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Harris DF, Rucker HR, Garcia AK, Yang ZY, Chang SD, Feinsilber H, Kaçar B, Seefeldt LC. Ancient nitrogenases are ATP dependent. mBio 2024:e0127124. [PMID: 38869277 DOI: 10.1128/mbio.01271-24] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/29/2024] [Accepted: 05/03/2024] [Indexed: 06/14/2024] Open
Abstract
Life depends on a conserved set of chemical energy currencies that are relics of early biochemistry. One of these is ATP, a molecule that, when paired with a divalent metal ion such as Mg2+, can be hydrolyzed to support numerous cellular and molecular processes. Despite its centrality to extant biochemistry, it is unclear whether ATP supported the function of ancient enzymes. We investigate the evolutionary necessity of ATP by experimentally reconstructing an ancestral variant of the N2-reducing enzyme nitrogenase. The Proterozoic ancestor is predicted to be ~540-2,300 million years old, post-dating the Great Oxidation Event. Growth rates under nitrogen-fixing conditions are ~80% of those of wild type in Azotobacter vinelandii. In the extant enzyme, the hydrolysis of two MgATP is coupled to electron transfer to support substrate reduction. The ancestor has a strict requirement for ATP with no other nucleotide triphosphate analogs (GTP, ITP, and UTP) supporting activity. Alternative divalent metal ions (Fe2+, Co2+, and Mn2+) support activity with ATP but with diminished activities compared to Mg2+, similar to the extant enzyme. Additionally, it is shown that the ancestor has an identical efficiency in ATP hydrolyzed per electron transferred to the extant of two. Our results provide direct laboratory evidence of ATP usage by an ancient enzyme.IMPORTANCELife depends on energy-carrying molecules to power many sustaining processes. There is evidence that these molecules may predate the rise of life on Earth, but how and when these dependencies formed is unknown. The resurrection of ancient enzymes provides a unique tool to probe the enzyme's function and usage of energy-carrying molecules, shedding light on their biochemical origins. Through experimental reconstruction, this research investigates the ancestral dependence of a nitrogen-fixing enzyme on the energy carrier ATP, a requirement for function in the modern enzyme. We show that the resurrected ancestor does not have generalist nucleotide specificity. Rather, the ancestor has a strict requirement for ATP, like the modern enzyme, with similar function and efficiency. The findings elucidate the early-evolved necessity of energy-yielding molecules, delineating their role in ancient biochemical processes. Ultimately, these insights contribute to unraveling the intricate tapestry of evolutionary biology and the origins of life-sustaining dependencies.
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Affiliation(s)
- Derek F Harris
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah, USA
| | - Holly R Rucker
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Amanda K Garcia
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Zhi-Yong Yang
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah, USA
| | - Scott D Chang
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Hannah Feinsilber
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah, USA
| | - Betül Kaçar
- Department of Bacteriology, University of Wisconsin-Madison, Madison, Wisconsin, USA
| | - Lance C Seefeldt
- Department of Chemistry and Biochemistry, Utah State University, Logan, Utah, USA
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2
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Goldford JE, Smith HB, Longo LM, Wing BA, McGlynn SE. Primitive purine biosynthesis connects ancient geochemistry to modern metabolism. Nat Ecol Evol 2024; 8:999-1009. [PMID: 38519634 DOI: 10.1038/s41559-024-02361-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/21/2022] [Accepted: 02/06/2024] [Indexed: 03/25/2024]
Abstract
An unresolved question in the origin and evolution of life is whether a continuous path from geochemical precursors to the majority of molecules in the biosphere can be reconstructed from modern-day biochemistry. Here we identified a feasible path by simulating the evolution of biosphere-scale metabolism, using only known biochemical reactions and models of primitive coenzymes. We find that purine synthesis constitutes a bottleneck for metabolic expansion, which can be alleviated by non-autocatalytic phosphoryl coupling agents. Early phases of the expansion are enriched with enzymes that are metal dependent and structurally symmetric, supporting models of early biochemical evolution. This expansion trajectory suggests distinct hypotheses regarding the tempo, mode and timing of metabolic pathway evolution, including a late appearance of methane metabolisms and oxygenic photosynthesis consistent with the geochemical record. The concordance between biological and geological analyses suggests that this trajectory provides a plausible evolutionary history for the vast majority of core biochemistry.
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Affiliation(s)
- Joshua E Goldford
- Division of Geological and Planetary Sciences, California Institute of Technology, Pasadena, CA, USA.
- Physics of Living Systems, Massachusetts Institute of Technology, Cambridge, MA, USA.
- Blue Marble Space Institute of Science, Seattle, WA, USA.
| | - Harrison B Smith
- Blue Marble Space Institute of Science, Seattle, WA, USA
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Liam M Longo
- Blue Marble Space Institute of Science, Seattle, WA, USA
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan
| | - Boswell A Wing
- Department of Geological Sciences, University of Colorado, Boulder, CO, USA
| | - Shawn Erin McGlynn
- Blue Marble Space Institute of Science, Seattle, WA, USA.
- Earth-Life Science Institute, Tokyo Institute of Technology, Tokyo, Japan.
- Biofunctional Catalyst Research Team, RIKEN Center for Sustainable Resource Science, Wako, Japan.
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3
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Fujikawa T, Sasamoto T, Zhao F, Yamagishi A, Akanuma S. Comparative analysis of reconstructed ancestral proteins with their extant counterparts suggests primitive life had an alkaline habitat. Sci Rep 2024; 14:398. [PMID: 38172176 PMCID: PMC10764835 DOI: 10.1038/s41598-023-50828-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2023] [Accepted: 12/26/2023] [Indexed: 01/05/2024] Open
Abstract
To understand the origin and early evolution of life it is crucial to establish characteristics of the primordial environment that facilitated the emergence and evolution of life. One important environmental factor is the pH of the primordial environment. Here, we assessed the pH-dependent thermal stabilities of previously reconstructed ancestral nucleoside diphosphate kinases and ribosomal protein uS8s. The selected proteins were likely to be present in ancient organisms such as the last common ancestor of bacteria and that of archaea. We also assessed the thermal stability of homologous proteins from extant acidophilic, neutralophilic, and alkaliphilic microorganisms as a function of pH. Our results indicate that the reconstructed ancestral proteins are more akin to those of extant alkaliphilic bacteria, which display greater stability under alkaline conditions. These findings suggest that the common ancestors of bacterial and archaeal species thrived in an alkaline environment. Moreover, we demonstrate the reconstruction method employed in this study is a valuable technique for generating alkali-tolerant proteins that can be used in a variety of biotechnological and environmental applications.
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Affiliation(s)
- Takayuki Fujikawa
- Faculty of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192, Japan
| | - Takahiro Sasamoto
- Department of Applied Life Science, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Fangzheng Zhao
- Faculty of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192, Japan
| | - Akihiko Yamagishi
- Department of Applied Life Science, Tokyo University of Pharmacy and Life Sciences, 1432-1 Horinouchi, Hachioji, Tokyo, 192-0392, Japan
| | - Satoshi Akanuma
- Faculty of Human Sciences, Waseda University, 2-579-15 Mikajima, Tokorozawa, Saitama, 359-1192, Japan.
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4
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Nicholls JWF, Chin JP, Williams TA, Lenton TM, O’Flaherty V, McGrath JW. On the potential roles of phosphorus in the early evolution of energy metabolism. Front Microbiol 2023; 14:1239189. [PMID: 37601379 PMCID: PMC10433651 DOI: 10.3389/fmicb.2023.1239189] [Citation(s) in RCA: 4] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/13/2023] [Accepted: 07/20/2023] [Indexed: 08/22/2023] Open
Abstract
Energy metabolism in extant life is centered around phosphate and the energy-dense phosphoanhydride bonds of adenosine triphosphate (ATP), a deeply conserved and ancient bioenergetic system. Yet, ATP synthesis relies on numerous complex enzymes and has an autocatalytic requirement for ATP itself. This implies the existence of evolutionarily simpler bioenergetic pathways and potentially primordial alternatives to ATP. The centrality of phosphate in modern bioenergetics, coupled with the energetic properties of phosphorylated compounds, may suggest that primordial precursors to ATP also utilized phosphate in compounds such as pyrophosphate, acetyl phosphate and polyphosphate. However, bioavailable phosphate may have been notably scarce on the early Earth, raising doubts about the roles that phosphorylated molecules might have played in the early evolution of life. A largely overlooked phosphorus redox cycle on the ancient Earth might have provided phosphorus and energy, with reduced phosphorus compounds potentially playing a key role in the early evolution of energy metabolism. Here, we speculate on the biological phosphorus compounds that may have acted as primordial energy currencies, sources of environmental energy, or sources of phosphorus for the synthesis of phosphorylated energy currencies. This review encompasses discussions on the evolutionary history of modern bioenergetics, and specifically those pathways with primordial relevance, and the geochemistry of bioavailable phosphorus on the ancient Earth. We highlight the importance of phosphorus, not only in the form of phosphate, to early biology and suggest future directions of study that may improve our understanding of the early evolution of bioenergetics.
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Affiliation(s)
- Jack W. F. Nicholls
- School of Biological Sciences, Queen’s University of Belfast, Belfast, United Kingdom
| | - Jason P. Chin
- School of Biological Sciences, Queen’s University of Belfast, Belfast, United Kingdom
| | - Tom A. Williams
- School of Biological Sciences, University of Bristol, Bristol, United Kingdom
| | - Timothy M. Lenton
- Global Systems Institute, University of Exeter, Exeter, United Kingdom
| | | | - John W. McGrath
- School of Biological Sciences, Queen’s University of Belfast, Belfast, United Kingdom
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Kranz SA. Insights into the biological control of the carbon isotope signatures of ancient aquatic organisms. Proc Natl Acad Sci U S A 2023; 120:e2306683120. [PMID: 37228114 PMCID: PMC10265943 DOI: 10.1073/pnas.2306683120] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/27/2023] Open
Affiliation(s)
- Sven A. Kranz
- Department of Earth, Ocean and Atmospheric Science, Florida State University, Tallahassee, FL32306
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Garcia AK, Kędzior M, Taton A, Li M, Young JN, Kaçar B. Effects of RuBisCO and CO 2 concentration on cyanobacterial growth and carbon isotope fractionation. GEOBIOLOGY 2023; 21:390-403. [PMID: 36602111 DOI: 10.1111/gbi.12543] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/22/2022] [Revised: 11/11/2022] [Accepted: 12/19/2022] [Indexed: 06/17/2023]
Abstract
Carbon isotope biosignatures preserved in the Precambrian geologic record are primarily interpreted to reflect ancient cyanobacterial carbon fixation catalyzed by Form I RuBisCO enzymes. The average range of isotopic biosignatures generally follows that produced by extant cyanobacteria. However, this observation is difficult to reconcile with several environmental (e.g., temperature, pH, and CO2 concentrations), molecular, and physiological factors that likely would have differed during the Precambrian and can produce fractionation variability in contemporary organisms that meets or exceeds that observed in the geologic record. To test a specific range of genetic and environmental factors that may impact ancient carbon isotope biosignatures, we engineered a mutant strain of the model cyanobacterium Synechococcus elongatus PCC 7942 that overexpresses RuBisCO across varying atmospheric CO2 concentrations. We hypothesized that changes in RuBisCO expression would impact the net rates of intracellular CO2 fixation versus CO2 supply, and thus whole-cell carbon isotope discrimination. In particular, we investigated the impacts of RuBisCO overexpression under changing CO2 concentrations on both carbon isotope biosignatures and cyanobacterial physiology, including cell growth and oxygen evolution rates. We found that an increased pool of active RuBisCO does not significantly affect the 13 C/12 C isotopic discrimination (εp ) at all tested CO2 concentrations, yielding εp of ≈ 23‰ for both wild-type and mutant strains at elevated CO2 . We therefore suggest that expected variation in cyanobacterial RuBisCO expression patterns should not confound carbon isotope biosignature interpretation. A deeper understanding of environmental, evolutionary, and intracellular factors that impact cyanobacterial physiology and isotope discrimination is crucial for reconciling microbially driven carbon biosignatures with those preserved in the geologic record.
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Affiliation(s)
- Amanda K Garcia
- Department of Bacteriology, University of Wisconsin - Madison, Madison, Wisconsin, USA
| | - Mateusz Kędzior
- Department of Bacteriology, University of Wisconsin - Madison, Madison, Wisconsin, USA
| | - Arnaud Taton
- Division of Biological Sciences, University of California San Diego, La Jolla, California, USA
| | - Meng Li
- School of Oceanography, University of Washington, Seattle, Washington, USA
| | - Jodi N Young
- School of Oceanography, University of Washington, Seattle, Washington, USA
| | - Betül Kaçar
- Department of Bacteriology, University of Wisconsin - Madison, Madison, Wisconsin, USA
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7
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Garcia AK, Harris DF, Rivier AJ, Carruthers BM, Pinochet-Barros A, Seefeldt LC, Kaçar B. Nitrogenase resurrection and the evolution of a singular enzymatic mechanism. eLife 2023; 12:e85003. [PMID: 36799917 PMCID: PMC9977276 DOI: 10.7554/elife.85003] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/18/2022] [Accepted: 02/16/2023] [Indexed: 02/18/2023] Open
Abstract
The planetary biosphere is powered by a suite of key metabolic innovations that emerged early in the history of life. However, it is unknown whether life has always followed the same set of strategies for performing these critical tasks. Today, microbes access atmospheric sources of bioessential nitrogen through the activities of just one family of enzymes, nitrogenases. Here, we show that the only dinitrogen reduction mechanism known to date is an ancient feature conserved from nitrogenase ancestors. We designed a paleomolecular engineering approach wherein ancestral nitrogenase genes were phylogenetically reconstructed and inserted into the genome of the diazotrophic bacterial model, Azotobacter vinelandii, enabling an integrated assessment of both in vivo functionality and purified nitrogenase biochemistry. Nitrogenase ancestors are active and robust to variable incorporation of one or more ancestral protein subunits. Further, we find that all ancestors exhibit the reversible enzymatic mechanism for dinitrogen reduction, specifically evidenced by hydrogen inhibition, which is also exhibited by extant A. vinelandii nitrogenase isozymes. Our results suggest that life may have been constrained in its sampling of protein sequence space to catalyze one of the most energetically challenging biochemical reactions in nature. The experimental framework established here is essential for probing how nitrogenase functionality has been shaped within a dynamic, cellular context to sustain a globally consequential metabolism.
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Affiliation(s)
- Amanda K Garcia
- Department of Bacteriology, University of Wisconsin–MadisonMadisonUnited States
| | - Derek F Harris
- Department of Chemistry and Biochemistry, Utah State UniversityLoganUnited States
| | - Alex J Rivier
- Department of Bacteriology, University of Wisconsin–MadisonMadisonUnited States
| | - Brooke M Carruthers
- Department of Bacteriology, University of Wisconsin–MadisonMadisonUnited States
| | | | - Lance C Seefeldt
- Department of Chemistry and Biochemistry, Utah State UniversityLoganUnited States
| | - Betül Kaçar
- Department of Bacteriology, University of Wisconsin–MadisonMadisonUnited States
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8
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Zhao F, Akanuma S. Ancestral Sequence Reconstruction of the Ribosomal Protein uS8 and Reduction of Amino Acid Usage to a Smaller Alphabet. J Mol Evol 2023; 91:10-23. [PMID: 36396786 DOI: 10.1007/s00239-022-10078-w] [Citation(s) in RCA: 1] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/14/2022] [Accepted: 11/08/2022] [Indexed: 11/19/2022]
Abstract
Understanding the origin and early evolution of proteins is important for unveiling how the RNA world developed into an RNA-protein world. Because the composition of organic molecules in the Earth's primitive environment was plausibly not as diverse as today, the number of different amino acids used in early protein synthesis is likely to be substantially less than the current 20 proteinogenic residues. In this study, we have explored the thermal stability and RNA binding of ancestral variants of the ribosomal protein uS8 constructed from a reduced-alphabet of amino acids. First, we built a phylogenetic tree based on the amino acid sequences of uS8 from multiple extant organisms and used the tree to infer two plausible amino acid sequences corresponding to the last bacterial common ancestor of uS8. Both ancestral proteins were thermally stable and bound to an RNA fragment. By eliminating individual amino acid letters and monitoring thermal stability and RNA binding in the resulting proteins, we reduced the size of the amino acid set constituting one of the ancestral proteins, eventually finding that convergent sequences consisting of 15- or 14-amino acid alphabets still folded into stable structures that bound to the RNA fragment. Furthermore, a simplified variant reconstructed from a 13-amino-acid alphabet retained affinity for the RNA fragment, although it lost conformational stability. Collectively, RNA-binding activity may be achieved with a subset of the current 20 amino acids, raising the possibility of a simpler composition of RNA-binding proteins in the earliest stage of protein evolution.
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Affiliation(s)
- Fangzheng Zhao
- Faculty of Human Sciences, Waseda University, 2-579-15, Mikajima, Tokorozawa, Saitama, 359-1192, Japan
| | - Satoshi Akanuma
- Faculty of Human Sciences, Waseda University, 2-579-15, Mikajima, Tokorozawa, Saitama, 359-1192, Japan.
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9
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Badger MR, Sharwood RE. Rubisco, the imperfect winner: it's all about the base. JOURNAL OF EXPERIMENTAL BOTANY 2023; 74:562-580. [PMID: 36412307 DOI: 10.1093/jxb/erac458] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 06/28/2022] [Accepted: 11/20/2022] [Indexed: 06/16/2023]
Abstract
Rubisco catalysis is complex and includes an activation step through the formation of a carbamate at the conserved active site lysine residue and the formation of a highly reactive enediol that is the key to its catalytic reaction. The formation of this enediol is both the basis of its success and its Achilles' heel, creating imperfections to its catalytic efficiency. While Rubisco originally evolved in an atmosphere of high CO2, the earth's multiple oxidation events provided challenges to Rubisco through the fixation of O2 that competes with CO2 at the active site. Numerous catalytic screens across the Rubisco superfamily have identified significant variation in catalytic properties that have been linked to large and small subunit sequences. Despite this, we still have a rudimentary understanding of Rubisco's catalytic mechanism and how the evolution of kinetic properties has occurred. This review identifies the lysine base that functions both as an activator and a proton abstractor to create the enediol as a key to understanding how Rubisco may optimize its kinetic properties. The ways in which Rubisco and its partners have overcome catalytic and activation imperfections and thrived in a world of high O2, low CO2, and variable climatic regimes is remarkable.
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Affiliation(s)
- Murray R Badger
- Research School of Biology, Building 134 Linnaeus Way, Canberra ACT, 2601, Australia
| | - Robert E Sharwood
- Hawkesbury Institute for the Environment, Western Sydney University, Bourke St, Richmond, NSW, 2753, Australia
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10
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Sloan DB, Warren JM, Williams AM, Kuster SA, Forsythe ES. Incompatibility and Interchangeability in Molecular Evolution. Genome Biol Evol 2023; 15:evac184. [PMID: 36583227 PMCID: PMC9839398 DOI: 10.1093/gbe/evac184] [Citation(s) in RCA: 3] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/01/2022] [Revised: 12/20/2022] [Accepted: 12/22/2022] [Indexed: 12/31/2022] Open
Abstract
There is remarkable variation in the rate at which genetic incompatibilities in molecular interactions accumulate. In some cases, minor changes-even single-nucleotide substitutions-create major incompatibilities when hybridization forces new variants to function in a novel genetic background from an isolated population. In other cases, genes or even entire functional pathways can be horizontally transferred between anciently divergent evolutionary lineages that span the tree of life with little evidence of incompatibilities. In this review, we explore whether there are general principles that can explain why certain genes are prone to incompatibilities while others maintain interchangeability. We summarize evidence pointing to four genetic features that may contribute to greater resistance to functional replacement: (1) function in multisubunit enzyme complexes and protein-protein interactions, (2) sensitivity to changes in gene dosage, (3) rapid rate of sequence evolution, and (4) overall importance to cell viability, which creates sensitivity to small perturbations in molecular function. We discuss the relative levels of support for these different hypotheses and lay out future directions that may help explain the striking contrasts in patterns of incompatibility and interchangeability throughout the history of molecular evolution.
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Affiliation(s)
- Daniel B Sloan
- Department of Biology, Colorado State University, Fort Collins, Colorado
| | - Jessica M Warren
- Center for Mechanisms of Evolution, Biodesign Institute and School of Life Sciences, Arizona State University, Tempe, Arizona
| | - Alissa M Williams
- Department of Biological Sciences, Vanderbilt University, Nashville, Tennessee
| | - Shady A Kuster
- Department of Biology, Colorado State University, Fort Collins, Colorado
| | - Evan S Forsythe
- Department of Biology, Colorado State University, Fort Collins, Colorado
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11
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Garcia AK, Fer E, Sephus C, Kacar B. An Integrated Method to Reconstruct Ancient Proteins. Methods Mol Biol 2022; 2569:267-281. [PMID: 36083453 DOI: 10.1007/978-1-0716-2691-7_13] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/24/2023]
Abstract
Proteins have played a fundamental role throughout life's history on Earth. Despite their biological importance, ancient origin, early function, and evolution of proteins are seldom able to be directly studied because few of these attributes are preserved across geologic timescales. Ancestral sequence reconstruction (ASR) provides a method to infer ancestral amino acid sequences and determine the evolutionary predecessors of modern-day proteins using phylogenetic tools. Laboratory application of ASR allows ancient sequences to be deduced from genetic information available in extant organisms and then experimentally resurrected to elucidate ancestral characteristics. In this article, we provide a generalized, stepwise protocol that considers the major elements of a well-designed ASR study and details potential sources of reconstruction bias that can reduce the relevance of historical inferences. We underscore key stages in our approach so that it may be broadly utilized to reconstruct the evolutionary histories of proteins.
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Affiliation(s)
- Amanda K Garcia
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
| | - Evrim Fer
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA
- Microbiology Doctoral Training Program, University of Wisconsin-Madison, Madison, WI, USA
| | - Cathryn Sephus
- Scripps Institution of Oceanography, University of California at San Diego, La Jolla, CA, USA
| | - Betul Kacar
- Department of Bacteriology, University of Wisconsin-Madison, Madison, WI, USA.
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