mathématique, Informatique et Génome, Jouy-en-Josas, France.
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Yadav AK, Bachhawat AK. CgCYN1, a plasma membrane cystine-specific transporter of Candida glabrata with orthologues prevalent among pathogenic yeast and fungi. J Biol Chem 2011; 286:19714-23. [PMID: 21507960 PMCID: PMC3103350 DOI: 10.1074/jbc.m111.240648] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2011] [Revised: 04/19/2011] [Indexed: 11/06/2022] Open
Abstract
We describe a novel plasma membrane cystine transporter, CgCYN1, from Candida glabrata, the first such transporter to be described from yeast and fungi. C. glabrata met15Δ strains, organic sulfur auxotrophs, were observed to utilize cystine as a sulfur source, and this phenotype was exploited in the discovery of CgCYN1. Heterologous expression of CgCYN1 in Saccharomyces cerevisiae met15Δ strains conferred the ability of S. cerevisiae strains to grow on cystine. Deletion of the CgCYN1 ORF (CAGL0M00154g) in C. glabrata met15Δ strains caused abrogation of growth on cystine with growth being restored when CgCYN1 was reintroduced. The CgCYN1 protein belongs to the amino acid permease family of transporters, with no similarity to known plasma membrane cystine transporters of bacteria and humans, or lysosomal cystine transporters of humans/yeast. Kinetic studies revealed a K(m) of 18 ± 5 μM for cystine. Cystine uptake was inhibited by cystine, but not by other amino acids, including cysteine. The structurally similar cystathionine, lanthionine, and selenocystine alone inhibited transport, confirming that the transporter was specific for cystine. CgCYN1 localized to the plasma membrane and transport was energy-dependent. Functional orthologues could be demonstrated from other pathogenic yeast like Candida albicans and Histoplasma capsulatum, but were absent in Schizosaccharomyces pombe and S. cerevisiae.
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Affiliation(s)
- Amit Kumar Yadav
- From the Institute of Microbial Technology (Council of Scientific and Industrial Research), Sector 39-A, Chandigarh 160 036, India and
| | - Anand Kumar Bachhawat
- From the Institute of Microbial Technology (Council of Scientific and Industrial Research), Sector 39-A, Chandigarh 160 036, India and
- the Indian Institute of Science Education and Research (IISER Mohali), Mahatma Gandhi State Institute of Public Administration Punjab Complex, Sector 26, Chandigarh 160 019, India
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Botella E, Hübner S, Hokamp K, Hansen A, Bisicchia P, Noone D, Powell L, Salzberg LI, Devine KM. Cell envelope gene expression in phosphate-limited Bacillus subtilis cells. MICROBIOLOGY-SGM 2011; 157:2470-2484. [PMID: 21636651 DOI: 10.1099/mic.0.049205-0] [Citation(s) in RCA: 33] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
The high phosphate content of Bacillus subtilis cell walls dictates that cell wall metabolism is an important feature of the PhoPR-mediated phosphate limitation response. Here we report the expression profiles of cell-envelope-associated and PhoPR regulon genes, determined by live cell array and transcriptome analysis, in exponentially growing and phosphate-limited B. subtilis cells. Control by the WalRK two-component system confers a unique expression profile and high level of promoter activity on the genes of its regulon with yocH and cwlO expression differing both qualitatively and quantitatively from all other autolysin-encoding genes examined. The activity of the PhoPR two-component system is restricted to the phosphate-limited state, being rapidly induced in response to the cognate stimulus, and can be sustained for an extended phosphate limitation period. Constituent promoters of the PhoPR regulon show heterogeneous induction profiles and very high promoter activities. Phosphate-limited cells also show elevated expression of the actin-like protein MreBH and reduced expression of the WapA cell wall protein and WprA cell wall protease indicating that cell wall metabolism in this state is distinct from that of exponentially growing and stationary-phase cells. The PhoPR response is very rapidly deactivated upon removal of the phosphate limitation stimulus with concomitant increased expression of cell wall metabolic genes. Moreover expression of genes encoding enzymes involved in sulphur metabolism is significantly altered in the phosphate-limited state with distinct perturbations being observed in wild-type 168 and AH024 (ΔphoPR) cells.
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Affiliation(s)
- Eric Botella
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Sebastian Hübner
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Karsten Hokamp
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Annette Hansen
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Paola Bisicchia
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - David Noone
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Leagh Powell
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Letal I Salzberg
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
| | - Kevin M Devine
- Smurfit Institute of Genetics, Trinity College Dublin, Dublin 2, Ireland
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