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Gu Y, Guberman-Pfeffer MJ, Srikanth V, Shen C, Giska F, Gupta K, Londer Y, Samatey FA, Batista VS, Malvankar NS. Author Correction: Structure of Geobacter cytochrome OmcZ identifies mechanism of nanowire assembly and conductivity. Nat Microbiol 2024:10.1038/s41564-024-01702-0. [PMID: 38684912 DOI: 10.1038/s41564-024-01702-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/02/2024]
Affiliation(s)
- Yangqi Gu
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
- PNAC division, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
| | - Matthew J Guberman-Pfeffer
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Vishok Srikanth
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Cong Shen
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Microbiology, Yale University, New Haven, CT, USA
| | - Fabian Giska
- Department of Cell Biology, Yale University, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
| | - Kallol Gupta
- Department of Cell Biology, Yale University, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
| | - Yuri Londer
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Fadel A Samatey
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | | | - Nikhil S Malvankar
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
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Portela PC, Shipps CC, Shen C, Srikanth V, Salgueiro CA, Malvankar NS. Widespread extracellular electron transfer pathways for charging microbial cytochrome OmcS nanowires via periplasmic cytochromes PpcABCDE. Nat Commun 2024; 15:2434. [PMID: 38509081 PMCID: PMC10954620 DOI: 10.1038/s41467-024-46192-0] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/04/2023] [Accepted: 02/19/2024] [Indexed: 03/22/2024] Open
Abstract
Extracellular electron transfer (EET) via microbial nanowires drives globally-important environmental processes and biotechnological applications for bioenergy, bioremediation, and bioelectronics. Due to highly-redundant and complex EET pathways, it is unclear how microbes wire electrons rapidly (>106 s-1) from the inner-membrane through outer-surface nanowires directly to an external environment despite a crowded periplasm and slow (<105 s-1) electron diffusion among periplasmic cytochromes. Here, we show that Geobacter sulfurreducens periplasmic cytochromes PpcABCDE inject electrons directly into OmcS nanowires by binding transiently with differing efficiencies, with the least-abundant cytochrome (PpcC) showing the highest efficiency. Remarkably, this defined nanowire-charging pathway is evolutionarily conserved in phylogenetically-diverse bacteria capable of EET. OmcS heme reduction potentials are within 200 mV of each other, with a midpoint 82 mV-higher than reported previously. This could explain efficient EET over micrometres at ultrafast (<200 fs) rates with negligible energy loss. Engineering this minimal nanowire-charging pathway may yield microbial chassis with improved performance.
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Affiliation(s)
- Pilar C Portela
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
- UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal
| | - Catharine C Shipps
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Cong Shen
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Vishok Srikanth
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Carlos A Salgueiro
- Associate Laboratory i4HB - Institute for Health and Bioeconomy, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal.
- UCIBIO - Applied Molecular Biosciences Unit, Department of Chemistry, NOVA School of Science and Technology, Universidade NOVA de Lisboa, Caparica, Portugal.
| | - Nikhil S Malvankar
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
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3
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Potapova A, Garvey W, Dahl P, Guo S, Chang Y, Schwechheimer C, Trebino MA, Floyd KA, Phinney BS, Liu J, Malvankar NS, Yildiz FH. Outer membrane vesicles and the outer membrane protein OmpU govern Vibrio cholerae biofilm matrix assembly. mBio 2024; 15:e0330423. [PMID: 38206049 PMCID: PMC10865864 DOI: 10.1128/mbio.03304-23] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/07/2023] [Accepted: 12/12/2023] [Indexed: 01/12/2024] Open
Abstract
Biofilms are matrix-encased microbial communities that increase the environmental fitness and infectivity of many human pathogens including Vibrio cholerae. Biofilm matrix assembly is essential for biofilm formation and function. Known components of the V. cholerae biofilm matrix are the polysaccharide Vibrio polysaccharide (VPS), matrix proteins RbmA, RbmC, Bap1, and extracellular DNA, but the majority of the protein composition is uncharacterized. This study comprehensively analyzed the biofilm matrix proteome and revealed the presence of outer membrane proteins (OMPs). Outer membrane vesicles (OMVs) were also present in the V. cholerae biofilm matrix and were associated with OMPs and many biofilm matrix proteins suggesting that they participate in biofilm matrix assembly. Consistent with this, OMVs had the capability to alter biofilm structural properties depending on their composition. OmpU was the most prevalent OMP in the matrix, and its absence altered biofilm architecture by increasing VPS production. Single-cell force spectroscopy revealed that proteins critical for biofilm formation, OmpU, the matrix proteins RbmA, RbmC, Bap1, and VPS contribute to cell-surface adhesion forces at differing efficiency, with VPS showing the highest efficiency whereas Bap1 showing the lowest efficiency. Our findings provide new insights into the molecular mechanisms underlying biofilm matrix assembly in V. cholerae, which may provide new opportunities to develop inhibitors that specifically alter biofilm matrix properties and, thus, affect either the environmental survival or pathogenesis of V. cholerae.IMPORTANCECholera remains a major public health concern. Vibrio cholerae, the causative agent of cholera, forms biofilms, which are critical for its transmission, infectivity, and environmental persistence. While we know that the V. cholerae biofilm matrix contains exopolysaccharide, matrix proteins, and extracellular DNA, we do not have a comprehensive understanding of the majority of biofilm matrix components. Here, we discover outer membrane vesicles (OMVs) within the biofilm matrix of V. cholerae. Proteomic analysis of the matrix and matrix-associated OMVs showed that OMVs carry key matrix proteins and Vibrio polysaccharide (VPS) to help build biofilms. We also characterize the role of the highly abundant outer membrane protein OmpU in biofilm formation and show that it impacts biofilm architecture in a VPS-dependent manner. Understanding V. cholerae biofilm formation is important for developing a better prevention and treatment strategy framework.
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Affiliation(s)
- Anna Potapova
- Department of Microbiology and Environmental Toxicology, University of California-Santa Cruz, Santa Cruz, California, USA
| | - William Garvey
- Department of Microbiology and Environmental Toxicology, University of California-Santa Cruz, Santa Cruz, California, USA
| | - Peter Dahl
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
- Microbial Sciences Institute, Yale University, West Haven, Connecticut, USA
| | - Shuaiqi Guo
- Microbial Sciences Institute, Yale University, West Haven, Connecticut, USA
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, Connecticut, USA
| | - Yunjie Chang
- Microbial Sciences Institute, Yale University, West Haven, Connecticut, USA
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, Connecticut, USA
| | - Carmen Schwechheimer
- Department of Microbiology and Environmental Toxicology, University of California-Santa Cruz, Santa Cruz, California, USA
| | - Michael A. Trebino
- Department of Microbiology and Environmental Toxicology, University of California-Santa Cruz, Santa Cruz, California, USA
| | - Kyle A. Floyd
- Department of Microbiology and Environmental Toxicology, University of California-Santa Cruz, Santa Cruz, California, USA
| | - Brett S. Phinney
- Proteomics Core Facility, UC Davis Genome Center, University of California-Davis, Davis, California, USA
| | - Jun Liu
- Microbial Sciences Institute, Yale University, West Haven, Connecticut, USA
- Department of Microbial Pathogenesis, Yale School of Medicine, New Haven, Connecticut, USA
| | - Nikhil S. Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, USA
- Microbial Sciences Institute, Yale University, West Haven, Connecticut, USA
| | - Fitnat H. Yildiz
- Department of Microbiology and Environmental Toxicology, University of California-Santa Cruz, Santa Cruz, California, USA
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4
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Gu Y, Guberman-Pfeffer MJ, Srikanth V, Shen C, Giska F, Gupta K, Londer Y, Samatey FA, Batista VS, Malvankar NS. Structure of Geobacter cytochrome OmcZ identifies mechanism of nanowire assembly and conductivity. Nat Microbiol 2023; 8:284-298. [PMID: 36732469 PMCID: PMC9999484 DOI: 10.1038/s41564-022-01315-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 12.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/19/2022] [Accepted: 12/20/2022] [Indexed: 02/04/2023]
Abstract
OmcZ nanowires produced by Geobacter species have high electron conductivity (>30 S cm-1). Of 111 cytochromes present in G. sulfurreducens, OmcZ is the only known nanowire-forming cytochrome essential for the formation of high-current-density biofilms that require long-distance (>10 µm) extracellular electron transport. However, the mechanisms underlying OmcZ nanowire assembly and high conductivity are unknown. Here we report a 3.5-Å-resolution cryogenic electron microscopy structure for OmcZ nanowires. Our structure reveals linear and closely stacked haems that may account for conductivity. Surface-exposed haems and charge interactions explain how OmcZ nanowires bind to diverse extracellular electron acceptors and how organization of nanowire network re-arranges in different biochemical environments. In vitro studies explain how G. sulfurreducens employ a serine protease to control the assembly of OmcZ monomers into nanowires. We find that both OmcZ and serine protease are widespread in environmentally important bacteria and archaea, thus establishing a prevalence of nanowire biogenesis across diverse species and environments.
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Affiliation(s)
- Yangqi Gu
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA.
- PNAC division, Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
| | - Matthew J Guberman-Pfeffer
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Vishok Srikanth
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Cong Shen
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Microbiology, Yale University, New Haven, CT, USA
| | - Fabian Giska
- Department of Cell Biology, Yale University, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
| | - Kallol Gupta
- Department of Cell Biology, Yale University, New Haven, CT, USA
- Nanobiology Institute, Yale University, West Haven, CT, USA
| | - Yuri Londer
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Fadel A Samatey
- Microbial Sciences Institute, Yale University, West Haven, CT, USA
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | | | - Nikhil S Malvankar
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.
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5
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Xing H, Huang Y, Kunkemoeller BH, Dahl PJ, Muraleetharan O, Malvankar NS, Murrell MP, Kyriakides TR. Dysregulation of TSP2-Rac1-WAVE2 axis in diabetic cells leads to cytoskeletal disorganization, increased cell stiffness, and dysfunction. Sci Rep 2022; 12:22474. [PMID: 36577792 PMCID: PMC9797577 DOI: 10.1038/s41598-022-26337-1] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/26/2022] [Accepted: 12/13/2022] [Indexed: 12/29/2022] Open
Abstract
Fibroblasts are a major cell population that perform critical functions in the wound healing process. In response to injury, they proliferate and migrate into the wound space, engaging in extracellular matrix (ECM) production, remodeling, and contraction. However, there is limited knowledge of how fibroblast functions are altered in diabetes. To address this gap, several state-of-the-art microscopy techniques were employed to investigate morphology, migration, ECM production, 2D traction, 3D contraction, and cell stiffness. Analysis of cell-derived matrix (CDM) revealed that diabetic fibroblasts produce thickened and less porous ECM that hindered migration of normal fibroblasts. In addition, diabetic fibroblasts were found to lose spindle-like shape, migrate slower, generate less traction force, exert limited 3D contractility, and have increased cell stiffness. These changes were due, in part, to a decreased level of active Rac1 and a lack of co-localization between F-actin and Waskott-Aldrich syndrome protein family verprolin homologous protein 2 (WAVE2). Interestingly, deletion of thrombospondin-2 (TSP2) in diabetic fibroblasts rescued these phenotypes and restored normal levels of active Rac1 and WAVE2-F-actin co-localization. These results provide a comprehensive view of the extent of diabetic fibroblast dysfunction, highlighting the regulatory role of the TSP2-Rac1-WAVE2-actin axis, and describing a new function of TSP2 in regulating cytoskeleton organization.
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Affiliation(s)
- Hao Xing
- Department of Biomedical Engineering, Yale University, New Haven, USA.,Vascular Biology and Therapeutics Program, Yale University, New Haven, USA
| | - Yaqing Huang
- Department of Pathology, Yale University, New Haven, USA.,Vascular Biology and Therapeutics Program, Yale University, New Haven, USA
| | - Britta H Kunkemoeller
- Department of Pathology, Yale University, New Haven, USA.,Vascular Biology and Therapeutics Program, Yale University, New Haven, USA
| | - Peter J Dahl
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, USA.,Microbial Sciences Institute, Yale University, New Haven, USA
| | | | - Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, USA.,Microbial Sciences Institute, Yale University, New Haven, USA
| | - Michael P Murrell
- Department of Biomedical Engineering, Yale University, New Haven, USA.,Department of Physics, Yale University, New Haven, USA.,Systems Biology Institute, Yale University, New Haven, USA
| | - Themis R Kyriakides
- Department of Biomedical Engineering, Yale University, New Haven, USA. .,Department of Pathology, Yale University, New Haven, USA. .,Vascular Biology and Therapeutics Program, Yale University, New Haven, USA.
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6
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Neu J, Shipps CC, Guberman-Pfeffer MJ, Shen C, Srikanth V, Spies JA, Kirchhofer ND, Yalcin SE, Brudvig GW, Batista VS, Malvankar NS. Microbial biofilms as living photoconductors due to ultrafast electron transfer in cytochrome OmcS nanowires. Nat Commun 2022; 13:5150. [PMID: 36071037 PMCID: PMC9452534 DOI: 10.1038/s41467-022-32659-5] [Citation(s) in RCA: 12] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Accepted: 08/09/2022] [Indexed: 11/09/2022] Open
Abstract
Light-induced microbial electron transfer has potential for efficient production of value-added chemicals, biofuels and biodegradable materials owing to diversified metabolic pathways. However, most microbes lack photoactive proteins and require synthetic photosensitizers that suffer from photocorrosion, photodegradation, cytotoxicity, and generation of photoexcited radicals that are harmful to cells, thus severely limiting the catalytic performance. Therefore, there is a pressing need for biocompatible photoconductive materials for efficient electronic interface between microbes and electrodes. Here we show that living biofilms of Geobacter sulfurreducens use nanowires of cytochrome OmcS as intrinsic photoconductors. Photoconductive atomic force microscopy shows up to 100-fold increase in photocurrent in purified individual nanowires. Photocurrents respond rapidly (<100 ms) to the excitation and persist reversibly for hours. Femtosecond transient absorption spectroscopy and quantum dynamics simulations reveal ultrafast (~200 fs) electron transfer between nanowire hemes upon photoexcitation, enhancing carrier density and mobility. Our work reveals a new class of natural photoconductors for whole-cell catalysis. Despite enormous potential of solar-driven biocatalysis, most living systems lack photoactive proteins and require toxic and expensive synthetic materials limiting the performance. Here, a class of natural photoconductors is demonstrated through sub-picosecond heme-to-heme electron transfer in bacteria-produced protein nanowires.
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Affiliation(s)
- Jens Neu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA. .,Microbial Sciences Institute, Yale University, West Haven, CT, USA.
| | - Catharine C Shipps
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Matthew J Guberman-Pfeffer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Cong Shen
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Vishok Srikanth
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Jacob A Spies
- Department of Chemistry, Yale University, New Haven, CT, USA
| | | | - Sibel Ebru Yalcin
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, USA
| | - Gary W Brudvig
- Department of Chemistry, Yale University, New Haven, CT, USA
| | | | - Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA. .,Microbial Sciences Institute, Yale University, West Haven, CT, USA.
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7
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Dahl PJ, Yi SM, Gu Y, Acharya A, Shipps C, Neu J, O’Brien JP, Morzan UN, Chaudhuri S, Guberman-Pfeffer MJ, Vu D, Yalcin SE, Batista VS, Malvankar NS. A 300-fold conductivity increase in microbial cytochrome nanowires due to temperature-induced restructuring of hydrogen bonding networks. Sci Adv 2022; 8:eabm7193. [PMID: 35544567 PMCID: PMC9094664 DOI: 10.1126/sciadv.abm7193] [Citation(s) in RCA: 21] [Impact Index Per Article: 10.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/06/2021] [Accepted: 03/28/2022] [Indexed: 06/10/2023]
Abstract
Although proteins are considered as nonconductors that transfer electrons only up to 1 to 2 nanometers via tunneling, Geobacter sulfurreducens transports respiratory electrons over micrometers, to insoluble acceptors or syntrophic partner cells, via nanowires composed of polymerized cytochrome OmcS. However, the mechanism enabling this long-range conduction is unclear. Here, we demonstrate that individual nanowires exhibit theoretically predicted hopping conductance, at rate (>1010 s-1) comparable to synthetic molecular wires, with negligible carrier loss over micrometers. Unexpectedly, nanowires show a 300-fold increase in their intrinsic conductance upon cooling, which vanishes upon deuteration. Computations show that cooling causes a massive rearrangement of hydrogen bonding networks in nanowires. Cooling makes hemes more planar, as revealed by Raman spectroscopy and simulations, and lowers their reduction potential. We find that the protein surrounding the hemes acts as a temperature-sensitive switch that controls charge transport by sensing environmental perturbations. Rational engineering of heme environments could enable systematic tuning of extracellular respiration.
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Affiliation(s)
- Peter J. Dahl
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
| | - Sophia M. Yi
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
| | - Yangqi Gu
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, CT, USA
| | - Atanu Acharya
- Department of Chemistry, Yale University, New Haven, CT, USA
| | - Catharine Shipps
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
| | - Jens Neu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
| | - J. Patrick O’Brien
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
| | - Uriel N. Morzan
- Department of Chemistry, Yale University, New Haven, CT, USA
| | | | - Matthew J. Guberman-Pfeffer
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
| | - Dennis Vu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
| | - Sibel Ebru Yalcin
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
| | | | - Nikhil S. Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
- Microbial Sciences Institute, Yale University, New Haven, CT, USA
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8
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Duy PQ, Weise SC, Marini C, Li XJ, Liang D, Dahl PJ, Ma S, Spajic A, Dong W, Juusola J, Kiziltug E, Kundishora AJ, Koundal S, Pedram MZ, Torres-Fernández LA, Händler K, De Domenico E, Becker M, Ulas T, Juranek SA, Cuevas E, Hao LT, Jux B, Sousa AMM, Liu F, Kim SK, Li M, Yang Y, Takeo Y, Duque A, Nelson-Williams C, Ha Y, Selvaganesan K, Robert SM, Singh AK, Allington G, Furey CG, Timberlake AT, Reeves BC, Smith H, Dunbar A, DeSpenza T, Goto J, Marlier A, Moreno-De-Luca A, Yu X, Butler WE, Carter BS, Lake EMR, Constable RT, Rakic P, Lin H, Deniz E, Benveniste H, Malvankar NS, Estrada-Veras JI, Walsh CA, Alper SL, Schultze JL, Paeschke K, Doetzlhofer A, Wulczyn FG, Jin SC, Lifton RP, Sestan N, Kolanus W, Kahle KT. Impaired neurogenesis alters brain biomechanics in a neuroprogenitor-based genetic subtype of congenital hydrocephalus. Nat Neurosci 2022; 25:458-473. [PMID: 35379995 PMCID: PMC9664907 DOI: 10.1038/s41593-022-01043-3] [Citation(s) in RCA: 33] [Impact Index Per Article: 16.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2021] [Accepted: 02/28/2022] [Indexed: 01/16/2023]
Abstract
Hydrocephalus, characterized by cerebral ventricular dilatation, is routinely attributed to primary defects in cerebrospinal fluid (CSF) homeostasis. This fosters CSF shunting as the leading reason for brain surgery in children despite considerable disease heterogeneity. In this study, by integrating human brain transcriptomics with whole-exome sequencing of 483 patients with congenital hydrocephalus (CH), we found convergence of CH risk genes in embryonic neuroepithelial stem cells. Of all CH risk genes, TRIM71/lin-41 harbors the most de novo mutations and is most specifically expressed in neuroepithelial cells. Mice harboring neuroepithelial cell-specific Trim71 deletion or CH-specific Trim71 mutation exhibit prenatal hydrocephalus. CH mutations disrupt TRIM71 binding to its RNA targets, causing premature neuroepithelial cell differentiation and reduced neurogenesis. Cortical hypoplasia leads to a hypercompliant cortex and secondary ventricular enlargement without primary defects in CSF circulation. These data highlight the importance of precisely regulated neuroepithelial cell fate for normal brain-CSF biomechanics and support a clinically relevant neuroprogenitor-based paradigm of CH.
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Affiliation(s)
- Phan Q Duy
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA.,Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA.,Medical Scientist Training Program, Yale University School of Medicine, New Haven, CT, USA
| | - Stefan C Weise
- Molecular Immunology and Cell Biology, Life & Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Claudia Marini
- Institute for Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Xiao-Jun Li
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Center for Hearing and Balance, Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - Dan Liang
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Peter J Dahl
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Shaojie Ma
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Ana Spajic
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Weilai Dong
- Laboratory of Human Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | | | - Emre Kiziltug
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Adam J Kundishora
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Sunil Koundal
- Department of Anesthesiology, Yale University School of Medicine, New Haven, CT, USA
| | - Maysam Z Pedram
- Department of Anesthesiology, Yale University School of Medicine, New Haven, CT, USA
| | - Lucia A Torres-Fernández
- Molecular Immunology and Cell Biology, Life & Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Kristian Händler
- Systems Medicine, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Bonn, Germany.,Genomics and Immunoregulation, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany.,Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE). PRECISE Platform for Genomics and Epigenomics at DZNE and University of Bonn, Bonn, Germany
| | - Elena De Domenico
- Systems Medicine, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Bonn, Germany.,Genomics and Immunoregulation, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany.,Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE). PRECISE Platform for Genomics and Epigenomics at DZNE and University of Bonn, Bonn, Germany
| | - Matthias Becker
- Systems Medicine, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Bonn, Germany.,Genomics and Immunoregulation, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany.,Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE). PRECISE Platform for Genomics and Epigenomics at DZNE and University of Bonn, Bonn, Germany
| | - Thomas Ulas
- Systems Medicine, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Bonn, Germany.,Genomics and Immunoregulation, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany.,Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE). PRECISE Platform for Genomics and Epigenomics at DZNE and University of Bonn, Bonn, Germany
| | - Stefan A Juranek
- Department of Oncology, Hematology and Rheumatology, University Hospital Bonn, Bonn, Germany
| | - Elisa Cuevas
- Stem Cells and Regenerative Medicine Section, University College London Great Ormond Street Institute of Child Health, London, UK
| | - Le Thi Hao
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Bettina Jux
- Molecular Immunology and Cell Biology, Life & Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - André M M Sousa
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Fuchen Liu
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Suel-Kee Kim
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Mingfeng Li
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Yiying Yang
- Yale Stem Cell Center, Yale University School of Medicine, New Haven, CT, USA
| | - Yutaka Takeo
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Alvaro Duque
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | | | - Yonghyun Ha
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Kartiga Selvaganesan
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Stephanie M Robert
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Amrita K Singh
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Garrett Allington
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Charuta G Furey
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Andrew T Timberlake
- Department of Genetics, Yale University School of Medicine, New Haven, CT, USA
| | - Benjamin C Reeves
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Hannah Smith
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Ashley Dunbar
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Tyrone DeSpenza
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - June Goto
- Division of Pediatric Neurosurgery, Cincinnati Children's Hospital Medical Center, Cincinnati, OH, USA
| | - Arnaud Marlier
- Department of Neurosurgery, Yale University School of Medicine, New Haven, CT, USA
| | - Andres Moreno-De-Luca
- Department of Radiology, Autism & Developmental Medicine Institute, Genomic Medicine Institute, Geisinger, Danville, PA, USA
| | - Xin Yu
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - William E Butler
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Bob S Carter
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA
| | - Evelyn M R Lake
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - R Todd Constable
- Department of Radiology and Biomedical Imaging, Yale University School of Medicine, New Haven, CT, USA
| | - Pasko Rakic
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Haifan Lin
- Yale Stem Cell Center, Yale University School of Medicine, New Haven, CT, USA
| | - Engin Deniz
- Department of Pediatrics, Yale University School of Medicine, New Haven, CT, USA
| | - Helene Benveniste
- Department of Anesthesiology, Yale University School of Medicine, New Haven, CT, USA
| | - Nikhil S Malvankar
- Microbial Sciences Institute, Yale University, West Haven, CT, USA.,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, USA
| | - Juvianee I Estrada-Veras
- Henry M. Jackson Foundation for the Advancement of Military Medicine, Bethesda, MD, USA.,Pediatric Subspecialty Genetics Walter Reed National Military Medical Center, Bethesda, MD, USA.,Murtha Cancer Center/Research Program, Department of Surgery, Uniformed Services University of the Health Sciences, Bethesda, MD, USA
| | - Christopher A Walsh
- Division of Genetics and Genomics, Manton Center for Orphan Disease Research, Department of Pediatrics, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA.,Departments of Pediatrics and Neurology, Harvard Medical School, Boston, MA, USA.,Broad Institute of MIT and Harvard, Cambridge, MA, USA
| | - Seth L Alper
- Broad Institute of MIT and Harvard, Cambridge, MA, USA.,Division of Nephrology and Vascular Biology Research Center, Beth Israel Deaconess Medical Center and Department of Medicine, Harvard Medical School, Boston, MA, USA
| | - Joachim L Schultze
- Systems Medicine, Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE), Bonn, Germany.,Genomics and Immunoregulation, Life & Medical Sciences (LIMES) Institute, University of Bonn, Bonn, Germany.,Deutsches Zentrum für Neurodegenerative Erkrankungen (DZNE). PRECISE Platform for Genomics and Epigenomics at DZNE and University of Bonn, Bonn, Germany
| | - Katrin Paeschke
- Department of Oncology, Hematology and Rheumatology, University Hospital Bonn, Bonn, Germany
| | - Angelika Doetzlhofer
- Solomon H. Snyder Department of Neuroscience, Johns Hopkins University School of Medicine, Baltimore, MD, USA.,Center for Hearing and Balance, Department of Otolaryngology-Head and Neck Surgery, Johns Hopkins University School of Medicine, Baltimore, MD, USA
| | - F Gregory Wulczyn
- Institute for Cell Biology and Neurobiology, Charité-Universitätsmedizin Berlin, Corporate Member of Freie Universität Berlin, Humboldt-Universität zu Berlin, and Berlin Institute of Health, Berlin, Germany
| | - Sheng Chih Jin
- Department of Genetics, Washington University School of Medicine, St. Louis, MO, USA
| | - Richard P Lifton
- Laboratory of Human Genetics and Genomics, The Rockefeller University, New York, NY, USA
| | - Nenad Sestan
- Department of Neuroscience and Kavli Institute for Neuroscience, Yale University School of Medicine, New Haven, CT, USA
| | - Waldemar Kolanus
- Molecular Immunology and Cell Biology, Life & Medical Sciences Institute (LIMES), University of Bonn, Bonn, Germany
| | - Kristopher T Kahle
- Department of Neurosurgery, Massachusetts General Hospital, Harvard Medical School, Boston, MA, USA. .,Division of Genetics and Genomics, Manton Center for Orphan Disease Research, Department of Pediatrics, and Howard Hughes Medical Institute, Boston Children's Hospital, Boston, MA, USA. .,Broad Institute of MIT and Harvard, Cambridge, MA, USA. .,Harvard Center for Hydrocephalus and Neurodevelopmental Disorders, Massachusetts General Hospital, Boston, MA, USA.
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9
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Shapiro DM, Mandava G, Yalcin SE, Arranz-Gibert P, Dahl PJ, Shipps C, Gu Y, Srikanth V, Salazar-Morales AI, O'Brien JP, Vanderschuren K, Vu D, Batista VS, Malvankar NS, Isaacs FJ. Protein nanowires with tunable functionality and programmable self-assembly using sequence-controlled synthesis. Nat Commun 2022; 13:829. [PMID: 35149672 PMCID: PMC8837800 DOI: 10.1038/s41467-022-28206-x] [Citation(s) in RCA: 19] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2021] [Accepted: 01/13/2022] [Indexed: 12/17/2022] Open
Abstract
Advances in synthetic biology permit the genetic encoding of synthetic chemistries at monomeric precision, enabling the synthesis of programmable proteins with tunable properties. Bacterial pili serve as an attractive biomaterial for the development of engineered protein materials due to their ability to self-assemble into mechanically robust filaments. However, most biomaterials lack electronic functionality and atomic structures of putative conductive proteins are not known. Here, we engineer high electronic conductivity in pili produced by a genomically-recoded E. coli strain. Incorporation of tryptophan into pili increased conductivity of individual filaments >80-fold. Computationally-guided ordering of the pili into nanostructures increased conductivity 5-fold compared to unordered pili networks. Site-specific conjugation of pili with gold nanoparticles, facilitated by incorporating the nonstandard amino acid propargyloxy-phenylalanine, increased filament conductivity ~170-fold. This work demonstrates the sequence-defined production of highly-conductive protein nanowires and hybrid organic-inorganic biomaterials with genetically-programmable electronic functionalities not accessible in nature or through chemical-based synthesis. Bacterial hairs called pili become highly-conductive electric wires upon addition of both natural and synthetic amino acids conjugated with gold nanoparticles. Here the authors use computationally-guided ordering further increasing their conductivity, thus yielding genetically-programmable materials.
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Affiliation(s)
- Daniel Mark Shapiro
- Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT, 06520, USA.,Systems Biology Institute, Yale University, West Haven, CT, 06516, USA.,Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Gunasheil Mandava
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Sibel Ebru Yalcin
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Pol Arranz-Gibert
- Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT, 06520, USA.,Systems Biology Institute, Yale University, West Haven, CT, 06516, USA
| | - Peter J Dahl
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Catharine Shipps
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Yangqi Gu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Vishok Srikanth
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Aldo I Salazar-Morales
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - J Patrick O'Brien
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Koen Vanderschuren
- Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT, 06520, USA.,Systems Biology Institute, Yale University, West Haven, CT, 06516, USA
| | - Dennis Vu
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA.,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA
| | - Victor S Batista
- Department of Chemistry, Yale University, New Haven, CT, 06520, USA
| | - Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06520, USA. .,Microbial Sciences Institute, Yale University, West Haven, CT, 06516, USA.
| | - Farren J Isaacs
- Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT, 06520, USA. .,Systems Biology Institute, Yale University, West Haven, CT, 06516, USA. .,Department of Biomedical Engineering, Yale University, New Haven, CT, 06520, USA.
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10
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Wong GCL, Antani JD, Lele PP, Chen J, Nan B, Kühn MJ, Persat A, Bru JL, Høyland-Kroghsbo NM, Siryaporn A, Conrad JC, Carrara F, Yawata Y, Stocker R, V Brun Y, Whitfield GB, Lee CK, de Anda J, Schmidt WC, Golestanian R, O'Toole GA, Floyd KA, Yildiz FH, Yang S, Jin F, Toyofuku M, Eberl L, Nomura N, Zacharoff LA, El-Naggar MY, Yalcin SE, Malvankar NS, Rojas-Andrade MD, Hochbaum AI, Yan J, Stone HA, Wingreen NS, Bassler BL, Wu Y, Xu H, Drescher K, Dunkel J. Roadmap on emerging concepts in the physical biology of bacterial biofilms: from surface sensing to community formation. Phys Biol 2021; 18. [PMID: 33462162 PMCID: PMC8506656 DOI: 10.1088/1478-3975/abdc0e] [Citation(s) in RCA: 28] [Impact Index Per Article: 9.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/05/2020] [Accepted: 01/14/2021] [Indexed: 11/29/2022]
Abstract
Bacterial biofilms are communities of bacteria that exist as aggregates that can adhere to surfaces or be free-standing. This complex, social mode of cellular organization is fundamental to the physiology of microbes and often exhibits surprising behavior. Bacterial biofilms are more than the sum of their parts: single-cell behavior has a complex relation to collective community behavior, in a manner perhaps cognate to the complex relation between atomic physics and condensed matter physics. Biofilm microbiology is a relatively young field by biology standards, but it has already attracted intense attention from physicists. Sometimes, this attention takes the form of seeing biofilms as inspiration for new physics. In this roadmap, we highlight the work of those who have taken the opposite strategy: we highlight the work of physicists and physical scientists who use physics to engage fundamental concepts in bacterial biofilm microbiology, including adhesion, sensing, motility, signaling, memory, energy flow, community formation and cooperativity. These contributions are juxtaposed with microbiologists who have made recent important discoveries on bacterial biofilms using state-of-the-art physical methods. The contributions to this roadmap exemplify how well physics and biology can be combined to achieve a new synthesis, rather than just a division of labor.
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Affiliation(s)
- Gerard C L Wong
- Department of Bioengineering, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America.,Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America.,California NanoSystems Institute, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America
| | - Jyot D Antani
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, United States of America
| | - Pushkar P Lele
- Artie McFerrin Department of Chemical Engineering, Texas A&M University, College Station, TX 77843, United States of America
| | - Jing Chen
- Department of Biological Sciences, Virginia Polytechnic Institute and State University, Blacksburg, VA24061, United States of America
| | - Beiyan Nan
- Department of Biology, Texas A&M University, College Station, Texas, TX 77845, United States of America
| | - Marco J Kühn
- Institute of Bioengineering and Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Alexandre Persat
- Institute of Bioengineering and Global Health Institute, School of Life Sciences, École Polytechnique Fédérale de Lausanne, Lausanne, Switzerland
| | - Jean-Louis Bru
- Department of Molecular Biology & Biochemistry, University of California-Irvine, California, CA 92697, United States of America
| | | | - Albert Siryaporn
- Department of Molecular Biology & Biochemistry, University of California-Irvine, California, CA 92697, United States of America.,Department of Physics & Astronomy, University of California-Irvine, California, CA 92697, United States of America
| | - Jacinta C Conrad
- William A Brookshire Department of Chemical and Biomolecular Engineering, University of Houston, Houston, Texas, TX 77204, United States of America
| | - Francesco Carrara
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, 8093 Zurich, Switzerland
| | - Yutaka Yawata
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.,Microbiology Research Center for Sustainability, University of Tsukuba, 305-8572 Tsukuba, Japan
| | - Roman Stocker
- Institute of Environmental Engineering, Department of Civil, Environmental and Geomatic Engineering, ETH Zurich, 8093 Zurich, Switzerland
| | - Yves V Brun
- University of Montreal, Faculty of Medicine, Montreal, Quebec, H3C 3J7, Canada
| | - Gregory B Whitfield
- University of Montreal, Faculty of Medicine, Montreal, Quebec, H3C 3J7, Canada
| | - Calvin K Lee
- Department of Bioengineering, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America.,Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America.,California NanoSystems Institute, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America
| | - Jaime de Anda
- Department of Bioengineering, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America.,Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America.,California NanoSystems Institute, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America
| | - William C Schmidt
- Department of Bioengineering, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America.,Department of Chemistry and Biochemistry, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America.,California NanoSystems Institute, University of California-Los Angeles, Los Angeles, California, CA 90095, United States of America
| | - Ramin Golestanian
- Max Planck Institute for Dynamics and Self-Organization (MPIDS), D-37077 Göttingen, Germany.,Rudolf Peierls Centre for Theoretical Physics, University of Oxford, Oxford OX1 3PU, United Kingdom
| | - George A O'Toole
- Department of Microbiology and Immunology, Geisel School of Medicine at Dartmouth, Hanover, NH 03755, United States of America
| | - Kyle A Floyd
- Department of Microbiology and Environmental Toxicology, University of California-Santa Cruz, Santa Cruz, California, CA 95060, United States of America
| | - Fitnat H Yildiz
- Department of Microbiology and Environmental Toxicology, University of California-Santa Cruz, Santa Cruz, California, CA 95060, United States of America
| | - Shuai Yang
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China
| | - Fan Jin
- CAS Key Laboratory of Quantitative Engineering Biology, Shenzhen Institute of Synthetic Biology, Shenzhen Institutes of Advanced Technology, Chinese Academy of Sciences, Shenzhen 518055, People's Republic of China
| | - Masanori Toyofuku
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.,Microbiology Research Center for Sustainability, University of Tsukuba, 305-8572 Tsukuba, Japan
| | - Leo Eberl
- Department of Plant and Microbial Biology, University of Zürich, 8008 Zürich, Switzerland
| | - Nobuhiko Nomura
- Faculty of Life and Environmental Sciences, University of Tsukuba, Tsukuba, Ibaraki 305-8572, Japan.,Microbiology Research Center for Sustainability, University of Tsukuba, 305-8572 Tsukuba, Japan
| | - Lori A Zacharoff
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, CA 90089, United States of America.,Department of Chemistry, University of Southern California, Los Angeles, California, CA 90089, United States of America
| | - Mohamed Y El-Naggar
- Department of Physics and Astronomy, University of Southern California, Los Angeles, California, CA 90089, United States of America.,Department of Chemistry, University of Southern California, Los Angeles, California, CA 90089, United States of America.,Department of Biological Sciences, University of Southern California, Los Angeles, California, CA 90089, United States of America
| | - Sibel Ebru Yalcin
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, CT 06516, United States of America.,Microbial Sciences Institute, Yale University, New Haven, Connecticut, CT 06516, United States of America
| | - Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, Connecticut, CT 06516, United States of America.,Microbial Sciences Institute, Yale University, New Haven, Connecticut, CT 06516, United States of America
| | - Mauricio D Rojas-Andrade
- Department of Materials Science and Engineering, University of California-Irvine, Irvine, California CA 92697, United States of America
| | - Allon I Hochbaum
- Department of Molecular Biology & Biochemistry, University of California-Irvine, California, CA 92697, United States of America.,Department of Materials Science and Engineering, University of California-Irvine, Irvine, California CA 92697, United States of America.,Department of Chemistry, University of California-Irvine, Irvine, California, CA 92697, United States of America.,Department of Chemical and Biomolecular Engineering, University of California-Irvine, Irvine, California, CA 92697, United States of America
| | - Jing Yan
- Department of Molecular, Cellular and Developmental Biology, Yale University, New Haven, Connecticut, CT 06511, United States of America
| | - Howard A Stone
- Department of Mechanical and Aerospace Engineering, Princeton University, Princeton, New Jersey, NJ 08544, United States of America
| | - Ned S Wingreen
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, NJ 08544, United States of America.,Lewis-Sigler Institute for Integrative Genomics, Princeton University, Princeton, New Jersey, NJ 08544, United States of America
| | - Bonnie L Bassler
- Department of Molecular Biology, Princeton University, Princeton, New Jersey, NJ 08544, United States of America.,The Howard Hughes Medical Institute, Chevy Chase, Maryland MD 20815, United States of America
| | - Yilin Wu
- Department of Physics and Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, People's Republic of China
| | - Haoran Xu
- Department of Physics and Shenzhen Research Institute, The Chinese University of Hong Kong, Shatin, New Territories, Hong Kong, People's Republic of China
| | - Knut Drescher
- Max Planck Institute for Terrestrial Microbiology, 35043 Marburg, Germany.,Department of Physics, Philipps-Universität Marburg, 35043 Marburg, Germany
| | - Jörn Dunkel
- Department of Mathematics, Massachusetts Institute of Technology, Cambridge, Massachusetts, MA 02139-4307, United States of America
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11
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Yalcin SE, Malvankar NS. The blind men and the filament: Understanding structures and functions of microbial nanowires. Curr Opin Chem Biol 2020; 59:193-201. [PMID: 33070100 PMCID: PMC7736336 DOI: 10.1016/j.cbpa.2020.08.004] [Citation(s) in RCA: 44] [Impact Index Per Article: 11.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/31/2020] [Accepted: 08/20/2020] [Indexed: 12/18/2022]
Abstract
Extracellular electron transfer via filamentous protein appendages called 'microbial nanowires' has long been studied in Geobacter and other bacteria because of their crucial role in globally-important environmental processes and their applications for bioenergy, biofuels, and bioelectronics. Thousands of papers thought these nanowires as pili without direct evidence. Here, we summarize recent discoveries that could help resolve two decades of confounding observations. Using cryo-electron microscopy with multimodal functional imaging and a suite of electrical, biochemical, and physiological studies, we find that rather than pili, nanowires are composed of cytochromes OmcS and OmcZ that transport electrons via seamless stacking of hemes over micrometers. We discuss the physiological need for two different nanowires and their potential applications for sensing, synthesis, and energy production.
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Affiliation(s)
- Sibel Ebru Yalcin
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06510, USA; Microbial Sciences Institute, Yale University, New Haven, CT, 06516, USA.
| | - Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, 06510, USA; Microbial Sciences Institute, Yale University, New Haven, CT, 06516, USA.
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12
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Yalcin SE, Legg BA, Yeşilbaş M, Malvankar NS, Boily JF. Direct observation of anisotropic growth of water films on minerals driven by defects and surface tension. Sci Adv 2020; 6:eaaz9708. [PMID: 32832658 PMCID: PMC7439304 DOI: 10.1126/sciadv.aaz9708] [Citation(s) in RCA: 17] [Impact Index Per Article: 4.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/29/2019] [Accepted: 06/10/2020] [Indexed: 05/10/2023]
Abstract
Knowledge of the occurrences of water films on minerals is critical for global biogeochemical and atmospheric processes, including element cycling and ice nucleation. The underlying mechanisms controlling water film growth are, however, misunderstood. Using infrared nanospectroscopy, amplitude-modulated atomic force microscopy, and molecular simulations, we show how water films grow from water vapor on hydrophilic mineral nanoparticles. We imaged films with up to four water layers that grow anisotropically over a single face. Growth usually begins from the near edges of a face where defects preferentially capture water vapor. Thicker films produced by condensation cooling completely engulf nanoparticles and form thicker menisci over defects. The high surface tension of water smooths film surfaces and produces films of inhomogeneous thickness. Nanoscale topography and film surface energy thereby control anisotropic distributions and thicknesses of water films on hydrophilic mineral nanoparticles.
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Affiliation(s)
- Sibel Ebru Yalcin
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
- Microbial Sciences Institute, Yale University, West Haven, CT 06516, USA
- Corresponding author. (J.-F.B.); (S.E.Y.); (N.S.M.)
| | - Benjamin A. Legg
- Physical Sciences Division, Pacific Northwest National Laboratory, Richland, WA 99352, USA
- Department of Materials Science and Engineering, University of Washington, Seattle, WA 98195, USA
| | - Merve Yeşilbaş
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
| | - Nikhil S. Malvankar
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
- Microbial Sciences Institute, Yale University, West Haven, CT 06516, USA
- Corresponding author. (J.-F.B.); (S.E.Y.); (N.S.M.)
| | - Jean-François Boily
- Department of Chemistry, Umeå University, SE-901 87 Umeå, Sweden
- Corresponding author. (J.-F.B.); (S.E.Y.); (N.S.M.)
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13
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Srikanth V, Gu Y, O'Brien JP, Jain R, Ebru Yalcin S, Yi SM, Samatey FA, Malvankar NS. Probing the Role of Metal Coordination and pH in Assembly and Function of Cytochrome Nanowires. Biophys J 2020. [DOI: 10.1016/j.bpj.2019.11.1872] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/24/2022] Open
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14
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Wang F, Gu Y, O'Brien JP, Yi SM, Yalcin SE, Srikanth V, Shen C, Vu D, Ing NL, Hochbaum AI, Egelman EH, Malvankar NS. Structure of Microbial Nanowires Reveals Stacked Hemes that Transport Electrons over Micrometers. Cell 2020; 177:361-369.e10. [PMID: 30951668 DOI: 10.1016/j.cell.2019.03.029] [Citation(s) in RCA: 246] [Impact Index Per Article: 61.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/14/2019] [Accepted: 03/11/2019] [Indexed: 12/21/2022]
Abstract
Long-range (>10 μm) transport of electrons along networks of Geobacter sulfurreducens protein filaments, known as microbial nanowires, has been invoked to explain a wide range of globally important redox phenomena. These nanowires were previously thought to be type IV pili composed of PilA protein. Here, we report a 3.7 Å resolution cryoelectron microscopy structure, which surprisingly reveals that, rather than PilA, G. sulfurreducens nanowires are assembled by micrometer-long polymerization of the hexaheme cytochrome OmcS, with hemes packed within ∼3.5-6 Å of each other. The inter-subunit interfaces show unique structural elements such as inter-subunit parallel-stacked hemes and axial coordination of heme by histidines from neighboring subunits. Wild-type OmcS filaments show 100-fold greater conductivity than other filaments from a ΔomcS strain, highlighting the importance of OmcS to conductivity in these nanowires. This structure explains the remarkable capacity of soil bacteria to transport electrons to remote electron acceptors for respiration and energy sharing.
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Affiliation(s)
- Fengbin Wang
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Yangqi Gu
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - J Patrick O'Brien
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Sophia M Yi
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Sibel Ebru Yalcin
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Vishok Srikanth
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Cong Shen
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Microbial Pathogenesis, Yale University, New Haven, CT 06511, USA
| | - Dennis Vu
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Nicole L Ing
- Department of Materials Science & Engineering, University of California, Irvine, Irvine, CA 92697, USA
| | - Allon I Hochbaum
- Department of Materials Science & Engineering, University of California, Irvine, Irvine, CA 92697, USA; Department of Chemistry, University of California, Irvine, Irvine, CA 92697, USA.
| | - Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
| | - Nikhil S Malvankar
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA.
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15
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Wang F, Gu Y, O'Brien JP, Yi SM, Yalcin SE, Srikanth V, Shen C, Vu D, Ing NL, Hochbaum AI, Egelman EH, Malvankar NS. Structure of Microbial Nanowires Reveals Stacked Hemes that Transport Electrons over Micrometers. Cell 2019; 177:361-369.e10. [PMID: 30951668 DOI: 10.1016/j.cell.03.029] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/26/2018] [Revised: 01/14/2019] [Accepted: 03/11/2019] [Indexed: 05/22/2023]
Abstract
Long-range (>10 μm) transport of electrons along networks of Geobacter sulfurreducens protein filaments, known as microbial nanowires, has been invoked to explain a wide range of globally important redox phenomena. These nanowires were previously thought to be type IV pili composed of PilA protein. Here, we report a 3.7 Å resolution cryoelectron microscopy structure, which surprisingly reveals that, rather than PilA, G. sulfurreducens nanowires are assembled by micrometer-long polymerization of the hexaheme cytochrome OmcS, with hemes packed within ∼3.5-6 Å of each other. The inter-subunit interfaces show unique structural elements such as inter-subunit parallel-stacked hemes and axial coordination of heme by histidines from neighboring subunits. Wild-type OmcS filaments show 100-fold greater conductivity than other filaments from a ΔomcS strain, highlighting the importance of OmcS to conductivity in these nanowires. This structure explains the remarkable capacity of soil bacteria to transport electrons to remote electron acceptors for respiration and energy sharing.
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Affiliation(s)
- Fengbin Wang
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA
| | - Yangqi Gu
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular, Cellular & Developmental Biology, Yale University, New Haven, CT 06511, USA
| | - J Patrick O'Brien
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Sophia M Yi
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Sibel Ebru Yalcin
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Vishok Srikanth
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Cong Shen
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Microbial Pathogenesis, Yale University, New Haven, CT 06511, USA
| | - Dennis Vu
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA
| | - Nicole L Ing
- Department of Materials Science & Engineering, University of California, Irvine, Irvine, CA 92697, USA
| | - Allon I Hochbaum
- Department of Materials Science & Engineering, University of California, Irvine, Irvine, CA 92697, USA; Department of Chemistry, University of California, Irvine, Irvine, CA 92697, USA.
| | - Edward H Egelman
- Department of Biochemistry and Molecular Genetics, University of Virginia School of Medicine, Charlottesville, VA 22908, USA.
| | - Nikhil S Malvankar
- Microbial Sciences Institute, Yale University, New Haven, CT 06516, USA; Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT 06511, USA.
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16
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O'Brien JP, Malvankar NS. A Simple and Low-Cost Procedure for Growing Geobacter sulfurreducens Cell Cultures and Biofilms in Bioelectrochemical Systems. Curr Protoc Microbiol 2016; 43:A.4K.1-A.4K.27. [PMID: 27858972 PMCID: PMC5726868 DOI: 10.1002/cpmc.20] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Anaerobic microorganisms play a central role in several environmental processes and regulate global biogeochemical cycling of nutrients and minerals. Many anaerobic microorganisms are important for the production of bioenergy and biofuels. However, the major hurdle in studying anaerobic microorganisms in the laboratory is the requirement for sophisticated and expensive gassing stations and glove boxes to create and maintain the anaerobic environment. This appendix presents a simple design for a gassing station that can be used readily by an inexperienced investigator for cultivation of anaerobic microorganisms. In addition, this appendix also details the low-cost assembly of bioelectrochemical systems and outlines a simplified procedure for cultivating and analyzing bacterial cell cultures and biofilms that produce electric current, using Geobacter sulfurreducens as a model organism. © 2016 by John Wiley & Sons, Inc.
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Affiliation(s)
- J Patrick O'Brien
- Department of Molecular Biophysics and Biochemistry, Microbial Sciences Institute, Yale University, West Haven, Connecticut
| | - Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Microbial Sciences Institute, Yale University, West Haven, Connecticut
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17
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Malvankar NS, Rotello VM, Tuominen MT, Lovley DR. Reply to 'Measuring conductivity of living Geobacter sulfurreducens biofilms'. Nat Nanotechnol 2016; 11:913-914. [PMID: 27821844 DOI: 10.1038/nnano.2016.191] [Citation(s) in RCA: 16] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Affiliation(s)
- Nikhil S Malvankar
- Department of Molecular Biophysics and Biochemistry, Microbial Sciences Institute, Yale University, Connecticut 06516, USA
| | - Vincent M Rotello
- Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Mark T Tuominen
- Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Derek R Lovley
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003, USA
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18
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Tan Y, Adhikari RY, Malvankar NS, Pi S, Ward JE, Woodard TL, Nevin KP, Xia Q, Tuominen MT, Lovley DR. Synthetic Biological Protein Nanowires with High Conductivity. Small 2016; 12:4481-4485. [PMID: 27409066 DOI: 10.1002/smll.201601112] [Citation(s) in RCA: 76] [Impact Index Per Article: 9.5] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2016] [Revised: 06/11/2016] [Indexed: 06/06/2023]
Abstract
Genetic modification to add tryptophan to PilA, the monomer for the electrically conductive pili of Geobacter sulfurreducens, yields conductive protein filaments 2000-fold more conductive than the wild-type pili while cutting the diameter in half to 1.5 nm.
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Affiliation(s)
- Yang Tan
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Ramesh Y Adhikari
- Department of Physics, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Nikhil S Malvankar
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
- Department of Physics, University of Massachusetts Amherst, Amherst, MA, 01003, USA
- Department of Molecular Biophysics and Biochemistry, Microbial Sciences Institute, Yale University, New Haven, CT, 06516, USA
| | - Shuang Pi
- Department of Electrical and Computer Engineering, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Joy E Ward
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Trevor L Woodard
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Kelly P Nevin
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Qiangfei Xia
- Department of Electrical and Computer Engineering, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Mark T Tuominen
- Department of Physics, University of Massachusetts Amherst, Amherst, MA, 01003, USA
| | - Derek R Lovley
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, 01003, USA
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19
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Tan Y, Adhikari RY, Malvankar NS, Ward JE, Nevin KP, Woodard TL, Smith JA, Snoeyenbos-West OL, Franks AE, Tuominen MT, Lovley DR. The Low Conductivity of Geobacter uraniireducens Pili Suggests a Diversity of Extracellular Electron Transfer Mechanisms in the Genus Geobacter. Front Microbiol 2016; 7:980. [PMID: 27446021 PMCID: PMC4923279 DOI: 10.3389/fmicb.2016.00980] [Citation(s) in RCA: 63] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2016] [Accepted: 06/07/2016] [Indexed: 11/30/2022] Open
Abstract
Studies on the mechanisms for extracellular electron transfer in Geobacter species have primarily focused on Geobacter sulfurreducens, but the poor conservation of genes for some electron transfer components within the Geobacter genus suggests that there may be a diversity of extracellular electron transport strategies among Geobacter species. Examination of the gene sequences for PilA, the type IV pilus monomer, in Geobacter species revealed that the PilA sequence of Geobacter uraniireducens was much longer than that of G. sulfurreducens. This is of interest because it has been proposed that the relatively short PilA sequence of G. sulfurreducens is an important feature conferring conductivity to G. sulfurreducens pili. In order to investigate the properties of the G. uraniireducens pili in more detail, a strain of G. sulfurreducens that expressed pili comprised the PilA of G. uraniireducens was constructed. This strain, designated strain GUP, produced abundant pili, but generated low current densities and reduced Fe(III) very poorly. At pH 7, the conductivity of the G. uraniireducens pili was 3 × 10-4 S/cm, much lower than the previously reported 5 × 10-2 S/cm conductivity of G. sulfurreducens pili at the same pH. Consideration of the likely voltage difference across pili during Fe(III) oxide reduction suggested that G. sulfurreducens pili can readily accommodate maximum reported rates of respiration, but that G. uraniireducens pili are not sufficiently conductive to be an effective mediator of long-range electron transfer. In contrast to G. sulfurreducens and G. metallireducens, which require direct contact with Fe(III) oxides in order to reduce them, G. uraniireducens reduced Fe(III) oxides occluded within microporous beads, demonstrating that G. uraniireducens produces a soluble electron shuttle to facilitate Fe(III) oxide reduction. The results demonstrate that Geobacter species may differ substantially in their mechanisms for long-range electron transport and that it is important to have information beyond a phylogenetic affiliation in order to make conclusions about the mechanisms by which Geobacter species are transferring electrons to extracellular electron acceptors.
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Affiliation(s)
- Yang Tan
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, USA
| | - Ramesh Y Adhikari
- Department of Physics, University of Massachusetts Amherst Amherst, MA, USA
| | - Nikhil S Malvankar
- Department of Microbiology, University of Massachusetts Amherst,Amherst, MA, USA; Department of Physics, University of Massachusetts AmherstAmherst, MA, USA; Department of Molecular Biophysics and Biochemistry, Microbial Sciences Institute, Yale UniversityNew Haven, CT, USA
| | - Joy E Ward
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, USA
| | - Kelly P Nevin
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, USA
| | - Trevor L Woodard
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, USA
| | - Jessica A Smith
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, USA
| | | | - Ashley E Franks
- Department of Microbiology, University of Massachusetts Amherst,Amherst, MA, USA; Department of Physiology, Anatomy and Microbiology, La Trobe UniversityMelbourne, VIC, Australia
| | - Mark T Tuominen
- Department of Physics, University of Massachusetts Amherst Amherst, MA, USA
| | - Derek R Lovley
- Department of Microbiology, University of Massachusetts Amherst, Amherst, MA, USA
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20
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Xiao K, Malvankar NS, Shu C, Martz E, Lovley DR, Sun X. Low Energy Atomic Models Suggesting a Pilus Structure that could Account for Electrical Conductivity of Geobacter sulfurreducens Pili. Sci Rep 2016; 6:23385. [PMID: 27001169 PMCID: PMC4802205 DOI: 10.1038/srep23385] [Citation(s) in RCA: 39] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/15/2015] [Accepted: 03/03/2016] [Indexed: 12/18/2022] Open
Abstract
The metallic-like electrical conductivity of Geobacter sulfurreducens pili has been documented with multiple lines of experimental evidence, but there is only a rudimentary understanding of the structural features which contribute to this novel mode of biological electron transport. In order to determine if it was feasible for the pilin monomers of G. sulfurreducens to assemble into a conductive filament, theoretical energy-minimized models of Geobacter pili were constructed with a previously described approach, in which pilin monomers are assembled using randomized structural parameters and distance constraints. The lowest energy models from a specific group of predicted structures lacked a central channel, in contrast to previously existing pili models. In half of the no-channel models the three N-terminal aromatic residues of the pilin monomer are arranged in a potentially electrically conductive geometry, sufficiently close to account for the experimentally observed metallic like conductivity of the pili that has been attributed to overlapping pi-pi orbitals of aromatic amino acids. These atomic resolution models capable of explaining the observed conductive properties of Geobacter pili are a valuable tool to guide further investigation of the metallic-like conductivity of the pili, their role in biogeochemical cycling, and applications in bioenergy and bioelectronics.
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Affiliation(s)
- Ke Xiao
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China.,Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Nikhil S Malvankar
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Chuanjun Shu
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China
| | - Eric Martz
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Derek R Lovley
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Xiao Sun
- State Key Laboratory of Bioelectronics, School of Biological Science and Medical Engineering, Southeast University, Nanjing, 210096, China
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21
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Abstract
Measurements of the conductivity of hydrated individual pili of Geobacter sulfurreducens that were not subjected to chemical fixation revealed conductivity along cytochrome-free regions comparable to conducting organic polymer nanowires of similar diameter.
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Affiliation(s)
| | - Nikhil S. Malvankar
- Department of Physics
- University of Massachusetts
- Amherst
- USA
- Department of Microbiology
| | | | - Derek R. Lovley
- Department of Microbiology
- University of Massachusetts
- Amherst
- USA
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22
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Lovley DR, Malvankar NS. Seeing is believing: novel imaging techniques help clarify microbial nanowire structure and function. Environ Microbiol 2015; 17:2209-15. [PMID: 25384844 DOI: 10.1111/1462-2920.12708] [Citation(s) in RCA: 53] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/09/2014] [Revised: 10/26/2014] [Accepted: 11/06/2014] [Indexed: 11/30/2022]
Abstract
Novel imaging approaches have recently helped to clarify the properties of 'microbial nanowires'. Geobacter sulfurreducens pili are actual wires. They possess metallic-like conductivity, which can be attributed to overlapping pi-pi orbitals of key aromatic amino acids. Electrostatic force microscopy recently confirmed charge propagation along the pili, in a manner similar to carbon nanotubes. The pili are essential for long-range electron transport to insoluble electron acceptors and interspecies electron transfer. Previous claims that Shewanella oneidensis also produce conductive pili have recently been recanted, based on novel live-imaging studies. The putative pili are, in fact, long extensions of the cytochrome-rich outer membrane and periplasm that, when dried, collapse to form filaments with dimensions similar to pili. It has yet to be demonstrated whether the cytochrome-to-cytochrome electron hopping documented in the dried membrane extensions takes place in intact hydrated membrane extensions or whether the membrane extensions enhance electron transport to insoluble electron acceptors such as Fe(III) oxides or electrodes. These findings demonstrate that G. sulfurreducens conductive pili and the outer membrane extensions of S. oneidensis are fundamentally different in composition, mechanism of electron transport and physiological role. New methods for evaluating filament conductivity will facilitate screening the microbial world for nanowires and elucidating their function.
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Affiliation(s)
- Derek R Lovley
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA
| | - Nikhil S Malvankar
- Department of Microbiology, University of Massachusetts, Amherst, MA, USA.,Department of Physics, University of Massachusetts, Amherst, MA, USA
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23
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Malvankar NS, Yalcin SE, Tuominen MT, Lovley DR. Visualization of charge propagation along individual pili proteins using ambient electrostatic force microscopy. Nat Nanotechnol 2014; 9:1012-7. [PMID: 25326694 DOI: 10.1038/nnano.2014.236] [Citation(s) in RCA: 124] [Impact Index Per Article: 12.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/11/2013] [Accepted: 09/15/2014] [Indexed: 05/14/2023]
Abstract
The nanoscale imaging of charge flow in proteins is crucial to understanding several life processes, including respiration, metabolism and photosynthesis. However, existing imaging methods are only effective under non-physiological conditions or are limited to photosynthetic proteins. Here, we show that electrostatic force microscopy can be used to directly visualize charge propagation along pili of Geobacter sulfurreducens with nanometre resolution and under ambient conditions. Charges injected at a single point into individual, untreated pili, which are still attached to cells, propagated over the entire filament. The mobile charge density in the pili, as well as the temperature and pH dependence of the charge density, were similar to those of carbon nanotubes and other organic conductors. These findings, coupled with a lack of charge propagation in mutated pili that were missing key aromatic amino acids, suggest that the pili of G. sulfurreducens function as molecular wires with transport via delocalized charges, rather than the hopping mechanism that is typical of biological electron transport.
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Affiliation(s)
- Nikhil S Malvankar
- 1] Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA [2] Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Sibel Ebru Yalcin
- 1] Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA [2] Department of Chemistry, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Mark T Tuominen
- Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA
| | - Derek R Lovley
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts 01003, USA
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24
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Shrestha PM, Malvankar NS, Werner JJ, Franks AE, Elena-Rotaru A, Shrestha M, Liu F, Nevin KP, Angenent LT, Lovley DR. Correlation between microbial community and granule conductivity in anaerobic bioreactors for brewery wastewater treatment. Bioresour Technol 2014; 174:306-310. [PMID: 25443621 DOI: 10.1016/j.biortech.2014.10.004] [Citation(s) in RCA: 49] [Impact Index Per Article: 4.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/27/2014] [Revised: 09/28/2014] [Accepted: 10/01/2014] [Indexed: 06/04/2023]
Abstract
Prior investigation of an upflow anaerobic sludge blanket (UASB) reactor treating brewery wastes suggested that direct interspecies electron transfer (DIET) significantly contributed to interspecies electron transfer to methanogens. To investigate DIET in granules further, the electrical conductivity and bacterial community composition of granules in fourteen samples from four different UASB reactors treating brewery wastes were investigated. All of the UASB granules were electrically conductive whereas control granules from ANAMMOX (ANaerobic AMMonium OXidation) reactors and microbial granules from an aerobic bioreactor designed for phosphate removal were not. There was a moderate correlation (r=0.67) between the abundance of Geobacter species in the UASB granules and granule conductivity, suggesting that Geobacter contributed to granule conductivity. These results, coupled with previous studies, which have demonstrated that Geobacter species can donate electrons to methanogens that are typically predominant in anaerobic digesters, suggest that DIET may be a widespread phenomenon in UASB reactors treating brewery wastes.
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Affiliation(s)
- Pravin Malla Shrestha
- Department of Microbiology, University of Massachusetts Amherst, 01003 MA, USA; Energy Biosciences Institute, University of California, Berkeley, CA, USA.
| | - Nikhil S Malvankar
- Department of Microbiology, University of Massachusetts Amherst, 01003 MA, USA
| | | | - Ashley E Franks
- Department of Microbiology, University of Massachusetts Amherst, 01003 MA, USA
| | - Amelia Elena-Rotaru
- Department of Microbiology, University of Massachusetts Amherst, 01003 MA, USA
| | - Minita Shrestha
- Department of Microbiology, University of Massachusetts Amherst, 01003 MA, USA
| | - Fanghua Liu
- Department of Microbiology, University of Massachusetts Amherst, 01003 MA, USA; Key Laboratory of Coastal Biology and Utilization, Yantai Institute of Coastal Zone Research, Chinese Academy of Sciences, Yantai, Shandong, China
| | - Kelly P Nevin
- Department of Microbiology, University of Massachusetts Amherst, 01003 MA, USA
| | - Largus T Angenent
- Biological and Environmental Engineering, Cornell University, Ithaca, NY 14853, USA
| | - Derek R Lovley
- Department of Microbiology, University of Massachusetts Amherst, 01003 MA, USA
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Malvankar NS, King GM, Lovley DR. Centimeter-long electron transport in marine sediments via conductive minerals. ISME J 2014; 9:527-31. [PMID: 25050525 DOI: 10.1038/ismej.2014.131] [Citation(s) in RCA: 40] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/10/2014] [Revised: 06/16/2014] [Accepted: 06/18/2014] [Indexed: 11/09/2022]
Abstract
Centimeter-long electron conduction through marine sediments, in which electrons derived from sulfide in anoxic sediments are transported to oxygen in surficial sediments, may have an important influence on sediment geochemistry. Filamentous bacteria have been proposed to mediate the electron transport, but the filament conductivity could not be verified and other mechanisms are possible. Surprisingly, previous investigations have never actually measured the sediment conductivity or its basic physical properties. Here we report direct measurements that demonstrate centimeter-long electron flow through marine sediments, with conductivities sufficient to account for previously estimated electron fluxes. Conductivity was lost for oxidized sediments, which contrasts with the previously described increase in the conductivity of microbial biofilms upon oxidation. Adding pyrite to the sediments significantly enhanced the conductivity. These results suggest that the role of conductive minerals, which are more commonly found in sediments than centimeter-long microbial filaments, need to be considered when modeling marine sediment biogeochemistry.
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Affiliation(s)
- Nikhil S Malvankar
- 1] Department of Physics, University of Massachusetts, Amherst, Amherst, MA, USA [2] Department of Microbiology, University of Massachusetts, Amherst, Amherst, MA, USA
| | - Gary M King
- Department of Biological Sciences, Louisiana State University, Baton Rouge, LA, USA
| | - Derek R Lovley
- Department of Microbiology, University of Massachusetts, Amherst, Amherst, MA, USA
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26
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Liu F, Rotaru AE, Shrestha PM, Malvankar NS, Nevin KP, Lovley DR. Magnetite compensates for the lack of a pilin-associatedc-type cytochrome in extracellular electron exchange. Environ Microbiol 2014; 17:648-55. [DOI: 10.1111/1462-2920.12485] [Citation(s) in RCA: 238] [Impact Index Per Article: 23.8] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/01/2013] [Accepted: 04/04/2014] [Indexed: 11/28/2022]
Affiliation(s)
- Fanghua Liu
- Department of Microbiology; University of Massachusetts; Amherst MA 01003 USA
- Key Laboratory of Coastal Biology and Utilization; Yantai Institute of Coastal Zone Research; Chinese Academy of Sciences; Yantai Shandong 264003 China
| | - Amelia-Elena Rotaru
- Department of Microbiology; University of Massachusetts; Amherst MA 01003 USA
| | - Pravin M. Shrestha
- Department of Microbiology; University of Massachusetts; Amherst MA 01003 USA
| | - Nikhil S. Malvankar
- Department of Microbiology; University of Massachusetts; Amherst MA 01003 USA
| | - Kelly P. Nevin
- Department of Microbiology; University of Massachusetts; Amherst MA 01003 USA
| | - Derek R. Lovley
- Department of Microbiology; University of Massachusetts; Amherst MA 01003 USA
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Malvankar NS, Lovley DR. Microbial nanowires: a new paradigm for biological electron transfer and bioelectronics. ChemSusChem 2012; 5:1039-1046. [PMID: 22614997 DOI: 10.1002/cssc.201100733] [Citation(s) in RCA: 124] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 11/15/2011] [Revised: 03/06/2012] [Indexed: 06/01/2023]
Abstract
The discovery that Geobacter sulfurreducens can produce protein filaments with metallic-like conductivity, known as microbial nanowires, that facilitate long-range electron transport is a paradigm shift in biological electron transfer and has important implications for biogeochemistry, microbial ecology, and the emerging field of bioelectronics. Although filaments in a wide diversity of microorganisms have been called microbial nanowires, the type IV pili of G. sulfurreducens and G. metallireducens are the only filaments that have been shown to be required for extracellular electron transport to extracellular electron acceptors or for conduction of electrons through biofilms. Studies of G. sulfurreducens pili preparations and intact biofilms under physiologically relevant conditions have provided multiple lines of evidence for metallic-like conduction along the length of pili and for the possibility of pili networks to confer high conductivity within biofilms. This mechanism of electron conduction contrasts with the previously known mechanism for biological electron transfer via electron tunneling or hopping between closely associated molecules, a strategy unlikely to be well adapted for long-range electron transport outside the cell. In addition to promoting electron exchange with abiotic electron acceptors, microbial nanowires have recently been shown to be involved in direct interspecies electron transfer between syntrophic partners. An improved understanding of the mechanisms for metallic-like conductivity in microbial nanowires, as well as engineering microorganisms with desirable catalytic abilities with nanowires, could lead to new applications in microbial electrosynthesis and bioelectronics.
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Affiliation(s)
- Nikhil S Malvankar
- Department of Microbiology, University of Massachusetts, Amherst, 203, Morrill Science Center IVN, 639 North Pleasant Street, Amherst, MA 01003, USA
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Malvankar NS, Mester T, Tuominen MT, Lovley DR. Cover Picture: Supercapacitors Based on c-Type Cytochromes Using Conductive Nanostructured Networks of Living Bacteria (ChemPhysChem 2/2012). Chemphyschem 2012. [DOI: 10.1002/cphc.201290005] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [What about the content of this article? (0)] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
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Malvankar NS, Mester T, Tuominen MT, Lovley DR. Supercapacitors based on c-type cytochromes using conductive nanostructured networks of living bacteria. Chemphyschem 2012; 13:463-8. [PMID: 22253215 DOI: 10.1002/cphc.201100865] [Citation(s) in RCA: 95] [Impact Index Per Article: 7.9] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/28/2011] [Indexed: 11/06/2022]
Abstract
Supercapacitors have attracted interest in energy storage because they have the potential to complement or replace batteries. Here, we report that c-type cytochromes, naturally immersed in a living, electrically conductive microbial biofilm, greatly enhance the device capacitance by over two orders of magnitude. We employ genetic engineering, protein unfolding and Nernstian modeling for in vivo demonstration of charge storage capacity of c-type cytochromes and perform electrochemical impedance spectroscopy, cyclic voltammetry and charge-discharge cycling to confirm the pseudocapacitive, redox nature of biofilm capacitance. The biofilms also show low self-discharge and good charge/discharge reversibility. The superior electrochemical performance of the biofilm is related to its high abundance of cytochromes, providing large electron storage capacity, its nanostructured network with metallic-like conductivity, and its porous architecture with hydrous nature, offering prospects for future low cost and environmentally sustainable energy storage devices.
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Affiliation(s)
- Nikhil S Malvankar
- Department of Physics, University of Massachusetts, Amherst, Amherst, MA 01003, USA.
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Morita M, Malvankar NS, Franks AE, Summers ZM, Giloteaux L, Rotaru AE, Rotaru C, Lovley DR. Potential for direct interspecies electron transfer in methanogenic wastewater digester aggregates. mBio 2011; 2:e00159-11. [PMID: 21862629 PMCID: PMC3157894 DOI: 10.1128/mbio.00159-11] [Citation(s) in RCA: 406] [Impact Index Per Article: 31.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/12/2011] [Accepted: 08/02/2011] [Indexed: 01/01/2023] Open
Abstract
Mechanisms for electron transfer within microbial aggregates derived from an upflow anaerobic sludge blanket reactor converting brewery waste to methane were investigated in order to better understand the function of methanogenic consortia. The aggregates were electrically conductive, with conductivities 3-fold higher than the conductivities previously reported for dual-species aggregates of Geobacter species in which the two species appeared to exchange electrons via interspecies electron transfer. The temperature dependence response of the aggregate conductance was characteristic of the organic metallic-like conductance previously described for the conductive pili of Geobacter sulfurreducens and was inconsistent with electron conduction through minerals. Studies in which aggregates were incubated with high concentrations of potential electron donors demonstrated that the aggregates had no significant capacity for conversion of hydrogen to methane. The aggregates converted formate to methane but at rates too low to account for the rates at which that the aggregates syntrophically metabolized ethanol, an important component of the reactor influent. Geobacter species comprised 25% of 16S rRNA gene sequences recovered from the aggregates, suggesting that Geobacter species may have contributed to some but probably not all of the aggregate conductivity. Microorganisms most closely related to the acetate-utilizing Methanosaeta concilii accounted for more than 90% of the sequences that could be assigned to methane producers, consistent with the poor capacity for hydrogen and formate utilization. These results demonstrate for the first time that methanogenic wastewater aggregates can be electrically conductive and suggest that direct interspecies electron transfer could be an important mechanism for electron exchange in some methanogenic systems.
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Affiliation(s)
| | | | - Ashley E. Franks
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Zarath M. Summers
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Ludovic Giloteaux
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Amelia E. Rotaru
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
| | - Camelia Rotaru
- Civil and Environmental Engineering Department, University of Massachusetts, Amherst, Massachusetts, USA
| | - Derek R. Lovley
- Department of Microbiology, University of Massachusetts, Amherst, Massachusetts, USA
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Malvankar NS, Vargas M, Nevin KP, Franks AE, Leang C, Kim BC, Inoue K, Mester T, Covalla SF, Johnson JP, Rotello VM, Tuominen MT, Lovley DR. Tunable metallic-like conductivity in microbial nanowire networks. Nat Nanotechnol 2011; 6:573-9. [PMID: 21822253 DOI: 10.1038/nnano.2011.119] [Citation(s) in RCA: 468] [Impact Index Per Article: 36.0] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/18/2011] [Accepted: 06/23/2011] [Indexed: 05/05/2023]
Abstract
Electronic nanostructures made from natural amino acids are attractive because of their relatively low cost, facile processing and absence of toxicity. However, most materials derived from natural amino acids are electronically insulating. Here, we report metallic-like conductivity in films of the bacterium Geobacter sulfurreducens and also in pilin nanofilaments (known as microbial nanowires) extracted from these bacteria. These materials have electronic conductivities of ∼5 mS cm(-1), which are comparable to those of synthetic metallic nanostructures. They can also conduct over distances on the centimetre scale, which is thousands of times the size of a bacterium. Moreover, the conductivity of the biofilm can be tuned by regulating gene expression, and also by varying the gate voltage in a transistor configuration. The conductivity of the nanofilaments has a temperature dependence similar to that of a disordered metal, and the conductivity could be increased by processing.
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Affiliation(s)
- Nikhil S Malvankar
- Department of Physics, University of Massachusetts, Amherst, Massachusetts 01003, USA
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Lovley DR, Ueki T, Zhang T, Malvankar NS, Shrestha PM, Flanagan KA, Aklujkar M, Butler JE, Giloteaux L, Rotaru AE, Holmes DE, Franks AE, Orellana R, Risso C, Nevin KP. Geobacter: the microbe electric's physiology, ecology, and practical applications. Adv Microb Physiol 2011; 59:1-100. [PMID: 22114840 DOI: 10.1016/b978-0-12-387661-4.00004-5] [Citation(s) in RCA: 380] [Impact Index Per Article: 29.2] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Geobacter species specialize in making electrical contacts with extracellular electron acceptors and other organisms. This permits Geobacter species to fill important niches in a diversity of anaerobic environments. Geobacter species appear to be the primary agents for coupling the oxidation of organic compounds to the reduction of insoluble Fe(III) and Mn(IV) oxides in many soils and sediments, a process of global biogeochemical significance. Some Geobacter species can anaerobically oxidize aromatic hydrocarbons and play an important role in aromatic hydrocarbon removal from contaminated aquifers. The ability of Geobacter species to reductively precipitate uranium and related contaminants has led to the development of bioremediation strategies for contaminated environments. Geobacter species produce higher current densities than any other known organism in microbial fuel cells and are common colonizers of electrodes harvesting electricity from organic wastes and aquatic sediments. Direct interspecies electron exchange between Geobacter species and syntrophic partners appears to be an important process in anaerobic wastewater digesters. Functional and comparative genomic studies have begun to reveal important aspects of Geobacter physiology and regulation, but much remains unexplored. Quantifying key gene transcripts and proteins of subsurface Geobacter communities has proven to be a powerful approach to diagnose the in situ physiological status of Geobacter species during groundwater bioremediation. The growth and activity of Geobacter species in the subsurface and their biogeochemical impact under different environmental conditions can be predicted with a systems biology approach in which genome-scale metabolic models are coupled with appropriate physical/chemical models. The proficiency of Geobacter species in transferring electrons to insoluble minerals, electrodes, and possibly other microorganisms can be attributed to their unique "microbial nanowires," pili that conduct electrons along their length with metallic-like conductivity. Surprisingly, the abundant c-type cytochromes of Geobacter species do not contribute to this long-range electron transport, but cytochromes are important for making the terminal electrical connections with Fe(III) oxides and electrodes and also function as capacitors, storing charge to permit continued respiration when extracellular electron acceptors are temporarily unavailable. The high conductivity of Geobacter pili and biofilms and the ability of biofilms to function as supercapacitors are novel properties that might contribute to the field of bioelectronics. The study of Geobacter species has revealed a remarkable number of microbial physiological properties that had not previously been described in any microorganism. Further investigation of these environmentally relevant and physiologically unique organisms is warranted.
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Affiliation(s)
- Derek R Lovley
- Department of Microbiology and Environmental Biotechnology Center, University of Massachusetts, Amherst, Massachusetts, USA
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Summers ZM, Fogarty HE, Leang C, Franks AE, Malvankar NS, Lovley DR. Direct exchange of electrons within aggregates of an evolved syntrophic coculture of anaerobic bacteria. Science 2010; 330:1413-5. [PMID: 21127257 DOI: 10.1126/science.1196526] [Citation(s) in RCA: 509] [Impact Index Per Article: 36.4] [Reference Citation Analysis] [What about the content of this article? (0)] [Affiliation(s)] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/02/2022]
Abstract
Microbial consortia that cooperatively exchange electrons play a key role in the anaerobic processing of organic matter. Interspecies hydrogen transfer is a well-documented strategy for electron exchange in dispersed laboratory cultures, but cooperative partners in natural environments often form multispecies aggregates. We found that laboratory evolution of a coculture of Geobacter metallireducens and Geobacter sulfurreducens metabolizing ethanol favored the formation of aggregates that were electrically conductive. Sequencing aggregate DNA revealed selection for a mutation that enhances the production of a c-type cytochrome involved in extracellular electron transfer and accelerates the formation of aggregates. Aggregate formation was also much faster in mutants that were deficient in interspecies hydrogen transfer, further suggesting direct interspecies electron transfer.
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Affiliation(s)
- Zarath M Summers
- Department of Microbiology, University of Massachusetts, Amherst, MA 01003, USA
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