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Sutter M, Utschig LM, Niklas J, Paul S, Kahan DN, Gupta S, Poluektov OG, Ferlez BH, Tefft NM, TerAvest MA, Hickey DP, Vermaas JV, Ralston CY, Kerfeld CA. Electrochemical cofactor recycling of bacterial microcompartments. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.07.15.603600. [PMID: 39071365 PMCID: PMC11275729 DOI: 10.1101/2024.07.15.603600] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 07/30/2024]
Abstract
Bacterial microcompartments (BMCs) are prokaryotic organelles that consist of a protein shell which sequesters metabolic reactions in its interior. While most of the substrates and products are relatively small and can permeate the shell, many of the encapsulated enzymes require cofactors that must be regenerated inside. We have analyzed the occurrence of an enzyme previously assigned as a cobalamin (vitamin B12) reductase and, curiously, found it in many unrelated BMC types that do not employ B12 cofactors. We propose NAD+ regeneration as a new function of this enzyme and name it MNdh, for Metabolosome NADH dehydrogenase. Its partner shell protein BMC-TSE assists in passing the generated electrons to the outside. We support this hypothesis with bioinformatic analysis, functional assays, EPR spectroscopy, protein voltammetry and structural modeling verified with X-ray footprinting. This discovery represents a new paradigm for the BMC field, identifying a new, widely occurring route for cofactor recycling and a new function for the shell as separating redox environments.
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Affiliation(s)
- Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University; East Lansing, MI 48824, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory; Berkeley, CA 94720, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory; Berkeley, CA 94720, USA
| | - Lisa M. Utschig
- Chemical Sciences and Engineering Division, Argonne National Laboratory; Lemont, IL 60439, USA
| | - Jens Niklas
- Chemical Sciences and Engineering Division, Argonne National Laboratory; Lemont, IL 60439, USA
| | - Sathi Paul
- Molecular Foundry Division, Lawrence Berkeley National Laboratory; Berkeley, CA 94720, USA
| | - Darren N. Kahan
- Biophysics Graduate Program, University of California; Berkeley, CA, 94720, USA
| | - Sayan Gupta
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory; Berkeley, CA 94720, USA
| | - Oleg G. Poluektov
- Chemical Sciences and Engineering Division, Argonne National Laboratory; Lemont, IL 60439, USA
| | - Bryan H. Ferlez
- MSU-DOE Plant Research Laboratory, Michigan State University; East Lansing, MI 48824, USA
| | - Nicholas M. Tefft
- Department of Biochemistry and Molecular Biology, Michigan State University; East Lansing, MI 48824, USA
| | - Michaela A. TerAvest
- Department of Biochemistry and Molecular Biology, Michigan State University; East Lansing, MI 48824, USA
| | - David P. Hickey
- Department of Chemical Engineering and Materials Science, Michigan State University; East Lansing, MI 48824, USA
| | - Josh V. Vermaas
- MSU-DOE Plant Research Laboratory, Michigan State University; East Lansing, MI 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University; East Lansing, MI 48824, USA
| | - Corie Y. Ralston
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory; Berkeley, CA 94720, USA
- Molecular Foundry Division, Lawrence Berkeley National Laboratory; Berkeley, CA 94720, USA
| | - Cheryl A. Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University; East Lansing, MI 48824, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory; Berkeley, CA 94720, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory; Berkeley, CA 94720, USA
- Department of Biochemistry and Molecular Biology, Michigan State University; East Lansing, MI 48824, USA
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2
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Gu S, Bradley-Clarke J, Rose RS, Warren MJ, Pickersgill RW. Enzyme-cargo encapsulation peptides bind between tessellating tiles of the bacterial microcompartment shell. J Biol Chem 2024; 300:107357. [PMID: 38735476 PMCID: PMC11157265 DOI: 10.1016/j.jbc.2024.107357] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/24/2023] [Revised: 04/11/2024] [Accepted: 04/14/2024] [Indexed: 05/14/2024] Open
Abstract
Bacterial microcompartments are prokaryotic organelles comprising encapsulated enzymes within a thin protein shell. They facilitate metabolic processing including propanediol, choline, glycerol, and ethanolamine utilization, and they accelerate carbon fixation in cyanobacteria. Enzymes targeted to the inside of the microcompartment frequently possess a cargo-encapsulation peptide, but the site to which the peptide binds is unclear. We provide evidence that the encapsulation peptides bind to the hydrophobic groove formed between tessellating subunits of the shell proteins. In silico docking studies provide a compelling model of peptide binding to this prominent hydrophobic groove. This result is consistent with the now widely accepted view that the convex side of the shell oligomers faces the lumen of the microcompartment. The binding of the encapsulation peptide to the groove between tessellating shell protein tiles explains why it has been difficult to define the peptide binding site using other methods, provides a mechanism by which encapsulation-peptide bearing enzymes can promote shell assembly, and explains how the presence of cargo affects the size and shape of the bacterial microcompartment. This knowledge may be exploited in engineering microcompartments or disease prevention by hampering cargo encapsulation.
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Affiliation(s)
- Shuang Gu
- School of Biological and Behavioral Sciences, Queen Mary University of London, London, UK
| | - Jack Bradley-Clarke
- School of Biological and Behavioral Sciences, Queen Mary University of London, London, UK
| | - Ruth-Sarah Rose
- School of Biological and Behavioral Sciences, Queen Mary University of London, London, UK
| | - Martin J Warren
- School of Biosciences, University of Kent, Canterbury, Kent, UK
| | - Richard W Pickersgill
- School of Biological and Behavioral Sciences, Queen Mary University of London, London, UK.
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3
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Doron L, Sutter M, Kerfeld CA. Characterization of a novel aromatic substrate-processing microcompartment in Actinobacteria. mBio 2023; 14:e0121623. [PMID: 37462359 PMCID: PMC10470539 DOI: 10.1128/mbio.01216-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/02/2023] [Accepted: 06/07/2023] [Indexed: 09/02/2023] Open
Abstract
We have discovered a new cluster of genes that is found exclusively in the Actinobacteria phylum. This locus includes genes for the 2-aminophenol meta-cleavage pathway and the shell proteins of a bacterial microcompartment (BMC) and has been named aromatics (ARO) for its putative role in the breakdown of aromatic compounds. In this study, we provide details about the distribution and composition of the ARO BMC locus and conduct phylogenetic, structural, and functional analyses of the first two enzymes in the catabolic pathway: a unique 2-aminophenol dioxygenase, which is exclusively found alongside BMC shell genes in Actinobacteria, and a semialdehyde dehydrogenase, which works downstream of the dioxygenase. Genomic analysis reveals variations in the complexity of the ARO loci across different orders. Some loci are simple, containing shell proteins and enzymes for the initial steps of the catabolic pathway, while others are extensive, encompassing all the necessary genes for the complete breakdown of 2-aminophenol into pyruvate and acetyl-CoA. Furthermore, our analysis uncovers two subtypes of ARO BMC that likely degrade either 2-aminophenol or catechol, depending on the presence of a pathway-specific gene within the ARO locus. The precise precursor of 2-aminophenol, which serves as the initial substrate and/or inducer for the ARO pathway, remains unknown, as our model organism Micromonospora rosaria cannot utilize 2-aminophenol as its sole energy source. However, using enzymatic assays, we demonstrate the dioxygenase's ability to cleave both 2-aminophenol and catechol in vitro, in collaboration with the aldehyde dehydrogenase, to facilitate the rapid conversion of these unstable and toxic intermediates. IMPORTANCE Bacterial microcompartments (BMCs) are proteinaceous organelles that are widespread among bacteria and provide a competitive advantage in specific environmental niches. Studies have shown that the genetic information necessary to form functional BMCs is encoded in loci that contain genes encoding shell proteins and the enzymatic core. This allows the bioinformatic discovery of BMCs with novel functions and expands our understanding of the metabolic diversity of BMCs. ARO loci, found only in Actinobacteria, contain genes encoding for phylogenetically remote shell proteins and homologs of the meta-cleavage degradation pathway enzymes that were shown to convert central aromatic intermediates into pyruvate and acetyl-CoA in gamma Proteobacteria. By analyzing the gene composition of ARO BMC loci and characterizing two core enzymes phylogenetically, structurally, and functionally, we provide an initial functional characterization of the ARO BMC, the most unusual BMC identified to date, distinctive among the repertoire of studied BMCs.
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Affiliation(s)
- Lior Doron
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Cheryl A. Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Environmental Genomics and Systems Biology Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Molecular Biophysics and Integrative Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, California, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
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4
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Yang M, Wenner N, Dykes GF, Li Y, Zhu X, Sun Y, Huang F, Hinton JCD, Liu LN. Biogenesis of a bacterial metabolosome for propanediol utilization. Nat Commun 2022; 13:2920. [PMID: 35614058 PMCID: PMC9132943 DOI: 10.1038/s41467-022-30608-w] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/28/2021] [Accepted: 04/22/2022] [Indexed: 12/24/2022] Open
Abstract
Bacterial metabolosomes are a family of protein organelles in bacteria. Elucidating how thousands of proteins self-assemble to form functional metabolosomes is essential for understanding their significance in cellular metabolism and pathogenesis. Here we investigate the de novo biogenesis of propanediol-utilization (Pdu) metabolosomes and characterize the roles of the key constituents in generation and intracellular positioning of functional metabolosomes. Our results demonstrate that the Pdu metabolosome undertakes both "Shell first" and "Cargo first" assembly pathways, unlike the β-carboxysome structural analog which only involves the "Cargo first" strategy. Shell and cargo assemblies occur independently at the cell poles. The internal cargo core is formed through the ordered assembly of multiple enzyme complexes, and exhibits liquid-like properties within the metabolosome architecture. Our findings provide mechanistic insight into the molecular principles driving bacterial metabolosome assembly and expand our understanding of liquid-like organelle biogenesis.
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Affiliation(s)
- Mengru Yang
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Nicolas Wenner
- Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Gregory F Dykes
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Yan Li
- Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Xiaojun Zhu
- Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Yaqi Sun
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Fang Huang
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Jay C D Hinton
- Institute of Infection, Veterinary & Ecological Sciences, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom
| | - Lu-Ning Liu
- Institute of Systems, Molecular and Integrative Biology, University of Liverpool, Crown Street, Liverpool, L69 7ZB, United Kingdom.
- College of Marine Life Sciences, and Frontiers Science Center for Deep Ocean Multispheres and Earth System, Ocean University of China, Qingdao, 266003, China.
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5
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Edwardson TGW, Levasseur MD, Tetter S, Steinauer A, Hori M, Hilvert D. Protein Cages: From Fundamentals to Advanced Applications. Chem Rev 2022; 122:9145-9197. [PMID: 35394752 DOI: 10.1021/acs.chemrev.1c00877] [Citation(s) in RCA: 41] [Impact Index Per Article: 20.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
Proteins that self-assemble into polyhedral shell-like structures are useful molecular containers both in nature and in the laboratory. Here we review efforts to repurpose diverse protein cages, including viral capsids, ferritins, bacterial microcompartments, and designed capsules, as vaccines, drug delivery vehicles, targeted imaging agents, nanoreactors, templates for controlled materials synthesis, building blocks for higher-order architectures, and more. A deep understanding of the principles underlying the construction, function, and evolution of natural systems has been key to tailoring selective cargo encapsulation and interactions with both biological systems and synthetic materials through protein engineering and directed evolution. The ability to adapt and design increasingly sophisticated capsid structures and functions stands to benefit the fields of catalysis, materials science, and medicine.
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Affiliation(s)
| | | | - Stephan Tetter
- Laboratory of Organic Chemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Angela Steinauer
- Laboratory of Organic Chemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Mao Hori
- Laboratory of Organic Chemistry, ETH Zurich, 8093 Zurich, Switzerland
| | - Donald Hilvert
- Laboratory of Organic Chemistry, ETH Zurich, 8093 Zurich, Switzerland
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6
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Kumar G, Bari NK, Hazra JP, Sinha S. A major shell protein of 1,2-propanediol utilization microcompartment conserves the activity of its signature enzyme at higher temperatures. Chembiochem 2022; 23:e202100694. [PMID: 35229962 DOI: 10.1002/cbic.202100694] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/20/2021] [Revised: 02/28/2022] [Indexed: 11/11/2022]
Abstract
A classic example of an all-protein natural nano-bioreactor, the bacterial microcompartment is a special kind of prokaryotic organelle that confine enzymes within a small volume enveloped by an outer protein shell. These protein compartments metabolize specific organic molecules, allowing bacteria to survive in restricted nutrient environments. In this work, 1,2-propanediol utilization microcompartment (PduMCP) is used as a model to study the effect of molecular confinement on the stability and catalytic activity of native enzymes in microcompartment. A combination of enzyme assays, spectroscopic techniques, binding assays, and computational analysis are used to evaluate the impact of the major shell protein PduBB' on the stability and activity of PduMCP's signature enzyme, diol dehydratase PduCDE. While free PduCDE shows ~45% reduction in its optimum activity (activity at 37 o C) when exposed to a temperature of 45°C, it retains similar activity up to 50°C when encapsulated within PduMCP. PduBB', a major component of the outer shell of PduMCP, preserves the catalytic efficiency of PduCDE under thermal stress and prevents temperature-induced unfolding and aggregation of PduCDE in vitro . We observe that while both PduB and PduB' interact with the enzyme with micromolar affinity, only the PduBB' combination influences its activity and stability, highlighting the importance of the unique PduBB' combination in the functioning of PduMCP.
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Affiliation(s)
- Gaurav Kumar
- Institute of Nano Science and Technology, Chemical Biology Unit, Sector-81, Knowledge City, 140306, Mohali, INDIA
| | - Naimat Kalim Bari
- Institute of Nano Science and Technology, Chemical Biology Unit, Sector-81, Knowledge City, 140306, Mohali, INDIA
| | - Jagadish P Hazra
- Indian Institute of Science Education and Research Mohali, Chemical Sciences, Sector-81, Knowledge City, 140306, Mohali, INDIA
| | - Sharmistha Sinha
- Institute of Nano Science and Technology, Chemical Biology Unit, Sector-81, Knowledge City, 140306, Mohali, INDIA
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7
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Toward a glycyl radical enzyme containing synthetic bacterial microcompartment to produce pyruvate from formate and acetate. Proc Natl Acad Sci U S A 2022; 119:2116871119. [PMID: 35193962 PMCID: PMC8872734 DOI: 10.1073/pnas.2116871119] [Citation(s) in RCA: 22] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 01/05/2022] [Indexed: 12/15/2022] Open
Abstract
The enormous complexity of metabolic pathways, in both their regulation and propensity for metabolite cross-talk, represents a major obstacle for metabolic engineering. Self-assembling, catalytically programmable and genetically transferable bacterial microcompartments (BMCs) offer solutions to decrease this complexity through compartmentalization of enzymes within a selectively permeable protein shell. Synthetic BMCs can operate as autonomous metabolic modules decoupled from the cell’s regulatory network, only interfacing with the cell’s metabolism via the highly engineerable proteinaceous shell. Here, we build a synthetic, modular, multienzyme BMC. It functions not only as a proof-of-concept for next-generation metabolic engineering, but also provides the foundation for subsequent tuning, with the goal to create a microanaerobic environment protecting an oxygen-sensitive reaction in aerobic growth conditions that could be deployed. Formate has great potential to function as a feedstock for biorefineries because it can be sustainably produced by a variety of processes that don’t compete with agricultural production. However, naturally formatotrophic organisms are unsuitable for large-scale cultivation, difficult to engineer, or have inefficient native formate assimilation pathways. Thus, metabolic engineering needs to be developed for model industrial organisms to enable efficient formatotrophic growth. Here, we build a prototype synthetic formate utilizing bacterial microcompartment (sFUT) encapsulating the oxygen-sensitive glycyl radical enzyme pyruvate formate lyase and a phosphate acyltransferase to convert formate and acetyl-phosphate into the central biosynthetic intermediate pyruvate. This metabolic module offers a defined environment with a private cofactor coenzyme A that can cycle efficiently between the encapsulated enzymes. To facilitate initial design-build-test-refine cycles to construct an active metabolic core, we used a “wiffleball” architecture, defined as an icosahedral bacterial microcompartment (BMC) shell with unoccupied pentameric vertices to freely permit substrate and product exchange. The resulting sFUT prototype wiffleball is an active multi enzyme synthetic BMC functioning as platform technology.
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8
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Trettel DS, Resager W, Ueberheide BM, Jenkins CC, Winkler WC. Chemical probing provides insight into the native assembly state of a bacterial microcompartment. Structure 2022; 30:537-550.e5. [PMID: 35216657 PMCID: PMC8995372 DOI: 10.1016/j.str.2022.02.002] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Revised: 12/08/2021] [Accepted: 01/28/2022] [Indexed: 11/28/2022]
Abstract
Bacterial microcompartments (BMCs) are widespread in bacteria and are used for a variety of metabolic purposes, including catabolism of host metabolites. A suite of proteins self-assembles into the shell and cargo layers of BMCs. However, the native assembly state of these large complexes remains to be elucidated. Herein, chemical probes were used to observe structural features of a native BMC. While the exterior could be demarcated with fluorophores, the interior was unexpectedly permeable, suggesting that the shell layer may be more dynamic than previously thought. This allowed access to cross-linking chemical probes, which were analyzed to uncover the protein interactome. These cross-links revealed a complex multivalent network among cargo proteins that contained encapsulation peptides and demonstrated that the shell layer follows discrete rules in its assembly. These results are consistent overall with a model in which biomolecular condensation drives interactions of cargo proteins before envelopment by shell layer proteins.
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Affiliation(s)
- Daniel S Trettel
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - William Resager
- New York University Grossman School of Health, NYU Langone Health, New York, NY 10016, USA
| | - Beatrix M Ueberheide
- New York University Grossman School of Health, NYU Langone Health, New York, NY 10016, USA; Department of Biochemistry and Molecular Pharmacology, New York University Grossman School of Medicine, New York, NY 10016, USA; Department of Neurology, New York University Grossman School of Medicine, New York, NY 10016, USA
| | - Conor C Jenkins
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA
| | - Wade C Winkler
- Department of Chemistry and Biochemistry, University of Maryland, College Park, MD 20742, USA; Department of Cell Biology and Molecular Genetics, University of Maryland, College Park, MD 20742, USA.
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9
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Yagi S, Padhi AK, Vucinic J, Barbe S, Schiex T, Nakagawa R, Simoncini D, Zhang KYJ, Tagami S. Seven Amino Acid Types Suffice to Create the Core Fold of RNA Polymerase. J Am Chem Soc 2021; 143:15998-16006. [PMID: 34559526 DOI: 10.1021/jacs.1c05367] [Citation(s) in RCA: 5] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/16/2022]
Abstract
The extant complex proteins must have evolved from ancient short and simple ancestors. The double-ψ β-barrel (DPBB) is one of the oldest protein folds and conserved in various fundamental enzymes, such as the core domain of RNA polymerase. Here, by reverse engineering a modern DPBB domain, we reconstructed its plausible evolutionary pathway started by "interlacing homodimerization" of a half-size peptide, followed by gene duplication and fusion. Furthermore, by simplifying the amino acid repertoire of the peptide, we successfully created the DPBB fold with only seven amino acid types (Ala, Asp, Glu, Gly, Lys, Arg, and Val), which can be coded by only GNN and ARR (R = A or G) codons in the modern translation system. Thus, the DPBB fold could have been materialized by the early translation system and genetic code.
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Affiliation(s)
- Sota Yagi
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Aditya K Padhi
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Jelena Vucinic
- Université Fédérale de Toulouse, ANITI, INRAE-UR 875, 31000 Toulouse, France.,TBI, Université Fédérale de Toulouse, CNRS, INRAE, INSA, ANITI, 31000 Toulouse, France.,Université Fédérale de Toulouse, ANITI, IRIT-UMR 5505, 31000 Toulouse, France
| | - Sophie Barbe
- TBI, Université Fédérale de Toulouse, CNRS, INRAE, INSA, ANITI, 31000 Toulouse, France
| | - Thomas Schiex
- Université Fédérale de Toulouse, ANITI, INRAE-UR 875, 31000 Toulouse, France
| | - Reiko Nakagawa
- RIKEN Center for Biosystems Dynamics Research, 2-2-3 Minatojima-minamimachi, Chuo-ku, Kobe, Hyogo 650-0047, Japan
| | - David Simoncini
- Université Fédérale de Toulouse, ANITI, IRIT-UMR 5505, 31000 Toulouse, France
| | - Kam Y J Zhang
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
| | - Shunsuke Tagami
- RIKEN Center for Biosystems Dynamics Research, 1-7-22 Suehiro-cho, Tsurumi-ku, Yokohama, Kanagawa 230-0045, Japan
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10
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Kirst H, Kerfeld CA. Clues to the function of bacterial microcompartments from ancillary genes. Biochem Soc Trans 2021; 49:1085-1098. [PMID: 34196367 PMCID: PMC8517908 DOI: 10.1042/bst20200632] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/13/2021] [Revised: 06/02/2021] [Accepted: 06/04/2021] [Indexed: 01/14/2023]
Abstract
Bacterial microcompartments (BMCs) are prokaryotic organelles. Their bounding membrane is a selectively permeable protein shell, encapsulating enzymes of specialized metabolic pathways. While the function of a BMC is dictated by the encapsulated enzymes which vary with the type of the BMC, the shell is formed by conserved protein building blocks. The genes necessary to form a BMC are typically organized in a locus; they encode the shell proteins, encapsulated enzymes as well as ancillary proteins that integrate the BMC function into the cell's metabolism. Among these are transcriptional regulators which usually found at the beginning or end of a locus, and transmembrane proteins that presumably function to conduct the BMC substrate into the cell. Here, we describe the types of transcriptional regulators and permeases found in association with BMC loci, using a recently collected data set of more than 7000 BMC loci distributed over 45 bacterial phyla, including newly discovered BMC loci. We summarize the known BMC regulation mechanisms, and highlight how much remains to be uncovered. We also show how analysis of these ancillary proteins can inform hypotheses about BMC function; by examining the ligand-binding domain of the regulator and the transporter, we propose that nucleotides are the likely substrate for an enigmatic uncharacterized BMC of unknown function.
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Affiliation(s)
- Henning Kirst
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, U.S.A
| | - Cheryl A Kerfeld
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, U.S.A
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI 48824, U.S.A
- Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, East Lansing, MI 48824, U.S.A
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11
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Sutter M, Melnicki MR, Schulz F, Woyke T, Kerfeld CA. A catalog of the diversity and ubiquity of bacterial microcompartments. Nat Commun 2021; 12:3809. [PMID: 34155212 PMCID: PMC8217296 DOI: 10.1038/s41467-021-24126-4] [Citation(s) in RCA: 50] [Impact Index Per Article: 16.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/26/2021] [Accepted: 05/28/2021] [Indexed: 12/25/2022] Open
Abstract
Bacterial microcompartments (BMCs) are organelles that segregate segments of metabolic pathways which are incompatible with surrounding metabolism. BMCs consist of a selectively permeable shell, composed of three types of structurally conserved proteins, together with sequestered enzymes that vary among functionally distinct BMCs. Genes encoding shell proteins are typically clustered with those for the encapsulated enzymes. Here, we report that the number of identifiable BMC loci has increased twenty-fold since the last comprehensive census of 2014, and the number of distinct BMC types has doubled. The new BMC types expand the range of compartmentalized catalysis and suggest that there is more BMC biochemistry yet to be discovered. Our comprehensive catalog of BMCs provides a framework for their identification, correlation with bacterial niche adaptation, experimental characterization, and development of BMC-based nanoarchitectures for biomedical and bioengineering applications. Bacterial microcompartments (BMCs) are organelles consisting of a protein shell in which certain metabolic reactions take place separated from the cytoplasm. Here, Sutter et al. present a comprehensive catalog of BMC loci, substantially expanding the number of known BMCs and describing distinct types and compartmentalized reactions.
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Affiliation(s)
- Markus Sutter
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrative Bioimaging Divisions, Lawrence Berkeley National Laboratory, Berkeley, CA, USA.,MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
| | - Matthew R Melnicki
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
| | - Frederik Schulz
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Tanja Woyke
- DOE Joint Genome Institute, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
| | - Cheryl A Kerfeld
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrative Bioimaging Divisions, Lawrence Berkeley National Laboratory, Berkeley, CA, USA. .,MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA. .,Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA.
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12
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Stewart KL, Stewart AM, Bobik TA. Prokaryotic Organelles: Bacterial Microcompartments in E. coli and Salmonella. EcoSal Plus 2020; 9:10.1128/ecosalplus.ESP-0025-2019. [PMID: 33030141 PMCID: PMC7552817 DOI: 10.1128/ecosalplus.esp-0025-2019] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Indexed: 02/07/2023]
Abstract
Bacterial microcompartments (MCPs) are proteinaceous organelles consisting of a metabolic pathway encapsulated within a selectively permeable protein shell. Hundreds of species of bacteria produce MCPs of at least nine different types, and MCP metabolism is associated with enteric pathogenesis, cancer, and heart disease. This review focuses chiefly on the four types of catabolic MCPs (metabolosomes) found in Escherichia coli and Salmonella: the propanediol utilization (pdu), ethanolamine utilization (eut), choline utilization (cut), and glycyl radical propanediol (grp) MCPs. Although the great majority of work done on catabolic MCPs has been carried out with Salmonella and E. coli, research outside the group is mentioned where necessary for a comprehensive understanding. Salient characteristics found across MCPs are discussed, including enzymatic reactions and shell composition, with particular attention paid to key differences between classes of MCPs. We also highlight relevant research on the dynamic processes of MCP assembly, protein targeting, and the mechanisms that underlie selective permeability. Lastly, we discuss emerging biotechnology applications based on MCP principles and point out challenges, unanswered questions, and future directions.
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Affiliation(s)
- Katie L. Stewart
- The Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, USA 50011
| | - Andrew M. Stewart
- The Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, USA 50011
| | - Thomas A. Bobik
- The Roy J. Carver Department of Biochemistry, Biophysics and Molecular Biology, Iowa State University, Ames, IA, USA 50011
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13
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Kerfeld CA, Sutter M. Engineered bacterial microcompartments: apps for programming metabolism. Curr Opin Biotechnol 2020; 65:225-232. [PMID: 32554213 PMCID: PMC7719235 DOI: 10.1016/j.copbio.2020.05.001] [Citation(s) in RCA: 16] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/25/2020] [Revised: 05/04/2020] [Accepted: 05/06/2020] [Indexed: 12/12/2022]
Abstract
Bacterial Microcompartments (BMCs) are used by diverse bacteria to compartmentalize enzymatic reactions, functioning analogously to the organelles of eukaryotes. The bounding membrane and encapsulated components are composed entirely of protein, which makes them ideal targets for modification by genetic engineering. In contrast to viruses, in which generally only one protein forms the capsid, the shells of BMCs consist of a variety of shell proteins, each a potential unit of selection. Despite their differences in permeability, the shell proteins are surprisingly interchangeable. Recent developments have shown that they are also highly amenable to engineered modifications which poise them for a variety of biotechnological applications. Given their modular structure, with a module defined as a semi-autonomous functional unit, BMCs can be considered apps for programming metabolism that can be de-bugged by adaptive evolution.
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Affiliation(s)
- Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory and Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, USA; Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA.
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory and Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI, USA; Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
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14
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Kalnins G, Cesle EE, Jansons J, Liepins J, Filimonenko A, Tars K. Encapsulation mechanisms and structural studies of GRM2 bacterial microcompartment particles. Nat Commun 2020; 11:388. [PMID: 31959751 PMCID: PMC6971018 DOI: 10.1038/s41467-019-14205-y] [Citation(s) in RCA: 33] [Impact Index Per Article: 8.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/25/2019] [Accepted: 12/18/2019] [Indexed: 11/08/2022] Open
Abstract
Bacterial microcompartments (BMCs) are prokaryotic organelles consisting of a protein shell and an encapsulated enzymatic core. BMCs are involved in several biochemical processes, such as choline, glycerol and ethanolamine degradation and carbon fixation. Since non-native enzymes can also be encapsulated in BMCs, an improved understanding of BMC shell assembly and encapsulation processes could be useful for synthetic biology applications. Here we report the isolation and recombinant expression of BMC structural genes from the Klebsiella pneumoniae GRM2 locus, the investigation of mechanisms behind encapsulation of the core enzymes, and the characterization of shell particles by cryo-EM. We conclude that the enzymatic core is encapsulated in a hierarchical manner and that the CutC choline lyase may play a secondary role as an adaptor protein. We also present a cryo-EM structure of a pT = 4 quasi-symmetric icosahedral shell particle at 3.3 Å resolution, and demonstrate variability among the minor shell forms.
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Affiliation(s)
- Gints Kalnins
- Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga, 1067, Latvia.
| | - Eva-Emilija Cesle
- Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga, 1067, Latvia
| | - Juris Jansons
- Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga, 1067, Latvia
| | - Janis Liepins
- Institute of Microbiology and Biotechnology, University of Latvia, Jelgavas 1, Riga, 1004, Latvia
| | - Anatolij Filimonenko
- Central European Institute of Technology, Masaryk University, Kamenice 753/5, 62500, Brno, Czech Republic
| | - Kaspars Tars
- Latvian Biomedical Research and Study Centre, Ratsupites 1, Riga, 1067, Latvia
- University of Latvia, Jelgavas 1, Riga, 1004, Latvia
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15
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Kirst H, Kerfeld CA. Bacterial microcompartments: catalysis-enhancing metabolic modules for next generation metabolic and biomedical engineering. BMC Biol 2019; 17:79. [PMID: 31601225 PMCID: PMC6787980 DOI: 10.1186/s12915-019-0691-z] [Citation(s) in RCA: 21] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/22/2019] [Accepted: 08/23/2019] [Indexed: 12/15/2022] Open
Abstract
Bacterial cells have long been thought to be simple cells with little spatial organization, but recent research has shown that they exhibit a remarkable degree of subcellular differentiation. Indeed, bacteria even have organelles such as magnetosomes for sensing magnetic fields or gas vesicles controlling cell buoyancy. A functionally diverse group of bacterial organelles are the bacterial microcompartments (BMCs) that fulfill specialized metabolic needs. Modification and reengineering of these BMCs enable innovative approaches for metabolic engineering and nanomedicine.
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Affiliation(s)
- Henning Kirst
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI, 48824, USA.,Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI, 48824, USA. .,Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA. .,Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, East Lansing, MI, 48824, USA.
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16
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Ravcheev DA, Moussu L, Smajic S, Thiele I. Comparative Genomic Analysis Reveals Novel Microcompartment-Associated Metabolic Pathways in the Human Gut Microbiome. Front Genet 2019; 10:636. [PMID: 31333721 PMCID: PMC6620236 DOI: 10.3389/fgene.2019.00636] [Citation(s) in RCA: 18] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2019] [Accepted: 06/18/2019] [Indexed: 12/16/2022] Open
Abstract
Bacterial microcompartments are self-assembling subcellular structures surrounded by a semipermeable protein shell and found only in bacteria, but not archaea or eukaryotes. The general functions of the bacterial microcompartments are to concentrate enzymes, metabolites, and cofactors for multistep pathways; maintain the cofactor ratio; protect the cell from toxic metabolic intermediates; and protect the encapsulated pathway from unwanted side reactions. The bacterial microcompartments were suggested to play a significant role in organisms of the human gut microbiome, especially for various pathogens. Here, we used a comparative genomics approach to analyze the bacterial microcompartments in 646 individual genomes of organisms commonly found in the human gut microbiome. The bacterial microcompartments were found in 150 (23.2%) analyzed genomes. These microcompartments include previously known ones for the utilization of ethanolamine, 1,2-propanediol, choline, and fucose/rhamnose. Moreover, we reconstructed two novel pathways associated with the bacterial microcompartments. These pathways are catabolic pathways for the utilization of 1-amino-2-propanol/1-amino-2-propanone and xanthine. Remarkably, the xanthine utilization pathway does not demonstrate similarity to previously known microcompartment-associated pathways. Thus, we describe a novel type of bacterial microcompartment.
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Affiliation(s)
- Dmitry A Ravcheev
- School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland.,Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Lubin Moussu
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Semra Smajic
- Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg
| | - Ines Thiele
- School of Medicine, National University of Ireland, Galway, University Road, Galway, Ireland.,Luxembourg Centre for Systems Biomedicine, University of Luxembourg, Esch-sur-Alzette, Luxembourg.,Discipline of Microbiology, School of Natural Sciences, National University of Ireland, Galway, University Road, Galway, Ireland
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17
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Ferlez B, Sutter M, Kerfeld CA. A designed bacterial microcompartment shell with tunable composition and precision cargo loading. Metab Eng 2019; 54:286-291. [PMID: 31075444 PMCID: PMC6884132 DOI: 10.1016/j.ymben.2019.04.011] [Citation(s) in RCA: 31] [Impact Index Per Article: 6.2] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/04/2019] [Revised: 04/09/2019] [Accepted: 04/24/2019] [Indexed: 12/31/2022]
Abstract
Microbes often augment their metabolism by conditionally constructing proteinaceous organelles, known as bacterial microcompartments (BMCs), that encapsulate enzymes to degrade organic compounds or assimilate CO2. BMCs self-assemble and are spatially delimited by a semi-permeable shell made up of hexameric, trimeric, and pentameric shell proteins. Bioengineers aim to recapitulate the organization and efficiency of these complex biological architectures by redesigning the shell to incorporate non-native enzymes from biotechnologically relevant pathways. To meet this challenge, a diverse set of synthetic biology tools are required, including methods to manipulate the properties of the shell as well as target and organize cargo encapsulation. We designed and determined the crystal structure of a synthetic shell protein building block with an inverted sidedness of its N- and C-terminal residues relative to its natural counterpart; the inversion targets genetically fused protein cargo to the lumen of the shell. Moreover, the titer of fluorescent protein cargo encapsulated using this strategy is controllable using an inducible tetracycline promoter. These results expand the available set of building blocks for precision engineering of BMC-based nanoreactors and are compatible with orthogonal methods which will facilitate the installation and organization of multi-enzyme pathways.
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Affiliation(s)
- Bryan Ferlez
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, East Lansing, MI 48824, USA
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, East Lansing, MI 48824, USA; Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI 48824, USA; Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, East Lansing, MI 48824, USA; Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA.
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18
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Bio-engineering of bacterial microcompartments: a mini review. Biochem Soc Trans 2019; 47:765-777. [DOI: 10.1042/bst20170564] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/26/2019] [Revised: 05/09/2019] [Accepted: 05/22/2019] [Indexed: 12/30/2022]
Abstract
AbstractBacterial microcompartments (BMCs) are protein-bound prokaryotic organelles, discovered in cyanobacteria more than 60 years ago. Functionally similar to eukaryotic cellular organelles, BMCs compartment metabolic activities in the cytoplasm, foremost to increase local enzyme concentration and prevent toxic intermediates from damaging the cytosolic content. Advanced knowledge of the functional and structural properties of multiple types of BMCs, particularly over the last 10 years, have highlighted design principles of microcompartments. This has prompted new research into their potential to function as programmable synthetic nano-bioreactors and novel bio-materials with biotechnological and medical applications. Moreover, due to the involvement of microcompartments in bacterial pathogenesis and human health, BMCs have begun to gain attention as potential novel drug targets. This mini-review gives an overview of important synthetic biology developments in the bioengineering of BMCs and a perspective on future directions in the field.
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19
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Characterization of a Glycyl Radical Enzyme Bacterial Microcompartment Pathway in Rhodobacter capsulatus. J Bacteriol 2019; 201:JB.00343-18. [PMID: 30510145 DOI: 10.1128/jb.00343-18] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/06/2018] [Accepted: 11/15/2018] [Indexed: 11/20/2022] Open
Abstract
Bacterial microcompartments (BMCs) are large (∼100-nm) protein shells that encapsulate enzymes, their substrates, and cofactors for the purposes of increasing metabolic reaction efficiency and protecting cells from toxic intermediates. The best-studied microcompartment is the carbon-fixing carboxysome that encapsulates ribulose-1,5-bisphosphate carboxylase and carbonic anhydrase. Other well-known BMCs include the Pdu and Eut BMCs, which metabolize 1,2-propanediol and ethanolamine, respectively, with vitamin B12-dependent diol dehydratase enzymes. Recent bioinformatic analyses identified a new prevalent type of BMC, hypothesized to utilize vitamin B12-independent glycyl radical enzymes to metabolize substrates. Here we use genetic and metabolic analyses to undertake in vivo characterization of the newly identified glycyl radical enzyme microcompartment 3 (GRM3) class of microcompartment clusters. Transcriptome sequencing analyses showed that the microcompartment gene cluster in the genome of the purple photosynthetic bacterium Rhodobacter capsulatus was expressed under dark anaerobic respiratory conditions in the presence of 1,2-propanediol. High-performance liquid chromatography and gas chromatography-mass spectrometry analyses showed that enzymes coded by this cluster metabolized 1,2-propanediol into propionaldehyde, propanol, and propionate. Surprisingly, the microcompartment pathway did not protect these cells from toxic propionaldehyde under the conditions used in this study, with buildup of this intermediate contributing to arrest of cell growth. We further show that expression of microcompartment genes is regulated by a two-component system located downstream of the microcompartment cluster.IMPORTANCE BMCs are protein shells that are designed to compartmentalize enzymatic reactions that require either sequestration of a substrate or the sequestration of toxic intermediates. Due to their ability to compartmentalize reactions, BMCs have also become attractive targets for bioengineering novel enzymatic reactions. Despite these useful features, little is known about the biochemistry of newly identified classes of BMCs. In this study, we have undertaken genetic and in vivo metabolic analyses of the newly identified GRM3 gene cluster.
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20
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Ferlez B, Sutter M, Kerfeld CA. Glycyl Radical Enzyme-Associated Microcompartments: Redox-Replete Bacterial Organelles. mBio 2019; 10:e02327-18. [PMID: 30622187 PMCID: PMC6325248 DOI: 10.1128/mbio.02327-18] [Citation(s) in RCA: 25] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2018] [Accepted: 11/28/2018] [Indexed: 12/31/2022] Open
Abstract
An increasing number of microbes are being identified that organize catabolic pathways within self-assembling proteinaceous structures known as bacterial microcompartments (BMCs). Most BMCs are characterized by their singular substrate specificity and commonly employ B12-dependent radical mechanisms. In contrast, a less-well-known BMC type utilizes the B12-independent radical chemistry of glycyl radical enzymes (GREs). Unlike B12-dependent enzymes, GREs require an activating enzyme (AE) as well as an external source of electrons to generate an adenosyl radical and form their catalytic glycyl radical. Organisms encoding these glycyl radical enzyme-associated microcompartments (GRMs) confront the challenge of coordinating the activation and maintenance of their GREs with the assembly of a multienzyme core that is encapsulated in a protein shell. The GRMs appear to enlist redox proteins to either generate reductants internally or facilitate the transfer of electrons from the cytosol across the shell. Despite this relative complexity, GRMs are one of the most widespread types of BMC, with distinct subtypes to catabolize different substrates. Moreover, they are encoded by many prominent gut-associated and pathogenic bacteria. In this review, we will focus on the diversity, function, and physiological importance of GRMs, with particular attention given to their associated and enigmatic redox proteins.
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Affiliation(s)
- Bryan Ferlez
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, Berkeley, California, USA
| | - Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, Michigan, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, Michigan, USA
- Environmental Genomics and Systems Biology and Molecular Biophysics and Integrated Bioimaging Divisions, Lawrence Berkeley National Laboratory, Berkeley, California, USA
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21
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Mallette E, Kimber MS. Structural and kinetic characterization of ( S)-1-amino-2-propanol kinase from the aminoacetone utilization microcompartment of Mycobacterium smegmatis. J Biol Chem 2018; 293:19909-19918. [PMID: 30361441 DOI: 10.1074/jbc.ra118.005485] [Citation(s) in RCA: 13] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/21/2018] [Revised: 10/23/2018] [Indexed: 12/22/2022] Open
Abstract
Bacterial microcompartments encapsulate enzymatic pathways that generate small, volatile, aldehyde intermediates. The Rhodococcus and Mycobacterium microcompartment (RMM) operon from Mycobacterium smegmatis encodes four enzymes, including (S)-1-amino-2-propanol dehydrogenase and a likely propionaldehyde dehydrogenase. We show here that a third enzyme (and its nonmicrocompartment-associated paralog) is a moderately specific (S)-1-amino-2-propanol kinase. We determined the structure of apo-aminopropanol kinase at 1.35 Å, revealing that it has structural similarity to hexosamine kinases, choline kinases, and aminoglycoside phosphotransferases. We modeled substrate binding, and tested our model by characterizing key enzyme variants. Bioinformatics analysis established that this enzyme is widespread in Actinobacteria, Proteobacteria, and Firmicutes, and is very commonly associated with a candidate phospholyase. In Rhizobia, aminopropanol kinase is generally associated with aromatic degradation pathways. In the RMM (and the parallel pathway that includes the second paralog), aminopropanol kinase likely degrades aminoacetone through a propanolamine-phosphate phospho-lyase-dependent pathway. These enzymatic activities were originally described in Pseudomonas, but the proteins responsible have not been previously identified. Bacterial microcompartments typically co-encapsulate enzymes which can regenerate required co-factors, but the RMM enzymes require four biochemically distinct co-factors with no overlap. This suggests that either the RMM shell can uniquely transport multiple co-factors in stoichiometric quantities, or that all enzymes except the phospho-lyase reside outside of the shell. In summary, aminopropanol kinase is a novel enzyme found in diverse bacteria and multiple metabolic pathways; its presence in the RMM implies that this microcompartment degrades aminoacetone, using a pathway that appears to violate some established precepts as to how microcompartments function.
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Affiliation(s)
- Evan Mallette
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
| | - Matthew S Kimber
- From the Department of Molecular and Cellular Biology, University of Guelph, Guelph, Ontario N1G 2W1, Canada
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22
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Biotechnological Advances in Bacterial Microcompartment Technology. Trends Biotechnol 2018; 37:325-336. [PMID: 30236905 DOI: 10.1016/j.tibtech.2018.08.006] [Citation(s) in RCA: 34] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/22/2018] [Revised: 08/22/2018] [Accepted: 08/23/2018] [Indexed: 12/22/2022]
Abstract
Bacterial microcompartments (BMCs) represent proteinaceous macromolecular nanobioreactors that are found in a broad range of bacteria, and which are associated with either anabolic or catabolic processes. They consist of a semipermeable outer shell that packages a central metabolic enzyme or pathway, providing both enhanced flux and protection against toxic intermediates. Recombinant production of BMCs has led to their repurposing with the incorporation of altogether new pathways. Deconstructing BMCs into their component parts has shown that some individual shell proteins self-associate into filaments that can be further modified into a cytoplasmic scaffold, or cytoscaffold, to which enzymes/proteins can be targeted. BMCs therefore represent a modular system that is highly suited for engineering biological systems for useful purposes.
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23
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Hagen A, Sutter M, Sloan N, Kerfeld CA. Programmed loading and rapid purification of engineered bacterial microcompartment shells. Nat Commun 2018; 9:2881. [PMID: 30038362 PMCID: PMC6056538 DOI: 10.1038/s41467-018-05162-z] [Citation(s) in RCA: 78] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/22/2018] [Accepted: 06/15/2018] [Indexed: 12/30/2022] Open
Abstract
Bacterial microcompartments (BMCs) are selectively permeable proteinaceous organelles which encapsulate segments of metabolic pathways across bacterial phyla. They consist of an enzymatic core surrounded by a protein shell composed of multiple distinct proteins. Despite great potential in varied biotechnological applications, engineering efforts have been stymied by difficulties in their isolation and characterization and a dearth of robust methods for programming cores and shell permeability. We address these challenges by functionalizing shell proteins with affinity handles, enabling facile complementation-based affinity purification (CAP) and specific cargo docking sites for efficient encapsulation via covalent-linkage (EnCo). These shell functionalizations extend our knowledge of BMC architectural principles and enable the development of minimal shell systems of precisely defined structure and composition. The generalizability of CAP and EnCo will enable their application to functionally diverse microcompartment systems to facilitate both characterization of natural functions and the development of bespoke shells for selectively compartmentalizing proteins.
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Affiliation(s)
- Andrew Hagen
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Markus Sutter
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA.,MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI, 48824, USA
| | - Nancy Sloan
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA
| | - Cheryl A Kerfeld
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA, 94720, USA. .,MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI, 48824, USA. .,Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, East Lansing, MI, 48824, USA.
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24
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Plegaria JS, Kerfeld CA. Engineering nanoreactors using bacterial microcompartment architectures. Curr Opin Biotechnol 2018; 51:1-7. [PMID: 29035760 PMCID: PMC5899066 DOI: 10.1016/j.copbio.2017.09.005] [Citation(s) in RCA: 27] [Impact Index Per Article: 4.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2017] [Accepted: 09/19/2017] [Indexed: 12/30/2022]
Abstract
Bacterial microcompartments (BMCs) are organelles that encapsulate enzymes involved in CO2 fixation or carbon catabolism in a selectively permeable protein shell. Here, we highlight recent advances in the bioengineering of these protein-based nanoreactors in heterologous systems, including transfer and expression of BMC gene clusters, the production of template empty shells, and the encapsulation of non-native enzymes.
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Affiliation(s)
- Jefferson S Plegaria
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
| | - Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA; Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA; Department of Biochemistry & Molecular Biology, Michigan State University, East Lansing, MI 48824, USA; Berkeley Synthetic Biology Institute, Berkeley, CA 94720, USA.
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25
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Abstract
Bacterial microcompartments (BMCs) are self-assembling organelles that consist of an enzymatic core that is encapsulated by a selectively permeable protein shell. The potential to form BMCs is widespread and found across the kingdom Bacteria. BMCs have crucial roles in carbon dioxide fixation in autotrophs and the catabolism of organic substrates in heterotrophs. They contribute to the metabolic versatility of bacteria, providing a competitive advantage in specific environmental niches. Although BMCs were first visualized more than 60 years ago, it is mainly in the past decade that progress has been made in understanding their metabolic diversity and the structural basis of their assembly and function. This progress has not only heightened our understanding of their role in microbial metabolism but is also beginning to enable their use in a variety of applications in synthetic biology. In this Review, we focus on recent insights into the structure, assembly, diversity and function of BMCs.
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Affiliation(s)
- Cheryl A. Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Clement Aussignargues
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
| | - Jan Zarzycki
- Max-Planck-Institute for Terrestrial Microbiology, D-35043, Marburg, Germany
| | - Fei Cai
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI 48824, USA
- Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, Berkeley, CA 94720, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI 48824, USA
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26
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Kerfeld CA. A bioarchitectonic approach to the modular engineering of metabolism. Philos Trans R Soc Lond B Biol Sci 2018; 372:rstb.2016.0387. [PMID: 28808103 DOI: 10.1098/rstb.2016.0387] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Accepted: 03/05/2017] [Indexed: 01/13/2023] Open
Abstract
Dissociating the complexity of metabolic processes into modules is a shift in focus from the single gene/gene product to functional and evolutionary units spanning the scale of biological organization. When viewing the levels of biological organization through this conceptual lens, modules are found across the continuum: domains within proteins, co-regulated groups of functionally associated genes, operons, metabolic pathways and (sub)cellular compartments. Combining modules as components or subsystems of a larger system typically leads to increased complexity and the emergence of new functions. By virtue of their potential for 'plug and play' into new contexts, modules can be viewed as units of both evolution and engineering. Through consideration of lessons learned from recent efforts to install new metabolic modules into cells and the emerging understanding of the structure, function and assembly of protein-based organelles, bacterial microcompartments, a structural bioengineering approach is described: one that builds from an architectural vocabulary of protein domains. This bioarchitectonic approach to engineering cellular metabolism can be applied to microbial cell factories, used in the programming of members of synthetic microbial communities or used to attain additional levels of metabolic organization in eukaryotic cells for increasing primary productivity and as the foundation of a green economy.This article is part of the themed issue 'Enhancing photosynthesis in crop plants: targets for improvement'.
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Affiliation(s)
- Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI 48824, USA .,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA.,Department of Biochemistry and Molecular Biology, Michigan State University, 603 Wilson Road, East Lansing, MI 48824, USA.,Department of Plant and Microbial Biology, University of California, 111 Koshland Hall, Berkeley, CA 94720, USA
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Plegaria JS, Sutter M, Ferlez B, Aussignargues C, Niklas J, Poluektov OG, Fromwiller C, TerAvest M, Utschig LM, Tiede DM, Kerfeld CA. Structural and Functional Characterization of a Short-Chain Flavodoxin Associated with a Noncanonical 1,2-Propanediol Utilization Bacterial Microcompartment. Biochemistry 2017; 56:5679-5690. [PMID: 28956602 DOI: 10.1021/acs.biochem.7b00682] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/10/2023]
Abstract
Bacterial microcompartments (BMCs) are proteinaceous organelles that encapsulate enzymes involved in CO2 fixation (carboxysomes) or carbon catabolism (metabolosomes). Metabolosomes share a common core of enzymes and a distinct signature enzyme for substrate degradation that defines the function of the BMC (e.g., propanediol or ethanolamine utilization BMCs, or glycyl-radical enzyme microcompartments). Loci encoding metabolosomes also typically contain genes for proteins that support organelle function, such as regulation, transport of substrate, and cofactor (e.g., vitamin B12) synthesis and recycling. Flavoproteins are frequently among these ancillary gene products, suggesting that these redox active proteins play an undetermined function in many metabolosomes. Here, we report the first characterization of a BMC-associated flavodoxin (Fld1C), a small flavoprotein, derived from the noncanonical 1,2-propanediol utilization BMC locus (PDU1C) of Lactobacillus reuteri. The 2.0 Å X-ray structure of Fld1C displays the α/β flavodoxin fold, which noncovalently binds a single flavin mononucleotide molecule. Fld1C is a short-chain flavodoxin with redox potentials of -240 ± 3 mV oxidized/semiquinone and -344 ± 1 mV semiquinone/hydroquinone versus the standard hydrogen electrode at pH 7.5. It can participate in an electron transfer reaction with a photoreductant to form a stable semiquinone species. Collectively, our structural and functional results suggest that PDU1C BMCs encapsulate Fld1C to store and transfer electrons for the reactivation and/or recycling of the B12 cofactor utilized by the signature enzyme.
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Affiliation(s)
- Jefferson S Plegaria
- MSU-DOE Plant Research Laboratory, Michigan State University , East Lansing, Michigan 48824, United States
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University , East Lansing, Michigan 48824, United States.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States
| | - Bryan Ferlez
- MSU-DOE Plant Research Laboratory, Michigan State University , East Lansing, Michigan 48824, United States
| | - Clément Aussignargues
- MSU-DOE Plant Research Laboratory, Michigan State University , East Lansing, Michigan 48824, United States
| | - Jens Niklas
- Solar Energy Conversion Group, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Oleg G Poluektov
- Solar Energy Conversion Group, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Ciara Fromwiller
- MSU-DOE Plant Research Laboratory, Michigan State University , East Lansing, Michigan 48824, United States
| | - Michaela TerAvest
- Department of Biochemistry & Molecular Biology, Michigan State University , East Lansing, Michigan 48824, United States
| | - Lisa M Utschig
- Solar Energy Conversion Group, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - David M Tiede
- Solar Energy Conversion Group, Argonne National Laboratory , Argonne, Illinois 60439, United States
| | - Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University , East Lansing, Michigan 48824, United States.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory , Berkeley, California 94720, United States.,Department of Biochemistry & Molecular Biology, Michigan State University , East Lansing, Michigan 48824, United States.,Berkeley Synthetic Biology Institute , Berkeley, California 94720, United States
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28
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Zarzycki J, Sutter M, Cortina NS, Erb TJ, Kerfeld CA. In Vitro Characterization and Concerted Function of Three Core Enzymes of a Glycyl Radical Enzyme - Associated Bacterial Microcompartment. Sci Rep 2017; 7:42757. [PMID: 28202954 PMCID: PMC5311937 DOI: 10.1038/srep42757] [Citation(s) in RCA: 40] [Impact Index Per Article: 5.7] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2016] [Accepted: 01/13/2017] [Indexed: 11/09/2022] Open
Abstract
Many bacteria encode proteinaceous bacterial microcompartments (BMCs) that encapsulate sequential enzymatic reactions of diverse metabolic pathways. Well-characterized BMCs include carboxysomes for CO2-fixation, and propanediol- and ethanolamine-utilizing microcompartments that contain B12-dependent enzymes. Genes required to form BMCs are typically organized in gene clusters, which promoted their distribution across phyla by horizontal gene transfer. Recently, BMCs associated with glycyl radical enzymes (GREs) were discovered; these are widespread and comprise at least three functionally distinct types. Previously, we predicted one type of these GRE-associated microcompartments (GRMs) represents a B12-independent propanediol-utilizing BMC. Here we functionally and structurally characterize enzymes of the GRM of Rhodopseudomonas palustris BisB18 and demonstrate their concerted function in vitro. The GRM signature enzyme, the GRE, is a dedicated 1,2-propanediol dehydratase with a new type of intramolecular encapsulation peptide. It forms a complex with its activating enzyme and, in conjunction with an aldehyde dehydrogenase, converts 1,2-propanediol to propionyl-CoA. Notably, homologous GRMs are also encoded in pathogenic Escherichia coli strains. Our high-resolution crystal structures of the aldehyde dehydrogenase lead to a revised reaction mechanism. The successful in vitro reconstitution of a part of the GRM metabolism provides insights into the metabolic function and steps in the assembly of this BMC.
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Affiliation(s)
- Jan Zarzycki
- Max-Planck-Institute for Terrestrial Microbiology, Karl-von-Frisch-Str. 10, D-35043, Marburg, Germany
| | - Markus Sutter
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI 48824, USA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA
| | - Niña Socorro Cortina
- Max-Planck-Institute for Terrestrial Microbiology, Karl-von-Frisch-Str. 10, D-35043, Marburg, Germany
| | - Tobias J Erb
- Max-Planck-Institute for Terrestrial Microbiology, Karl-von-Frisch-Str. 10, D-35043, Marburg, Germany
| | - Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, 612 Wilson Road, East Lansing, MI 48824, USA.,Molecular Biophysics and Integrated Bioimaging Division, Lawrence Berkeley National Laboratory, 1 Cyclotron Road, Berkeley, CA 94720, USA.,Department of Biochemistry &Molecular Biology, Michigan State University, 603 Wilson Road, East Lansing, MI 48824, USA.,Berkeley Synthetic Biology Institute, Berkeley, CA, USA.,Department of Plant and Microbial Biology, University of California, 111 Koshland Hall, Berkeley, CA 94720, USA
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Gonzalez-Esquer CR, Newnham SE, Kerfeld CA. Bacterial microcompartments as metabolic modules for plant synthetic biology. THE PLANT JOURNAL : FOR CELL AND MOLECULAR BIOLOGY 2016; 87:66-75. [PMID: 26991644 DOI: 10.1111/tpj.13166] [Citation(s) in RCA: 21] [Impact Index Per Article: 2.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 01/21/2016] [Revised: 03/04/2016] [Accepted: 03/08/2016] [Indexed: 05/28/2023]
Abstract
Bacterial microcompartments (BMCs) are megadalton-sized protein assemblies that enclose segments of metabolic pathways within cells. They increase the catalytic efficiency of the encapsulated enzymes while sequestering volatile or toxic intermediates from the bulk cytosol. The first BMCs discovered were the carboxysomes of cyanobacteria. Carboxysomes compartmentalize the enzyme ribulose-1,5-bisphosphate carboxylase/oxygenase (RuBisCO) with carbonic anhydrase. They enhance the carboxylase activity of RuBisCO by increasing the local concentration of CO2 in the vicinity of the enzyme's active site. As a metabolic module for carbon fixation, carboxysomes could be transferred to eukaryotic organisms (e.g. plants) to increase photosynthetic efficiency. Within the scope of synthetic biology, carboxysomes and other BMCs hold even greater potential when considered a source of building blocks for the development of nanoreactors or three-dimensional scaffolds to increase the efficiency of either native or heterologously expressed enzymes. The carboxysome serves as an ideal model system for testing approaches to engineering BMCs because their expression in cyanobacteria provides a sensitive screen for form (appearance of polyhedral bodies) and function (ability to grow on air). We recount recent progress in the re-engineering of the carboxysome shell and core to offer a conceptual framework for the development of BMC-based architectures for applications in plant synthetic biology.
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Affiliation(s)
| | - Sarah E Newnham
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
| | - Cheryl A Kerfeld
- MSU-DOE Plant Research Laboratory, Michigan State University, East Lansing, MI, USA
- Physical Biosciences Division, Lawrence Berkeley National Laboratory, Berkeley, CA, USA
- Department of Biochemistry and Molecular Biology, Michigan State University, East Lansing, MI, USA
- Berkeley Synthetic Biology Institute, UC Berkeley, Berkeley, CA, USA
- Department of Plant and Microbial Biology, UC Berkeley, Berkeley, CA, USA
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