1
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Van de Steen A, Wilkinson HC, Dalby PA, Frank S. Encapsulation of Transketolase into In Vitro-Assembled Protein Nanocompartments Improves Thermal Stability. ACS APPLIED BIO MATERIALS 2024; 7:3660-3674. [PMID: 38835217 PMCID: PMC11190991 DOI: 10.1021/acsabm.3c01153] [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: 11/29/2023] [Revised: 05/16/2024] [Accepted: 05/20/2024] [Indexed: 06/06/2024]
Abstract
Protein compartments offer definitive structures with a large potential design space that are of particular interest for green chemistry and therapeutic applications. One family of protein compartments, encapsulins, are simple prokaryotic nanocompartments that self-assemble from a single monomer into selectively permeable cages of between 18 and 42 nm. Over the past decade, encapsulins have been developed for a diverse application portfolio utilizing their defined cargo loading mechanisms and repetitive surface display. Although it has been demonstrated that encapsulation of non-native cargo proteins provides protection from protease activity, the thermal effects arising from enclosing cargo within encapsulins remain poorly understood. This study aimed to establish a methodology for loading a reporter protein into thermostable encapsulins to determine the resulting stability change of the cargo. Building on previous in vitro reassembly studies, we first investigated the effectiveness of in vitro reassembly and cargo-loading of two size classes of encapsulins Thermotoga maritima T = 1 and Myxococcus xanthus T = 3, using superfolder Green Fluorescent Protein. We show that the empty T. maritima capsid reassembles with higher yield than the M. xanthus capsid and that in vitro loading promotes the formation of the M. xanthus T = 3 capsid form over the T = 1 form, while overloading with cargo results in malformed T. maritima T = 1 encapsulins. For the stability study, a Förster resonance energy transfer (FRET)-probed industrially relevant enzyme cargo, transketolase, was then loaded into the T. maritima encapsulin. Our results show that site-specific orthogonal FRET labels can reveal changes in thermal unfolding of encapsulated cargo, suggesting that in vitro loading of transketolase into the T. maritima T = 1 encapsulin shell increases the thermal stability of the enzyme. This work supports the move toward fully harnessing structural, spatial, and functional control of in vitro assembled encapsulins with applications in cargo stabilization.
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Affiliation(s)
| | | | - Paul A. Dalby
- Department of Biochemical
Engineering, University College London, Bernard Katz Building, Gower Street, London WC1E 6BT, U.K.
| | - Stefanie Frank
- Department of Biochemical
Engineering, University College London, Bernard Katz Building, Gower Street, London WC1E 6BT, U.K.
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2
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Szyszka TN, Andreas MP, Lie F, Miller LM, Adamson LSR, Fatehi F, Twarock R, Draper BE, Jarrold MF, Giessen TW, Lau YH. Point mutation in a virus-like capsid drives symmetry reduction to form tetrahedral cages. Proc Natl Acad Sci U S A 2024; 121:e2321260121. [PMID: 38722807 PMCID: PMC11098114 DOI: 10.1073/pnas.2321260121] [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: 12/06/2023] [Accepted: 03/25/2024] [Indexed: 05/18/2024] Open
Abstract
Protein capsids are a widespread form of compartmentalization in nature. Icosahedral symmetry is ubiquitous in capsids derived from spherical viruses, as this geometry maximizes the internal volume that can be enclosed within. Despite the strong preference for icosahedral symmetry, we show that simple point mutations in a virus-like capsid can drive the assembly of unique symmetry-reduced structures. Starting with the encapsulin from Myxococcus xanthus, a 180-mer bacterial capsid that adopts the well-studied viral HK97 fold, we use mass photometry and native charge detection mass spectrometry to identify a triple histidine point mutant that forms smaller dimorphic assemblies. Using cryoelectron microscopy, we determine the structures of a precedented 60-mer icosahedral assembly and an unexpected 36-mer tetrahedron that features significant geometric rearrangements around a new interaction surface between capsid protomers. We subsequently find that the tetrahedral assembly can be generated by triple-point mutation to various amino acids and that even a single histidine point mutation is sufficient to form tetrahedra. These findings represent a unique example of tetrahedral geometry when surveying all characterized encapsulins, HK97-like capsids, or indeed any virus-derived capsids reported in the Protein Data Bank, revealing the surprising plasticity of capsid self-assembly that can be accessed through minimal changes in the protein sequence.
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Affiliation(s)
- Taylor N. Szyszka
- School of Chemistry, The University of Sydney, Camperdown, NSW2006, Australia
- The University of Sydney Nano Institute, The University of Sydney, Camperdown, NSW2006, Australia
| | - Michael P. Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI48109
| | - Felicia Lie
- School of Chemistry, The University of Sydney, Camperdown, NSW2006, Australia
| | - Lohra M. Miller
- Chemistry Department, Indiana University, Bloomington, IN47405
| | | | - Farzad Fatehi
- Department of Mathematics, University of York, YorkYO10 5DD, United Kingdom
- York Cross-Disciplinary Centre for Systems Analysis, University of York, YorkYO10 5DD, United Kingdom
| | - Reidun Twarock
- Department of Mathematics, University of York, YorkYO10 5DD, United Kingdom
- York Cross-Disciplinary Centre for Systems Analysis, University of York, YorkYO10 5DD, United Kingdom
- Department of Biology, University of York, YorkYO10 5DD, United Kingdom
| | | | | | - Tobias W. Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI48109
| | - Yu Heng Lau
- School of Chemistry, The University of Sydney, Camperdown, NSW2006, Australia
- The University of Sydney Nano Institute, The University of Sydney, Camperdown, NSW2006, Australia
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3
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Dutcher CA, Andreas MP, Giessen TW. A two-component quasi-icosahedral protein nanocompartment with variable shell composition and irregular tiling. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.25.591138. [PMID: 38712103 PMCID: PMC11071501 DOI: 10.1101/2024.04.25.591138] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Protein shells or capsids are a widespread form of compartmentalization in nature. Viruses use protein capsids to protect and transport their genomes while many cellular organisms use protein shells for varied metabolic purposes. These protein-based compartments often exhibit icosahedral symmetry and consist of a small number of structural components with defined roles. Encapsulins are a prevalent protein-based compartmentalization strategy in prokaryotes. All encapsulins studied thus far consist of a single shell protein that adopts the viral HK97-fold. Here, we report the characterization of a Family 2B two-component encapsulin from Streptomyces lydicus. We show the differential assembly behavior of the two shell components and demonstrate their ability to co-assemble into mixed shells with variable shell composition. We determined the structures of both shell proteins using cryo-electron microscopy. Using 3D-classification and crosslinking studies, we highlight the irregular tiling of mixed shells. Our work expands the known assembly modes of HK97-fold proteins and lays the foundation for future functional and engineering studies on two-component encapsulins.
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Affiliation(s)
- Cassandra A. Dutcher
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Michael P. Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Tobias W. Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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Andreas MP, Giessen TW. The biosynthesis of the odorant 2-methylisoborneol is compartmentalized inside a protein shell. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.04.23.590730. [PMID: 38712110 PMCID: PMC11071394 DOI: 10.1101/2024.04.23.590730] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/08/2024]
Abstract
Terpenoids are the largest class of natural products, found across all domains of life. One of the most abundant bacterial terpenoids is the volatile odorant 2-methylisoborneol (2-MIB), partially responsible for the earthy smell of soil and musty taste of contaminated water. Many bacterial 2-MIB biosynthetic gene clusters were thought to encode a conserved transcription factor, named EshA in the model soil bacterium Streptomyces griseus . Here, we revise the function of EshA, now referred to as Sg Enc, and show that it is a Family 2B encapsulin shell protein. Using cryo-electron microscopy, we find that Sg Enc forms an icosahedral protein shell and encapsulates 2-methylisoborneol synthase (2-MIBS) as a cargo protein. Sg Enc contains a cyclic adenosine monophosphate (cAMP) binding domain (CBD)-fold insertion and a unique metal-binding domain, both displayed on the shell exterior. We show that Sg Enc CBDs do not bind cAMP. We find that 2-MIBS cargo loading is mediated by an N-terminal disordered cargo-loading domain and that 2-MIBS activity and Sg Enc shell structure are not modulated by cAMP. Our work redefines the function of EshA and establishes Family 2B encapsulins as cargo-loaded protein nanocompartments involved in secondary metabolite biosynthesis.
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5
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Jones JA, Andreas MP, Giessen TW. Structural basis for peroxidase encapsulation inside the encapsulin from the Gram-negative pathogen Klebsiella pneumoniae. Nat Commun 2024; 15:2558. [PMID: 38519509 PMCID: PMC10960027 DOI: 10.1038/s41467-024-46880-x] [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: 09/21/2023] [Accepted: 03/12/2024] [Indexed: 03/25/2024] Open
Abstract
Encapsulins are self-assembling protein nanocompartments capable of selectively encapsulating dedicated cargo proteins, including enzymes involved in iron storage, sulfur metabolism, and stress resistance. They represent a unique compartmentalization strategy used by many pathogens to facilitate specialized metabolic capabilities. Encapsulation is mediated by specific cargo protein motifs known as targeting peptides (TPs), though the structural basis for encapsulation of the largest encapsulin cargo class, dye-decolorizing peroxidases (DyPs), is currently unknown. Here, we characterize a DyP-containing encapsulin from the enterobacterial pathogen Klebsiella pneumoniae. By combining cryo-electron microscopy with TP and TP-binding site mutagenesis, we elucidate the molecular basis for cargo encapsulation. TP binding is mediated by cooperative hydrophobic and ionic interactions as well as shape complementarity. Our results expand the molecular understanding of enzyme encapsulation inside protein nanocompartments and lay the foundation for rationally modulating encapsulin cargo loading for biomedical and biotechnological applications.
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Affiliation(s)
- Jesse A Jones
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Michael P Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Tobias W Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.
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6
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Szyszka TN, Andreas MP, Lie F, Miller LM, Adamson LSR, Fatehi F, Twarock R, Draper BE, Jarrold MF, Giessen TW, Lau YH. Point mutation in a virus-like capsid drives symmetry reduction to form tetrahedral cages. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2024:2024.02.05.579038. [PMID: 38370832 PMCID: PMC10871247 DOI: 10.1101/2024.02.05.579038] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 02/20/2024]
Abstract
Protein capsids are a widespread form of compartmentalisation in nature. Icosahedral symmetry is ubiquitous in capsids derived from spherical viruses, as this geometry maximises the internal volume that can be enclosed within. Despite the strong preference for icosahedral symmetry, we show that simple point mutations in a virus-like capsid can drive the assembly of novel symmetry-reduced structures. Starting with the encapsulin from Myxococcus xanthus, a 180-mer bacterial capsid that adopts the well-studied viral HK97 fold, we use mass photometry and native charge detection mass spectrometry to identify a triple histidine point mutant that forms smaller dimorphic assemblies. Using cryo-EM, we determine the structures of a precedented 60-mer icosahedral assembly and an unprecedented 36-mer tetrahedron that features significant geometric rearrangements around a novel interaction surface between capsid protomers. We subsequently find that the tetrahedral assembly can be generated by triple point mutation to various amino acids, and that even a single histidine point mutation is sufficient to form tetrahedra. These findings represent the first example of tetrahedral geometry across all characterised encapsulins, HK97-like capsids, or indeed any virus-derived capsids reported in the Protein Data Bank, revealing the surprising plasticity of capsid self-assembly that can be accessed through minimal changes in protein sequence.
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Affiliation(s)
- Taylor N Szyszka
- School of Chemistry, The University of Sydney, Camperdown, NSW 2006, Australia
- The University of Sydney Nano Institute, The University of Sydney, Camperdown, NSW 2006, Australia
| | - Michael P Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Felicia Lie
- School of Chemistry, The University of Sydney, Camperdown, NSW 2006, Australia
| | - Lohra M Miller
- Chemistry Department, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN 47405, USA
| | - Lachlan S R Adamson
- School of Chemistry, The University of Sydney, Camperdown, NSW 2006, Australia
| | - Farzad Fatehi
- Department of Mathematics, University of York, York, UK
- York Cross-Disciplinary Centre for Systems Analysis, University of York, York, UK
| | - Reidun Twarock
- Department of Mathematics, University of York, York, UK
- York Cross-Disciplinary Centre for Systems Analysis, University of York, York, UK
- Department of Biology, University of York, York, UK
| | - Benjamin E Draper
- Megadalton Solutions Inc., 3750 E Bluebird Ln, Bloomington, IN 47401, USA
| | - Martin F Jarrold
- Chemistry Department, Indiana University, 800 E. Kirkwood Avenue, Bloomington, IN 47405, USA
| | - Tobias W Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Yu Heng Lau
- School of Chemistry, The University of Sydney, Camperdown, NSW 2006, Australia
- The University of Sydney Nano Institute, The University of Sydney, Camperdown, NSW 2006, Australia
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7
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Benisch R, Andreas MP, Giessen TW. A widespread bacterial protein compartment sequesters and stores elemental sulfur. SCIENCE ADVANCES 2024; 10:eadk9345. [PMID: 38306423 PMCID: PMC10836720 DOI: 10.1126/sciadv.adk9345] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 01/03/2024] [Indexed: 02/04/2024]
Abstract
Subcellular compartments often serve to store nutrients or sequester labile or toxic compounds. As bacteria mostly do not possess membrane-bound organelles, they often have to rely on protein-based compartments. Encapsulins are one of the most prevalent protein-based compartmentalization strategies found in prokaryotes. Here, we show that desulfurase encapsulins can sequester and store large amounts of crystalline elemental sulfur. We determine the 1.78-angstrom cryo-EM structure of a 24-nanometer desulfurase-loaded encapsulin. Elemental sulfur crystals can be formed inside the encapsulin shell in a desulfurase-dependent manner with l-cysteine as the sulfur donor. Sulfur accumulation can be influenced by the concentration and type of sulfur source in growth medium. The selectively permeable protein shell allows the storage of redox-labile elemental sulfur by excluding cellular reducing agents, while encapsulation substantially improves desulfurase activity and stability. These findings represent an example of a protein compartment able to accumulate and store elemental sulfur.
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Affiliation(s)
- Robert Benisch
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael P. Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Tobias W. Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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8
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Kwon S, Andreas MP, Giessen TW. Structure and heterogeneity of a highly cargo-loaded encapsulin shell. J Struct Biol 2023; 215:108022. [PMID: 37657675 DOI: 10.1016/j.jsb.2023.108022] [Citation(s) in RCA: 11] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2023] [Revised: 08/26/2023] [Accepted: 08/28/2023] [Indexed: 09/03/2023]
Abstract
Encapsulins are self-assembling protein nanocompartments able to selectively encapsulate dedicated cargo enzymes. Encapsulins are widespread across bacterial and archaeal phyla and are involved in oxidative stress resistance, iron storage, and sulfur metabolism. Encapsulin shells exhibit icosahedral geometry and consist of 60, 180, or 240 identical protein subunits. Cargo encapsulation is mediated by the specific interaction of targeting peptides or domains, found in all cargo proteins, with the interior surface of the encapsulin shell during shell self-assembly. Here, we report the 2.53 Å cryo-EM structure of a heterologously produced and highly cargo-loaded T3 encapsulin shell from Myxococcus xanthus and explore the systems' structural heterogeneity. We find that exceedingly high cargo loading results in the formation of substantial amounts of distorted and aberrant shells, likely caused by a combination of unfavorable steric clashes of cargo proteins and shell conformational changes. Based on our cryo-EM structure, we determine and analyze the targeting peptide-shell binding mode. We find that both ionic and hydrophobic interactions mediate targeting peptide binding. Our results will guide future attempts at rationally engineering encapsulins for biomedical and biotechnological applications.
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Affiliation(s)
- Seokmu Kwon
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael P Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Tobias W Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA.
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9
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Quinton AR, McDowell HB, Hoiczyk E. Encapsulins: Nanotechnology's future in a shell. ADVANCES IN APPLIED MICROBIOLOGY 2023; 125:1-48. [PMID: 38783722 DOI: 10.1016/bs.aambs.2023.09.001] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/25/2024]
Abstract
Encapsulins, virus capsid-like bacterial nanocompartments have emerged as promising tools in medicine, imaging, and material sciences. Recent work has shown that these protein-bound icosahedral 'organelles' possess distinct properties that make them exceptionally usable for nanotechnology applications. A key factor contributing to their appeal is their ability to self-assemble, coupled with their capacity to encapsulate a wide range of cargos. Their genetic manipulability, stability, biocompatibility, and nano-size further enhance their utility, offering outstanding possibilities for practical biotechnology applications. In particular, their amenability to engineering has led to their extensive modification, including the packaging of non-native cargos and the utilization of the shell surface for displaying immunogenic or targeting proteins and peptides. This inherent versatility, combined with the ease of expressing encapsulins in heterologous hosts, promises to provide broad usability. Although mostly not yet commercialized, encapsulins have started to demonstrate their vast potential for biotechnology, from drug delivery to biofuel production and the synthesis of valuable inorganic materials. In this review, we will initially discuss the structure, function and diversity of encapsulins, which form the basis for these emerging applications, before reviewing ongoing practical uses and highlighting promising applications in medicine, engineering and environmental sciences.
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Affiliation(s)
- Amy Ruth Quinton
- School of Biosciences, The Krebs Institute, The University of Sheffield, Sheffield, United Kingdom
| | - Harry Benjamin McDowell
- School of Biosciences, The Krebs Institute, The University of Sheffield, Sheffield, United Kingdom
| | - Egbert Hoiczyk
- School of Biosciences, The Krebs Institute, The University of Sheffield, Sheffield, United Kingdom.
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10
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Su Y, Liu B, Huang Z, Teng Z, Yang L, Zhu J, Huo S, Liu A. Virus-like particles nanoreactors: from catalysis towards bio-applications. J Mater Chem B 2023; 11:9084-9098. [PMID: 37697810 DOI: 10.1039/d3tb01112g] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 09/13/2023]
Abstract
Virus-like particles (VLPs) are self-assembled supramolecular structures found in nature, often used for compartmentalization. Exploiting their inherent properties, including precise nanoscale structures, monodispersity, and high stability, these architectures have been widely used as nanocarriers to protect or enrich catalysts, facilitating catalytic reactions and avoiding interference from the bulk solutions. In this review, we summarize the current progress of virus-like particles (VLPs)-based nanoreactors. First, we briefly introduce the physicochemical properties of the most commonly used virus particles to understand their roles in catalytic reactions beyond the confined space. Next, we summarize the self-assembly of nanoreactors forming higher-order hierarchical structures, highlighting the emerging field of nanoreactors as artificial organelles and their potential biomedical applications. Finally, we discuss the current findings and future perspectives of VLPs-based nanoreactors.
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Affiliation(s)
- Yuqing Su
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
| | - Beibei Liu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
| | - Zhenkun Huang
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
| | - Zihao Teng
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
| | - Liulin Yang
- State Key Laboratory of Physical Chemistry of Solid Surface, Key Laboratory of Chemical Biology of Fujian Province, College of Chemistry and Chemical Engineering, Xiamen University, Xiamen 361005, P. R. China
| | - Jie Zhu
- National-Local Joint Engineering Research and High-Quality Utilization, Changzhou University, Changzhou 213164, China
| | - Shuaidong Huo
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
| | - Aijie Liu
- Fujian Provincial Key Laboratory of Innovative Drug Target Research, School of Pharmaceutical Sciences, Xiamen University, Xiamen 361102, China.
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11
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Jones JA, Andreas MP, Giessen TW. Structural basis for peroxidase encapsulation in a protein nanocompartment. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.09.18.558302. [PMID: 37790520 PMCID: PMC10542125 DOI: 10.1101/2023.09.18.558302] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/05/2023]
Abstract
Encapsulins are self-assembling protein nanocompartments capable of selectively encapsulating dedicated cargo proteins, including enzymes involved in iron storage, sulfur metabolism, and stress resistance. They represent a unique compartmentalization strategy used by many pathogens to facilitate specialized metabolic capabilities. Encapsulation is mediated by specific cargo protein motifs known as targeting peptides (TPs), though the structural basis for encapsulation of the largest encapsulin cargo class, dye-decolorizing peroxidases (DyPs), is currently unknown. Here, we characterize a DyP-containing encapsulin from the enterobacterial pathogen Klebsiella pneumoniae. By combining cryo-electron microscopy with TP mutagenesis, we elucidate the molecular basis for cargo encapsulation. TP binding is mediated by cooperative hydrophobic and ionic interactions as well as shape complementarity. Our results expand the molecular understanding of enzyme encapsulation inside protein nanocompartments and lay the foundation for rationally modulating encapsulin cargo loading for biomedical and biotechnological applications.
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Affiliation(s)
- Jesse A. Jones
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Michael P. Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
| | - Tobias W. Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA
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12
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Kwon S, Andreas MP, Giessen TW. Structure and heterogeneity of a highly cargo-loaded encapsulin shell. BIORXIV : THE PREPRINT SERVER FOR BIOLOGY 2023:2023.07.26.550694. [PMID: 37546724 PMCID: PMC10402063 DOI: 10.1101/2023.07.26.550694] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 08/08/2023]
Abstract
Encapsulins are self-assembling protein nanocompartments able to selectively encapsulate dedicated cargo enzymes. Encapsulins are widespread across bacterial and archaeal phyla and are involved in oxidative stress resistance, iron storage, and sulfur metabolism. Encapsulin shells exhibit icosahedral geometry and consist of 60, 180, or 240 identical protein subunits. Cargo encapsulation is mediated by the specific interaction of targeting peptides or domains, found in all cargo proteins, with the interior surface of the encapsulin shell during shell self-assembly. Here, we report the 2.53 Å cryo-EM structure of a heterologously produced and highly cargo-loaded T3 encapsulin shell from Myxococcus xanthus and explore the systems' structural heterogeneity. We find that exceedingly high cargo loading results in the formation of substantial amounts of distorted and aberrant shells, likely caused by a combination of unfavorable steric clashes of cargo proteins and shell conformational changes. Based on our cryo-EM structure, we determine and analyze the targeting peptide-shell binding mode. We find that both ionic and hydrophobic interactions mediate targeting peptide binding. Our results will guide future attempts at rationally engineering encapsulins for biomedical and biotechnological applications.
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Affiliation(s)
- Seokmu Kwon
- Department of Chemical Engineering, University of Michigan, Ann Arbor, MI 48109, USA
| | - Michael P. Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
| | - Tobias W. Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI 48109, USA
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13
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Abstract
Encapsulins are a recently discovered class of prokaryotic self-assembling icosahedral protein nanocompartments measuring between 24 and 42 nm in diameter, capable of selectively encapsulating dedicated cargo proteins in vivo. They have been classified into four families based on sequence identity and operon structure, and thousands of encapsulin systems have recently been computationally identified across a wide range of bacterial and archaeal phyla. Cargo encapsulation is mediated by the presence of specific targeting motifs found in all native cargo proteins that interact with the interior surface of the encapsulin shell during self-assembly. Short C-terminal targeting peptides (TPs) are well documented in Family 1 encapsulins, while more recently, larger N-terminal targeting domains (TDs) have been discovered in Family 2. The modular nature of TPs and their facile genetic fusion to non-native cargo proteins of interest has made cargo encapsulation, both in vivo and in vitro, readily exploitable and has therefore resulted in a range of rationally engineered nano-compartmentalization systems. This review summarizes current knowledge on cargo protein encapsulation within encapsulins and highlights select studies that utilize TP fusions to non-native cargo in creative and useful ways.
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Affiliation(s)
- Jesse A Jones
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.
| | - Robert Benisch
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI, USA
| | - Tobias W Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, MI, USA.
- Program in Chemical Biology, University of Michigan, Ann Arbor, MI, USA
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14
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Wang R, Liu X, Lv B, Sun W, Li C. Designing Intracellular Compartments for Efficient Engineered Microbial Cell Factories. ACS Synth Biol 2023; 12:1378-1395. [PMID: 37083286 DOI: 10.1021/acssynbio.2c00671] [Citation(s) in RCA: 2] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 04/22/2023]
Abstract
With the rapid development of synthetic biology, various kinds of microbial cell factories (MCFs) have been successfully constructed to produce high-value-added compounds. However, the complexity of metabolic regulation and pathway crosstalk always cause issues such as intermediate metabolite accumulation, byproduct generation, and metabolic burden in MCFs, resulting in low efficiencies and low yields of industrial biomanufacturing. Such issues could be solved by spatially rearranging the pathways using intracellular compartments. In this review, design strategies are summarized and discussed based on the types and characteristics of natural and artificial subcellular compartments. This review systematically presents information for the construction of efficient MCFs with intracellular compartments in terms of four aspects of design strategy goals: (1) improving local reactant concentration; (2) intercepting and isolating competing pathways; (3) providing specific reaction substances and environments; and (4) storing and accumulating products.
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Affiliation(s)
- Ruwen Wang
- Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, PR China
| | - Xin Liu
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, PR China
| | - Bo Lv
- Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, PR China
| | - Wentao Sun
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, PR China
| | - Chun Li
- Key Laboratory of Medical Molecule Science and Pharmaceutical Engineering, Ministry of Industry and Information Technology, Institute of Biochemical Engineering, School of Chemistry and Chemical Engineering, Beijing Institute of Technology, Beijing, 100081, PR China
- Key Lab for Industrial Biocatalysis, Ministry of Education, Department of Chemical Engineering, Tsinghua University, Beijing, 100084, PR China
- Center for Synthetic and System Biology, Tsinghua University, Beijing, 100084, PR China
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15
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Liu M, Wang Y, Jiang H, Han Y, Xia J. Synthetic Multienzyme Assemblies for Natural Product Biosynthesis. Chembiochem 2023; 24:e202200518. [PMID: 36625563 DOI: 10.1002/cbic.202200518] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/08/2022] [Revised: 01/10/2023] [Accepted: 01/10/2023] [Indexed: 01/11/2023]
Abstract
In nature, enzymes that catalyze sequential reactions are often assembled as clusters or complexes. The formation of multienzyme complexes, or metabolons, brings the enzyme active sites into proximity to promote intermediate transfer, decrease intermediate leakage, and streamline the metabolic flux towards the desired products. We and others have developed synthetic versions of metabolons through various strategies to enhance the catalytic rates for synthesizing valuable chemicals inside microbes. Synthetic multienzyme complexes range from static enzyme nanostructures to dynamic enzyme coacervates. Enzyme complexation optimizes the metabolic fluxes inside microbes, increases the product titer, and supplies the field with high-yield microbe strains that are amenable to large-scale fermentation. Enzyme complexes constructed inside microbial cells can be separated as independent entities and catalyze biosynthetic reactions ex vivo; such a feature gains these complexes another name, "synthetic organelles" - new subcellular entities with independent structures and functions. Still, the field is seeking new strategies to better balance dynamicity and confinement and to achieve finer control of local compartmentalization in the cells, as the natural multienzyme complexes do. Industrial applications of synthetic multienzyme complexes for the large-scale production of valuable chemicals are yet to be realized. This review focuses on synthetic multienzyme complexes that are constructed and function inside microbial cells.
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Affiliation(s)
- Min Liu
- Department of Chemistry and, Center for Cell & Developmental Biology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Yue Wang
- Department of Chemistry and, Center for Cell & Developmental Biology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Hao Jiang
- Department of Chemistry and, Center for Cell & Developmental Biology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Yongxu Han
- Department of Chemistry and, Center for Cell & Developmental Biology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
| | - Jiang Xia
- Department of Chemistry and, Center for Cell & Developmental Biology, The Chinese University of Hong Kong, Shatin, Hong Kong SAR, China
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16
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Jones JA, Andreas MP, Giessen TW. Exploring the Extreme Acid Tolerance of a Dynamic Protein Nanocage. Biomacromolecules 2023; 24:1388-1399. [PMID: 36796007 DOI: 10.1021/acs.biomac.2c01424] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/18/2023]
Abstract
Encapsulins are microbial protein nanocages capable of efficient self-assembly and cargo enzyme encapsulation. Due to their favorable properties, including high thermostability, protease resistance, and robust heterologous expression, encapsulins have become popular bioengineering tools for applications in medicine, catalysis, and nanotechnology. Resistance against physicochemical extremes like high temperature and low pH is a highly desirable feature for many biotechnological applications. However, no systematic search for acid-stable encapsulins has been carried out, while the influence of pH on encapsulin shells has so far not been thoroughly explored. Here, we report on a newly identified encapsulin nanocage from the acid-tolerant bacterium Acidipropionibacterium acidipropionici. Using transmission electron microscopy, dynamic light scattering, and proteolytic assays, we demonstrate its extreme acid tolerance and resilience against proteases. We structurally characterize the novel nanocage using cryo-electron microscopy, revealing a dynamic five-fold pore that displays distinct "closed" and "open" states at neutral pH but only a singular "closed" state under strongly acidic conditions. Further, the "open" state exhibits the largest pore in an encapsulin shell reported to date. Non-native protein encapsulation capabilities are demonstrated, and the influence of external pH on internalized cargo is explored. Our results expand the biotechnological application range of encapsulin nanocages toward potential uses under strongly acidic conditions and highlight pH-responsive encapsulin pore dynamics.
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Affiliation(s)
- Jesse A Jones
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0624, United States
| | - Michael P Andreas
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0624, United States
| | - Tobias W Giessen
- Department of Biological Chemistry, University of Michigan Medical School, Ann Arbor, Michigan 48109-0624, United States
- Department of Biomedical Engineering, University of Michigan Medical School, Ann Arbor, Michigan 48109-1382, United States
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17
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Kraj P, Hewagama ND, Douglas T. Diffusion and molecular partitioning in hierarchically complex virus-like particles. Virology 2023; 580:50-60. [PMID: 36764014 DOI: 10.1016/j.virol.2023.01.012] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/11/2022] [Revised: 01/09/2023] [Accepted: 01/12/2023] [Indexed: 01/22/2023]
Abstract
Viruses are diverse infectious agents found in virtually every type of natural environment. Due to the range of conditions in which viruses have evolved, they exhibit a wide range of structure and function which has been exploited for biotechnology. The self-assembly process of virus-like particles (VLPs), derived from structural virus components, allows for the assembly of a hierarchy of materials. Because VLPs are robust in both their assembly and the final product, functionality can be incorporated through design of their building blocks or chemical modification after their synthesis and assembly. In particular, encapsulation of active enzymes inside VLP results in macromolecular concentration approximating that of cells, introducing excluded volume effects on encapsulated cargo which are not present in traditional experiments done on dilute proteins. This work reviews the hierarchical assembly of VLPs, experiments investigating diffusion in VLP systems, and methods for partitioning of chemical species in VLPs as functional biomaterials.
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Affiliation(s)
- Pawel Kraj
- Department of Chemistry, Indiana University, 800 E Kirkwood Ave., Bloomington, IN, 47405, USA
| | - Nathasha D Hewagama
- Department of Chemistry, Indiana University, 800 E Kirkwood Ave., Bloomington, IN, 47405, USA
| | - Trevor Douglas
- Department of Chemistry, Indiana University, 800 E Kirkwood Ave., Bloomington, IN, 47405, USA.
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18
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Ebensperger P, Zmyslia M, Lohner P, Braunreuther J, Deuringer B, Becherer A, Süss R, Fischer A, Jessen-Trefzer C. A Dual-Metal-Catalyzed Sequential Cascade Reaction in an Engineered Protein Cage. Angew Chem Int Ed Engl 2023; 62:e202218413. [PMID: 36799770 DOI: 10.1002/anie.202218413] [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: 12/13/2022] [Revised: 02/15/2023] [Accepted: 02/17/2023] [Indexed: 02/18/2023]
Abstract
Herein, we describe the creation of an artificial protein cage housing a dual-metal-tagged guest protein that catalyzes a linear, two-step sequential cascade reaction. The guest protein consists of a fusion protein of HaloTag and monomeric rhizavidin. Inside the protein capsid, we established a ruthenium-catalyzed allylcarbamate deprotection reaction followed by a gold-catalyzed ring-closing hydroamination reaction that led to indoles and phenanthridines with an overall yield of up to 66 % in aqueous solutions. Furthermore, we show that the encapsulation stabilizes the metal catalysts against deactivation by air, proteins and cell lysate.
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Affiliation(s)
- Paul Ebensperger
- Institute of Organic Chemistry, University of Freiburg, Alberstrasse 21, 79104, Freiburg i. Br., Germany
| | - Mariia Zmyslia
- Institute of Organic Chemistry, University of Freiburg, Alberstrasse 21, 79104, Freiburg i. Br., Germany
| | - Philipp Lohner
- Institute of Organic Chemistry, University of Freiburg, Alberstrasse 21, 79104, Freiburg i. Br., Germany
| | - Judith Braunreuther
- Institute of Organic Chemistry, University of Freiburg, Alberstrasse 21, 79104, Freiburg i. Br., Germany
| | - Benedikt Deuringer
- Institute of Pharmaceutical Science, University of Freiburg, Sonnenstrasse 5, 79104, Freiburg i. Br., Germany
| | - Anita Becherer
- Institute of Inorganic and Analytical Chemistry, University of Freiburg, Alberstrasse 21, 79104, Freiburg i. Br., Germany
| | - Regine Süss
- Institute of Pharmaceutical Science, University of Freiburg, Sonnenstrasse 5, 79104, Freiburg i. Br., Germany
| | - Anna Fischer
- Institute of Inorganic and Analytical Chemistry, University of Freiburg, Alberstrasse 21, 79104, Freiburg i. Br., Germany
| | - Claudia Jessen-Trefzer
- Institute of Organic Chemistry, University of Freiburg, Alberstrasse 21, 79104, Freiburg i. Br., Germany
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19
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Michel-Souzy S, Cornelissen JJLM. Modification and Production of Encapsulin. Methods Mol Biol 2023; 2671:157-169. [PMID: 37308645 DOI: 10.1007/978-1-0716-3222-2_10] [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] [Indexed: 06/14/2023]
Abstract
Encapsulins are a class of protein nanocages that are found in bacteria, which are easy to produce and engineer in E. coli expression systems. The encapsulin from Thermotoga maritima (Tm) is well studied, its structure is available, and without modification it is barely taken up by cells, making it promising candidates for targeted drug delivery. In recent years, encapsulins are engineered and studied for potential use as drug delivery carriers, imaging agents, and as nanoreactors. Consequently, it is important to be able to modify the surface of these encapsulins, for example, by inserting a peptide sequence for targeting or other functions. Ideally, this is combined with high production yields and straightforward purification methods. In this chapter, we describe a method to genetically modify the surface of Tm and Brevibacterium linens (Bl) encapsulins, as model systems, to purify them and characterize the obtain nanocages.
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Affiliation(s)
- Sandra Michel-Souzy
- Department of Molecules and Materials, MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands.
| | - Jeroen J L M Cornelissen
- Department of Molecules and Materials, MESA+ Institute for Nanotechnology, University of Twente, Enschede, The Netherlands.
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20
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Armstrong FA, Cheng B, Herold RA, Megarity CF, Siritanaratkul B. From Protein Film Electrochemistry to Nanoconfined Enzyme Cascades and the Electrochemical Leaf. Chem Rev 2022; 123:5421-5458. [PMID: 36573907 PMCID: PMC10176485 DOI: 10.1021/acs.chemrev.2c00397] [Citation(s) in RCA: 13] [Impact Index Per Article: 6.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
Abstract
Protein film electrochemistry (PFE) has given unrivalled insight into the properties of redox proteins and many electron-transferring enzymes, allowing investigations of otherwise ill-defined or intractable topics such as unstable Fe-S centers and the catalytic bias of enzymes. Many enzymes have been established to be reversible electrocatalysts when attached to an electrode, and further investigations have revealed how unusual dependences of catalytic rates on electrode potential have stark similarities with electronics. A special case, the reversible electrochemistry of a photosynthetic enzyme, ferredoxin-NADP+ reductase (FNR), loaded at very high concentrations in the 3D nanopores of a conducting metal oxide layer, is leading to a new technology that brings PFE to myriad enzymes of other classes, the activities of which become controlled by the primary electron exchange. This extension is possible because FNR-based recycling of NADP(H) can be coupled to a dehydrogenase, and thence to other enzymes linked in tandem by the tight channelling of cofactors and intermediates within the nanopores of the material. The earlier interpretations of catalytic wave-shapes and various analogies with electronics are thus extended to initiate a field perhaps aptly named "cascade-tronics", in which the flow of reactions along an enzyme cascade is monitored and controlled through an electrochemical analyzer. Unlike in photosynthesis where FNR transduces electron transfer and hydride transfer through the unidirectional recycling of NADPH, the "electrochemical leaf" (e-Leaf) can be used to drive reactions in both oxidizing and reducing directions. The e-Leaf offers a natural way to study how enzymes are affected by nanoconfinement and crowding, mimicking the physical conditions under which enzyme cascades operate in living cells. The reactions of the trapped enzymes, often at very high local concentration, are thus studied electrochemically, exploiting the potential domain to control rates and direction and the current-rate analogy to derive kinetic data. Localized NADP(H) recycling is very efficient, resulting in very high cofactor turnover numbers and new opportunities for controlling and exploiting biocatalysis.
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Affiliation(s)
- Fraser A. Armstrong
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Beichen Cheng
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Ryan A. Herold
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Clare F. Megarity
- Department of Chemistry, University of Oxford, South Parks Road, Oxford OX1 3QR, United Kingdom
| | - Bhavin Siritanaratkul
- Stephenson Institute for Renewable Energy and the Department of Chemistry, University of Liverpool, Liverpool L69 7ZF, United Kingdom
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21
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Kwon S, Giessen TW. Engineered Protein Nanocages for Concurrent RNA and Protein Packaging In Vivo. ACS Synth Biol 2022; 11:3504-3515. [PMID: 36170610 PMCID: PMC9944510 DOI: 10.1021/acssynbio.2c00391] [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] [Indexed: 01/31/2023]
Abstract
Protein nanocages have emerged as an important engineering platform for biotechnological and biomedical applications. Among naturally occurring protein cages, encapsulin nanocompartments have recently gained prominence due to their favorable physico-chemical properties, ease of shell modification, and highly efficient and selective intrinsic protein packaging capabilities. Here, we expand encapsulin function by designing and characterizing encapsulins for concurrent RNA and protein encapsulation in vivo. Our strategy is based on modifying encapsulin shells with nucleic acid-binding peptides without disrupting the native protein packaging mechanism. We show that our engineered encapsulins reliably self-assemble in vivo, are capable of efficient size-selective in vivo RNA packaging, can simultaneously load multiple functional RNAs, and can be used for concurrent in vivo packaging of RNA and protein. Our engineered encapsulation platform has potential for codelivery of therapeutic RNAs and proteins to elicit synergistic effects and as a modular tool for other biotechnological applications.
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Affiliation(s)
- Seokmu Kwon
- Department of Chemical Engineering, University of Michigan, Ann Arbor, Michigan 48109, United States
| | - Tobias W. Giessen
- Department of Biological Chemistry and Department of Biomedical Engineering, University of Michigan Medical School, Ann Arbor, Michigan 48109, United States
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22
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Tasneem N, Szyszka TN, Jenner EN, Lau YH. How Pore Architecture Regulates the Function of Nanoscale Protein Compartments. ACS NANO 2022; 16:8540-8556. [PMID: 35583458 DOI: 10.1021/acsnano.2c02178] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/15/2023]
Abstract
Self-assembling proteins can form porous compartments that adopt well-defined architectures at the nanoscale. In nature, protein compartments act as semipermeable barriers to enable spatial separation and organization of complex biochemical processes. The compartment pores play a key role in their overall function by selectively controlling the influx and efflux of important biomolecular species. By engineering the pores, the functionality of compartments can be tuned to facilitate non-native applications, such as artificial nanoreactors for catalysis. In this review, we analyze how protein structure determines the porosity and impacts the function of both native and engineered compartments, highlighting the wealth of structural data recently obtained by cryo-EM and X-ray crystallography. Through this analysis, we offer perspectives on how current structural insights can inform future studies into the design of artificial protein compartments as nanoreactors with tunable porosity and function.
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Affiliation(s)
- Nuren Tasneem
- School of Chemistry, The University of Sydney, Eastern Avenue, Camperdown, New South Wales 2006, Australia
| | - Taylor N Szyszka
- School of Chemistry, The University of Sydney, Eastern Avenue, Camperdown, New South Wales 2006, Australia
- University of Sydney Nano Institute, Camperdown, New South Wales 2006, Australia
| | - Eric N Jenner
- School of Chemistry, The University of Sydney, Eastern Avenue, Camperdown, New South Wales 2006, Australia
| | - Yu Heng Lau
- School of Chemistry, The University of Sydney, Eastern Avenue, Camperdown, New South Wales 2006, Australia
- University of Sydney Nano Institute, Camperdown, New South Wales 2006, Australia
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23
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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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