1
|
Weiss JL, Decker JC, Bolano A, Krahn N. Tuning tRNAs for improved translation. Front Genet 2024; 15:1436860. [PMID: 38983271 PMCID: PMC11231383 DOI: 10.3389/fgene.2024.1436860] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/22/2024] [Accepted: 06/06/2024] [Indexed: 07/11/2024] Open
Abstract
Transfer RNAs have been extensively explored as the molecules that translate the genetic code into proteins. At this interface of genetics and biochemistry, tRNAs direct the efficiency of every major step of translation by interacting with a multitude of binding partners. However, due to the variability of tRNA sequences and the abundance of diverse post-transcriptional modifications, a guidebook linking tRNA sequences to specific translational outcomes has yet to be elucidated. Here, we review substantial efforts that have collectively uncovered tRNA engineering principles that can be used as a guide for the tuning of translation fidelity. These principles have allowed for the development of basic research, expansion of the genetic code with non-canonical amino acids, and tRNA therapeutics.
Collapse
Affiliation(s)
- Joshua L Weiss
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - J C Decker
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Ariadna Bolano
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| | - Natalie Krahn
- Department of Biochemistry and Molecular Biology, University of Georgia, Athens, GA, United States
| |
Collapse
|
2
|
Jiang HK, Weng JH, Wang YH, Tsou JC, Chen PJ, Ko ALA, Söll D, Tsai MD, Wang YS. Rational design of the genetic code expansion toolkit for in vivo encoding of D-amino acids. Front Genet 2023; 14:1277489. [PMID: 37904728 PMCID: PMC10613524 DOI: 10.3389/fgene.2023.1277489] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Key Words] [Grants] [Track Full Text] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/14/2023] [Accepted: 09/18/2023] [Indexed: 11/01/2023] Open
Abstract
Once thought to be non-naturally occurring, D-amino acids (DAAs) have in recent years been revealed to play a wide range of physiological roles across the tree of life, including in human systems. Synthetic biologists have since exploited DAAs' unique biophysical properties to generate peptides and proteins with novel or enhanced functions. However, while peptides and small proteins containing DAAs can be efficiently prepared in vitro, producing large-sized heterochiral proteins poses as a major challenge mainly due to absence of pre-existing DAA translational machinery and presence of endogenous chiral discriminators. Based on our previous work demonstrating pyrrolysyl-tRNA synthetase's (PylRS') remarkable substrate polyspecificity, this work attempts to increase PylRS' ability in directly charging tRNAPyl with D-phenylalanine analogs (DFAs). We here report a novel, polyspecific Methanosarcina mazei PylRS mutant, DFRS2, capable of incorporating DFAs into proteins via ribosomal synthesis in vivo. To validate its utility, in vivo translational DAA substitution were performed in superfolder green fluorescent protein and human heavy chain ferritin, successfully altering both proteins' physiochemical properties. Furthermore, aminoacylation kinetic assays further demonstrated aminoacylation of DFAs by DFRS2 in vitro.
Collapse
Affiliation(s)
- Han-Kai Jiang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
- Taiwan International Graduate Program Chemical Biology and Molecular Biophysics, Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
- Department of Chemistry, National Tsing Hua University, Hsinchu, Taiwan
| | - Jui-Hung Weng
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Yi-Hui Wang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - Jo-Chu Tsou
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Pei-Jung Chen
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| | - An-Li Andrea Ko
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - 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
| | - Ming-Daw Tsai
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
| | - Yane-Shih Wang
- Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
- Taiwan International Graduate Program Chemical Biology and Molecular Biophysics, Institute of Biological Chemistry, Academia Sinica, Taipei, Taiwan
- Institute of Biochemical Sciences, National Taiwan University, Taipei, Taiwan
| |
Collapse
|
3
|
Thommen M, Draycheva A, Rodnina MV. Ribosome selectivity and nascent chain context in modulating the incorporation of fluorescent non-canonical amino acid into proteins. Sci Rep 2022; 12:12848. [PMID: 35896582 PMCID: PMC9329280 DOI: 10.1038/s41598-022-16932-7] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/11/2022] [Accepted: 07/18/2022] [Indexed: 11/09/2022] Open
Abstract
Fluorescence reporter groups are important tools to study the structure and dynamics of proteins. Genetic code reprogramming allows for cotranslational incorporation of non-canonical amino acids at any desired position. However, cotranslational incorporation of bulky fluorescence reporter groups is technically challenging and usually inefficient. Here we analyze the bottlenecks for the cotranslational incorporation of NBD-, BodipyFL- and Atto520-labeled Cys-tRNACys into a model protein using a reconstituted in-vitro translation system. We show that the modified Cys-tRNACys can be rejected during decoding due to the reduced ribosome selectivity for the modified aa-tRNA and the competition with native near-cognate aminoacyl-tRNAs. Accommodation of the modified Cys-tRNACys in the A site of the ribosome is also impaired, but can be rescued by one or several Gly residues at the positions −1 to −4 upstream of the incorporation site. The incorporation yield depends on the steric properties of the downstream residue and decreases with the distance from the protein N-terminus to the incorporation site. In addition to the full-length translation product, we find protein fragments corresponding to the truncated N-terminal peptide and the C-terminal fragment starting with a fluorescence-labeled Cys arising from a StopGo-like event due to a defect in peptide bond formation. The results are important for understanding the reasons for inefficient cotranslational protein labeling with bulky reporter groups and for designing new approaches to improve the yield of fluorescence-labeled protein.
Collapse
Affiliation(s)
- Michael Thommen
- Department of Physical Biochemistry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Albena Draycheva
- Department of Physical Biochemistry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany
| | - Marina V Rodnina
- Department of Physical Biochemistry, Max Planck Institute for Multidisciplinary Sciences, Göttingen, Germany.
| |
Collapse
|
4
|
Katoh T, Suga H. In Vitro Genetic Code Reprogramming for the Expansion of Usable Noncanonical Amino Acids. Annu Rev Biochem 2022; 91:221-243. [PMID: 35729073 DOI: 10.1146/annurev-biochem-040320-103817] [Citation(s) in RCA: 15] [Impact Index Per Article: 7.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Abstract
Genetic code reprogramming has enabled us to ribosomally incorporate various nonproteinogenic amino acids (npAAs) into peptides in vitro. The repertoire of usable npAAs has been expanded to include not only l-α-amino acids with noncanonical sidechains but also those with noncanonical backbones. Despite successful single incorporation of npAAs, multiple and consecutive incorporations often suffer from low efficiency or are even unsuccessful. To overcome this stumbling block, engineering approaches have been used to modify ribosomes, EF-Tu, and tRNAs. Here, we provide an overview of these in vitro methods that are aimed at optimal expansion of the npAA repertoire and their applications for the development of de novo bioactive peptides containing various npAAs.
Collapse
Affiliation(s)
- Takayuki Katoh
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo, Japan; ,
| | - Hiroaki Suga
- Department of Chemistry, Graduate School of Science, The University of Tokyo, Tokyo, Japan; ,
| |
Collapse
|
5
|
Abstract
Over the past decade, harnessing the cellular protein synthesis machinery to incorporate non-canonical amino acids (ncAAs) into tailor-made peptides has significantly advanced many aspects of molecular science. More recently, groundbreaking progress in our ability to engineer this machinery for improved ncAA incorporation has led to significant enhancements of this powerful tool for biology and chemistry. By revealing the molecular basis for the poor or improved incorporation of ncAAs, mechanistic studies of ncAA incorporation by the protein synthesis machinery have tremendous potential for informing and directing such engineering efforts. In this chapter, we describe a set of complementary biochemical and single-molecule fluorescence assays that we have adapted for mechanistic studies of ncAA incorporation. Collectively, these assays provide data that can guide engineering of the protein synthesis machinery to expand the range of ncAAs that can be incorporated into peptides and increase the efficiency with which they can be incorporated, thereby enabling the full potential of ncAA mutagenesis technology to be realized.
Collapse
|
6
|
Monajemi H, M Zain S, Wan Abdullah WAT. A new step in kinetic proofreading due to misacylated-tRNA during ribosomal peptide bond formation. NUCLEOSIDES, NUCLEOTIDES & NUCLEIC ACIDS 2021; 40:635-646. [PMID: 34047250 DOI: 10.1080/15257770.2021.1923742] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 05/07/2020] [Revised: 04/03/2021] [Accepted: 04/26/2021] [Indexed: 10/21/2022]
Abstract
The translational accuracy in protein synthesis is contributed to by several mechanisms in the ribosome, generally called kinetic proofreading. This process in the ribosome inhibits the non-cognate codon-anticodon interaction. However, it is not sufficient for fidelity of protein synthesis since a wrong amino acid can easily be added to the growing polypeptide chain if a tRNA while cognate to the mRNA, carries a non-cognate amino acid. Therefore, additional to the kinetic proofreading, there must be some hitherto unknown characteristic in misacylated-tRNAs to stop the process of protein synthesis if such misacylated-tRNA is accommodated in the ribosomal A-site. In order to understand this characteristic, we have performed computational quantum chemistry analysis on five different tRNA molecules, each one attached to five different amino acids with one being cognate to the tRNA and the other four non-cognate. This study shows the importance of aminoacyl-tRNA binding energy in ensuring fidelity of protein synthesis.
Collapse
Affiliation(s)
- Hadieh Monajemi
- Department of Chemistry, University of Malaya, Kuala Lumpur, Malaysia
- Data Intensive Computing Centre, Research & Innovation Complex, University of Malaya, Kuala Lumpur, Malaysia
- Department of Physics, University of Malaya, Kuala Lumpur, Malaysia
| | | | | |
Collapse
|
7
|
Dedkova LM, Hecht SM. Expanding the Scope of Protein Synthesis Using Modified Ribosomes. J Am Chem Soc 2019; 141:6430-6447. [PMID: 30901982 DOI: 10.1021/jacs.9b02109] [Citation(s) in RCA: 26] [Impact Index Per Article: 5.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
The ribosome produces all of the proteins and many of the peptides present in cells. As a macromolecular complex composed of both RNAs and proteins, it employs a constituent RNA to catalyze the formation of peptide bonds rapidly and with high fidelity. Thus, the ribosome can be argued to represent the key link between the RNA World, in which RNAs were the primary catalysts, and present biological systems in which protein catalysts predominate. In spite of the well-known phylogenetic conservation of rRNAs through evolutionary history, rRNAs can be altered readily when placed under suitable pressure, e.g. in the presence of antibiotics which bind to functionally critical regions of rRNAs. While the structures of rRNAs have been altered intentionally for decades to enable the study of their role(s) in the mechanism of peptide bond formation, it is remarkable that the purposeful alteration of rRNA structure to enable the elaboration of proteins and peptides containing noncanonical amino acids has occurred only recently. In this Perspective, we summarize the history of rRNA modifications, and demonstrate how the intentional modification of 23S rRNA in regions critical for peptide bond formation now enables the direct ribosomal incorporation of d-amino acids, β-amino acids, dipeptides and dipeptidomimetic analogues of the normal proteinogenic l-α-amino acids. While proteins containing metabolically important functional groups such as carbohydrates and phosphate groups are normally elaborated by the post-translational modification of nascent polypeptides, the use of modified ribosomes to produce such polymers directly is also discussed. Finally, we describe the elaboration of such modified proteins both in vitro and in bacterial cells, and suggest how such novel biomaterials may be exploited in future studies.
Collapse
Affiliation(s)
- Larisa M Dedkova
- Biodesign Center for BioEnergetics and School of Molecular Sciences , Arizona State University , Tempe , Arizona 85287 , United States
| | - Sidney M Hecht
- Biodesign Center for BioEnergetics and School of Molecular Sciences , Arizona State University , Tempe , Arizona 85287 , United States
| |
Collapse
|
8
|
Liljeruhm J, Wang J, Kwiatkowski M, Sabari S, Forster AC. Kinetics of d-Amino Acid Incorporation in Translation. ACS Chem Biol 2019; 14:204-213. [PMID: 30648860 DOI: 10.1021/acschembio.8b00952] [Citation(s) in RCA: 7] [Impact Index Per Article: 1.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/28/2022]
Abstract
Despite the stereospecificity of translation for l-amino acids (l-AAs) in vivo, synthetic biologists have enabled ribosomal incorporation of d-AAs in vitro toward encoding polypeptides with pharmacologically desirable properties. However, the steps in translation limiting d-AA incorporation need clarification. In this work, we compared d- and l-Phe incorporation in translation by quench-flow kinetics, measuring 250-fold slower incorporation into the dipeptide for the d isomer from a tRNAPhe-based adaptor (tRNAPheB). Incorporation was moderately hastened by tRNA body swaps and higher EF-Tu concentrations, indicating that binding by EF-Tu can be rate-limiting. However, from tRNAAlaB with a saturating concentration of EF-Tu, the slow d-Phe incorporation was unexpectedly very efficient in competition with incorporation of the l isomer, indicating fast binding to EF-Tu, fast binding of the resulting complex to the ribosome, and rate-limiting accommodation/peptide bond formation. Subsequent elongation with an l-AA was confirmed to be very slow and inefficient. This understanding helps rationalize incorporation efficiencies in vitro and stereospecific mechanisms in vivo and suggests approaches for improving incorporation.
Collapse
Affiliation(s)
- Josefine Liljeruhm
- Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, 751 24 Uppsala, Sweden
| | - Jinfan Wang
- Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, 751 24 Uppsala, Sweden
| | - Marek Kwiatkowski
- Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, 751 24 Uppsala, Sweden
| | - Samudra Sabari
- Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, 751 24 Uppsala, Sweden
| | - Anthony C. Forster
- Department of Cell and Molecular Biology, Uppsala University, Husargatan 3, Box 596, 751 24 Uppsala, Sweden
| |
Collapse
|