1
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Birch-Price Z, Hardy FJ, Lister TM, Kohn AR, Green AP. Noncanonical Amino Acids in Biocatalysis. Chem Rev 2024; 124:8740-8786. [PMID: 38959423 PMCID: PMC11273360 DOI: 10.1021/acs.chemrev.4c00120] [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: 02/09/2024] [Revised: 06/11/2024] [Accepted: 06/12/2024] [Indexed: 07/05/2024]
Abstract
In recent years, powerful genetic code reprogramming methods have emerged that allow new functional components to be embedded into proteins as noncanonical amino acid (ncAA) side chains. In this review, we will illustrate how the availability of an expanded set of amino acid building blocks has opened a wealth of new opportunities in enzymology and biocatalysis research. Genetic code reprogramming has provided new insights into enzyme mechanisms by allowing introduction of new spectroscopic probes and the targeted replacement of individual atoms or functional groups. NcAAs have also been used to develop engineered biocatalysts with improved activity, selectivity, and stability, as well as enzymes with artificial regulatory elements that are responsive to external stimuli. Perhaps most ambitiously, the combination of genetic code reprogramming and laboratory evolution has given rise to new classes of enzymes that use ncAAs as key catalytic elements. With the framework for developing ncAA-containing biocatalysts now firmly established, we are optimistic that genetic code reprogramming will become a progressively more powerful tool in the armory of enzyme designers and engineers in the coming years.
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Affiliation(s)
| | | | | | | | - Anthony P. Green
- Manchester Institute of Biotechnology,
School of Chemistry, University of Manchester, Manchester M1 7DN, U.K.
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2
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Rizo J, Encarnación-Guevara S. Bacterial protein acetylation: mechanisms, functions, and methods for study. Front Cell Infect Microbiol 2024; 14:1408947. [PMID: 39027134 PMCID: PMC11254643 DOI: 10.3389/fcimb.2024.1408947] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/29/2024] [Accepted: 06/03/2024] [Indexed: 07/20/2024] Open
Abstract
Lysine acetylation is an evolutionarily conserved protein modification that changes protein functions and plays an essential role in many cellular processes, such as central metabolism, transcriptional regulation, chemotaxis, and pathogen virulence. It can alter DNA binding, enzymatic activity, protein-protein interactions, protein stability, or protein localization. In prokaryotes, lysine acetylation occurs non-enzymatically and by the action of lysine acetyltransferases (KAT). In enzymatic acetylation, KAT transfers the acetyl group from acetyl-CoA (AcCoA) to the lysine side chain. In contrast, acetyl phosphate (AcP) is the acetyl donor of chemical acetylation. Regardless of the acetylation type, the removal of acetyl groups from acetyl lysines occurs only enzymatically by lysine deacetylases (KDAC). KATs are grouped into three main superfamilies based on their catalytic domain sequences and biochemical characteristics of catalysis. Specifically, members of the GNAT are found in eukaryotes and prokaryotes and have a core structural domain architecture. These enzymes can acetylate small molecules, metabolites, peptides, and proteins. This review presents current knowledge of acetylation mechanisms and functional implications in bacterial metabolism, pathogenicity, stress response, translation, and the emerging topic of protein acetylation in the gut microbiome. Additionally, the methods used to elucidate the biological significance of acetylation in bacteria, such as relative quantification and stoichiometry quantification, and the genetic code expansion tool (CGE), are reviewed.
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Affiliation(s)
| | - Sergio Encarnación-Guevara
- Laboratorio de Proteómica, Centro de Ciencias Genómicas, Universidad Nacional Autónoma de México, Cuernavaca, Mexico
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3
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Weyh M, Jokisch ML, Nguyen TA, Fottner M, Lang K. Deciphering functional roles of protein succinylation and glutarylation using genetic code expansion. Nat Chem 2024; 16:913-921. [PMID: 38531969 PMCID: PMC11164685 DOI: 10.1038/s41557-024-01500-5] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/19/2023] [Accepted: 03/01/2024] [Indexed: 03/28/2024]
Abstract
Post-translational modifications (PTMs) dynamically regulate cellular processes. Lysine undergoes a range of acylations, including malonylation, succinylation (SucK) and glutarylation (GluK). These PTMs increase the size of the lysine side chain and reverse its charge from +1 to -1 under physiological conditions, probably impacting protein structure and function. To understand the functional roles of these PTMs, homogeneously modified proteins are required for biochemical studies. While the site-specific encoding of PTMs and their mimics via genetic code expansion has facilitated the characterization of the functional roles of many PTMs, negatively charged lysine acylations have defied this approach. Here we describe site-specific incorporation of SucK and GluK into proteins via temporarily masking their negative charge through thioester derivatives. We prepare succinylated and glutarylated bacterial and mammalian target proteins, including non-refoldable multidomain proteins. This allows us to study how succinylation and glutarylation impact enzymatic activity of metabolic enzymes and regulate protein-DNA and protein-protein interactions in biological processes from replication to ubiquitin signalling.
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Affiliation(s)
- Maria Weyh
- Laboratory for Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Marie-Lena Jokisch
- Laboratory for Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland
| | - Tuan-Anh Nguyen
- Department of Chemistry, Laboratory for Synthetic Biochemistry, Technical University of Munich Institute for Advanced Study, Garching, Germany
- CeMM Research Center for Molecular Medicine, Austrian Academy of Sciences, Vienna, Austria
| | - Maximilian Fottner
- Laboratory for Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland.
| | - Kathrin Lang
- Laboratory for Organic Chemistry, Department of Chemistry and Applied Biosciences, ETH Zurich, Zurich, Switzerland.
- Department of Chemistry, Laboratory for Synthetic Biochemistry, Technical University of Munich Institute for Advanced Study, Garching, Germany.
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4
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Allen MC, Karplus PA, Mehl RA, Cooley RB. Genetic Encoding of Phosphorylated Amino Acids into Proteins. Chem Rev 2024; 124:6592-6642. [PMID: 38691379 DOI: 10.1021/acs.chemrev.4c00110] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 05/03/2024]
Abstract
Reversible phosphorylation is a fundamental mechanism for controlling protein function. Despite the critical roles phosphorylated proteins play in physiology and disease, our ability to study individual phospho-proteoforms has been hindered by a lack of versatile methods to efficiently generate homogeneous proteins with site-specific phosphoamino acids or with functional mimics that are resistant to phosphatases. Genetic code expansion (GCE) is emerging as a transformative approach to tackle this challenge, allowing direct incorporation of phosphoamino acids into proteins during translation in response to amber stop codons. This genetic programming of phospho-protein synthesis eliminates the reliance on kinase-based or chemical semisynthesis approaches, making it broadly applicable to diverse phospho-proteoforms. In this comprehensive review, we provide a brief introduction to GCE and trace the development of existing GCE technologies for installing phosphoserine, phosphothreonine, phosphotyrosine, and their mimics, discussing both their advantages as well as their limitations. While some of the technologies are still early in their development, others are already robust enough to greatly expand the range of biologically relevant questions that can be addressed. We highlight new discoveries enabled by these GCE approaches, provide practical considerations for the application of technologies by non-GCE experts, and also identify avenues ripe for further development.
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Affiliation(s)
- Michael C Allen
- Department of Biochemistry and Biophysics, Oregon State University, GCE4All Research Center, 2011 Agricultural and Life Sciences, Corvallis, Oregon 97331 United States
| | - P Andrew Karplus
- Department of Biochemistry and Biophysics, Oregon State University, GCE4All Research Center, 2011 Agricultural and Life Sciences, Corvallis, Oregon 97331 United States
| | - Ryan A Mehl
- Department of Biochemistry and Biophysics, Oregon State University, GCE4All Research Center, 2011 Agricultural and Life Sciences, Corvallis, Oregon 97331 United States
| | - Richard B Cooley
- Department of Biochemistry and Biophysics, Oregon State University, GCE4All Research Center, 2011 Agricultural and Life Sciences, Corvallis, Oregon 97331 United States
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5
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Gan Q, Fan C. Orthogonal Translation for Site-Specific Installation of Post-translational Modifications. Chem Rev 2024; 124:2805-2838. [PMID: 38373737 PMCID: PMC11230630 DOI: 10.1021/acs.chemrev.3c00850] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/21/2024]
Abstract
Post-translational modifications (PTMs) endow proteins with new properties to respond to environmental changes or growth needs. With the development of advanced proteomics techniques, hundreds of distinct types of PTMs have been observed in a wide range of proteins from bacteria, archaea, and eukarya. To identify the roles of these PTMs, scientists have applied various approaches. However, high dynamics, low stoichiometry, and crosstalk between PTMs make it almost impossible to obtain homogeneously modified proteins for characterization of the site-specific effect of individual PTM on target proteins. To solve this problem, the genetic code expansion (GCE) strategy has been introduced into the field of PTM studies. Instead of modifying proteins after translation, GCE incorporates modified amino acids into proteins during translation, thus generating site-specifically modified proteins at target positions. In this review, we summarize the development of GCE systems for orthogonal translation for site-specific installation of PTMs.
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Affiliation(s)
- Qinglei Gan
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, United States
| | - Chenguang Fan
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas 72701, United States
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, Arkansas 72701, United States
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6
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Butler ND, Kunjapur AM. Selective and Site-Specific Incorporation of Nonstandard Amino Acids Within Proteins for Therapeutic Applications. Methods Mol Biol 2024; 2720:35-53. [PMID: 37775656 DOI: 10.1007/978-1-0716-3469-1_3] [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: 10/01/2023]
Abstract
The incorporation of nonstandard amino acids (nsAAs) within protein sequences has broadened the chemical functionalities available for use in the study, prevention, or treatment of disease. The ability to genetically encode the introduction of nsAAs at precise sites of target recombinant proteins has enabled numerous applications such as bioorthogonal conjugation, thrombin inhibition, intrinsic biological containment of live organisms, and immunochemical termination of self-tolerance. Genetic systems that perform critical steps in enabling nsAA incorporation are known as orthogonal translation systems or orthogonal aminoacyl-tRNA synthetase/tRNA pairs. In Escherichia coli, several of these have been designed to accept novel nsAAs. Certain endogenous proteins, codon context, and standard amino acid concentrations can affect the yield of recombinant protein, the rate of nsAA incorporation within off-target proteins, and the rate of misincorporation due to near-cognate suppression or misacylation of orthogonal tRNA with standard amino acids. As a result, a significant body of work has been performed in engineering the E. coli genome to alleviate these issues. Here, we describe common methods applicable to nsAA incorporation within proteins in E. coli for sufficient purity and characterization for downstream therapeutic applications.
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Affiliation(s)
- Neil D Butler
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, USA
| | - Aditya M Kunjapur
- Department of Chemical and Biomolecular Engineering, University of Delaware, Newark, DE, USA.
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7
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Lahiri P, Martin MS, Lino BR, Scheck RA, Van Deventer JA. Dual Noncanonical Amino Acid Incorporation Enabling Chemoselective Protein Modification at Two Distinct Sites in Yeast. Biochemistry 2023; 62:2098-2114. [PMID: 37377426 PMCID: PMC11146674 DOI: 10.1021/acs.biochem.2c00711] [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] [Indexed: 06/29/2023]
Abstract
Incorporation of more than one noncanonical amino acid (ncAA) within a single protein endows the resulting construct with multiple useful features such as augmented molecular recognition or covalent cross-linking capabilities. Herein, for the first time, we demonstrate the incorporation of two chemically distinct ncAAs into proteins biosynthesized in Saccharomyces cerevisiae. To complement ncAA incorporation in response to the amber (TAG) stop codon in yeast, we evaluated opal (TGA) stop codon suppression using three distinct orthogonal translation systems. We observed selective TGA readthrough without detectable cross-reactivity from host translation components. Readthrough efficiency at TGA was modulated by factors including the local nucleotide environment, gene deletions related to the translation process, and the identity of the suppressor tRNA. These observations facilitated systematic investigation of dual ncAA incorporation in both intracellular and yeast-displayed protein constructs, where we observed efficiencies up to 6% of wild-type protein controls. The successful display of doubly substituted proteins enabled the exploration of two critical applications on the yeast surface─(A) antigen binding functionality and (B) chemoselective modification with two distinct chemical probes through sequential application of two bioorthogonal click chemistry reactions. Lastly, by utilizing a soluble form of a doubly substituted construct, we validated the dual incorporation system using mass spectrometry and demonstrated the feasibility of conducting selective labeling of the two ncAAs sequentially using a "single-pot" approach. Overall, our work facilitates the addition of a 22nd amino acid to the genetic code of yeast and expands the scope of applications of ncAAs for basic biological research and drug discovery.
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Affiliation(s)
- Priyanka Lahiri
- Chemical and Biological Engineering Department, Tufts University, Medford, MA 02155, USA
| | - Meghan S. Martin
- Chemistry Department, Tufts University, Medford, Massachusetts 02155, USA
| | - Briana R. Lino
- Chemical and Biological Engineering Department, Tufts University, Medford, MA 02155, USA
| | - Rebecca A. Scheck
- Chemistry Department, Tufts University, Medford, Massachusetts 02155, USA
| | - James A. Van Deventer
- Chemical and Biological Engineering Department, Tufts University, Medford, MA 02155, USA
- Biomedical Engineering Department, Tufts University, Medford, Massachusetts 02155, USA
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8
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Seki K, Galindo JL, Karim AS, Jewett MC. A Cell-Free Gene Expression Platform for Discovering and Characterizing Stop Codon Suppressing tRNAs. ACS Chem Biol 2023; 18:1324-1334. [PMID: 37257197 DOI: 10.1021/acschembio.3c00051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 06/02/2023]
Abstract
Non-canonical amino acids (ncAAs) can be incorporated into peptides and proteins to create new properties and functions. Site-specific ncAA incorporation is typically enabled by orthogonal translation systems comprising a stop codon suppressing tRNA (typically UAG), an aminoacyl-tRNA synthetase, and an ncAA of interest. Unfortunately, methods to discover and characterize suppressor tRNAs are limited because of laborious and time-consuming workflows in living cells. In this work, we develop anEscherichia coli crude extract-based cell-free gene expression system to rapidly express and characterize functional suppressor tRNAs. Our approach co-expresses orthogonal tRNAs using endogenous machinery alongside a stop-codon containing superfolder green fluorescent protein (sfGFP) reporter, which can be used as a simple read-out for suppression. As a model, we evaluate the UAG and UAA suppressing activity of several orthogonal tRNAs. Then, we demonstrate that co-transcription of two mutually orthogonal tRNAs can direct the incorporation of two unique ncAAs within a single modified sfGFP. Finally, we show that the cell-free workflow can be used to discover putative UAG-suppressor tRNAs found in metagenomic data, which are nonspecifically recognized by endogenous aminoacyl-tRNA synthetases. We anticipate that our cell-free system will accelerate the development of orthogonal translation systems for synthetic biology.
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Affiliation(s)
- Kosuke Seki
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Joey L Galindo
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Ashty S Karim
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
| | - Michael C Jewett
- Department of Chemical and Biological Engineering, Northwestern University, Evanston, Illinois 60208, United States
- Chemistry of Life Processes Institute, Northwestern University, Evanston, Illinois 60208, United States
- Center for Synthetic Biology, Northwestern University, Evanston, Illinois 60208, United States
- Robert H. Lurie Comprehensive Cancer Center and Simpson Querrey Institute, Northwestern University, Chicago, Illinois 60611, United States
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9
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Fatema N, Fan C. Studying lysine acetylation of citric acid cycle enzymes by genetic code expansion. Mol Microbiol 2023; 119:551-559. [PMID: 36890576 PMCID: PMC10636775 DOI: 10.1111/mmi.15052] [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: 02/03/2023] [Revised: 02/25/2023] [Accepted: 02/27/2023] [Indexed: 03/10/2023]
Abstract
Lysine acetylation is one of the most abundant post-translational modifications in nature, affecting many key biological pathways in both prokaryotes and eukaryotes. It has not been long since technological advances led to understanding of the roles of acetylation in biological processes. Most of those studies were based on proteomic analyses, which have identified thousands of acetylation sites in a wide range of proteins. However, the specific role of individual acetylation event remains largely unclear, mostly due to the existence of multiple acetylation and dynamic changes of acetylation levels. To solve these problems, the genetic code expansion technique has been applied in protein acetylation studies, facilitating the incorporation of acetyllysine into a specific lysine position to generate a site-specifically acetylated protein. By this method, the effects of acetylation at a specific lysine residue can be characterized with minimal interferences. Here, we summarized the development of the genetic code expansion technique for lysine acetylation and recent studies on lysine acetylation of citrate acid cycle enzymes in bacteria by this approach, providing a practical application of the genetic code expansion technique in protein acetylation studies.
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Affiliation(s)
- Nour Fatema
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, Arkansas, USA
| | - Chenguang Fan
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, Arkansas, USA
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, Arkansas, USA
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10
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Bednar RM, Karplus PA, Mehl RA. Site-specific dual encoding and labeling of proteins via genetic code expansion. Cell Chem Biol 2023; 30:343-361. [PMID: 36977415 PMCID: PMC10764108 DOI: 10.1016/j.chembiol.2023.03.004] [Citation(s) in RCA: 13] [Impact Index Per Article: 13.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/27/2022] [Revised: 02/10/2023] [Accepted: 03/03/2023] [Indexed: 03/29/2023]
Abstract
The ability to selectively modify proteins at two or more defined locations opens new avenues for manipulating, engineering, and studying living systems. As a chemical biology tool for the site-specific encoding of non-canonical amino acids into proteins in vivo, genetic code expansion (GCE) represents a powerful tool to achieve such modifications with minimal disruption to structure and function through a two-step "dual encoding and labeling" (DEAL) process. In this review, we summarize the state of the field of DEAL using GCE. In doing so, we describe the basic principles of GCE-based DEAL, catalog compatible encoding systems and reactions, explore demonstrated and potential applications, highlight emerging paradigms in DEAL methodologies, and propose novel solutions to current limitations.
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Affiliation(s)
- Riley M Bednar
- Department of Biochemistry and Biophysics, Oregon State University, 2011 Agricultural and Life Sciences Building, Corvallis, OR 97331-7305, USA; GCE4All Research Center, Oregon State University, 2011 Agricultural and Life Sciences, Corvallis, OR 97331-7305, USA
| | - P Andrew Karplus
- Department of Biochemistry and Biophysics, Oregon State University, 2011 Agricultural and Life Sciences Building, Corvallis, OR 97331-7305, USA; GCE4All Research Center, Oregon State University, 2011 Agricultural and Life Sciences, Corvallis, OR 97331-7305, USA
| | - Ryan A Mehl
- Department of Biochemistry and Biophysics, Oregon State University, 2011 Agricultural and Life Sciences Building, Corvallis, OR 97331-7305, USA; GCE4All Research Center, Oregon State University, 2011 Agricultural and Life Sciences, Corvallis, OR 97331-7305, USA.
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11
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Peng T, Das T, Ding K, Hang HC. Functional analysis of protein post-translational modifications using genetic codon expansion. Protein Sci 2023; 32:e4618. [PMID: 36883310 PMCID: PMC10031814 DOI: 10.1002/pro.4618] [Citation(s) in RCA: 10] [Impact Index Per Article: 10.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/05/2023] [Revised: 02/23/2023] [Accepted: 03/02/2023] [Indexed: 03/09/2023]
Abstract
Post-translational modifications (PTMs) of proteins not only exponentially increase the diversity of proteoforms, but also contribute to dynamically modulating the localization, stability, activity, and interaction of proteins. Understanding the biological consequences and functions of specific PTMs has been challenging for many reasons, including the dynamic nature of many PTMs and the technical limitations to access homogenously modified proteins. The genetic code expansion technology has emerged to provide unique approaches for studying PTMs. Through site-specific incorporation of unnatural amino acids (UAAs) bearing PTMs or their mimics into proteins, genetic code expansion allows the generation of homogenous proteins with site-specific modifications and atomic resolution both in vitro and in vivo. With this technology, various PTMs and mimics have been precisely introduced into proteins. In this review, we summarize the UAAs and approaches that have been recently developed to site-specifically install PTMs and their mimics into proteins for functional studies of PTMs.
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Affiliation(s)
- Tao Peng
- State Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate SchoolShenzhenChina
- Institute of Chemical Biology, Shenzhen Bay LaboratoryShenzhenChina
| | - Tandrila Das
- Departments of Immunology and Microbiology and ChemistryScripps ResearchLa JollaCaliforniaUSA
| | - Ke Ding
- State Key Laboratory of Chemical OncogenomicsSchool of Chemical Biology and Biotechnology, Peking University Shenzhen Graduate SchoolShenzhenChina
| | - Howard C. Hang
- Departments of Immunology and Microbiology and ChemistryScripps ResearchLa JollaCaliforniaUSA
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12
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Gong X, Zhang H, Shen Y, Fu X. Update of the Pyrrolysyl-tRNA Synthetase/tRNA Pyl Pair and Derivatives for Genetic Code Expansion. J Bacteriol 2023; 205:e0038522. [PMID: 36695595 PMCID: PMC9945579 DOI: 10.1128/jb.00385-22] [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] [Indexed: 01/26/2023] Open
Abstract
The cotranslational incorporation of pyrrolysine (Pyl), the 22nd proteinogenic amino acid, into proteins in response to the UAG stop codon represents an outstanding example of natural genetic code expansion. Genetic encoding of Pyl is conducted by the pyrrolysyl-tRNA synthetase (PylRS) and its cognate tRNA, tRNAPyl. Owing to the high tolerance of PylRS toward diverse amino acid substrates and great orthogonality in various model organisms, the PylRS/tRNAPyl-derived pairs are ideal for genetic code expansion to insert noncanonical amino acids (ncAAs) into proteins of interest. Since the discovery of cellular components involved in the biosynthesis and genetic encoding of Pyl, synthetic biologists have been enthusiastic about engineering PylRS/tRNAPyl-derived pairs to rewrite the genetic code of living cells. Recently, considerable progress has been made in understanding the molecular phylogeny, biochemical properties, and structural features of the PylRS/tRNAPyl pair, guiding its further engineering and optimization. In this review, we cover the basic and updated knowledge of the PylRS/tRNAPyl pair's unique characteristics that make it an outstanding tool for reprogramming the genetic code. In addition, we summarize the recent efforts to create efficient and (mutually) orthogonal PylRS/tRNAPyl-derived pairs for incorporation of diverse ncAAs by genome mining, rational design, and advanced directed evolution methods.
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Affiliation(s)
- Xuemei Gong
- College of Life Sciences, University of Chinese Academy of Sciences, Beijing, China
- BGI Research-Shenzhen, BGI, Shenzhen, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen, China
| | - Haolin Zhang
- BGI Research-Shenzhen, BGI, Shenzhen, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen, China
| | - Yue Shen
- BGI Research-Shenzhen, BGI, Shenzhen, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen, China
- BGI Research-Changzhou, BGI, Changzhou, China
| | - Xian Fu
- BGI Research-Shenzhen, BGI, Shenzhen, China
- Guangdong Provincial Key Laboratory of Genome Read and Write, Shenzhen, China
- BGI Research-Changzhou, BGI, Changzhou, China
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13
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Andrews J, Gan Q, Fan C. "Not-so-popular" orthogonal pairs in genetic code expansion. Protein Sci 2023; 32:e4559. [PMID: 36585833 PMCID: PMC9850438 DOI: 10.1002/pro.4559] [Citation(s) in RCA: 7] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/22/2022] [Revised: 12/16/2022] [Accepted: 12/29/2022] [Indexed: 01/01/2023]
Abstract
During the past decade, genetic code expansion has been proved to be a powerful tool for protein studies and engineering. As the key part, a series of orthogonal pairs have been developed to site-specifically incorporate hundreds of noncanonical amino acids (ncAAs) into proteins by using bacteria, yeast, mammalian cells, animals, or plants as hosts. Among them, the pair of tyrosyl-tRNA synthetase/tRNATyr from Methanococcus jannaschii and the pair of pyrrolysyl-tRNA synthetase/tRNAPyl from Methanosarcina species are the most popular ones. Recently, other "not-so-popular" orthogonal pairs have started to attract attentions, because they can provide more choices of ncAA candidates and are necessary for simultaneous incorporation of multiple ncAAs into a single protein. Here, we summarize the development and applications of those "not-so-popular" orthogonal pairs, providing guidance for studying and engineering proteins.
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Affiliation(s)
- Joseph Andrews
- Department of Chemistry and BiochemistryUniversity of ArkansasFayettevilleArkansasUSA
| | - Qinglei Gan
- Department of Chemistry and BiochemistryUniversity of ArkansasFayettevilleArkansasUSA
| | - Chenguang Fan
- Department of Chemistry and BiochemistryUniversity of ArkansasFayettevilleArkansasUSA
- Cell and Molecular Biology ProgramUniversity of ArkansasFayettevilleArkansasUSA
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14
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Morosky P, Comyns C, Nunes LGA, Chung CZ, Hoffmann PR, Söll D, Vargas-Rodriguez O, Krahn N. Dual incorporation of non-canonical amino acids enables production of post-translationally modified selenoproteins. Front Mol Biosci 2023; 10:1096261. [PMID: 36762212 PMCID: PMC9902344 DOI: 10.3389/fmolb.2023.1096261] [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: 11/11/2022] [Accepted: 01/11/2023] [Indexed: 01/25/2023] Open
Abstract
Post-translational modifications (PTMs) can occur on almost all amino acids in eukaryotes as a key mechanism for regulating protein function. The ability to study the role of these modifications in various biological processes requires techniques to modify proteins site-specifically. One strategy for this is genetic code expansion (GCE) in bacteria. The low frequency of post-translational modifications in bacteria makes it a preferred host to study whether the presence of a post-translational modification influences a protein's function. Genetic code expansion employs orthogonal translation systems engineered to incorporate a modified amino acid at a designated protein position. Selenoproteins, proteins containing selenocysteine, are also known to be post-translationally modified. Selenoproteins have essential roles in oxidative stress, immune response, cell maintenance, and skeletal muscle regeneration. Their complicated biosynthesis mechanism has been a hurdle in our understanding of selenoprotein functions. As technologies for selenocysteine insertion have recently improved, we wanted to create a genetic system that would allow the study of post-translational modifications in selenoproteins. By combining genetic code expansion techniques and selenocysteine insertion technologies, we were able to recode stop codons for insertion of N ε-acetyl-l-lysine and selenocysteine, respectively, into multiple proteins. The specificity of these amino acids for their assigned position and the simplicity of reverting the modified amino acid via mutagenesis of the codon sequence demonstrates the capacity of this method to study selenoproteins and the role of their post-translational modifications. Moreover, the evidence that Sec insertion technology can be combined with genetic code expansion tools further expands the chemical biology applications.
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Affiliation(s)
- Pearl Morosky
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Cody Comyns
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Lance G. A. Nunes
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| | - Christina Z. Chung
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Peter R. Hoffmann
- Department of Cell and Molecular Biology, John A. Burns School of Medicine, University of Hawaii, Honolulu, HI, United States
| | - Dieter Söll
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
- Department of Chemistry, Yale University, New Haven, CT, United States
| | - Oscar Vargas-Rodriguez
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Natalie Krahn
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
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15
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Shi N, Tong L, Lin H, Zheng Z, Zhang H, Dong L, Yang Y, Shen Y, Xia Q. Optimizing eRF1 to Enable the Genetic Encoding of Three Distinct Noncanonical Amino Acids in Mammalian Cells. Adv Biol (Weinh) 2022; 6:e2200092. [PMID: 35818694 DOI: 10.1002/adbi.202200092] [Citation(s) in RCA: 5] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/07/2022] [Revised: 06/06/2022] [Indexed: 01/28/2023]
Abstract
Site-specific incorporation of distinct noncanonical amino acids (ncAAs) into proteins via genetic code expansion in mammalian cells represents a new avenue for protein engineering. Reassigning three TAGs with the same ncAA in mammalian cells has previously been achieved using translational machinery. However, simultaneous recoding of three nonsense codons with distinct ncAAs in mammalian cells remains a challenge due to low incorporation efficiencies. Here, three optimized aaRS/tRNA pairs (i.e., the E. coli-derived tyrosyl (EcTyr)/tRNAUUA , E. coli-derived leucyl (EcLeu)/tRNACUA , and Methanosarcina mazei pyrrolysyl (MmPyl)/tRNAUCA pairs) are screened for ncAA incorporation. Furthermore, introduced combinations of eukaryotic release factor 1 (eRF1) mutants (E55R, E55D, N129D, and Y125F) significantly improve the encoding efficiency of the three premature stop codons' sites from 0.78% to 11.6%. Thus, site-specific incorporation of three distinct ncAAs into a single protein is achieved in this study. This work markedly expands the potential for multiple site-specific protein modifications within mammalian cells, thereby facilitating new in vivo applications.
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Affiliation(s)
- Ningning Shi
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Le Tong
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Haishuang Lin
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Zhetao Zheng
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Haoran Zhang
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Liangzhen Dong
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Yuelin Yang
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Yuxuan Shen
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
| | - Qing Xia
- State Key Laboratory of Natural and Biomimetic Drugs Department of Chemical Biology School of Pharmaceutical Sciences, Peking University, Beijing, 100191, China
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16
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Gueta O, Amiram M. Expanding the chemical repertoire of protein-based polymers for drug-delivery applications. Adv Drug Deliv Rev 2022; 190:114460. [PMID: 36030987 DOI: 10.1016/j.addr.2022.114460] [Citation(s) in RCA: 3] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/06/2022] [Accepted: 07/12/2022] [Indexed: 01/24/2023]
Abstract
Expanding the chemical repertoire of natural and artificial protein-based polymers (PBPs) can enable the production of sequence-defined, yet chemically diverse, biopolymers with customized or new properties that cannot be accessed in PBPs composed of only natural amino acids. Various approaches can enable the expansion of the chemical repertoire of PBPs, including chemical and enzymatic treatments or the incorporation of unnatural amino acids. These techniques are employed to install a wide variety of chemical groups-such as bio-orthogonally reactive, cross-linkable, post-translation modifications, and environmentally responsive groups-which, in turn, can facilitate the design of customized PBP-based drug-delivery systems with modified, fine-tuned, or entirely new properties and functions. Here, we detail the existing and emerging technologies for expanding the chemical repertoire of PBPs and review several chemical groups that either demonstrate or are anticipated to show potential in the design of PBP-based drug delivery systems. Finally, we provide our perspective on the remaining challenges and future directions in this field.
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Affiliation(s)
- Osher Gueta
- The Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 8410501, Israel
| | - Miriam Amiram
- The Avram and Stella Goldstein-Goren Department of Biotechnology Engineering, Ben-Gurion University of the Negev, P.O. Box 653, Beer-Sheva 8410501, Israel.
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17
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Wright DE, Siddika T, Heinemann IU, O’Donoghue P. Delivery of the selenoprotein thioredoxin reductase 1 to mammalian cells. Front Mol Biosci 2022; 9:1031756. [PMID: 36304926 PMCID: PMC9595596 DOI: 10.3389/fmolb.2022.1031756] [Citation(s) in RCA: 2] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/30/2022] [Accepted: 09/20/2022] [Indexed: 11/13/2022] Open
Abstract
Over-expression of genetically encoded thioredoxin reductase 1 (TrxR1) TrxR1 can be toxic to cells due to the formation of a truncated version of the enzyme. We developed a new mammalian cell-based model to investigate TrxR1 activity. Fusion of the HIV-derived cell penetrating peptide (TAT) enabled efficient cellular uptake of purified TrxR1 containing 21 genetically encoded amino acids, including selenocysteine. The TAT peptide did not significantly alter the catalytic activity of TrxR1 in vitro. We monitored TrxR1-dependent redox activity in human cells using a TrxR1-specific red fluorescent live-cell reporter. Using programmed selenocysteine incorporation in Escherichia coli, our approach allowed efficient production of active recombinant human selenoprotein TrxR1 for delivery to the homologous context of the mammalian cell. The delivered TAT-TrxR1 showed robust activity in live cells and provided a novel platform to study TrxR1 biology in human cells.
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18
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Stieglitz JT, Van Deventer JA. High-Throughput Aminoacyl-tRNA Synthetase Engineering for Genetic Code Expansion in Yeast. ACS Synth Biol 2022; 11:2284-2299. [PMID: 35793554 PMCID: PMC10065163 DOI: 10.1021/acssynbio.1c00626] [Citation(s) in RCA: 6] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Protein expression with genetically encoded noncanonical amino acids (ncAAs) benefits a broad range of applications, from the discovery of biological therapeutics to fundamental biological studies. A major factor limiting the use of ncAAs is the lack of orthogonal translation systems (OTSs) that support efficient genetic code expansion at repurposed stop codons. Aminoacyl-tRNA synthetases (aaRSs) have been extensively evolved in Escherichia coli but are not always orthogonal in eukaryotes. In this work, we use a yeast display-based ncAA incorporation reporter platform with fluorescence-activated cell sorting to screen libraries of aaRSs in high throughput for (1) the incorporation of ncAAs not previously encoded in yeast; (2) the improvement of the performance of an existing aaRS; (3) highly selective OTSs capable of discriminating between closely related ncAA analogues; and (4) OTSs exhibiting enhanced polyspecificity to support translation with structurally diverse sets of ncAAs. The number of previously undiscovered aaRS variants we report in this work more than doubles the total number of translationally active aaRSs available for genetic code manipulation in yeast. The success of myriad screening strategies has important implications related to the fundamental properties and evolvability of aaRSs. Furthermore, access to OTSs with diverse activities and specific or polyspecific properties is invaluable for a range of applications within chemical biology, synthetic biology, and protein engineering.
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Affiliation(s)
- Jessica T Stieglitz
- Chemical and Biological Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
| | - James A Van Deventer
- Chemical and Biological Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
- Biomedical Engineering Department, Tufts University, Medford, Massachusetts 02155, United States
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19
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Das PK, Sahoo A, Dasu VV. Current status, and the developments of hosts and expression systems for the production of recombinant human cytokines. Biotechnol Adv 2022; 59:107969. [PMID: 35525478 DOI: 10.1016/j.biotechadv.2022.107969] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/29/2021] [Revised: 04/28/2022] [Accepted: 04/29/2022] [Indexed: 02/07/2023]
Abstract
Cytokines consist of peptides, proteins and glycoproteins, which are biological signaling molecules, and boost cell-cell communication in immune reactions to stimulate cellular movements in the place of trauma, inflammation and infection. Recombinant cytokines are designed in such a way that they have generalized immunostimulation action or stimulate specific immune cells when the body encounters immunosuppressive signals from exogenous pathogens or other tumor microenvironments. Recombinant cytokines have improved the treatment processes for numerous diseases. They are also beneficial against novel toxicities that arise due to pharmacologic immunostimulators that lead to an imbalance in the regulation of cytokine. So, the production and use of recombinant human cytokines as therapeutic proteins are significant for medical treatment purposes. For the improved production of recombinant human cytokines, the development of host cells such as bacteria, yeast, fungi, insect, mammal and transgenic plants, and the specific expression systems for individual hosts is necessary. The recent advancements in the field of genetic engineering are beneficial for easy and efficient genetic manipulations for hosts as well as expression cassettes. The use of metabolic engineering and systems biology approaches have tremendous applications in recombinant protein production by generating mathematical models, and analyzing complex biological networks and metabolic pathways via simulations to understand the interconnections between metabolites and genetic behaviors. Further, the bioprocess developments and the optimization of cell culture conditions would enhance recombinant cytokines productivity on large scales.
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Affiliation(s)
- Prabir Kumar Das
- Biochemical Engineering Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Ansuman Sahoo
- Biochemical Engineering Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India
| | - Veeranki Venkata Dasu
- Biochemical Engineering Laboratory, Department of Biosciences and Bioengineering, Indian Institute of Technology Guwahati, Guwahati 781039, Assam, India.
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20
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Qin X, Liu T. Recent Advances in Genetic Code Expansion Techniques for Protein Phosphorylation Studies. J Mol Biol 2021; 434:167406. [PMID: 34929199 DOI: 10.1016/j.jmb.2021.167406] [Citation(s) in RCA: 10] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/03/2021] [Revised: 12/03/2021] [Accepted: 12/10/2021] [Indexed: 12/22/2022]
Abstract
Protein phosphorylation is a reversible, residue-specific posttranslational modification that plays a pivotal role in cell signaling, and the phosphorylation state of proteins is tightly regulated by kinases and phosphatases. Malfunction of this regulation is often associated with human diseases, and therefore elucidation of the function and regulation of this posttranslational modification is important. Genetic code expansion, which allows for site-specific introduction of noncanonical amino acids directly into target proteins in response to a non-sense codon is a powerful method for preparing homogeneously phosphorylated proteins both in Escherichia coli and mammalian cells and therefore is useful for studying protein phosphorylation. Herein, we summarize recent developments in the application of genetic code expansion for protein phosphorylation studies.
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Affiliation(s)
- Xuewen Qin
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China
| | - Tao Liu
- State Key Laboratory of Natural and Biomimetic Drugs, Department of Molecular and Cellular Pharmacology, School of Pharmaceutical Sciences, Peking University, 38 Xueyuan Road, Haidian District, Beijing 100191, China.
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21
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Liu M, Guo L, Fu Y, Huo M, Qi Q, Zhao G. Bacterial protein acetylation and its role in cellular physiology and metabolic regulation. Biotechnol Adv 2021; 53:107842. [PMID: 34624455 DOI: 10.1016/j.biotechadv.2021.107842] [Citation(s) in RCA: 21] [Impact Index Per Article: 7.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/24/2021] [Revised: 09/22/2021] [Accepted: 10/03/2021] [Indexed: 12/28/2022]
Abstract
Protein acetylation is an evolutionarily conserved posttranslational modification. It affects enzyme activity, metabolic flux distribution, and other critical physiological and biochemical processes by altering protein size and charge. Protein acetylation may thus be a promising tool for metabolic regulation to improve target production and conversion efficiency in fermentation. Here we review the role of protein acetylation in bacterial physiology and metabolism and describe applications of protein acetylation in fermentation engineering and strategies for regulating acetylation status. Although protein acetylation has become a hot topic, the regulatory mechanisms have not been fully characterized. We propose future research directions in protein acetylation.
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Affiliation(s)
- Min Liu
- State Key Laboratory of Microbial Technology, Shandong University, 266237 Qingdao, China; CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China
| | - Likun Guo
- State Key Laboratory of Microbial Technology, Shandong University, 266237 Qingdao, China
| | - Yingxin Fu
- State Key Laboratory of Microbial Technology, Shandong University, 266237 Qingdao, China
| | - Meitong Huo
- State Key Laboratory of Microbial Technology, Shandong University, 266237 Qingdao, China
| | - Qingsheng Qi
- State Key Laboratory of Microbial Technology, Shandong University, 266237 Qingdao, China
| | - Guang Zhao
- State Key Laboratory of Microbial Technology, Shandong University, 266237 Qingdao, China; CAS Key Laboratory of Biobased Materials, Qingdao Institute of Bioenergy and Bioprocess Technology, Chinese Academy of Sciences, Qingdao, 266101, China.
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22
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Giannakoulias S, Shringari SR, Ferrie JJ, Petersson EJ. Biomolecular simulation based machine learning models accurately predict sites of tolerability to the unnatural amino acid acridonylalanine. Sci Rep 2021; 11:18406. [PMID: 34526629 PMCID: PMC8443755 DOI: 10.1038/s41598-021-97965-2] [Citation(s) in RCA: 4] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/06/2021] [Accepted: 08/17/2021] [Indexed: 11/08/2022] Open
Abstract
The incorporation of unnatural amino acids (Uaas) has provided an avenue for novel chemistries to be explored in biological systems. However, the successful application of Uaas is often hampered by site-specific impacts on protein yield and solubility. Although previous efforts to identify features which accurately capture these site-specific effects have been unsuccessful, we have developed a set of novel Rosetta Custom Score Functions and alternative Empirical Score Functions that accurately predict the effects of acridon-2-yl-alanine (Acd) incorporation on protein yield and solubility. Acd-containing mutants were simulated in PyRosetta, and machine learning (ML) was performed using either the decomposed values of the Rosetta energy function, or changes in residue contacts and bioinformatics. Using these feature sets, which represent Rosetta score function specific and bioinformatics-derived terms, ML models were trained to predict highly abstract experimental parameters such as mutant protein yield and solubility and displayed robust performance on well-balanced holdouts. Model feature importance analyses demonstrated that terms corresponding to hydrophobic interactions, desolvation, and amino acid angle preferences played a pivotal role in predicting tolerance of mutation to Acd. Overall, this work provides evidence that the application of ML to features extracted from simulated structural models allow for the accurate prediction of diverse and abstract biological phenomena, beyond the predictivity of traditional modeling and simulation approaches.
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Affiliation(s)
- Sam Giannakoulias
- Department of Chemistry, University of Pennsylvania, 231 S. 34th St, Philadelphia, PA, 19104, USA
| | - Sumant R Shringari
- Department of Chemistry, University of Pennsylvania, 231 S. 34th St, Philadelphia, PA, 19104, USA
| | - John J Ferrie
- Department of Molecular & Cell Biology, University of California, Berkeley, 475B Li Ka Shing Center, Berkeley, CA, 94720, USA.
| | - E James Petersson
- Department of Chemistry, University of Pennsylvania, 231 S. 34th St, Philadelphia, PA, 19104, USA.
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23
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Dunkelmann DL, Oehm SB, Beattie AT, Chin JW. A 68-codon genetic code to incorporate four distinct non-canonical amino acids enabled by automated orthogonal mRNA design. Nat Chem 2021; 13:1110-1117. [PMID: 34426682 DOI: 10.1038/s41557-021-00764-5] [Citation(s) in RCA: 15] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/02/2021] [Accepted: 06/30/2021] [Indexed: 12/15/2022]
Abstract
Orthogonal (O) ribosome-mediated translation of O-mRNAs enables the incorporation of up to three distinct non-canonical amino acids (ncAAs) into proteins in Escherichia coli (E. coli). However, the general and efficient incorporation of multiple distinct ncAAs by O-ribosomes requires scalable strategies for both creating efficiently and specifically translated O-mRNAs, and the compact expression of multiple O-aminoacyl-tRNA synthetase (O-aaRS)/O-tRNA pairs. We automate the discovery of O-mRNAs that lead to up to 40 times more protein, and are up to 50-fold more orthogonal, than previous O-mRNAs; protein yields from our O-mRNAs match or exceed those from wild-type mRNAs. These advances enable a 33-fold increase in yield for incorporating three distinct ncAAs. We automate the creation of operons for O-tRNA genes, and develop operons for O-aaRS genes. Combining our advances creates a 68-codon, 24-amino-acid genetic code to efficiently incorporate four distinct ncAAs into a single protein in response to four distinct quadruplet codons.
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Affiliation(s)
| | - Sebastian B Oehm
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Adam T Beattie
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK
| | - Jason W Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
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24
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Chen H, Wilson J, Ottinger S, Gan Q, Fan C. Introducing noncanonical amino acids for studying and engineering bacterial microcompartments. Curr Opin Microbiol 2021; 61:67-72. [PMID: 33813159 PMCID: PMC8169543 DOI: 10.1016/j.mib.2021.03.004] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/05/2020] [Revised: 02/28/2021] [Accepted: 03/11/2021] [Indexed: 10/21/2022]
Abstract
Bacterial microcompartments (BMCs) with selectively permeable shells and encapsulated enzyme cores are well-suited candidates for nano-bioreactors because of their advantages of enhancing pathway flux and protection against toxic products. To better study and engineer protein-based BMCs, a series of protein chemistry approaches are adopted. As one of the most advanced techniques, genetic code expansion can introduce various noncanonical amino acids (ncAAs) with diverse functional groups into target proteins, thus providing powerful tools for protein studies and engineering. This review summarizes and proposes useful tools based on current development of the genetic code expansion technique towards challenges in BMC studies and engineering.
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Affiliation(s)
- Hao Chen
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, USA
| | - Jessica Wilson
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, USA
| | - Sara Ottinger
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, USA
| | - Qinglei Gan
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, USA
| | - Chenguang Fan
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, USA; Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, USA.
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25
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Tharp JM, Vargas-Rodriguez O, Schepartz A, Söll D. Genetic Encoding of Three Distinct Noncanonical Amino Acids Using Reprogrammed Initiator and Nonsense Codons. ACS Chem Biol 2021; 16:766-774. [PMID: 33723984 DOI: 10.1021/acschembio.1c00120] [Citation(s) in RCA: 37] [Impact Index Per Article: 12.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/03/2023]
Abstract
We recently described an orthogonal initiator tRNA (itRNATy2) that can initiate protein synthesis with noncanonical amino acids (ncAAs) in response to the UAG nonsense codon. Here, we report that a mutant of itRNATy2 (itRNATy2AUA) can efficiently initiate translation in response to the UAU tyrosine codon, giving rise to proteins with an ncAA at their N-terminus. We show that, in cells expressing itRNATy2AUA, UAU can function as a dual-use codon that selectively encodes ncAAs at the initiating position and predominantly tyrosine at elongating positions. Using itRNATy2AUA, in conjunction with its cognate tyrosyl-tRNA synthetase and two mutually orthogonal pyrrolysyl-tRNA synthetases, we demonstrate that UAU can be reassigned along with UAG or UAA to encode two distinct ncAAs in the same protein. Furthermore, by engineering the substrate specificity of one of the pyrrolysyl-tRNA synthetases, we developed a triply orthogonal system that enables simultaneous reassignment of UAU, UAG, and UAA to produce proteins containing three distinct ncAAs at precisely defined sites. To showcase the utility of this system, we produced proteins containing two or three ncAAs, with unique bioorthogonal functional groups, and demonstrate that these proteins can be separately modified with multiple fluorescent probes.
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26
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Liu Y, Davis RG, Thomas PM, Kelleher NL, Jewett MC. In vitro-Constructed Ribosomes Enable Multi-site Incorporation of Noncanonical Amino Acids into Proteins. Biochemistry 2021; 60:161-169. [PMID: 33426883 DOI: 10.1021/acs.biochem.0c00829] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/07/2023]
Abstract
Efforts to expand the scope of ribosome-mediated polymerization to incorporate noncanonical amino acids (ncAAs) into peptides and proteins hold promise for creating new classes of enzymes, therapeutics, and materials. Recently, the integrated synthesis, assembly, and translation (iSAT) system was established to construct functional ribosomes in cell-free systems. However, the iSAT system has not been shown to be compatible with genetic code expansion. Here, to address this gap, we develop an iSAT platform capable of manufacturing pure proteins with site-specifically incorporated ncAAs. We first establish an iSAT platform based on extracts from genomically recoded Escherichia coli lacking release factor 1 (RF-1). This permits complete reassignment of the amber codon translation function. Next, we optimize orthogonal translation system components to demonstrate the benefits of genomic RF-1 deletion on incorporation of ncAAs into proteins. Using our optimized platform, we demonstrate high-level, multi-site incorporation of p-acetyl-phenylalanine (pAcF) and p-azido-phenylalanine into superfolder green fluorescent protein (sfGFP). Mass spectrometry analysis confirms the high accuracy of incorporation for pAcF at one, two, and five amber sites in sfGFP. The iSAT system updated for ncAA incorporation sets the stage for investigating ribosomal mutations to better understand the fundamental basis of protein synthesis, manufacturing proteins with new properties, and engineering ribosomes for novel polymerization chemistries.
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27
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Abstract
The encoded biosynthesis of proteins provides the ultimate paradigm for high-fidelity synthesis of long polymers of defined sequence and composition, but it is limited to polymerizing the canonical amino acids. Recent advances have built on genetic code expansion - which commonly permits the cellular incorporation of one type of non-canonical amino acid into a protein - to enable the encoded incorporation of several distinct non-canonical amino acids. Developments include strategies to read quadruplet codons, use non-natural DNA base pairs, synthesize completely recoded genomes and create orthogonal translational components with reprogrammed specificities. These advances may enable the genetically encoded synthesis of non-canonical biopolymers and provide a platform for transforming the discovery and evolution of new materials and therapeutics.
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Affiliation(s)
| | - Jason W Chin
- Medical Research Council Laboratory of Molecular Biology, Cambridge, UK.
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28
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Galindo Casas M, Stargardt P, Mairhofer J, Wiltschi B. Decoupling Protein Production from Cell Growth Enhances the Site-Specific Incorporation of Noncanonical Amino Acids in E. coli. ACS Synth Biol 2020; 9:3052-3066. [PMID: 33150786 DOI: 10.1021/acssynbio.0c00298] [Citation(s) in RCA: 12] [Impact Index Per Article: 3.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/11/2022]
Abstract
The site-specific incorporation of noncanonical amino acids (ncAAs) into proteins by amber stop codon suppression has become a routine method in academic laboratories. This approach requires an amber suppressor tRNACUA to read the amber codon and an aminoacyl-tRNA synthetase to charge the tRNACUA with the ncAA. However, a major drawback is the low yield of the mutant protein in comparison to the wild type. This effect primarily results from the competition of release factor 1 with the charged suppressor tRNACUA for the amber codon at the A-site of the ribosome. A number of laboratories have attempted to improve the incorporation efficiency of ncAAs with moderate results. We aimed at increasing the efficiency to produce high yields of ncAA-functionalized proteins in a scalable setting for industrial application. To do this, we inserted an ncAA into the enhanced green fluorescent protein and an antibody mimetic molecule using an industrial E. coli strain, which produces recombinant proteins independent of cell growth. The controlled decoupling of recombinant protein production from cell growth considerably increased the incorporation of the ncAA, producing substantially higher protein yields versus the reference E. coli strain BL21(DE3). The target proteins were expressed at high levels, and the ncAA was efficiently incorporated with excellent fidelity while the protein function was preserved.
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Affiliation(s)
- Meritxell Galindo Casas
- acib − Austrian Center of Industrial Biotechnology, 8010 Graz, Austria
- Institute of Molecular Biotechnology, Graz University of Technology, 8010 Graz, Austria
| | | | | | - Birgit Wiltschi
- acib − Austrian Center of Industrial Biotechnology, 8010 Graz, Austria
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29
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Cui Z, Johnston WA, Alexandrov K. Cell-Free Approach for Non-canonical Amino Acids Incorporation Into Polypeptides. Front Bioeng Biotechnol 2020; 8:1031. [PMID: 33117774 PMCID: PMC7550873 DOI: 10.3389/fbioe.2020.01031] [Citation(s) in RCA: 23] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/19/2020] [Accepted: 08/07/2020] [Indexed: 12/12/2022] Open
Abstract
Synthetic biology holds promise to revolutionize the life sciences and biomedicine via expansion of macromolecular diversity outside the natural chemical space. Use of non-canonical amino acids (ncAAs) via codon reassignment has found diverse applications in protein structure and interaction analysis, introduction of post-translational modifications, production of constrained peptides, antibody-drug conjugates, and novel enzymes. However, simultaneously encoding multiple ncAAs in vivo requires complex engineering and is sometimes restricted by the cell's poor uptake of ncAAs. In contrast the open nature of cell-free protein synthesis systems offers much greater freedom for manipulation and repurposing of the biosynthetic machinery by controlling the level and identity of translational components and reagents, and allows simultaneous incorporation of multiple ncAAs with non-canonical side chains and even backbones (N-methyl, D-, β-amino acids, α-hydroxy acids etc.). This review focuses on the two most used Escherichia coli-based cell-free protein synthesis systems; cell extract- and PURE-based systems. The former is a biological mixture with >500 proteins, while the latter consists of 38 individually purified biomolecules. We delineate compositions of these two systems and discuss their respective advantages and applications. Also, we dissect the translational components required for ncAA incorporation and compile lists of ncAAs that can be incorporated into polypeptides via different acylation approaches. We highlight the recent progress in using unnatural nucleobase pairs to increase the repertoire of orthogonal codons, as well as using tRNA-specific ribozymes for in situ acylation. We summarize advances in engineering of translational machinery such as tRNAs, aminoacyl-tRNA synthetases, elongation factors, and ribosomes to achieve efficient incorporation of structurally challenging ncAAs. We note that, many engineered components of biosynthetic machinery are developed for the use in vivo but are equally applicable to the in vitro systems. These are included in the review to provide a comprehensive overview for ncAA incorporation and offer new insights for the future development in cell-free systems. Finally, we highlight the exciting progress in the genomic engineering, resulting in E. coli strains free of amber and some redundant sense codons. These strains can be used for preparation of cell extracts offering multiple reassignment options.
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Affiliation(s)
- Zhenling Cui
- Synthetic Biology Laboratory, School of Biology and Environmental Science, Queensland University of Technology, Brisbane, QLD, Australia
| | - Wayne A Johnston
- Synthetic Biology Laboratory, School of Biology and Environmental Science, Queensland University of Technology, Brisbane, QLD, Australia
| | - Kirill Alexandrov
- Synthetic Biology Laboratory, School of Biology and Environmental Science, Queensland University of Technology, Brisbane, QLD, Australia
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30
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Abstract
Within the broad field of synthetic biology, genetic code expansion (GCE) techniques enable creation of proteins with an expanded set of amino acids. This may be invaluable for applications in therapeutics, bioremediation, and biocatalysis. Central to GCE are aminoacyl-tRNA synthetases (aaRSs) as they link a non-canonical amino acid (ncAA) to their cognate tRNA, allowing ncAA incorporation into proteins on the ribosome. The ncAA-acylating aaRSs and their tRNAs should not cross-react with 20 natural aaRSs and tRNAs in the host, i.e., they need to function as an orthogonal translating system. All current orthogonal aaRS•tRNA pairs have been engineered from naturally occurring molecules to change the aaRS's amino acid specificity or assign the tRNA to a liberated codon of choice. Here we discuss the importance of orthogonality in GCE, laboratory techniques employed to create designer aaRSs and tRNAs, and provide an overview of orthogonal aaRS•tRNA pairs for GCE purposes.
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Affiliation(s)
- Natalie Krahn
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Jeffery M Tharp
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Ana Crnković
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States
| | - Dieter Söll
- Department of Molecular Biophysics and Biochemistry, Yale University, New Haven, CT, United States.
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31
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Unremitting progresses for phosphoprotein synthesis. Curr Opin Chem Biol 2020; 58:96-111. [PMID: 32889414 DOI: 10.1016/j.cbpa.2020.07.009] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/31/2020] [Revised: 07/16/2020] [Accepted: 07/21/2020] [Indexed: 02/03/2023]
Abstract
Phosphorylation, one of the important protein post-translational modifications, is involved in many essential cellular processes. Site-specifical and homogeneous phosphoproteins can be used as probes for elucidating the protein phosphorylation network and as potential therapeutics for interfering their involved biological events. However, the generation of phosphoproteins has been challenging owing to the limitation of chemical synthesis and protein expression systems. Despite the pioneering discoveries in phosphoprotein synthesis, over the past decade, great progresses in this field have also been made to promote the biofunctional exploration of protein phosphorylation largely. Therefore, in this review, we mainly summarize recent advances in phosphoprotein synthesis, which includes five sections: 1) synthesis of the nonhydrolyzable phosphorylated amino acid mimetic building blocks, 2) chemical total and semisynthesis strategy, 3) in-cell and in vitro genetic code expansion strategy, 4) the late-stage modification strategy, 5) nonoxygen phosphoprotein synthesis.
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32
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Wu Y, Wang Z, Qiao X, Li J, Shu X, Qi H. Emerging Methods for Efficient and Extensive Incorporation of Non-canonical Amino Acids Using Cell-Free Systems. Front Bioeng Biotechnol 2020; 8:863. [PMID: 32793583 PMCID: PMC7387428 DOI: 10.3389/fbioe.2020.00863] [Citation(s) in RCA: 13] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/27/2020] [Accepted: 07/06/2020] [Indexed: 12/17/2022] Open
Abstract
Cell-free protein synthesis (CFPS) has emerged as a novel protein expression platform. Especially the incorporation of non-canonical amino acids (ncAAs) has led to the development of numerous flexible methods for efficient and extensive expression of artificial proteins. Approaches were developed to eliminate the endogenous competition for ncAAs and engineer translation factors, which significantly enhanced the incorporation efficiency. Furthermore, in vitro aminoacylation methods can be conveniently combined with cell-free systems, extensively expanding the available ncAAs with novel and unique moieties. In this review, we summarize the recent progresses on the efficient and extensive incorporation of ncAAs by different strategies based on the elimination of competition by endogenous factors, translation factors engineering and extensive incorporation of novel ncAAs coupled with in vitro aminoacylation methods in CFPS. We also aim to offer new ideas to researchers working on ncAA incorporation techniques in CFPS and applications in various emerging fields.
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Affiliation(s)
- Yang Wu
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin, China
| | - Zhaoguan Wang
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin, China
| | - Xin Qiao
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin, China
| | - Jiaojiao Li
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin, China
| | - Xiangrong Shu
- Department of Pharmacy, Tianjin Huanhu Hospital, Tianjin, China
| | - Hao Qi
- School of Chemical Engineering and Technology, Tianjin University, Tianjin, China.,Key Laboratory of Systems Bioengineering, Ministry of Education, Tianjin University, Tianjin, China
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33
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Shi Y, Zhang Y, Lin S, Wang C, Zhou J, Peng D, Xue Y. dbPSP 2.0, an updated database of protein phosphorylation sites in prokaryotes. Sci Data 2020; 7:164. [PMID: 32472030 PMCID: PMC7260176 DOI: 10.1038/s41597-020-0506-7] [Citation(s) in RCA: 11] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/02/2020] [Accepted: 04/30/2020] [Indexed: 12/20/2022] Open
Abstract
In prokaryotes, protein phosphorylation plays a critical role in regulating a broad spectrum of biological processes and occurs mainly on various amino acids, including serine (S), threonine (T), tyrosine (Y), arginine (R), aspartic acid (D), histidine (H) and cysteine (C) residues of protein substrates. Through literature curation and public database integration, here we reported an updated database of phosphorylation sites (p-sites) in prokaryotes (dbPSP 2.0) that contains 19,296 experimentally identified p-sites in 8,586 proteins from 200 prokaryotic organisms, which belong to 12 phyla of two kingdoms, bacteria and archaea. To carefully annotate these phosphoproteins and p-sites, we integrated the knowledge from 88 publicly available resources that covers 9 aspects, namely, taxonomy annotation, genome annotation, function annotation, transcriptional regulation, sequence and structure information, family and domain annotation, interaction, orthologous information and biological pathway. In contrast to version 1.0 (~30 MB), dbPSP 2.0 contains ~9 GB of data, with a 300-fold increased volume. We anticipate that dbPSP 2.0 can serve as a useful data resource for further investigating phosphorylation events in prokaryotes. dbPSP 2.0 is free for all users to access at: http://dbpsp.biocuckoo.cn.
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Affiliation(s)
- Ying Shi
- Key Laboratory of Molecular Biophysics of Ministry of Education, Hubei Bioinformatics and Molecular Imaging Key Laboratory, Center for Artificial Intelligence Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China
| | - Ying Zhang
- Key Laboratory of Molecular Biophysics of Ministry of Education, Hubei Bioinformatics and Molecular Imaging Key Laboratory, Center for Artificial Intelligence Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China
| | - Shaofeng Lin
- Key Laboratory of Molecular Biophysics of Ministry of Education, Hubei Bioinformatics and Molecular Imaging Key Laboratory, Center for Artificial Intelligence Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China
| | - Chenwei Wang
- Key Laboratory of Molecular Biophysics of Ministry of Education, Hubei Bioinformatics and Molecular Imaging Key Laboratory, Center for Artificial Intelligence Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China
| | - Jiaqi Zhou
- Key Laboratory of Molecular Biophysics of Ministry of Education, Hubei Bioinformatics and Molecular Imaging Key Laboratory, Center for Artificial Intelligence Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China
| | - Di Peng
- Key Laboratory of Molecular Biophysics of Ministry of Education, Hubei Bioinformatics and Molecular Imaging Key Laboratory, Center for Artificial Intelligence Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China.
| | - Yu Xue
- Key Laboratory of Molecular Biophysics of Ministry of Education, Hubei Bioinformatics and Molecular Imaging Key Laboratory, Center for Artificial Intelligence Biology, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, Hubei, 430074, China.
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34
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Xiao Q, Liu Z, Zhao X, Xiong H. Multiple Site-Specific One-Pot Synthesis of Two Proteins by the Bio-Orthogonal Flexizyme System. Front Bioeng Biotechnol 2020; 8:37. [PMID: 32117920 PMCID: PMC7010957 DOI: 10.3389/fbioe.2020.00037] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 11/11/2019] [Accepted: 01/15/2020] [Indexed: 11/29/2022] Open
Abstract
Lysine acetylation is a reversible post-translational modification (PTM) vastly employed in many biological events, including regulating gene expression and dynamic transitions in chromatin remodeling. We have developed the first one-pot bio-orthogonal flexizyme system in which both acetyl-lysine (AcK) and non-hydrolysable thioacetyl-lysine (ThioAcK) were site-specifically incorporated into human histone H3 and H4 at different lysine positions in vitro, either individually or in pairs. In addition, the high accuracy of this system moving toward one-pot synthesis of desired histone variants is also reported.
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Affiliation(s)
- Qiuyun Xiao
- Institute for Advanced Study, Shenzhen University, Shenzhen, China.,Key Laboratory of Optoelectronic Devices and Systems of Ministry of Education and Guangdong Province, College of Optoelectronic Engineering, Shenzhen University, Shenzhen, China
| | - Zihan Liu
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Xuan Zhao
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
| | - Hai Xiong
- Institute for Advanced Study, Shenzhen University, Shenzhen, China
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35
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Zhu P, Gafken PR, Mehl RA, Cooley RB. A Highly Versatile Expression System for the Production of Multiply Phosphorylated Proteins. ACS Chem Biol 2019; 14:1564-1572. [PMID: 31243963 DOI: 10.1021/acschembio.9b00307] [Citation(s) in RCA: 32] [Impact Index Per Article: 6.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/06/2023]
Abstract
Genetic Code Expansion (GCE) can use TAG stop codons to guide site-specific incorporation of phosphoserine (pSer) into proteins. To eliminate prematurely truncated peptides, improve yields, and enhance the production of multiphosphorylated proteins, Release Factor 1 (RF1)-deficient expression hosts were developed, yet these grew slowly and their use was associated with extensive misincorporation of natural amino acids instead of pSer. Here, we merge a healthy RF1-deficient E. coli cell line with a high-efficiency pSer GCE translation system to produce a versatile pSer GCE platform in which only trace misincorporation of natural amino acids is detected even when five phosphoserines were introduced into one protein. Approximately 400 and 200 mg of singly and doubly phosphorylated GFP per liter of culture were obtained. Importantly, the lack of truncated protein permits expression of oligomeric proteins and the use of N-terminal solubility-enhancing proteins to aid phospho-protein expression and purification. To illustrate the enhanced utility of this system, we produce doubly phosphorylated STING (Stimulator of Interferon Genes), as well as triply phosphorylated BAD (Bcl2-associated agonist of cell death) complexed with 14-3-3, in quantity, purity, and homogeneity sufficient for structural biology applications. We anticipate that the facile access to phosphoproteins enabled by this system, which we call pSer-3.1G, will expand studies of the phospho-proteome.
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Affiliation(s)
- Phillip Zhu
- Oregon State University, Department of Biochemistry and Biophysics, 2011 Agricultural and Life Sciences, Corvallis, Oregon 97331, United States
| | - Philip R. Gafken
- Proteomics Shared Resource, Fred Hutchinson Cancer Research Center, Seattle, Washington 98109, United States
| | - Ryan A. Mehl
- Oregon State University, Department of Biochemistry and Biophysics, 2011 Agricultural and Life Sciences, Corvallis, Oregon 97331, United States
| | - Richard B. Cooley
- Oregon State University, Department of Biochemistry and Biophysics, 2011 Agricultural and Life Sciences, Corvallis, Oregon 97331, United States
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36
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Smolskaya S, Andreev YA. Site-Specific Incorporation of Unnatural Amino Acids into Escherichia coli Recombinant Protein: Methodology Development and Recent Achievement. Biomolecules 2019; 9:biom9070255. [PMID: 31261745 PMCID: PMC6681230 DOI: 10.3390/biom9070255] [Citation(s) in RCA: 43] [Impact Index Per Article: 8.6] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2019] [Revised: 06/21/2019] [Accepted: 06/25/2019] [Indexed: 12/13/2022] Open
Abstract
More than two decades ago a general method to genetically encode noncanonical or unnatural amino acids (NAAs) with diverse physical, chemical, or biological properties in bacteria, yeast, animals and mammalian cells was developed. More than 200 NAAs have been incorporated into recombinant proteins by means of non-endogenous aminoacyl-tRNA synthetase (aa-RS)/tRNA pair, an orthogonal pair, that directs site-specific incorporation of NAA encoded by a unique codon. The most established method to genetically encode NAAs in Escherichia coli is based on the usage of the desired mutant of Methanocaldococcus janaschii tyrosyl-tRNA synthetase (MjTyrRS) and cognate suppressor tRNA. The amber codon, the least-used stop codon in E. coli, assigns NAA. Until very recently the genetic code expansion technology suffered from a low yield of targeted proteins due to both incompatibilities of orthogonal pair with host cell translational machinery and the competition of suppressor tRNA with release factor (RF) for binding to nonsense codons. Here we describe the latest progress made to enhance nonsense suppression in E. coli with the emphasis on the improved expression vectors encoding for an orthogonal aa-RA/tRNA pair, enhancement of aa-RS and suppressor tRNA efficiency, the evolution of orthogonal EF-Tu and attempts to reduce the effect of RF1.
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Affiliation(s)
- Sviatlana Smolskaya
- Sechenov First Moscow State Medical University, Institute of Molecular Medicine, Trubetskaya str. 8, bld. 2, 119991 Moscow, Russia.
| | - Yaroslav A Andreev
- Sechenov First Moscow State Medical University, Institute of Molecular Medicine, Trubetskaya str. 8, bld. 2, 119991 Moscow, Russia.
- Shemyakin-Ovchinnikov Institute of Bioorganic Chemistry, Russian Academy of Sciences, ul. Miklukho-Maklaya 16/10, 117997 Moscow, Russia.
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37
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Venkat S, Chen H, McGuire P, Stahman A, Gan Q, Fan C. Characterizing lysine acetylation of Escherichia coli type II citrate synthase. FEBS J 2019; 286:2799-2808. [PMID: 30974512 DOI: 10.1111/febs.14845] [Citation(s) in RCA: 14] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/01/2019] [Revised: 03/19/2019] [Accepted: 04/09/2019] [Indexed: 11/27/2022]
Abstract
The citrate synthase (CS) catalyzes the first reaction of the tricarboxylic acid cycle, playing an important role in central metabolism. The acetylation of lysine residues in the Escherichia coli Type II CS has been identified at multiple sites by proteomic studies, but their effects remain unknown. In this study, we applied the genetic code expansion strategy to generate 10 site-specifically acetylated CS variants which have been identified in nature. Enzyme assays and kinetic analyses showed that lysine acetylation could decrease the overall CS enzyme activity, largely due to the acetylation of K295 which impaired the binding of acetyl-coenzyme A. Further genetic studies as well as in vitro acetylation and deacetylation assays were performed to explore the acetylation and deacetylation processes of the CS, which indicated that the CS could be acetylated by acetyl-phosphate chemically, and be deacetylated by the CobB deacetylase.
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Affiliation(s)
- Sumana Venkat
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, USA
| | - Hao Chen
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, USA
| | - Paige McGuire
- Department of Biological Sciences, University of Arkansas, Fayetteville, AR, USA
| | - Alleigh Stahman
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, USA
| | - Qinglei Gan
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, USA
| | - Chenguang Fan
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, USA.,Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, USA
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38
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Venkat S, Chen H, Gan Q, Fan C. The Application of Cell-Free Protein Synthesis in Genetic Code Expansion for Post-translational Modifications. Front Pharmacol 2019; 10:248. [PMID: 30949051 PMCID: PMC6436179 DOI: 10.3389/fphar.2019.00248] [Citation(s) in RCA: 12] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/29/2018] [Accepted: 02/26/2019] [Indexed: 02/04/2023] Open
Abstract
The translation system is a sophisticated machinery that synthesizes proteins from 20 canonical amino acids. Recently, the repertoire of such composition has been expanded by the introduction of non-canonical amino acids (ncAAs) with the genetic code expansion strategy, which provides proteins with designed properties and structures for protein studies and engineering. Although the genetic code expansion strategy has been mostly implemented by using living cells as the host, a number of limits such as poor cellular uptake or solubility of specific ncAA substrates and the toxicity of target proteins have hindered the production of certain ncAA-modified proteins. To overcome those challenges, cell-free protein synthesis (CFPS) has been applied as it allows the precise control of reaction components. Several approaches have been recently developed to increase the purity and efficiency of ncAA incorporation in CFPS. Here, we summarized recent development of CFPS with an emphasis on its applications in generating site-specific protein post-translational modifications by the genetic code expansion strategy.
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Affiliation(s)
- Sumana Venkat
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, United States
| | - Hao Chen
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, United States
| | - Qinglei Gan
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, United States
| | - Chenguang Fan
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR, United States.,Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR, United States
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39
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Chen H, Venkat S, Hudson D, Wang T, Gan Q, Fan C. Site-Specifically Studying Lysine Acetylation of Aminoacyl-tRNA Synthetases. ACS Chem Biol 2019; 14:288-295. [PMID: 30642164 DOI: 10.1021/acschembio.8b01013] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
Abstract
Aminoacyl-tRNA synthetases (AARSs) charge their cognate tRNAs with corresponding amino acids, playing key roles in ribosomal protein synthesis. A series of proteomic studies have demonstrated that AARSs have levels of lysine acetylation much higher than those of other proteins in Escherichia coli. To study AARS acetylation, 25 site-specifically acetylated variants of four AARSs were generated by the genetic code expansion strategy. Kinetic analyses were performed to biochemically characterize the impact of site-specific acetylation on AARS functions, including amino acid activation, tRNA aminoacylation, and editing activities. The results showed that impacts of acetylation were different between class I and class II AARSs and also varied among the same class of AARSs. The results also showed that acetylation of threonyl-tRNA synthetase (ThrRS) could affect its editing function. Both in vivo and in vitro studies were further performed to explore the acetylation and deacetylation processes of ThrRS. Although nonenzymatic acetylation and CobB-dependent deacetylation were concluded, the results also indicated the existence of additional modifying enzymes or mechanisms for ThrRS acetylation and deacetylation.
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40
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Winter DL, Wilkins MR, Donald WA. Differential Ion Mobility–Mass Spectrometry for Detailed Analysis of the Proteome. Trends Biotechnol 2019; 37:198-213. [DOI: 10.1016/j.tibtech.2018.07.018] [Citation(s) in RCA: 30] [Impact Index Per Article: 6.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/30/2018] [Revised: 07/27/2018] [Accepted: 07/30/2018] [Indexed: 10/28/2022]
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41
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Versatility of Synthetic tRNAs in Genetic Code Expansion. Genes (Basel) 2018; 9:genes9110537. [PMID: 30405060 PMCID: PMC6267555 DOI: 10.3390/genes9110537] [Citation(s) in RCA: 9] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/16/2018] [Revised: 10/31/2018] [Accepted: 11/05/2018] [Indexed: 12/16/2022] Open
Abstract
Transfer RNA (tRNA) is a dynamic molecule used by all forms of life as a key component of the translation apparatus. Each tRNA is highly processed, structured, and modified, to accurately deliver amino acids to the ribosome for protein synthesis. The tRNA molecule is a critical component in synthetic biology methods for the synthesis of proteins designed to contain non-canonical amino acids (ncAAs). The multiple interactions and maturation requirements of a tRNA pose engineering challenges, but also offer tunable features. Major advances in the field of genetic code expansion have repeatedly demonstrated the central importance of suppressor tRNAs for efficient incorporation of ncAAs. Here we review the current status of two fundamentally different translation systems (TSs), selenocysteine (Sec)- and pyrrolysine (Pyl)-TSs. Idiosyncratic requirements of each of these TSs mandate how their tRNAs are adapted and dictate the techniques used to select or identify the best synthetic variants.
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42
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Chemla Y, Ozer E, Algov I, Alfonta L. Context effects of genetic code expansion by stop codon suppression. Curr Opin Chem Biol 2018; 46:146-155. [DOI: 10.1016/j.cbpa.2018.07.012] [Citation(s) in RCA: 24] [Impact Index Per Article: 4.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2018] [Revised: 05/01/2018] [Accepted: 07/13/2018] [Indexed: 10/28/2022]
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43
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Genome-Wide Quantification of the Effect of Gene Overexpression on Escherichia coli Growth. Genes (Basel) 2018; 9:genes9080414. [PMID: 30115866 PMCID: PMC6116040 DOI: 10.3390/genes9080414] [Citation(s) in RCA: 10] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 07/19/2018] [Revised: 08/10/2018] [Accepted: 08/10/2018] [Indexed: 12/18/2022] Open
Abstract
Recombinant protein production plays an essential role in both biological studies and pharmaceutical production. Escherichia coli is one of the most favorable hosts for this purpose. Although a number of strategies for optimizing protein production have been developed, the effect of gene overexpression on host cell growth has been much less studied. Here, we performed high-throughput tests on the E. coli a complete set of E. coli K-12 ORF archive (ASKA) collection to quantify the effects of overexpressing individual E. coli genes on its growth. The results indicated that overexpressing membrane-associated proteins or proteins with high abundances of branched-chain amino acids tended to impair cell growth, the latter of which could be remedied by amino acid supplementation. Through this study, we expect to provide an index for a fast pre-study estimate of host cell growth in order to choose proper rescuing approaches when working with different proteins.
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44
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Chen H, Venkat S, McGuire P, Gan Q, Fan C. Recent Development of Genetic Code Expansion for Posttranslational Modification Studies. Molecules 2018; 23:E1662. [PMID: 29986538 PMCID: PMC6100177 DOI: 10.3390/molecules23071662] [Citation(s) in RCA: 30] [Impact Index Per Article: 5.0] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/25/2018] [Revised: 07/03/2018] [Accepted: 07/05/2018] [Indexed: 12/29/2022] Open
Abstract
Nowadays advanced mass spectrometry techniques make the identification of protein posttranslational modifications (PTMs) much easier than ever before. A series of proteomic studies have demonstrated that large numbers of proteins in cells are modified by phosphorylation, acetylation and many other types of PTMs. However, only limited studies have been performed to validate or characterize those identified modification targets, mostly because PTMs are very dynamic, undergoing large changes in different growth stages or conditions. To overcome this issue, the genetic code expansion strategy has been introduced into PTM studies to genetically incorporate modified amino acids directly into desired positions of target proteins. Without using modifying enzymes, the genetic code expansion strategy could generate homogeneously modified proteins, thus providing powerful tools for PTM studies. In this review, we summarized recent development of genetic code expansion in PTM studies for research groups in this field.
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Affiliation(s)
- Hao Chen
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA.
| | - Sumana Venkat
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA.
| | - Paige McGuire
- Department of Biological Sciences, University of Arkansas, Fayetteville, AR 72701, USA.
| | - Qinglei Gan
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA.
| | - Chenguang Fan
- Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, USA.
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, USA.
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Venkat S, Chen H, Stahman A, Hudson D, McGuire P, Gan Q, Fan C. Characterizing Lysine Acetylation of Isocitrate Dehydrogenase in Escherichia coli. J Mol Biol 2018; 430:1901-1911. [PMID: 29733852 PMCID: PMC5988991 DOI: 10.1016/j.jmb.2018.04.031] [Citation(s) in RCA: 33] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/18/2018] [Revised: 04/18/2018] [Accepted: 04/24/2018] [Indexed: 12/21/2022]
Abstract
The Escherichia coli isocitrate dehydrogenase (ICDH) is one of the tricarboxylic acid cycle enzymes, playing key roles in energy production and carbon flux regulation. E. coli ICDH was the first bacterial enzyme shown to be regulated by reversible phosphorylation. However, the effect of lysine acetylation on E. coli ICDH, which has no sequence similarity with its counterparts in eukaryotes, is still unclear. Based on previous studies of E. coli acetylome and ICDH crystal structures, eight lysine residues were selected for mutational and kinetic analyses. They were replaced with acetyllysine by the genetic code expansion strategy or substituted with glutamine as a classic approach. Although acetylation decreased the overall ICDH activity, its effects were different site by site. Deacetylation tests demonstrated that the CobB deacetylase could deacetylate ICDH both in vivo and in vitro, but CobB was only specific for lysine residues at the protein surface. On the other hand, ICDH could be acetylated by acetyl-phosphate chemically in vitro. And in vivo acetylation tests indicated that the acetylation level of ICDH was correlated with the amounts of intracellular acetyl-phosphate. This study nicely complements previous proteomic studies to provide direct biochemical evidence for ICDH acetylation.
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Affiliation(s)
- Sumana Venkat
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, United States; Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, United States
| | - Hao Chen
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, United States; Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, United States
| | - Alleigh Stahman
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, United States
| | - Denver Hudson
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, United States
| | - Paige McGuire
- Department of Biological Sciences, University of Arkansas, Fayetteville, AR 72701, United States
| | - Qinglei Gan
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, United States
| | - Chenguang Fan
- Department of Chemistry and Biochemistry, University of Arkansas, Fayetteville, AR 72701, United States; Cell and Molecular Biology Program, University of Arkansas, Fayetteville, AR 72701, United States.
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Guebel DV, Torres NV. Influence of Glucose Availability and CRP Acetylation on the Genome-Wide Transcriptional Response of Escherichia coli: Assessment by an Optimized Factorial Microarray Analysis. Front Microbiol 2018; 9:941. [PMID: 29875739 PMCID: PMC5974110 DOI: 10.3389/fmicb.2018.00941] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/17/2018] [Accepted: 04/23/2018] [Indexed: 12/27/2022] Open
Abstract
Background: While in eukaryotes acetylation/deacetylation regulation exerts multiple pleiotropic effects, in Escherichia coli it seems to be more limited and less known. Hence, we aimed to progress in the characterization of this regulation by dealing with three convergent aspects: the effector enzymes involved, the master regulator CRP, and the dependence on glucose availability. Methods: The transcriptional response of E. coli BW25113 was analyzed across 14 relevant scenarios. These conditions arise when the wild type and four isogenic mutants (defective in deacetylase CobB, defective in N(ε)-lysine acetyl transferase PatZ, Q- and R-type mutants of protein CRP) are studied under three levels of glucose availability (glucose-limited chemostat and glucose-excess or glucose-exhausted in batch culture). The Q-type emulates a permanent stage of CRPacetylated, whereas the R-type emulates a permanent stage of CRPdeacetylated. The data were analyzed by an optimized factorial microarray method (Q-GDEMAR). Results: (a) By analyzing one mutant against the other, we were able to unravel the true genes that participate in the interaction between ΔcobB/ΔpatZ mutations and glucose availability; (b) Increasing stages of glucose limitation appear to be associated with the up-regulation of specific sets of target genes rather than with the loss of genes present when glucose is in excess; (c) Both CRPdeacetylated and CRPacetylated produce extensive changes in specific subsets of genes, but their number and identity depend on the glucose availability; (d) In other sub-sets of genes, the transcriptional effect of CRP seems to be independent of its acetylation or deacetylation; (e) Some specific ontology functions can be associated with each of the different sets of genes detected herein. Conclusions: CRP cannot be thought of only as an effector of catabolite repression, because it acts along all the glucose conditions tested (excess, limited, and exhausted), exerting both positive and negative effects through different sets of genes. Acetylation of CRP does not seem to be a binary form of regulation, as there is not a univocal relationship between its activation/inhibitory effect and its acetylation/deacetylation stage. All the combinatorial possibilities are observed. During the exponential growth phase, CRP also exerts a very significant transcriptional effect, mainly on flagellar assembly and chemotaxis (FDR = 7.2 × 10−44).
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Affiliation(s)
| | - Néstor V Torres
- Systems Biology and Mathematical Modelling Group, Department of Biochemistry, Microbiology, Cellular Biology and Genetics, Institute of Biomedical Technologies, Center for Biomedical Research of the Canary Islands, University of La Laguna, San Cristóbal de La Laguna, Spain
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