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Kambhampati S, Hubbard AH, Koley S, Gomez JD, Marsolais F, Evans BS, Young JD, Allen DK. SIMPEL: using stable isotopes to elucidate dynamics of context specific metabolism. Commun Biol 2024; 7:172. [PMID: 38347116 PMCID: PMC10861564 DOI: 10.1038/s42003-024-05844-z] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/03/2022] [Accepted: 01/23/2024] [Indexed: 02/15/2024] Open
Abstract
The capacity to leverage high resolution mass spectrometry (HRMS) with transient isotope labeling experiments is an untapped opportunity to derive insights on context-specific metabolism, that is difficult to assess quantitatively. Tools are needed to comprehensively mine isotopologue information in an automated, high-throughput way without errors. We describe a tool, Stable Isotope-assisted Metabolomics for Pathway Elucidation (SIMPEL), to simplify analysis and interpretation of isotope-enriched HRMS datasets. The efficacy of SIMPEL is demonstrated through examples of central carbon and lipid metabolism. In the first description, a dual-isotope labeling experiment is paired with SIMPEL and isotopically nonstationary metabolic flux analysis (INST-MFA) to resolve fluxes in central metabolism that would be otherwise challenging to quantify. In the second example, SIMPEL was paired with HRMS-based lipidomics data to describe lipid metabolism based on a single labeling experiment. Available as an R package, SIMPEL extends metabolomics analyses to include isotopologue signatures necessary to quantify metabolic flux.
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Affiliation(s)
- Shrikaar Kambhampati
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA.
- Jack H. Skirball Center for Chemical Biology and Proteomics, The Salk Institute for Biological Studies, La Jolla, CA, 92037, USA.
| | - Allen H Hubbard
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
| | - Somnath Koley
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
| | - Javier D Gomez
- Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37235, USA
| | - Frédéric Marsolais
- London Research and Development Center, London, ON, N5V 4T3, Canada
- Department of Biology, University of Western Ontario, London, ON, N6A 5B7, Canada
| | - Bradley S Evans
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA
| | - Jamey D Young
- Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37235, USA
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, 37235, USA
| | - Doug K Allen
- Donald Danforth Plant Science Center, St. Louis, MO, 63132, USA.
- Agricultural Research Service, US Department of Agriculture, St. Louis, MO, 63132, USA.
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2
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Gomez JD, Wall ML, Rahim M, Kambhampati S, Evans BS, Allen DK, Antoniewicz MR, Young JD. Program for Integration and Rapid Analysis of Mass Isotopomer Distributions (PIRAMID). Bioinformatics 2023; 39:btad661. [PMID: 37889279 PMCID: PMC10636274 DOI: 10.1093/bioinformatics/btad661] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/20/2022] [Revised: 04/26/2023] [Accepted: 10/25/2023] [Indexed: 10/28/2023] Open
Abstract
SUMMARY The analysis of stable isotope labeling experiments requires accurate, efficient, and reproducible quantification of mass isotopomer distributions (MIDs), which is not a core feature of general-purpose metabolomics software tools that are optimized to quantify metabolite abundance. Here, we present PIRAMID (Program for Integration and Rapid Analysis of Mass Isotopomer Distributions), a MATLAB-based tool that addresses this need by offering a user-friendly, graphical user interface-driven program to automate the extraction of isotopic information from mass spectrometry (MS) datasets. This tool can simultaneously extract ion chromatograms for various metabolites from multiple data files in common vendor-agnostic file formats, locate chromatographic peaks based on a targeted list of characteristic ions and retention times, and integrate MIDs for each target ion. These MIDs can be corrected for natural isotopic background based on the user-defined molecular formula of each ion. PIRAMID offers support for datasets acquired from low- or high-resolution MS, and single (MS) or tandem (MS/MS) instruments. It also enables the analysis of single or dual labeling experiments using a variety of isotopes (i.e. 2H, 13C, 15N, 18O, 34S). DATA AVAILABILITY AND IMPLEMENTATION MATLAB p-code files are freely available for non-commercial use and can be downloaded from https://mfa.vueinnovations.com/. Commercial licenses are also available. All the data presented in this publication are available under the "Help_menu" folder of the PIRAMID software.
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Affiliation(s)
- Javier D Gomez
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37240, United States
| | - Martha L Wall
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37240, United States
| | - Mohsin Rahim
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37240, United States
| | | | - Bradley S Evans
- Donald Danforth Plant Science Center, Olviette, MO, 63132, United States
| | - Doug K Allen
- Donald Danforth Plant Science Center, Olviette, MO, 63132, United States
- United States Department of Agriculture, Agricultural Research Service, Washington, DC, 20250, United States
| | - Maciek R Antoniewicz
- Department of Chemical Engineering, Massachusetts Institute of Technology, Cambridge, MA, 02139, United States
| | - Jamey D Young
- Department of Chemical and Biomolecular Engineering, Vanderbilt University, Nashville, TN, 37240, United States
- Department of Molecular Physiology and Biophysics, Vanderbilt University, Nashville, TN, 37240, United States
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Sorkin ML, Tzeng SC, King S, Romanowski A, Kahle N, Bindbeutel R, Hiltbrunner A, Yanovsky MJ, Evans BS, Nusinow DA. COLD REGULATED GENE 27 and 28 Antagonize the Transcriptional Activity of the RVE8/LNK1/LNK2 Circadian Complex. Plant Physiol 2023:kiad210. [PMID: 37017001 DOI: 10.1093/plphys/kiad210] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/16/2022] [Revised: 03/01/2023] [Accepted: 04/04/2023] [Indexed: 06/19/2023]
Abstract
Many molecular and physiological processes in plants occur at a specific time of day. These daily rhythms are coordinated in part by the circadian clock, a timekeeper that uses daylength and temperature to maintain rhythms of approximately 24 hours in various clock-regulated phenotypes. The circadian MYB-like transcription factor REVEILLE 8 (RVE8) interacts with its transcriptional coactivators NIGHT LIGHT INDUCIBLE AND CLOCK REGULATED 1 (LNK1) and LNK2 to promote the expression of evening-phased clock genes and cold tolerance factors. While genetic approaches have commonly been used to discover connections within the clock and between clock elements and other pathways, here we used affinity purification coupled with mass spectrometry to identify time-of-day-specific protein interactors of the RVE8-LNK1/LNK2 complex in Arabidopsis (Arabidopsis thaliana). Among the interactors of RVE8/LNK1/LNK2 were COLD REGULATED GENE 27 (COR27) and COR28, which coprecipitated in an evening-specific manner. In addition to COR27 and COR28, we found an enrichment of temperature-related interactors that led us to establish a previously uncharacterized role for LNK1 and LNK2 in temperature entrainment of the clock. We established that RVE8, LNK1, and either COR27 or COR28 form a tripartite complex in yeast (Saccharomyces cerevisiae) and that the effect of this interaction in planta serves to antagonize transcriptional activation of RVE8 target genes, potentially through mediating RVE8 protein degradation in the evening. Together, these results illustrate how a proteomic approach can be used to identify time-of-day-specific protein interactions. Discovery of the RVE8-LNK-COR protein complex indicates a previously unknown regulatory mechanism for circadian and temperature signaling pathways.
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Affiliation(s)
- Maria L Sorkin
- Donald Danforth Plant Science Center, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | | | - Stefanie King
- Donald Danforth Plant Science Center, St. Louis, MO, USA
- Division of Biology and Biomedical Sciences, Washington University in St. Louis, St. Louis, MO, USA
| | - Andrés Romanowski
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
| | - Nikolai Kahle
- Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
| | | | - Andreas Hiltbrunner
- Institute of Biology II, Faculty of Biology, University of Freiburg, Freiburg, Germany
- Signalling Research Centres BIOSS and CIBSS, University of Freiburg, Freiburg, Germany
| | - Marcelo J Yanovsky
- Fundación Instituto Leloir, Instituto de Investigaciones Bioquímicas de Buenos Aires-Consejo Nacional de Investigaciones Científicas y Técnicas (CONICET), Buenos Aires, Argentina
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Shah NM, Jang HJ, Liang Y, Maeng JH, Tzeng SC, Wu A, Basri NL, Qu X, Fan C, Li A, Katz B, Li D, Xing X, Evans BS, Wang T. Pan-cancer analysis identifies tumor-specific antigens derived from transposable elements. Nat Genet 2023; 55:631-639. [PMID: 36973455 DOI: 10.1038/s41588-023-01349-3] [Citation(s) in RCA: 26] [Impact Index Per Article: 26.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2020] [Accepted: 02/23/2023] [Indexed: 03/29/2023]
Abstract
Cryptic promoters within transposable elements (TEs) can be transcriptionally reactivated in tumors to create new TE-chimeric transcripts, which can produce immunogenic antigens. We performed a comprehensive screen for these TE exaptation events in 33 TCGA tumor types, 30 GTEx adult tissues and 675 cancer cell lines, and identified 1,068 TE-exapted candidates with the potential to generate shared tumor-specific TE-chimeric antigens (TS-TEAs). Whole-lysate and HLA-pulldown mass spectrometry data confirmed that TS-TEAs are presented on the surface of cancer cells. In addition, we highlight tumor-specific membrane proteins transcribed from TE promoters that constitute aberrant epitopes on the extracellular surface of cancer cells. Altogether, we showcase the high pan-cancer prevalence of TS-TEAs and atypical membrane proteins that could potentially be therapeutically exploited and targeted.
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Affiliation(s)
- Nakul M Shah
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - H Josh Jang
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
- Department of Epigenetics, Van Andel Institute, Grand Rapids, MI, USA
| | - Yonghao Liang
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Ju Heon Maeng
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Angela Wu
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Noah L Basri
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Xuan Qu
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Changxu Fan
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Amy Li
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Benjamin Katz
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Daofeng Li
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | - Xiaoyun Xing
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA
| | | | - Ting Wang
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA.
- The Edison Family Center for Genome Sciences and Systems Biology, Washington University School of Medicine, St. Louis, MO, USA.
- McDonnell Genome Institute, Washington University School of Medicine, St. Louis, MO, USA.
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Shen T, Conway C, Rempfert KR, Kyle JE, Colby SM, Gaul DA, Habra H, Kong F, Bloodsworth KJ, Allen D, Evans BS, Du X, Fernandez FM, Metz TO, Fiehn O, Evans CR. The unknown lipids project: harmonized methods improve compound identification and data reproducibility in an inter-laboratory untargeted lipidomics study. bioRxiv 2023:2023.02.01.526566. [PMID: 36778509 PMCID: PMC9915661 DOI: 10.1101/2023.02.01.526566] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/09/2023]
Abstract
Untargeted lipidomics allows analysis of a broader range of lipids than targeted methods and permits discovery of unknown compounds. Previous ring trials have evaluated the reproducibility of targeted lipidomics methods, but inter-laboratory comparison of compound identification and unknown feature detection in untargeted lipidomics has not been attempted. To address this gap, five laboratories analyzed a set of mammalian tissue and biofluid reference samples using both their own untargeted lipidomics procedures and a common chromatographic and data analysis method. While both methods yielded informative data, the common method improved chromatographic reproducibility and resulted in detection of more shared features between labs. Spectral search against the LipidBlast in silico library enabled identification of over 2,000 unique lipids. Further examination of LC-MS/MS and ion mobility data, aided by hybrid search and spectral networking analysis, revealed spectral and chromatographic patterns useful for classification of unknown features, a subset of which were highly reproducible between labs. Overall, our method offers enhanced compound identification performance compared to targeted lipidomics, demonstrates the potential of harmonized methods to improve inter-site reproducibility for quantitation and feature alignment, and can serve as a reference to aid future annotation of untargeted lipidomics data.
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6
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Kim KQ, Burgute BD, Tzeng SC, Jing C, Jungers C, Zhang J, Yan LL, Vierstra RD, Djuranovic S, Evans BS, Zaher HS. N1-methylpseudouridine found within COVID-19 mRNA vaccines produces faithful protein products. Cell Rep 2022; 40:111300. [PMID: 35988540 PMCID: PMC9376333 DOI: 10.1016/j.celrep.2022.111300] [Citation(s) in RCA: 14] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/25/2021] [Revised: 06/07/2022] [Accepted: 08/10/2022] [Indexed: 11/24/2022] Open
Abstract
Synthetic mRNA technology is a promising avenue for treating and preventing disease. Key to the technology is the incorporation of modified nucleotides such as N1-methylpseudouridine (m1Ψ) to decrease immunogenicity of the RNA. However, relatively few studies have addressed the effects of modified nucleotides on the decoding process. Here, we investigate the effect of m1Ψ and the related modification pseudouridine (Ψ) on translation. In a reconstituted system, we find that m1Ψ does not significantly alter decoding accuracy. More importantly, we do not detect an increase in miscoded peptides when mRNA containing m1Ψ is translated in cell culture, compared with unmodified mRNA. We also find that m1Ψ does not stabilize mismatched RNA-duplex formation and only marginally promotes errors during reverse transcription. Overall, our results suggest that m1Ψ does not significantly impact translational fidelity, a welcome sign for future RNA therapeutics.
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Affiliation(s)
- Kyusik Q. Kim
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | | | | | - Crystal Jing
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Courtney Jungers
- Department of Cell Biology and Physiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | - Junya Zhang
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Liewei L. Yan
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Richard D. Vierstra
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA
| | - Sergej Djuranovic
- Department of Cell Biology and Physiology, Washington University in St. Louis School of Medicine, St. Louis, MO 63110, USA
| | | | - Hani S. Zaher
- Department of Biology, Washington University in St. Louis, St. Louis, MO 63130, USA,Corresponding author
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Verbyla KL, Kube PD, Evans BS. Commercial implementation of genomic selection in Tasmanian Atlantic salmon: Scheme evolution and validation. Evol Appl 2021; 15:631-644. [PMID: 35505884 PMCID: PMC9046822 DOI: 10.1111/eva.13304] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2021] [Revised: 09/09/2021] [Accepted: 09/10/2021] [Indexed: 11/30/2022] Open
Abstract
Genomic information was included for the first time in the prediction of breeding values for Atlantic salmon within the Australian Salmon Enterprises of Tasmania Pty Ltd selective breeding program in 2016. The process to realize genomic selection in the breeding program begun in 2014 with the scheme finalized and fully implemented for the first time in 2018. The high potential of within family selection to accelerate genetic gain, something not possible using the traditional pedigree‐based approach, provided the impetus for implementation. Efficient and effective genotyping platforms are essential for genomic selection. Genotype data from high density arrays revealed extensive persistence of linkage disequilibrium in the Tasmania Atlantic salmon population, resulting in high accuracies of both imputation and genomic breeding values when using imputed data. Consequently, a low‐density novel genotype‐by‐sequence assay was designed and incorporated into the scheme. Through the use of a static high‐ and dynamic low‐density genotyping platforms, an optimized genotyping scheme was devised and implemented such that all individuals in every year class are genotyped efficiently while maximizing the genetic gains and minimizing costs. The increase in the rates of genetic gain attributed to the implementation of genomic selection is significant across both the breeding programs primary and secondary traits. Substantial improvement in the ability to select parents prior to progeny testing is observed across multiple years. The resultant economic impacts for the industry are considerable based on the increases in genetic gain for traits achieved within the breeding program and the use of genomic selection for commercial production.
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8
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Rommelfanger S, Zhou M, Shaghasi H, Tzeng SC, Evans BS, Paša-Tolić L, Umen JG, Pesavento JJ. An Improved Top-Down Mass Spectrometry Characterization of Chlamydomonas reinhardtii Histones and Their Post-translational Modifications. J Am Soc Mass Spectrom 2021; 32:1671-1688. [PMID: 34165968 PMCID: PMC9236284 DOI: 10.1021/jasms.1c00029] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/24/2021] [Revised: 06/09/2021] [Accepted: 06/09/2021] [Indexed: 06/01/2023]
Abstract
We present an updated analysis of the linker and core histone proteins and their proteoforms in the green microalga Chlamydomonas reinhardtii by top-down mass spectrometry (TDMS). The combination of high-resolution liquid chromatographic separation, robust fragmentation, high mass spectral resolution, the application of a custom search algorithm, and extensive manual analysis enabled the characterization of 86 proteoforms across all four core histones H2A, H2B, H3, and H4 and the linker histone H1. All canonical H2A paralogs, which vary in their C-termini, were identified, along with the previously unreported noncanonical variant H2A.Z that had high levels of acetylation and C-terminal truncations. Similarly, a majority of the canonical H2B paralogs were identified, along with a smaller noncanonical variant, H2B.v1, that was highly acetylated. Histone H4 exhibited a novel acetylation profile that differs significantly from that found in other organisms. A majority of H3 was monomethylated at K4 with low levels of co-occuring acetylation, while a small fraction of H3 was trimethylated at K4 with high levels of co-occuring acetylation.
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Affiliation(s)
- Sarah
R. Rommelfanger
- Donald
Danforth Plant Science Center, St. Louis, Missouri 63132, United States
- Washington
University in St. Louis, St. Louis, Missouri 63130, United States
| | - Mowei Zhou
- Environmental
Molecular Sciences Laboratory, Pacific Northwest
National Laboratory, Richland, Washington 99354, United States
| | - Henna Shaghasi
- Saint
Mary’s College of California, Moraga, California 94575, United States
| | - Shin-Cheng Tzeng
- Donald
Danforth Plant Science Center, St. Louis, Missouri 63132, United States
| | - Bradley S. Evans
- Donald
Danforth Plant Science Center, St. Louis, Missouri 63132, United States
| | - Ljiljana Paša-Tolić
- Environmental
Molecular Sciences Laboratory, Pacific Northwest
National Laboratory, Richland, Washington 99354, United States
| | - James G. Umen
- Donald
Danforth Plant Science Center, St. Louis, Missouri 63132, United States
- Washington
University in St. Louis, St. Louis, Missouri 63130, United States
| | - James J. Pesavento
- Saint
Mary’s College of California, Moraga, California 94575, United States
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Shah NM, Jang HS, Maeng JH, Tzeng SC, Wu A, Fan C, Basri NL, Katz B, Li D, Xing X, Evans BS, Wang T. Abstract 2225: Transposable elements are an abundant and pan-cancer source of shared tumor-specific antigens and membrane targets. Cancer Res 2021. [DOI: 10.1158/1538-7445.am2021-2225] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/16/2022]
Abstract
Abstract
Transposable elements (TEs) represent close to half of the genome and are generally disregarded in genomic studies due to their silencing in somatic tissues and difficulty in mapping to their repetitive sequences. Recent studies have revealed that epigenetic dysregulation in cancer can unlock the regulatory potential of transposable elements (TEs), and they can play an important role in cancer progression and oncogenesis. One important consequence of this phenomenon is the pervasive activation of TEs' intrinsic promoters, which leads to generation of thousands of unique transcripts. Many of these transcripts splice into downstream genes and lead to the generation of TE-gene chimeric transcripts. These transcripts can alter the main reading frame of the original transcript to generate unique isoforms of the target gene or generate novel out-of-frame peptides that could be therapeutic targets. In this study, we analyzed the transcriptomes of 11,092 samples from 33 TCGA cancer types and 675 cancer cell lines to comprehensively profile all TE-gene fusion transcripts. Using somatic tissues from FANTOM5 and GTEx, we filtered these transcripts for tumor-specificity and discovered 2,642 tumor-specific TE-gene transcripts that promiscuously occur in nearly all TCGA tumor samples. Computational prediction of reading frames of these transcripts identified 1,202 candidates with the potential to generate tumor-specific TE-derived antigens (TS-TEAs). We further analyzed tumor mass spectrometry data from breast adenocarcinoma and ovarian cancer and confirmed that unique peptide sequences from TS-TEAs could be detected. In addition, we performed HLA-pulldown mass spectrometry and confirmed that TS-TEAs are presented on the cell surface in cancer cell lines. Given that these antigens are highly shared within and across cancer types, we assessed their potential to generate universal antigen-based therapies. Optimal combinations of 5, 10, and 20 TS-TEAs could generate unique peptides that bind to patient-specific HLA alleles for 39.2%, 50.8%, and 60.8% of all TCGA tumors respectively. Lastly, we highlight the tumor-specific membrane proteins transcribed from TE-exapted promoters that can potentially expose novel epitopes on the extracellular surface of cancer cells. These can be valuable targets of CAR-T or alternative antibody-based therapies. In conclusion, we showcase the high prevalence of TE-derived promoter activation in cancer and suggest multiple avenues by which this phenomenon can be targeted therapeutically.
Citation Format: Nakul M. Shah, Hyo Sik Jang, Ju Heon Maeng, Shin-Cheng Tzeng, Angela Wu, Changxu Fan, Noah L. Basri, Benjamin Katz, Daofeng Li, Xiaoyun Xing, Bradley S. Evans, Ting Wang. Transposable elements are an abundant and pan-cancer source of shared tumor-specific antigens and membrane targets [abstract]. In: Proceedings of the American Association for Cancer Research Annual Meeting 2021; 2021 Apr 10-15 and May 17-21. Philadelphia (PA): AACR; Cancer Res 2021;81(13_Suppl):Abstract nr 2225.
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Affiliation(s)
- Nakul M. Shah
- 1Washington University School of Medicine, St Louis, MO
| | - Hyo Sik Jang
- 1Washington University School of Medicine, St Louis, MO
| | - Ju Heon Maeng
- 1Washington University School of Medicine, St Louis, MO
| | | | - Angela Wu
- 1Washington University School of Medicine, St Louis, MO
| | - Changxu Fan
- 1Washington University School of Medicine, St Louis, MO
| | - Noah L. Basri
- 1Washington University School of Medicine, St Louis, MO
| | - Benjamin Katz
- 1Washington University School of Medicine, St Louis, MO
| | - Daofeng Li
- 1Washington University School of Medicine, St Louis, MO
| | - Xiaoyun Xing
- 1Washington University School of Medicine, St Louis, MO
| | | | - Ting Wang
- 1Washington University School of Medicine, St Louis, MO
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10
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Nam JW, Jenkins LM, Li J, Evans BS, Jaworski JG, Allen DK. A General Method for Quantification and Discovery of Acyl Groups Attached to Acyl Carrier Proteins in Fatty Acid Metabolism Using LC-MS/MS. Plant Cell 2020; 32:820-832. [PMID: 32060179 PMCID: PMC7145485 DOI: 10.1105/tpc.19.00954] [Citation(s) in RCA: 14] [Impact Index Per Article: 3.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 12/09/2019] [Revised: 02/03/2020] [Accepted: 02/12/2020] [Indexed: 06/10/2023]
Abstract
Acyl carrier proteins (ACPs) are the scaffolds for fatty acid biosynthesis in living systems, rendering them essential to a comprehensive understanding of lipid metabolism. However, accurate quantitative methods to assess individual acyl-ACPs do not exist. We developed a robust method to quantify acyl-ACPs to the picogram level. We successfully identified acyl-ACP elongation intermediates (3-hydroxyacyl-ACPs and 2,3-trans-enoyl-ACPs) and unexpected medium-chain (C10:1, C14:1) and polyunsaturated long-chain (C16:3) acyl-ACPs, indicating both the sensitivity of the method and how current descriptions of lipid metabolism and ACP function are incomplete. Such ACPs are likely important to medium-chain lipid production for fuels and highlight poorly understood lipid remodeling events in the chloroplast. The approach is broadly applicable to type II fatty acid synthase systems found in plants and bacteria as well as mitochondria from mammals and fungi because it capitalizes on a highly conserved Asp-Ser-Leu-Asp amino acid sequence in ACPs to which acyl groups attach. Our method allows for sensitive quantification using liquid chromatography-tandem mass spectrometry with de novo-generated standards and an isotopic dilution strategy and will fill a gap in our understanding, providing insights through quantitative exploration of fatty acid biosynthesis processes for optimal biofuels, renewable feedstocks, and medical studies in health and disease.
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Affiliation(s)
- Jeong-Won Nam
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, Missouri 63132
| | - Lauren M Jenkins
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, Missouri 63132
- USDA-ARS, Plant Genetics Research Unit, 975 North Warson Road, St. Louis, Missouri 63132
| | - Jia Li
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, Missouri 63132
| | - Bradley S Evans
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, Missouri 63132
| | - Jan G Jaworski
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, Missouri 63132
| | - Doug K Allen
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, Missouri 63132
- USDA-ARS, Plant Genetics Research Unit, 975 North Warson Road, St. Louis, Missouri 63132
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11
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North JA, Wildenthal JA, Erb TJ, Evans BS, Byerly KM, Gerlt JA, Tabita FR. A bifunctional salvage pathway for two distinct S-adenosylmethionine by-products that is widespread in bacteria, including pathogenic Escherichia coli. Mol Microbiol 2020; 113:923-937. [PMID: 31950558 DOI: 10.1111/mmi.14459] [Citation(s) in RCA: 15] [Impact Index Per Article: 3.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/10/2019] [Revised: 01/08/2020] [Accepted: 01/12/2020] [Indexed: 01/19/2023]
Abstract
S-adenosyl-l-methionine (SAM) is a necessary cosubstrate for numerous essential enzymatic reactions including protein and nucleotide methylations, secondary metabolite synthesis and radical-mediated processes. Radical SAM enzymes produce 5'-deoxyadenosine, and SAM-dependent enzymes for polyamine, neurotransmitter and quorum sensing compound synthesis produce 5'-methylthioadenosine as by-products. Both are inhibitory and must be addressed by all cells. This work establishes a bifunctional oxygen-independent salvage pathway for 5'-deoxyadenosine and 5'-methylthioadenosine in both Rhodospirillum rubrum and Extraintestinal Pathogenic Escherichia coli. Homologous genes for this pathway are widespread in bacteria, notably pathogenic strains within several families. A phosphorylase (Rhodospirillum rubrum) or separate nucleoside and kinase (Escherichia coli) followed by an isomerase and aldolase sequentially function to salvage these two wasteful and inhibitory compounds into adenine, dihydroxyacetone phosphate and acetaldehyde or (2-methylthio)acetaldehyde during both aerobic and anaerobic growth. Both SAM by-products are metabolized with equal affinity during aerobic and anaerobic growth conditions, suggesting that the dual-purpose salvage pathway plays a central role in numerous environments, notably the human body during infection. Our newly discovered bifunctional oxygen-independent pathway, widespread in bacteria, salvages at least two by-products of SAM-dependent enzymes for carbon and sulfur salvage, contributing to cell growth.
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Affiliation(s)
- Justin A North
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
| | - John A Wildenthal
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
| | - Tobias J Erb
- Department of Biochemistry and Synthetic Metabolism, Max Planck Institute for Terrestrial Microbiology, Marburg, Germany
| | - Bradley S Evans
- The Donald Danforth Plant Science Center, St. Louis, MO, USA
| | - Kathryn M Byerly
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
| | - John A Gerlt
- Department of Biochemistry, The Institute for Genomic Biology, Champaign, IL, USA.,Department of Chemistry, University of Illinois at Urbana-Champaign, Champaign, IL, USA
| | - Fred R Tabita
- Department of Microbiology, The Ohio State University, Columbus, OH, USA
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12
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Kambhampati S, Li J, Evans BS, Allen DK. Accurate and efficient amino acid analysis for protein quantification using hydrophilic interaction chromatography coupled tandem mass spectrometry. Plant Methods 2019; 15:46. [PMID: 31110556 PMCID: PMC6511150 DOI: 10.1186/s13007-019-0430-z] [Citation(s) in RCA: 46] [Impact Index Per Article: 9.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/12/2019] [Accepted: 04/25/2019] [Indexed: 05/12/2023]
Abstract
BACKGROUND Methods used to quantify protein from biological samples are often inaccurate with significant variability that requires care to minimize. The errors result from losses during protein preparation and purification and false detection of interfering compounds or elements. Amino acid analysis (AAA) involves a series of chromatographic techniques that can be used to measure protein levels, avoiding some difficulties and providing specific compositional information. However, unstable derivatives, that are toxic and can be costly, incomplete reactions, inadequate chromatographic separations, and the lack of a single hydrolysis method with sufficient recovery of all amino acids hinder precise protein quantitation using AAA. RESULTS In this study, a hydrophilic interaction chromatography based method was used to separate all proteinogenic amino acids, including isobaric compounds leucine and isoleucine, prior to detection by multiple reaction monitoring with LC-MS/MS. Through inclusion of commercially available isotopically labeled (13C, 15N) amino acids as internal standards we adapted an isotopic dilution strategy for amino acid-based quantification of proteins. Three hydrolysis methods were tested with ubiquitin, bovine serum albumin, (BSA), and a soy protein biological reference material (SRM 3234; NIST) resulting in protein estimates that were 86-103%, 82-94%, and 90-99% accurate for the three protein samples respectively. The methane sulfonic acid hydrolysis approach provided the best recovery of labile amino acids including: cysteine, methionine and tryptophan that are challenging to accurately quantify. CONCLUSIONS Accurate determination of protein quantity and amino acid composition in heterogeneous biological samples is non-trivial. Recent advances in chromatographic phases and LC-MS/MS based methods, along with the availability of isotopic standards can minimize difficulties in analysis and improve protein quantitation. A robust method is described for high-throughput protein quantification and amino acid compositional analysis. Since accurate measurement of protein quality and quantity are a requirement for many biological studies that relate to crop improvement or more generally, our understanding of metabolism in living systems, we envision this method will have broad applicability.
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Affiliation(s)
| | - Jia Li
- Donald Danforth Plant Science Center, St. Louis, MO USA
| | | | - Doug K. Allen
- Donald Danforth Plant Science Center, St. Louis, MO USA
- United States Department of Agriculture, Agricultural Research Service, St. Louis, MO USA
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13
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Huang H, Gehan MA, Huss SE, Alvarez S, Lizarraga C, Gruebbling EL, Gierer J, Naldrett MJ, Bindbeutel RK, Evans BS, Mockler TC, Nusinow DA. Cross-species complementation reveals conserved functions for EARLY FLOWERING 3 between monocots and dicots. Plant Direct 2017; 1:e00018. [PMID: 31245666 PMCID: PMC6508535 DOI: 10.1002/pld3.18] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/24/2017] [Revised: 08/10/2017] [Accepted: 09/13/2017] [Indexed: 05/03/2023]
Abstract
Plant responses to the environment are shaped by external stimuli and internal signaling pathways. In both the model plant Arabidopsis thaliana (Arabidopsis) and crop species, circadian clock factors are critical for growth, flowering, and circadian rhythms. Outside of Arabidopsis, however, little is known about the molecular function of clock gene products. Therefore, we sought to compare the function of Brachypodium distachyon (Brachypodium) and Setaria viridis (Setaria) orthologs of EARLY FLOWERING 3, a key clock gene in Arabidopsis. To identify both cycling genes and putative ELF3 functional orthologs in Setaria, a circadian RNA-seq dataset and online query tool (Diel Explorer) were generated to explore expression profiles of Setaria genes under circadian conditions. The function of ELF3 orthologs from Arabidopsis, Brachypodium, and Setaria was tested for complementation of an elf3 mutation in Arabidopsis. We find that both monocot orthologs were capable of rescuing hypocotyl elongation, flowering time, and arrhythmic clock phenotypes. Using affinity purification and mass spectrometry, our data indicate that BdELF3 and SvELF3 could be integrated into similar complexes in vivo as AtELF3. Thus, we find that, despite 180 million years of separation, BdELF3 and SvELF3 can functionally complement loss of ELF3 at the molecular and physiological level.
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Affiliation(s)
- He Huang
- Donald Danforth Plant Science CenterSt. LouisMOUSA
| | | | | | - Sophie Alvarez
- Donald Danforth Plant Science CenterSt. LouisMOUSA
- Present address:
University of Nebraska‐LincolnLincolnNEUSA
| | | | | | - John Gierer
- Donald Danforth Plant Science CenterSt. LouisMOUSA
| | - Michael J. Naldrett
- Donald Danforth Plant Science CenterSt. LouisMOUSA
- Present address:
University of Nebraska‐LincolnLincolnNEUSA
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14
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Couso I, Evans BS, Li J, Liu Y, Ma F, Diamond S, Allen DK, Umen JG. Synergism between Inositol Polyphosphates and TOR Kinase Signaling in Nutrient Sensing, Growth Control, and Lipid Metabolism in Chlamydomonas. Plant Cell 2016; 28:2026-2042. [PMID: 27600537 PMCID: PMC5059802 DOI: 10.1105/tpc.16.00351] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/03/2016] [Revised: 08/19/2016] [Accepted: 09/02/2016] [Indexed: 05/17/2023]
Abstract
The networks that govern carbon metabolism and control intracellular carbon partitioning in photosynthetic cells are poorly understood. Target of Rapamycin (TOR) kinase is a conserved growth regulator that integrates nutrient signals and modulates cell growth in eukaryotes, though the TOR signaling pathway in plants and algae has yet to be completely elucidated. We screened the unicellular green alga Chlamydomonas reinhardtii using insertional mutagenesis to find mutants that conferred hypersensitivity to the TOR inhibitor rapamycin. We characterized one mutant, vip1-1, that is predicted to encode a conserved inositol hexakisphosphate kinase from the VIP family that pyrophosphorylates phytic acid (InsP6) to produce the low abundance signaling molecules InsP7 and InsP8 Unexpectedly, the rapamycin hypersensitive growth arrest of vip1-1 cells was dependent on the presence of external acetate, which normally has a growth-stimulatory effect on Chlamydomonas. vip1-1 mutants also constitutively overaccumulated triacylglycerols (TAGs) in a manner that was synergistic with other TAG inducing stimuli such as starvation. vip1-1 cells had reduced InsP7 and InsP8, both of which are dynamically modulated in wild-type cells by TOR kinase activity and the presence of acetate. Our data uncover an interaction between the TOR kinase and inositol polyphosphate signaling systems that we propose governs carbon metabolism and intracellular pathways that lead to storage lipid accumulation.
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Affiliation(s)
| | - Bradley S Evans
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Jia Li
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Yu Liu
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Fangfang Ma
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
| | - Spencer Diamond
- Earth and Planetary Science, University of California, Berkeley, California 94720
| | - Doug K Allen
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
- Agricultural Research Service, U.S. Department of Agriculture, St. Louis, Missouri 63132
| | - James G Umen
- Donald Danforth Plant Science Center, St. Louis, Missouri 63132
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15
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Huang H, Yoo CY, Bindbeutel R, Goldsworthy J, Tielking A, Alvarez S, Naldrett MJ, Evans BS, Chen M, Nusinow DA. PCH1 integrates circadian and light-signaling pathways to control photoperiod-responsive growth in Arabidopsis. eLife 2016; 5:e13292. [PMID: 26839287 PMCID: PMC4755757 DOI: 10.7554/elife.13292] [Citation(s) in RCA: 59] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/24/2015] [Accepted: 01/13/2016] [Indexed: 01/06/2023] Open
Abstract
Plants react to seasonal change in day length through altering physiology and development. Factors that function to harmonize growth with photoperiod are poorly understood. Here we characterize a new protein that associates with both circadian clock and photoreceptor components, named PHOTOPERIODIC CONTROL OF HYPOCOTYL1 (PCH1). pch1 seedlings have overly elongated hypocotyls specifically under short days while constitutive expression of PCH1 shortens hypocotyls independent of day length. PCH1 peaks at dusk, binds phytochrome B (phyB) in a red light-dependent manner, and co-localizes with phyB into photobodies. PCH1 is necessary and sufficient to promote the biogenesis of large photobodies to maintain an active phyB pool after light exposure, potentiating red-light signaling and prolonging memory of prior illumination. Manipulating PCH1 alters PHYTOCHROME INTERACTING FACTOR 4 levels and regulates light-responsive gene expression. Thus, PCH1 is a new factor that regulates photoperiod-responsive growth by integrating the clock with light perception pathways through modulating daily phyB-signaling. DOI:http://dx.doi.org/10.7554/eLife.13292.001 Most living things possess an internal “circadian” clock that synchronizes many behaviors, such as eating, resting or growing, with the day-night cycle. With the help of proteins that can detect light, known as photoreceptors, the clock also coordinates these behaviors as the number of daylight hours changes during the year. However, it is not known how the clock and photoreceptors are able to work together. The circadian clocks of animals and plants have evolved separately and use different proteins. In plants, a photoreceptor called phytochrome B responds to red light and regulates the ability of plants to grow. Most plants harness sunlight during the day, but grow fastest in the dark just before dawn. In 2015, researchers identified a new protein in a plant called Arabidopsis that is associated with several plant clock proteins and photoreceptors, including phytochrome B. However, the role of this new protein was not clear. Now, Huang et al. – including many of the researchers from the 2015 work – studied the new protein, named PCH1, in more detail. The experiments show that PCH1 is a critical link that regulates the daily growth of Arabidopsis plants in response to the number of daylight hours. PCH1 stabilizes the structure of phytochrome B so that it remains active, even in the dark. This prolonged activity acts as a molecular memory of prior exposure to light and helps to prevent plants from growing too much in the winter when there are fewer hours of daylight. Since PCH1 is also found in other species of plants, it may play the same role in regulating growth of major crop plants. The next challenge is to understand how the binding of PCH1 to phytochrome B alters the photoreceptor’s activity. In the future, Huang et al. hope to find out if manipulating the activity of PCH1 can improve the growth of crops in places where there is a large change in day length across the seasons. DOI:http://dx.doi.org/10.7554/eLife.13292.002
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Affiliation(s)
- He Huang
- Donald Danforth Plant Science Center, St. Louis, United States
| | - Chan Yul Yoo
- Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California at Riverside, Riverside, United States
| | | | | | - Allison Tielking
- Mary Institute and Saint Louis Country Day School, St. Louis, United States
| | - Sophie Alvarez
- Donald Danforth Plant Science Center, St. Louis, United States
| | | | - Bradley S Evans
- Donald Danforth Plant Science Center, St. Louis, United States
| | - Meng Chen
- Department of Botany and Plant Sciences, Institute of Integrative Genome Biology, University of California at Riverside, Riverside, United States
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16
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Huang H, Alvarez S, Bindbeutel R, Shen Z, Naldrett MJ, Evans BS, Briggs SP, Hicks LM, Kay SA, Nusinow DA. Identification of Evening Complex Associated Proteins in Arabidopsis by Affinity Purification and Mass Spectrometry. Mol Cell Proteomics 2016; 15:201-217. [PMID: 26545401 DOI: 10.6019/pxd002606] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Indexed: 05/21/2023] Open
Abstract
Many species possess an endogenous circadian clock to synchronize internal physiology with an oscillating external environment. In plants, the circadian clock coordinates growth, metabolism and development over daily and seasonal time scales. Many proteins in the circadian network form oscillating complexes that temporally regulate myriad processes, including signal transduction, transcription, protein degradation and post-translational modification. In Arabidopsis thaliana, a tripartite complex composed of EARLY FLOWERING 4 (ELF4), EARLY FLOWERING 3 (ELF3), and LUX ARRHYTHMO (LUX), named the evening complex, modulates daily rhythms in gene expression and growth through transcriptional regulation. However, little is known about the physical interactions that connect the circadian system to other pathways. We used affinity purification and mass spectrometry (AP-MS) methods to identify proteins that associate with the evening complex in A. thaliana. New connections within the circadian network as well as to light signaling pathways were identified, including linkages between the evening complex, TIMING OF CAB EXPRESSION1 (TOC1), TIME FOR COFFEE (TIC), all phytochromes and TANDEM ZINC KNUCKLE/PLUS3 (TZP). Coupling genetic mutation with affinity purifications tested the roles of phytochrome B (phyB), EARLY FLOWERING 4, and EARLY FLOWERING 3 as nodes connecting the evening complex to clock and light signaling pathways. These experiments establish a hierarchical association between pathways and indicate direct and indirect interactions. Specifically, the results suggested that EARLY FLOWERING 3 and phytochrome B act as hubs connecting the clock and red light signaling pathways. Finally, we characterized a clade of associated nuclear kinases that regulate circadian rhythms, growth, and flowering in A. thaliana. Coupling mass spectrometry and genetics is a powerful method to rapidly and directly identify novel components and connections within and between complex signaling pathways.
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Affiliation(s)
- He Huang
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Sophie Alvarez
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Rebecca Bindbeutel
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Zhouxin Shen
- §University of California San Diego, Division of Biological Sciences, Cell and Developmental Biology Section, 9500 Gilman Drive, La Jolla, California 92093-0116
| | - Michael J Naldrett
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Bradley S Evans
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Steven P Briggs
- §University of California San Diego, Division of Biological Sciences, Cell and Developmental Biology Section, 9500 Gilman Drive, La Jolla, California 92093-0116
| | - Leslie M Hicks
- ¶The University of North Carolina at Chapel Hill, Department of Chemistry, Chapel Hill, North Carolina 27599
| | - Steve A Kay
- ‖University of Southern California, Molecular and Computational Biology Section, Los Angeles, California 90089
| | - Dmitri A Nusinow
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132;
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17
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Huang H, Alvarez S, Bindbeutel R, Shen Z, Naldrett MJ, Evans BS, Briggs SP, Hicks LM, Kay SA, Nusinow DA. Identification of Evening Complex Associated Proteins in Arabidopsis by Affinity Purification and Mass Spectrometry. Mol Cell Proteomics 2015; 15:201-17. [PMID: 26545401 PMCID: PMC4762519 DOI: 10.1074/mcp.m115.054064] [Citation(s) in RCA: 120] [Impact Index Per Article: 13.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2015] [Indexed: 11/30/2022] Open
Abstract
Many species possess an endogenous circadian clock to synchronize internal physiology with an oscillating external environment. In plants, the circadian clock coordinates growth, metabolism and development over daily and seasonal time scales. Many proteins in the circadian network form oscillating complexes that temporally regulate myriad processes, including signal transduction, transcription, protein degradation and post-translational modification. In Arabidopsis thaliana, a tripartite complex composed of EARLY FLOWERING 4 (ELF4), EARLY FLOWERING 3 (ELF3), and LUX ARRHYTHMO (LUX), named the evening complex, modulates daily rhythms in gene expression and growth through transcriptional regulation. However, little is known about the physical interactions that connect the circadian system to other pathways. We used affinity purification and mass spectrometry (AP-MS) methods to identify proteins that associate with the evening complex in A. thaliana. New connections within the circadian network as well as to light signaling pathways were identified, including linkages between the evening complex, TIMING OF CAB EXPRESSION1 (TOC1), TIME FOR COFFEE (TIC), all phytochromes and TANDEM ZINC KNUCKLE/PLUS3 (TZP). Coupling genetic mutation with affinity purifications tested the roles of phytochrome B (phyB), EARLY FLOWERING 4, and EARLY FLOWERING 3 as nodes connecting the evening complex to clock and light signaling pathways. These experiments establish a hierarchical association between pathways and indicate direct and indirect interactions. Specifically, the results suggested that EARLY FLOWERING 3 and phytochrome B act as hubs connecting the clock and red light signaling pathways. Finally, we characterized a clade of associated nuclear kinases that regulate circadian rhythms, growth, and flowering in A. thaliana. Coupling mass spectrometry and genetics is a powerful method to rapidly and directly identify novel components and connections within and between complex signaling pathways.
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Affiliation(s)
- He Huang
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Sophie Alvarez
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Rebecca Bindbeutel
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Zhouxin Shen
- §University of California San Diego, Division of Biological Sciences, Cell and Developmental Biology Section, 9500 Gilman Drive, La Jolla, California 92093-0116
| | - Michael J Naldrett
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Bradley S Evans
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132
| | - Steven P Briggs
- §University of California San Diego, Division of Biological Sciences, Cell and Developmental Biology Section, 9500 Gilman Drive, La Jolla, California 92093-0116
| | - Leslie M Hicks
- ¶The University of North Carolina at Chapel Hill, Department of Chemistry, Chapel Hill, North Carolina 27599
| | - Steve A Kay
- ‖University of Southern California, Molecular and Computational Biology Section, Los Angeles, California 90089
| | - Dmitri A Nusinow
- From the ‡Donald Danforth Plant Science Center, 975 N. Warson Road, St. Louis, Missouri, 63132;
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18
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Dey S, North JA, Sriram J, Evans BS, Tabita FR. In Vivo Studies in Rhodospirillum rubrum Indicate That Ribulose-1,5-bisphosphate Carboxylase/Oxygenase (Rubisco) Catalyzes Two Obligatorily Required and Physiologically Significant Reactions for Distinct Carbon and Sulfur Metabolic Pathways. J Biol Chem 2015; 290:30658-68. [PMID: 26511314 DOI: 10.1074/jbc.m115.691295] [Citation(s) in RCA: 19] [Impact Index Per Article: 2.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2015] [Indexed: 12/19/2022] Open
Abstract
All organisms possess fundamental metabolic pathways to ensure that needed carbon and sulfur compounds are provided to the cell in the proper chemical form and oxidation state. For most organisms capable of using CO2 as sole source of carbon, ribulose-1,5-bisphosphate (RuBP) carboxylase/oxygenase (Rubisco) catalyzes primary carbon dioxide assimilation. In addition, sulfur salvage pathways are necessary to ensure that key sulfur-containing compounds are both available and, where necessary, detoxified in the cell. Using knock-out mutations and metabolomics in the bacterium Rhodospirillum rubrum, we show here that Rubisco concurrently catalyzes key and essential reactions for seemingly unrelated but physiologically essential central carbon and sulfur salvage metabolic pathways of the cell. In this study, complementation and mutagenesis studies indicated that representatives of all known extant functional Rubisco forms found in nature are capable of simultaneously catalyzing reactions required for both CO2-dependent growth as well as growth using 5-methylthioadenosine as sole sulfur source under anaerobic photosynthetic conditions. Moreover, specific inactivation of the CO2 fixation reaction did not affect the ability of Rubisco to support anaerobic 5-methylthioadenosine metabolism, suggesting that the active site of Rubisco has evolved to ensure that this enzyme maintains both key functions. Thus, despite the coevolution of both functions, the active site of this protein may be differentially modified to affect only one of its key functions.
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Affiliation(s)
- Swati Dey
- From the Department of Microbiology, The Ohio State University, Columbus, Ohio 43210 and
| | - Justin A North
- From the Department of Microbiology, The Ohio State University, Columbus, Ohio 43210 and
| | - Jaya Sriram
- From the Department of Microbiology, The Ohio State University, Columbus, Ohio 43210 and
| | - Bradley S Evans
- the Donald Danforth Plant Science Center, St. Louis, Missouri, 63132
| | - F Robert Tabita
- From the Department of Microbiology, The Ohio State University, Columbus, Ohio 43210 and
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19
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Augustin MM, Ruzicka DR, Shukla AK, Augustin JM, Starks CM, O’Neil-Johnson M, McKain MR, Evans BS, Barrett MD, Smithson A, Wong GKS, Deyholos MK, Edger PP, Pires JC, Leebens-Mack JH, Mann DA, Kutchan TM. Elucidating steroid alkaloid biosynthesis in Veratrum californicum: production of verazine in Sf9 cells. Plant J 2015; 82:991-1003. [PMID: 25939370 PMCID: PMC4464957 DOI: 10.1111/tpj.12871] [Citation(s) in RCA: 24] [Impact Index Per Article: 2.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/28/2014] [Revised: 04/15/2015] [Accepted: 04/24/2015] [Indexed: 05/05/2023]
Abstract
Steroid alkaloids have been shown to elicit a wide range of pharmacological effects that include anticancer and antifungal activities. Understanding the biosynthesis of these molecules is essential to bioengineering for sustainable production. Herein, we investigate the biosynthetic pathway to cyclopamine, a steroid alkaloid that shows promising antineoplastic activities. Supply of cyclopamine is limited, as the current source is solely derived from wild collection of the plant Veratrum californicum. To elucidate the early stages of the pathway to cyclopamine, we interrogated a V. californicum RNA-seq dataset using the cyclopamine accumulation profile as a predefined model for gene expression with the pattern-matching algorithm Haystack. Refactoring candidate genes in Sf9 insect cells led to discovery of four enzymes that catalyze the first six steps in steroid alkaloid biosynthesis to produce verazine, a predicted precursor to cyclopamine. Three of the enzymes are cytochromes P450 while the fourth is a γ-aminobutyrate transaminase; together they produce verazine from cholesterol.
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Affiliation(s)
| | - Dan R. Ruzicka
- Donald Danforth Plant Science Center, St. Louis, Missouri, USA
- Monsanto Company, 700 Chesterfield Parkway West, St Louis, MO 63017
| | - Ashutosh K. Shukla
- Donald Danforth Plant Science Center, St. Louis, Missouri, USA
- CSIR-Central Institute of Medicinal and Aromatic Plants, P.O. CIMAP, Lucknow 226015, Uttar Pradesh, India
| | | | | | | | | | | | - Matt D. Barrett
- Botanic Gardens and Parks Authority Kings Park and Botanic Garden, West Perth, Australia
- School of Plant Biology, University of Western Australia, Perth, Australia
| | - Ann Smithson
- Botanic Gardens and Parks Authority Kings Park and Botanic Garden, West Perth, Australia
- School of Plant Biology, University of Western Australia, Perth, Australia
| | - Gane Ka-Shu Wong
- Department of Biological Sciences, University of Alberta, Edmonton AB, Canada
- Department of Medicine, University of Alberta, Edmonton AB, Canada
- BGI-Shenzhen, Beishan Industrial Zone, Yantian District, Shenzhen, China
| | | | - Patrick P. Edger
- Bond Life Sciences Center, Division of Biological Sciences, University of Missouri, Columbia, Missouri, USA
- Department of Plant and Microbial Biology, University of California, Berkeley, California, USA
| | - J. Chris Pires
- Bond Life Sciences Center, Division of Biological Sciences, University of Missouri, Columbia, Missouri, USA
| | | | - David A. Mann
- Infinity Pharmaceuticals, Cambridge, Massachusetts, USA
- Cellular Dynamics International, 525 Science Drive, Madison, WI 53711
| | - Toni M. Kutchan
- Donald Danforth Plant Science Center, St. Louis, Missouri, USA
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20
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Abstract
Engineering metabolic biosynthetic pathways has enabled the microbial production of many useful chemicals. However, pathway productivities and yields are often limited by metabolic imbalances. Synthetic regulatory circuits have been shown to be able to balance engineered pathways, improving titers and productivities. Here we developed a negative feedback regulatory circuit based on a malonyl-CoA-based sensor-actuator. Malonyl-CoA is biosynthesized from acetyl-CoA by the acetyl-CoA carboxylase, which is the rate-limiting step for fatty acid biosynthesis. Overexpression of acetyl-CoA carboxylase improves fatty acid production, but slows down cell growth. We have devised a malonyl-CoA sensor-actuator that controls gene expression levels based on intracellular malonyl-CoA concentrations. This sensor-actuator is used to construct a negative feedback circuit to regulate the expression of acetyl-CoA carboxylase. The negative feedback circuit is able to up-regulate acetyl-CoA carboxylase expression when the malonyl-CoA concentration is low and down-regulate acetyl-CoA carboxylase expression when excess amounts of malonyl-CoA have accumulated. We show that the regulatory circuit effectively alleviates the toxicity associated with acetyl-CoA carboxylase overexpression. When used to regulate the fatty acid pathway, the feedback circuit increases fatty acid titer and productivity by 34% and 33%, respectively.
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Affiliation(s)
- Di Liu
- Department
of Energy, Environmental and Chemical Engineering, Washington University, 1 Brookings Drive, St. Louis, Missouri 63130, United States
| | - Yi Xiao
- Department
of Energy, Environmental and Chemical Engineering, Washington University, 1 Brookings Drive, St. Louis, Missouri 63130, United States
| | - Bradley S. Evans
- Donald Danforth Plant Science Center, 975 North Warson Road, St. Louis, Missouri 63132, United States
| | - Fuzhong Zhang
- Department
of Energy, Environmental and Chemical Engineering, Washington University, 1 Brookings Drive, St. Louis, Missouri 63130, United States
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21
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Abstract
While recent advances in metabolomic measurement technologies have been dramatic, extracting biological insight from complex metabolite profiles remains a challenge. We present an analytical strategy that uses data obtained from high resolution liquid chromatography-mass spectrometry and a bioinformatics toolset for detecting actively changing metabolic pathways upon external perturbation. We begin with untargeted metabolite profiling to nominate altered metabolites and identify pathway candidates, followed by validation of those pathways with transcriptomics. Using the model organisms Rhodospirillum rubrum and Bacillus subtilis, our results reveal metabolic pathways that are interconnected with methionine salvage. The rubrum-type methionine salvage pathway is interconnected with the active methyl cycle in which re-methylation, a key reaction for recycling methionine from homocysteine, is unexpectedly suppressed; instead, homocysteine is catabolized by the transsulfuration pathway. Notably, the non-mevalonate pathway is repressed, whereas the rubrum-type methionine salvage pathway contributes to isoprenoid biosynthesis upon 5'-methylthioadenosine feeding. In this process, glutathione functions as a coenzyme in vivo when 1-methylthio-d-xylulose 5-phosphate (MTXu 5-P) methylsulfurylase catalyzes dethiomethylation of MTXu 5-P. These results clearly show that our analytical approach enables unexpected metabolic pathways to be uncovered.
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Affiliation(s)
- Kyuil Cho
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL 61801 USA
| | - Bradley S. Evans
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL 61801 USA
| | - B. McKay Wood
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Ritesh Kumar
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Tobias J. Erb
- Institute for Microbiology, Swiss Federal Institute of Technology (ETH) Zurich, CH-8093 Zurich, Switzerland
| | - Benjamin P. Warlick
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - John A. Gerlt
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL 61801 USA
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
| | - Jonathan V. Sweedler
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, Urbana, IL 61801 USA
- Department of Chemistry, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL 61801 USA
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22
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Abstract
Phenotype in multicellular organisms is the consequence of dynamic metabolic events that occur in a spatially dependent fashion. This spatial and temporal complexity presents challenges for investigating metabolism; creating a need for improved methods that effectively probe biochemical events such as amino acid biosynthesis. Isotopic labeling can provide a temporal-spatial recording of metabolic events through, for example, the description of enriched amino acids in the protein pool. Proteins are therefore an important readout of metabolism and can be assessed with modern mass spectrometers. We compared the measurement of isotopic labeling in MS2 spectra obtained from tandem mass spectrometry under either higher energy collision dissociation (HCD) or collision induced dissociation (CID) at varied energy levels. Developing soybean embryos cultured with or without 13C-labeled substrates, and Escherichia coli MG1655 enriched by feeding 7% uniformly labeled glucose served as a source of biological material for protein evaluation. CID with low energies resulted in a disproportionate amount of heavier isotopologues remaining in the precursor isotopic distribution. HCD resulted in fewer quantifiable products; however deviation from predicted distributions were small relative to the CID-based comparisons. Fragment ions have the potential to provide information on the labeling of amino acids in peptides, but our results indicate that without further development the use of this readout in quantitative methods such as metabolic flux analysis is limited.
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Affiliation(s)
- Doug K. Allen
- United States Department of Agriculture, Agricultural Research Service, Plant Genetic Research Unit, St. Louis, Missouri, United States of America
- Donald Danforth Plant Science Center, St. Louis, Missouri, United States of America
| | - Bradley S. Evans
- Donald Danforth Plant Science Center, St. Louis, Missouri, United States of America
| | - Igor G. L. Libourel
- Department of Plant Biology, University of Minnesota, St. Paul, Minnesota, United States of America
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23
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Cioni JP, Doroghazi J, Ju KS, Yu X, Evans BS, Lee J, Metcalf WW. Cyanohydrin phosphonate natural product from Streptomyces regensis. J Nat Prod 2014; 77:243-249. [PMID: 24437999 PMCID: PMC3993929 DOI: 10.1021/np400722m] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Figures] [Subscribe] [Scholar Register] [Received: 09/05/2013] [Indexed: 06/03/2023]
Abstract
Streptomyces regensis strain WC-3744 was identified as a potential phosphonic acid producer in a large-scale screen of microorganisms for the presence of the pepM gene, which encodes the key phosphonate biosynthetic enzyme phosphoenolpyruvate phosphonomutase. (31)P NMR revealed the presence of several unidentified phosphonates in spent medium after growth of S. regensis. These compounds were purified and structurally characterized via extensive 1D and 2D NMR spectroscopic and mass spectrometric analyses. Three new phosphonic acid metabolites, whose structures were confirmed by comparison to chemically synthesized standards, were observed: (2-acetamidoethyl)phosphonic acid (1), (2-acetamido-1-hydroxyethyl)phosphonic (3), and a novel cyanohydrin-containing phosphonate, (cyano(hydroxy)methyl)phosphonic acid (4). The gene cluster responsible for synthesis of these molecules was also identified from the draft genome sequence of S. regensis, laying the groundwork for future investigations into the metabolic pathway leading to this unusual natural product.
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Affiliation(s)
- Joel P. Cioni
- Department of Microbiology and The Institute for Genomic Biology, University of Illinois, Urbana−Champaign, Illinois 61801, United States
| | - James
R. Doroghazi
- Department of Microbiology and The Institute for Genomic Biology, University of Illinois, Urbana−Champaign, Illinois 61801, United States
| | - Kou-San Ju
- Department of Microbiology and The Institute for Genomic Biology, University of Illinois, Urbana−Champaign, Illinois 61801, United States
| | - Xiaomin Yu
- Department of Microbiology and The Institute for Genomic Biology, University of Illinois, Urbana−Champaign, Illinois 61801, United States
| | - Bradley S. Evans
- Department of Microbiology and The Institute for Genomic Biology, University of Illinois, Urbana−Champaign, Illinois 61801, United States
| | - Jaeheon Lee
- Department of Microbiology and The Institute for Genomic Biology, University of Illinois, Urbana−Champaign, Illinois 61801, United States
| | - William W. Metcalf
- Department of Microbiology and The Institute for Genomic Biology, University of Illinois, Urbana−Champaign, Illinois 61801, United States
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24
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Gao J, Ju KS, Yu X, Velásquez JE, Mukherjee S, Lee J, Zhao C, Evans BS, Doroghazi JR, Metcalf WW, van der Donk WA. Use of a phosphonate methyltransferase in the identification of the fosfazinomycin biosynthetic gene cluster. Angew Chem Int Ed Engl 2014; 53:1334-7. [PMID: 24376039 PMCID: PMC3927463 DOI: 10.1002/anie.201308363] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/24/2013] [Revised: 11/16/2013] [Indexed: 12/19/2022]
Abstract
Natural product discovery has been boosted by genome mining approaches, but compound purification is often still challenging. We report an enzymatic strategy for "stable isotope labeling of phosphonates in extract" (SILPE) that facilitates their purification. We used the phosphonate methyltransferase DhpI involved in dehydrophos biosynthesis to methylate a variety of phosphonate natural products in crude spent medium with a mixture of labeled and unlabeled S-adenosyl methionine. Mass-guided fractionation then allowed straightforward purification. We illustrate its utility by purifying a phosphonate that led to the identification of the fosfazinomycin biosynthetic gene cluster. This unusual natural product contains a hydrazide linker between a carboxylic acid and a phosphonic acid. Bioinformatic analysis of the gene cluster provides insights into how such a structure might be assembled.
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Affiliation(s)
- Jiangtao Gao
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West, Gregory Drive, Urbana, Illinois 61801, USA
| | - Kou-San Ju
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West, Gregory Drive, Urbana, Illinois 61801, USA
| | - Xiaomin Yu
- Department of Microbiology, 601 South Goodwin Avenue, Urbana, Illinois 61801, USA
| | - Juan E. Velásquez
- Howard Hughes Medical Institute and Department of Chemistry, University of Illinois at Urbana-Champaign, 600, South Mathews Avenue, Urbana, Illinois 61801, USA
| | - Subha Mukherjee
- Howard Hughes Medical Institute and Department of Chemistry, University of Illinois at Urbana-Champaign, 600, South Mathews Avenue, Urbana, Illinois 61801, USA
| | - Jaeheon Lee
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West, Gregory Drive, Urbana, Illinois 61801, USA
| | - Changming Zhao
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West, Gregory Drive, Urbana, Illinois 61801, USA
| | - Bradley S. Evans
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West, Gregory Drive, Urbana, Illinois 61801, USA
| | - James R. Doroghazi
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West, Gregory Drive, Urbana, Illinois 61801, USA
| | - William W. Metcalf
- Department of Microbiology, 601 South Goodwin Avenue, Urbana, Illinois 61801, USA
| | - Wilfred A. van der Donk
- Howard Hughes Medical Institute and Department of Chemistry, University of Illinois at Urbana-Champaign, 600, South Mathews Avenue, Urbana, Illinois 61801, USA
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25
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Abstract
Cancer cells are characterized by elevated levels of reactive oxygen species, which are produced mainly by the mitochondria. The dismutase SOD2 localizes in the matrix and is a major antioxidant. The activity of SOD2 is regulated by the deacetylase SIRT3. Recent studies indicated that SIRT3 is decreased in 87% of breast cancers, implying that the activity of SOD2 is compromised. The resulting elevation in reactive oxygen species was shown to be essential for the metabolic reprograming toward glycolysis. Here, we show that SOD2 itself is down-regulated in breast cancer cell lines. Further, activation of oncogenes, such as Ras, promotes the rapid down-regulation of SOD2. Because in the absence of SOD2, superoxide levels are elevated in the matrix, we reasoned that mechanisms must exist to retain low levels of superoxide in other cellular compartments especially in the intermembrane space of the mitochondrial to avoid irreversible damage. The dismutase SOD1 also acts as an antioxidant, but it localizes to the cytoplasm and the intermembrane space of the mitochondria. We report here that loss of SOD2 correlates with the overexpression of SOD1. Further, we show that mitochondrial SOD1 is the main dismutase activity in breast cancer cells but not in non-transformed cells. In addition, we show that the SOD1 inhibitor LCS-1 leads to a drastic fragmentation and swelling of the matrix, suggesting that in the absence of SOD2, SOD1 is required to maintain the integrity of the organelle. We propose that by analogy to the cadherin switch during epithelial-mesenchymal transition, cancer cells also undergo a SOD switch during transformation.
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Affiliation(s)
- Luena Papa
- From the the Department of Medicine, Division of Hematology/Oncology, Tisch Cancer Institute, Mount Sinai School of Medicine, New York, New York 10029 and
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26
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Gao J, Ju KS, Yu X, Velásquez JE, Mukherjee S, Lee J, Zhao C, Evans BS, Doroghazi JR, Metcalf WW, van der Donk WA. Use of a Phosphonate Methyltransferase in the Identification of the Fosfazinomycin Biosynthetic Gene Cluster. Angew Chem Int Ed Engl 2013. [DOI: 10.1002/ange.201308363] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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27
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Evans BS, Zhao C, Gao J, Evans CM, Ju KS, Doroghazi JR, van der Donk WA, Kelleher NL, Metcalf WW. Discovery of the antibiotic phosacetamycin via a new mass spectrometry-based method for phosphonic acid detection. ACS Chem Biol 2013; 8:908-13. [PMID: 23474169 DOI: 10.1021/cb400102t] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Naturally occurring phosphonates such as phosphinothricin (Glufosinate, a commercially used herbicide) and fosfomycin (Monurol, a clinically used antibiotic) have proved to be potent and useful biocides. Yet this class of natural products is still an under explored family of secondary metabolites. Discovery of the biosynthetic pathways responsible for the production of these compounds has been simplified by using gene based screening approaches, but detection and identification of the natural products the genes produce have been hampered by a lack of high-throughput methods for screening potential producers under various culture conditions. Here, we present an efficient mass-spectrometric method for the selective detection of natural products containing phosphonate and phosphinate functional groups. We have used this method to identify a new phosphonate metabolite, phosacetamycin, whose structure, biological activity, and biosynthetic gene cluster are reported.
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Affiliation(s)
| | | | | | | | | | | | | | - Neil L. Kelleher
- Northwestern University, Evanston, Illinois 60208, United States
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28
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Warlick BP, Evans BS, Erb TJ, Ramagopal UA, Sriram J, Imker HJ, Sauder JM, Bonanno JB, Burley SK, Tabita FR, Almo SC, Sweedler JS, Gerlt JA. 1-methylthio-D-xylulose 5-phosphate methylsulfurylase: a novel route to 1-deoxy-D-xylulose 5-phosphate in Rhodospirillum rubrum. Biochemistry 2012; 51:8324-6. [PMID: 23035785 DOI: 10.1021/bi301215g] [Citation(s) in RCA: 14] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
Rhodospirillum rubrum produces 5-methylthioadenosine (MTA) from S-adenosylmethionine in polyamine biosynthesis; however, R. rubrum lacks the classical methionine salvage pathway. Instead, MTA is converted to 5-methylthio-d-ribose 1-phosphate (MTR 1-P) and adenine; MTR 1-P is isomerized to 1-methylthio-d-xylulose 5-phosphate (MTXu 5-P) and reductively dethiomethylated to 1-deoxy-d-xylulose 5-phosphate (DXP), an intermediate in the nonmevalonate isoprenoid pathway [Erb, T. J., et al. (2012) Nat. Chem. Biol., in press]. Dethiomethylation, a novel route to DXP, is catalyzed by MTXu 5-P methylsulfurylase. An active site Cys displaces the enolate of DXP from MTXu 5-P, generating a methyl disulfide intermediate.
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Affiliation(s)
- Benjamin P Warlick
- Department of Biochemistry, University of Illinois at Urbana-Champaign, Urbana, IL 61801, USA
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29
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Metcalf WW, Griffin BM, Cicchillo RM, Gao J, Janga SC, Cooke HA, Circello BT, Evans BS, Martens-Habbena W, Stahl DA, van der Donk WA. Synthesis of methylphosphonic acid by marine microbes: a source for methane in the aerobic ocean. Science 2012; 337:1104-7. [PMID: 22936780 DOI: 10.1126/science.1219875] [Citation(s) in RCA: 149] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Relative to the atmosphere, much of the aerobic ocean is supersaturated with methane; however, the source of this important greenhouse gas remains enigmatic. Catabolism of methylphosphonic acid by phosphorus-starved marine microbes, with concomitant release of methane, has been suggested to explain this phenomenon, yet methylphosphonate is not a known natural product, nor has it been detected in natural systems. Further, its synthesis from known natural products would require unknown biochemistry. Here we show that the marine archaeon Nitrosopumilus maritimus encodes a pathway for methylphosphonate biosynthesis and that it produces cell-associated methylphosphonate esters. The abundance of a key gene in this pathway in metagenomic data sets suggests that methylphosphonate biosynthesis is relatively common in marine microbes, providing a plausible explanation for the methane paradox.
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Affiliation(s)
- William W Metcalf
- Institute for Genomic Biology, University of Illinois, Urbana, IL 61801, USA.
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30
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Abstract
![]()
Methylphosphonate synthase is a non-heme iron-dependent
oxygenase
that converts 2-hydroxyethylphosphonate (2-HEP) to methylphosphonate.
On the basis of experiments with two enantiomers of a substrate analog,
2-hydroxypropylphosphonate, catalysis is proposed to commence with
stereospecific abstraction of the pro-S hydrogen
on C2 of the substrate. Experiments with isotopologues of 2-HEP indicate
stereospecific hydrogen transfer of the pro-R hydrogen
at C2 of the substrate to the methyl group of methylphosphonate. Kinetic
studies with these substrate isotopologues reveal that neither hydrogen
transfer is rate limiting under saturating substrate conditions. A
mechanism is proposed that is consistent with the available data.
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Affiliation(s)
- Heather A Cooke
- Howard Hughes Medical Institute and Department of Chemistry, University of Illinois at Urbana-Champaign, 600 South Mathews Avenue, Urbana, Illinois 61801, United States
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31
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Molohon KJ, Melby JO, Lee J, Evans BS, Dunbar KL, Bumpus SB, Kelleher NL, Mitchell DA. Characterizing the plantazolicins: structure and discriminating activity of a novel class of natural products. FASEB J 2012. [DOI: 10.1096/fasebj.26.1_supplement.552.1] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/11/2022]
Affiliation(s)
| | - Joel O Melby
- ChemistryUniversity of Illinois Urbana-ChampaignUrbanaIL
| | - Jaeheon Lee
- Institute for Genomic BiologyUniversity of Illinois Urbana-ChampaignUrbanaIL
| | - Bradley S Evans
- Institute for Genomic BiologyUniversity of Illinois Urbana-ChampaignUrbanaIL
| | - Kyle L Dunbar
- ChemistryUniversity of Illinois Urbana-ChampaignUrbanaIL
| | | | - Neil L Kelleher
- Chemistry and Chemistry of Life Processes InstituteNorwestern UniversityEvanstonIL
| | - Douglas A Mitchell
- MicrobiologyUniversity of Illinois Urbana-ChampaignUrbanaIL
- ChemistryUniversity of Illinois Urbana-ChampaignUrbanaIL
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32
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Peck SC, Kim SY, Evans BS, van der Donk WA. Stereochemistry of Hydride Transfer by Group III Alcohol Dehydrogenases Involved in Phosphonate Biosynthesis. Medchemcomm 2012; 3:967-970. [PMID: 25400901 DOI: 10.1039/c2md20009k] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Affiliation(s)
- Spencer C Peck
- Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA. ; Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL, 61801, USA
| | - Seung Young Kim
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL, 61801, USA
| | - Bradley S Evans
- Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL, 61801, USA
| | - Wilfred A van der Donk
- Department of Chemistry and Howard Hughes Medical Institute, University of Illinois at Urbana-Champaign, 600 S. Mathews Ave., Urbana, IL, 61801, USA. ; Institute for Genomic Biology, University of Illinois at Urbana-Champaign, 1206 West Gregory Drive, Urbana, IL, 61801, USA
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33
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Molohon KJ, Melby JO, Lee J, Evans BS, Dunbar KL, Bumpus SB, Kelleher NL, Mitchell DA. Structure determination and interception of biosynthetic intermediates for the plantazolicin class of highly discriminating antibiotics. ACS Chem Biol 2011; 6:1307-13. [PMID: 21950656 DOI: 10.1021/cb200339d] [Citation(s) in RCA: 69] [Impact Index Per Article: 5.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
The soil-dwelling, plant growth-promoting bacterium Bacillus amyloliquefaciens FZB42 is a prolific producer of complex natural products. Recently, a new FZB42 metabolite, plantazolicin (PZN), has been described as a member of the growing thiazole/oxazole-modified microcin (TOMM) family. TOMMs are biosynthesized from inactive, ribosomal peptides and undergo a series of cyclodehydrations, dehydrogenations, and other modifications to become bioactive natural products. Using high-resolution mass spectrometry, chemoselective modification, genetic interruptions, and other spectroscopic tools, we have determined the molecular structure of PZN. In addition to two conjugated polyazole moieties, the amino-terminus of PZN has been modified to N(α),N(α)-dimethylarginine. PZN exhibited a highly selective antibiotic activity toward Bacillus anthracis, but no other tested human pathogen. By altering oxygenation levels during fermentation, PZN analogues were produced that bear variability in their heterocycle content, which yielded insight into the order of biosynthetic events. Lastly, genome-mining has revealed the existence of four additional PZN-like biosynthetic gene clusters. Given their structural uniqueness and intriguing antimicrobial specificity, the PZN class of antibiotics may hold pharmacological value.
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Affiliation(s)
| | | | | | | | | | | | - Neil L. Kelleher
- Department of Chemistry and Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
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34
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Ames BD, Haynes SW, Gao X, Evans BS, Kelleher NL, Tang Y, Walsh CT. Complexity generation in fungal peptidyl alkaloid biosynthesis: oxidation of fumiquinazoline A to the heptacyclic hemiaminal fumiquinazoline C by the flavoenzyme Af12070 from Aspergillus fumigatus. Biochemistry 2011; 50:8756-69. [PMID: 21899262 DOI: 10.1021/bi201302w] [Citation(s) in RCA: 48] [Impact Index Per Article: 3.7] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The human pathogen Aspergillus fumigatus makes a series of fumiquinazoline (FQ) peptidyl alkaloids of increasing scaffold complexity using L-Trp, 2 equiv of L-Ala, and the non-proteinogenic amino acid anthranilate as building blocks. The FQ gene cluster encodes two non-ribosomal peptide synthetases (NRPS) and two flavoproteins. The trimodular NRPS Af12080 assembles FQF (the first level of complexity) while the next two enzymes, Af12060 and Af12050, act in tandem in an oxidative annulation sequence to couple alanine to the indole side chain of FQF to yield the imidazolindolone-containing FQA. In this study we show that the fourth enzyme, the monocovalent flavoprotein Af12070, introduces a third layer of scaffold complexity by converting FQA to the spirohemiaminal FQC, presumably by catalyzing the formation of a transient imine within the pyrazinone ring (and therefore acting in an unprecedented manner as an FAD-dependent amide oxidase). FQC subsequently converts nonenzymatically to the known cyclic aminal FQD. We also investigated the effect of substrate structure on Af12070 activity and subsequent cyclization with a variety of FQA analogues, including an FQA diastereomer (2'-epi-FQA), which is an intermediate in the fungal biosynthesis of the tremorgenic tryptoquialanine. 2'-epi-FQA is processed by Af12070 to epi-FQD, not epi-FQC, illustrating that the delicate balance in product cyclization regiochemistry can be perturbed by a remote stereochemical center.
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Affiliation(s)
- Brian D Ames
- Department of Biological Chemistry & Molecular Pharmacology, Harvard Medical School, Boston, Massachusetts 02115, United States
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35
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Evans BS, Chen Y, Metcalf WW, Zhao H, Kelleher NL. Directed evolution of the nonribosomal peptide synthetase AdmK generates new andrimid derivatives in vivo. Chem Biol 2011; 18:601-7. [PMID: 21609841 PMCID: PMC3102229 DOI: 10.1016/j.chembiol.2011.03.008] [Citation(s) in RCA: 96] [Impact Index Per Article: 7.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/20/2010] [Revised: 02/02/2011] [Accepted: 03/07/2011] [Indexed: 11/17/2022]
Abstract
Many lead compounds in the search for new drugs derive from peptides and polyketides whose similar biosynthetic enzymes have been difficult to engineer for production of new derivatives. Problems with generating multiple analogs in a single experiment along with lack of high-throughput methods for structure-based screening have slowed progress in this area. Here, we use directed evolution and a multiplexed assay to screen a library of >14,000 members to generate three derivatives of the antibacterial compound, andrimid. Another limiting factor in reengineering these mega-enzymes of secondary metabolism has been that commonly used hosts such as Escherichia coli often give lower product titers, so our reengineering was performed in the native producer, Pantoea agglomerans. This integrated in vivo approach can be extended to larger enzymes to create analogs of natural products for bioactivity testing.
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Affiliation(s)
- Bradley S. Evans
- Department of Biochemistry, University of Illinois, Urbana, IL 61801
- Institute for Genomic Biology, University of Illinois, Urbana, IL 61801
| | - Yunqiu Chen
- Department of Chemistry, Northwestern University, Evanston, IL 60208
- The Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208
| | - William W. Metcalf
- Institute for Genomic Biology, University of Illinois, Urbana, IL 61801
- Department of Microbiology, University of Illinois, Urbana, IL 61801
| | - Huimin Zhao
- Institute for Genomic Biology, University of Illinois, Urbana, IL 61801
- Department of Chemical and Biomolecular Engineering, University of Illinois, Urbana, IL 61801
| | - Neil L. Kelleher
- Department of Chemistry, Northwestern University, Evanston, IL 60208
- Department of Molecular Biosciences, Northwestern University, Evanston, IL 60208
- The Chemistry of Life Processes Institute, Northwestern University, Evanston, IL 60208
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36
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Abstract
Nonribosomal peptide synthetases (NRPSs) and polyketide synthases (PKSs) are large enzymes responsible for the biosynthesis of medically and ecologically important secondary metabolites. In a previous report, we described a proteomics approach to screen for expressed NRPSs or PKSs from bacteria with or without sequenced genomes. Here we used this proteome mining approach to discover a novel natural product arising from rare adenylation (A) and reductase (Red) domains in its biosynthetic machinery. We also cloned the entire gene cluster and elucidated the biosynthesis of the new compound, which is produced by an unsequenced Bacillus sp. isolated from soil collected in Koran, Louisiana.
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Affiliation(s)
- Bradley S Evans
- Institute of Genomic Biology, University of Illinois Urbana-Champaign, 1206 West Gregory Drive, Urbana, Illinois 61801, USA
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Lee JH, Evans BS, Li G, Kelleher NL, van der Donk WA. In vitro characterization of a heterologously expressed nonribosomal Peptide synthetase involved in phosphinothricin tripeptide biosynthesis. Biochemistry 2009; 48:5054-6. [PMID: 19432442 PMCID: PMC2709985 DOI: 10.1021/bi900164d] [Citation(s) in RCA: 17] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
The late stages of biosynthesis of phosphinothricin tripeptide (PTT) involve peptide formation and methylation on phosphorus. The exact timing of these transformations is not known. To provide insight into this question, we developed a heterologous expression system for PhsA, one of three NRPS proteins in PTT biosynthesis. The apparent k(cat)/K(m) value for ATP-pyrophosphate exchange activity for d,l-N-acetylphosphinothricin was 3.5 muM(-1) min(-1), whereas the k(cat)/K(m,app) for l-N-acetyldemethylphosphinothricin was 0.5 microM(-1) min(-1), suggesting the former might be the physiological substrate. Each substrate could be loaded onto the phosphopantetheine arm of the thiolation domain as observed by Fourier transform mass spectrometry (FTMS).
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Affiliation(s)
- Jin-Hee Lee
- Department of Chemistry, University of Illinois, Urbana,Illinois 61801, USA
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Abstract
If you look at the biggest genes in soil and marine bacteria, you tend to see the chemical blueprints for making natural products such as peptides and polyketides. Over the past decade, collective efforts of enzymologists working with synthetic and analytical chemists have been catching up with the data dump from microbial genome sequencing. Following this story line, we now understand how cyanobacteria construct scaffolds for the related natural products curacin and jamaicamide using subtle tweaks to non-standard biosynthetic machinery.
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Affiliation(s)
- Bradley S. Evans
- Department of Biochemistry
- The Institute of Genomic Biology, University of Illinois Urbana−Champaign, Urbana, Illinois 61802
| | - Neil L. Kelleher
- Department of Biochemistry
- Department of Chemistry
- The Institute of Genomic Biology, University of Illinois Urbana−Champaign, Urbana, Illinois 61802
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Evans BS. Integrating technology with compassionate care: withdrawal of ventilation in a conscious patient with apnea. Am J Crit Care 1998; 7:328. [PMID: 9656049] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/08/2023]
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Evans BS. Integrating technology with compassionate care: withdrawal of ventilation in a conscious patient with apnea. Am J Crit Care 1998. [DOI: 10.4037/ajcc1998.7.4.328-a] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/01/2022]
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Klasson KT, Barton JW, Evans BS, Reeves ME. Reductive microbial dechlorination of indigenous polychlorinated biphenyls in soil using a sediment-free inoculum. Biotechnol Prog 1996; 12:310-5. [PMID: 8652118 DOI: 10.1021/bp960019z] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
In laboratory experiments, unagitated soil slurry bioreactors inoculated with micro-organisms extracted from polychlorinated biphenyl-contaminated (PCBs) sediments from the Hudson River were used to anaerobically dechlorinate PCBs. The onset of dechlorination activity was accelerated by the addition of certain organic acids (pyruvate and maleate) and single congeners (2,3,6-trichlorobiphenyl). Dechlorination was observed under several working conditions after 19 weeks of incubation with PCB-contaminated soil and nutrient solution. Best results showed a drop in average chlorine content from 4.3 to 3.6 chlorines per biphenyl due to a loss of m-chlorines. Soil used for these experiments was obtained from a PCB-contaminated (weathered Aroclor 1248) site at an electric power substation. Dechlorination was observed with no sediment particles or other matrix being added.
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Affiliation(s)
- K T Klasson
- Chemical Technology Division, Oak Ridge National Laboratory, Tennessee 37831-6044, USA
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Abstract
Many industrial locations have identified the need for treatment of polychlorinated biphenyl (PCB) wastes and remediation of PCB-contaminated sites. Biodegradation of PCBs is a potentially effective technology for treatment of PCB-contaminated soils and sludges; however, a practicable remediation technology has not yet been demonstrated. In laboratory experiments, soil slurry microcosms inoculated with microorganisms extracted from PCB-contaminated Hudson River sediments have been used for anaerobic dechlorination of weathered Aroclor 1248 in contaminated soil with a low organic carbon content. Anaerobic incubation was then followed by exposure to air, addition of biphenyl, and inoculation with Pseudomonas sp. LB400, an aerobic PCB degrader. The sequential anaerobic-aerobic treatment constituted an improvement compared to anaerobic or aerobic treatment alone by reducing the total amount of PCBs remaining and decreasing the tendency for end products to accumulate in humans. A 70% reduction of PCBs was observed during sequential treatment with products containing fewer chlorines and having a shorter half-life in humans than the original PCBs. The aerobic treatment alone was also quite effective as a stand-alone treatment reducing the PCBs by 67%. The results represent a case in which anaerobic river sediment organisms have been successfully transferred to a matrix free of river or lake sediments.
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Affiliation(s)
- B S Evans
- Chemical Technology Division, Oak Ridge National Laboratory, TN 37831-6044, USA
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Ary KR, White PC, Evans BS. Podiatric services in a public health department hypertension clinic. J Am Podiatr Med Assoc 1985; 75:111-2. [PMID: 3981439 DOI: 10.7547/87507315-75-2-111] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [MESH Headings] [Track Full Text] [Journal Information] [Submit a Manuscript] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
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