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Hu Z, Liang J, Su T, Zhang D, Li H, Gao X, Yao W, Song X. Minimizing the Anticodon-Recognized Loop of Methanococcus jannaschii Tyrosyl-tRNA Synthetase to Improve the Efficiency of Incorporating Noncanonical Amino Acids. Biomolecules 2023; 13:biom13040610. [PMID: 37189358 DOI: 10.3390/biom13040610] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/03/2023] [Revised: 03/23/2023] [Accepted: 03/25/2023] [Indexed: 03/31/2023] Open
Abstract
In the field of genetic code expansion (GCE), improvements in the efficiency of noncanonical amino acid (ncAA) incorporation have received continuous attention. By analyzing the reported gene sequences of giant virus species, we noticed some sequence differences at the tRNA binding interface. On the basis of the structural and activity differences between Methanococcus jannaschii Tyrosyl-tRNA Synthetase (MjTyrRS) and mimivirus Tyrosyl-tRNA Synthetase (MVTyrRS), we found that the size of the anticodon-recognized loop of MjTyrRS influences its suppression activity regarding triplet and specific quadruplet codons. Therefore, three MjTyrRS mutants with loop minimization were designed. The suppression of wild-type MjTyrRS loop-minimized mutants increased by 1.8–4.3-fold, and the MjTyrRS variants enhanced the activity of the incorporation of ncAAs by 15–150% through loop minimization. In addition, for specific quadruplet codons, the loop minimization of MjTyrRS also improves the suppression efficiency. These results suggest that loop minimization of MjTyrRS may provide a general strategy for the efficient synthesis of ncAAs-containing proteins.
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2
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Stephen P, Ye S, Zhou M, Song J, Zhang R, Wang ED, Giegé R, Lin SX. Structure of Escherichia coli Arginyl-tRNA Synthetase in Complex with tRNA Arg: Pivotal Role of the D-loop. J Mol Biol 2018; 430:1590-1606. [PMID: 29678554 DOI: 10.1016/j.jmb.2018.04.011] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.0] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/12/2018] [Revised: 03/16/2018] [Accepted: 04/10/2018] [Indexed: 10/17/2022]
Abstract
Aminoacyl-tRNA synthetases are essential components in protein biosynthesis. Arginyl-tRNA synthetase (ArgRS) belongs to the small group of aminoacyl-tRNA synthetases requiring cognate tRNA for amino acid activation. The crystal structure of Escherichia coli (Eco) ArgRS has been solved in complex with tRNAArg at 3.0-Å resolution. With this first bacterial tRNA complex, we are attempting to bridge the gap existing in structure-function understanding in prokaryotic tRNAArg recognition. The structure shows a tight binding of tRNA on the synthetase through the identity determinant A20 from the D-loop, a tRNA recognition snapshot never elucidated structurally. This interaction of A20 involves 5 amino acids from the synthetase. Additional contacts via U20a and U16 from the D-loop reinforce the interaction. The importance of D-loop recognition in EcoArgRS functioning is supported by a mutagenesis analysis of critical amino acids that anchor tRNAArg on the synthetase; in particular, mutations at amino acids interacting with A20 affect binding affinity to the tRNA and specificity of arginylation. Altogether the structural and functional data indicate that the unprecedented ArgRS crystal structure represents a snapshot during functioning and suggest that the recognition of the D-loop by ArgRS is an important trigger that anchors tRNAArg on the synthetase. In this process, A20 plays a major role, together with prominent conformational changes in several ArgRS domains that may eventually lead to the mature ArgRS:tRNA complex and the arginine activation. Functional implications that could be idiosyncratic to the arginine identity of bacterial ArgRSs are discussed.
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Affiliation(s)
- Preyesh Stephen
- Laboratory of Molecular Endocrinology, CHU Research Center and Laval University, Québec, Canada
| | - Sheng Ye
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China
| | - Ming Zhou
- Laboratory of Molecular Endocrinology, CHU Research Center and Laval University, Québec, Canada
| | - Jian Song
- Laboratory of Molecular Endocrinology, CHU Research Center and Laval University, Québec, Canada
| | - Rongguang Zhang
- National Laboratory of Biomacromolecules, Institute of Biophysics, Chinese Academy of Sciences, Beijing, China; Shanghai Institutes of Biochemistry and Cell Biology, SIBS, Shanghai, China.
| | - En-Duo Wang
- Shanghai Institutes of Biochemistry and Cell Biology, SIBS, Shanghai, China.
| | - Richard Giegé
- Institut de Biologie Moléculaire et Cellulaire, CNRS and Université de Strasbourg, Strasbourg Cedex, France
| | - Sheng-Xiang Lin
- Laboratory of Molecular Endocrinology, CHU Research Center and Laval University, Québec, Canada; Shanghai Institutes of Biochemistry and Cell Biology, SIBS, Shanghai, China.
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Wang N, Ju T, Niu W, Guo J. Fine-tuning interaction between aminoacyl-tRNA synthetase and tRNA for efficient synthesis of proteins containing unnatural amino acids. ACS Synth Biol 2015; 4:207-12. [PMID: 24847685 PMCID: PMC4384836 DOI: 10.1021/sb500195w] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 02/01/2023]
Abstract
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By
using a directed evolution approach, we have identified aminoacyl-tRNA
synthetase variants with significantly enhanced activity for the incorporation
of unnatural amino acids into proteins in response to the amber nonsense
codon in bacteria. We demonstrated that the optimization of anticodon
recognition of tRNA by aminoacyl-tRNA synthetase led to improved incorporation
efficiency that is unnatural amino acid-specific. The findings will
facilitate the creation of an optimized system for the genetic incorporation
of unnatural amino acids in bacteria.
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Affiliation(s)
- Nanxi Wang
- Department
of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Tong Ju
- Department
of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Wei Niu
- Department
of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
| | - Jiantao Guo
- Department
of Chemistry, University of Nebraska-Lincoln, Lincoln, Nebraska 68588, United States
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Interdomain communication modulates the tRNA-dependent pre-transfer editing of leucyl-tRNA synthetase. Biochem J 2013; 449:123-31. [PMID: 23035846 DOI: 10.1042/bj20121258] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/17/2022]
Abstract
EcLeuRS [Escherichia coli LeuRS (leucyl-tRNA synthetase)] has evolved both tRNA-dependent pre- and post-transfer editing capabilities to ensure catalytic specificity. Both editing functions rely on the entry of the tRNA CCA tail into the editing domain of the LeuRS enzyme, which, according to X-ray crystal structural studies, leads to a dynamic disordered orientation of the interface between the synthetic and editing domains. The results of the present study show that this tRNA-triggered conformational rearrangement leads to interdomain communication between the editing and synthetic domains through their interface, and this communication mechanism modulates the activity of tRNA-dependent pre-transfer editing. Furthermore, tRNA-dependent editing reaction inhibits misactivating non-cognate amino acids from the synthetic active site. These results also suggested a novel quality control mechanism of EcLeuRS which is achieved through the co-ordination between the synthetic and editing domains.
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Saruwatari Y, Wada T, Takita T, Inouye K. Substrate-induced conformational changes of the truncated catalytic domain of Geobacillus stearothermophilus lysyl-tRNA synthetase as examined by fluorescence. BIOCHIMICA ET BIOPHYSICA ACTA-PROTEINS AND PROTEOMICS 2008; 1784:1633-40. [DOI: 10.1016/j.bbapap.2008.07.003] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/08/2008] [Revised: 06/15/2008] [Accepted: 07/07/2008] [Indexed: 11/16/2022]
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Pham Y, Li L, Kim A, Erdogan O, Weinreb V, Butterfoss GL, Kuhlman B, Carter CW. A minimal TrpRS catalytic domain supports sense/antisense ancestry of class I and II aminoacyl-tRNA synthetases. Mol Cell 2007; 25:851-62. [PMID: 17386262 DOI: 10.1016/j.molcel.2007.02.010] [Citation(s) in RCA: 72] [Impact Index Per Article: 4.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/02/2006] [Revised: 01/03/2007] [Accepted: 02/05/2007] [Indexed: 10/23/2022]
Abstract
The emergence of polypeptide catalysts for amino acid activation, the slowest step in protein synthesis, poses a significant puzzle associated with the origin of biology. This problem is compounded as the 20 contemporary aminoacyl-tRNA synthetases belong to two quite distinct families. We describe here the use of protein design to show experimentally that a minimal class I aminoacyl-tRNA synthetase active site might have functioned in the distant past. We deleted the anticodon binding domain from tryptophanyl-tRNA synthetase and fused the discontinuous segments comprising its active site. The resulting 130 residue minimal catalytic domain activates tryptophan. This residual catalytic activity constitutes the first experimental evidence that the conserved class I signature sequences, HIGH and KMSKS, might have arisen in-frame, opposite motifs 2 and 1 from class II, as complementary sense and antisense strands of the same ancestral gene.
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Affiliation(s)
- Yen Pham
- Department of Biochemistry and Biophysics, University of North Carolina at Chapel Hill, Chapel Hill, NC 27599, USA
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Zhao MW, Zhu B, Hao R, Xu MG, Eriani G, Wang ED. Leucyl-tRNA synthetase from the ancestral bacterium Aquifex aeolicus contains relics of synthetase evolution. EMBO J 2005; 24:1430-9. [PMID: 15775966 PMCID: PMC1142543 DOI: 10.1038/sj.emboj.7600618] [Citation(s) in RCA: 33] [Impact Index Per Article: 1.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/27/2004] [Accepted: 02/15/2005] [Indexed: 11/10/2022] Open
Abstract
The editing reactions catalyzed by aminoacyl-tRNA synthetases are critical for the faithful protein synthesis by correcting misactivated amino acids and misaminoacylated tRNAs. We report that the isolated editing domain of leucyl-tRNA synthetase from the deep-rooted bacterium Aquifex aeolicus (alphabeta-LeuRS) catalyzes the hydrolytic editing of both mischarged tRNA(Leu) and minihelix(Leu). Within the domain, we have identified a crucial 20-amino-acid peptide that confers editing capacity when transplanted into the inactive Escherichia coli LeuRS editing domain. Likewise, fusion of the beta-subunit of alphabeta-LeuRS to the E. coli editing domain activates its editing function. These results suggest that alphabeta-LeuRS still carries the basic features from a primitive synthetase molecule. It has a remarkable capacity to transfer autonomous active modules, which is consistent with the idea that modern synthetases arose after exchange of small idiosyncratic domains. It also has a unique alphabeta-heterodimeric structure with separated catalytic and tRNA-binding sites. Such an organization supports the tRNA/synthetase coevolution theory that predicts sequential addition of tRNA and synthetase domains.
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Affiliation(s)
- Ming-Wei Zhao
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai, PR China
| | - Bin Zhu
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai, PR China
| | - Rui Hao
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai, PR China
| | - Min-Gang Xu
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai, PR China
| | - Gilbert Eriani
- UPR9002, IBMC du CNRS and Université Louis Pasteur, Strasbourg, France
| | - En-Duo Wang
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, The Chinese Academy of Sciences, Graduate School of the Chinese Academy of Sciences, Shanghai, PR China
- Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, 320 Yeu Yang Road, Shanghai 200031, China. Tel.: +86 21 549 21241; Fax: +86 21 549 21011; E-mail:
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Kobayashi T, Nureki O, Ishitani R, Yaremchuk A, Tukalo M, Cusack S, Sakamoto K, Yokoyama S. Structural basis for orthogonal tRNA specificities of tyrosyl-tRNA synthetases for genetic code expansion. Nat Struct Mol Biol 2003; 10:425-32. [PMID: 12754495 DOI: 10.1038/nsb934] [Citation(s) in RCA: 171] [Impact Index Per Article: 8.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/21/2003] [Accepted: 04/22/2003] [Indexed: 11/09/2022]
Abstract
The archaeal/eukaryotic tyrosyl-tRNA synthetase (TyrRS)-tRNA(Tyr) pairs do not cross-react with their bacterial counterparts. This 'orthogonal' condition is essential for using the archaeal pair to expand the bacterial genetic code. In this study, the structure of the Methanococcus jannaschii TyrRS-tRNA(Tyr)-L-tyrosine complex, solved at a resolution of 1.95 A, reveals that this archaeal TyrRS strictly recognizes the C1-G72 base pair, whereas the bacterial TyrRS recognizes the G1-C72 in a different manner using different residues. These diverse tRNA recognition modes form the basis for the orthogonality. The common tRNA(Tyr) identity determinants (the discriminator, A73 and the anticodon residues) are also recognized in manners different from those of the bacterial TyrRS. Based on this finding, we created a mutant TyrRS that aminoacylates the amber suppressor tRNA with C34 65 times more efficiently than does the wild-type enzyme.
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Affiliation(s)
- Takatsugu Kobayashi
- Department of Biophysics and Biochemistry, Graduate School of Science, The University of Tokyo, 7-3-1 Hongo, Bunkyo-ku, Tokyo 113-0033, Japan
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Takita T, Nakagoshi M, Inouye K, Tonomura B. Lysyl-tRNA synthetase from Bacillus stearothermophilus: the Trp314 residue is shielded in a non-polar environment and is responsible for the fluorescence changes observed in the amino acid activation reaction. J Mol Biol 2003; 325:677-95. [PMID: 12507472 DOI: 10.1016/s0022-2836(02)01238-x] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/27/2022]
Abstract
Three Trp variants of lysyl-tRNA synthetase from Bacillus stearothermophilus, in which either one or both of the two Trp residues within the enzyme (Trp314 and Trp332) were substituted by a Phe residue, were produced by site-directed mutagenesis without appreciable loss of catalytic activity. The following two phenomena were observed with W332F and with the wild-type enzyme, but not with W314F: (1) the addition of L-lysine alone decreased the protein fluorescence of the enzyme, but the addition of ATP alone did not; (2) the subsequent addition of ATP after the addition of excess L-lysine restored the fluorescence to its original level. Fluorometry under various conditions and UV-absorption spectroscopy revealed that Trp314, which was about 20A away from the lysine binding site and was shielded in a non-polar environment, was solely responsible for the fluorescence changes of the enzyme in the L-lysine activation reaction. Furthermore, the microenvironmental conditions around the residue were made more polar upon the binding of L-lysine, though its contact with the solvent was still restricted. It was suggested that Trp314 was located in a less polar environment than was Trp332, after comparison of the wavelengths at the peaks of fluorescence emission and of the relative fluorescence quantum yields. Trp332 was thought, based on the fluorescence quenching by some perturbants and the chemical modification with N-bromosuccinimide, to be on the surface of the enzyme, whereas Trp314 was buried inside. The UV absorption difference spectra induced by the L-lysine binding indicated that the state of Trp314, including its electrostatic environment, changed during the process, but Trp332 did not change. The increased fluorescence from Trp314 at acidic pH compared with that at neutral pH suggests that carboxylate(s) are in close proximity to the Trp314 residue.
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Affiliation(s)
- Teisuke Takita
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kitashirakawa, Kyoto 606-8502, Japan.
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Takita T, Inouye K. Transition state stabilization by the N-terminal anticodon-binding domain of lysyl-tRNA synthetase. J Biol Chem 2002; 277:29275-82. [PMID: 12019264 DOI: 10.1074/jbc.m200481200] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
Lysyl-tRNA synthetase from Bacillus stearothermophilus (B.s. LysRS) (EC ) catalyzes aminoacylation of tRNA(Lys) with l-lysine, in which l-lysine was first activated with ATP to yield an enzyme (lysyladenylate complex), and then the lysine molecule was transferred from the complex to tRNA(Lys). B.s. LysRS is a homodimeric enzyme with a subunit that consists of two domains, an N-terminal tRNA anticodon-binding domain (TAB-ND: Ser(1)-Pro(144)) and a C-terminal Class II-specific catalytic domain (CAT-CD: Lys(151)-Lys(493)). CAT-CD alone retained catalytic activity, although at a low level; TAB-ND alone showed no activity. Size exclusion chromatography revealed that CAT-CD exists as a dimer, whereas TAB-ND was a monomer. The formation of a complex consisting of these domains was detected with the guidance of surface plasmon resonance. In accordance with this, the addition of TAB-ND to CAT-CD significantly enhanced both the l-lysine activation and the tRNA aminoacylation reactions. Kinetic analysis showed that deletion of TAB-ND resulted in a significant destabilization of the transition state of CAT-CD in the l-lysine activation reaction but had little effect on the ground state of substrate binding. A significant role of a cross-subunit interaction in the enzyme between TAB-ND and CAT-CD was proposed for the stabilization of the transition state in the l-lysine activation reaction.
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Affiliation(s)
- Teisuke Takita
- Division of Food Science and Biotechnology, Graduate School of Agriculture, Kyoto University, Kitashirakawa, Kyoto 606-8502, Japan.
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Jia J, Xu F, Chen X, Chen L, Jin Y, Wang DTP. Two essential regions for tRNA recognition in Bacillus subtilis tryptophanyl-tRNA synthetase. Biochem J 2002; 365:749-56. [PMID: 11966471 PMCID: PMC1222715 DOI: 10.1042/bj20020141] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 01/23/2002] [Revised: 04/16/2002] [Accepted: 04/19/2002] [Indexed: 11/17/2022]
Abstract
Bacillus subtilis tryptophanyl-tRNA synthetase (TrpRS) is a homodimeric enzyme. A model for its ability to recognize tRNA(Trp) in B. subtilis was proposed by using computer modelling. This was based on the the fact that there is high homology among bacterial TrpRSs [Chen, Jiang, Jin and Wang (2001) Acta Biochim. Biophys. Sinica 33, 687-690], in which the enzyme dimer binds to two tRNA(Trp) molecules and each tRNA(Trp) is bound to two different domains across the surface of the dimer. In this work, three deletion mutants of TrpRS were constructed and their products were purified. After determining the kinetic parameters of the mutants in the two-step reaction, it was found that the relative activities of wild-type and mutant enzymes had changed little in the ATP-pyrophosphate exchange reaction. In contrast, the activities of three mutant proteins were much decreased in the tRNA(Trp) aminoacylation assay. Deletion of residues 108-122 and residues 234-238 caused 44% and 80% reductions in the activity, respectively. When both regions were deleted, the aminoacylation activity of the TrpRS mutant was too low to be determined using tRNA(Trp) at the limiting concentration. Gel-retardation assays showed that the acceptor minihelix and the anticodon microhelix were recognized by the domains of TrpRS spanning residues 108-122 and residues 234-238 respectively. In addition, the deletion of amino acids 234-238 affected the normal induced expression of TrpRS at 37 degrees C. In conclusion, residues 108-122 and 234-238 were found essential for tRNA(Trp) recognition.
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Affiliation(s)
- Jie Jia
- State Key Laboratory of Molecular Biology, Institute of Biochemistry and Cell Biology, Shanghai Institutes for Biological Sciences, Chinese Academy of Sciences, Shanghai 200031, People's Republic of China
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Ramesh V, RajBhandary UL. Importance of the anticodon sequence in the aminoacylation of tRNAs by methionyl-tRNA synthetase and by valyl-tRNA synthetase in an Archaebacterium. J Biol Chem 2001; 276:3660-5. [PMID: 11058596 DOI: 10.1074/jbc.m008206200] [Citation(s) in RCA: 21] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [MESH Headings] [Grants] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022] Open
Abstract
The mode of recognition of tRNAs by aminoacyl-tRNA synthetases and translation factors is largely unknown in archaebacteria. To study this process, we have cloned the wild type initiator tRNA gene from the moderate halophilic archaebacterium Haloferax volcanii and mutants derived from it into a plasmid capable of expressing the tRNA in these cells. Analysis of tRNAs in vivo show that the initiator tRNA is aminoacylated but is not formylated in H. volcanii. This result provides direct support for the notion that protein synthesis in archaebacteria is initiated with methionine and not with formylmethionine. We have analyzed the effect of two different mutations (CAU-->CUA and CAU-->GAC) in the anticodon sequence of the initiator tRNA on its recognition by the aminoacyl-tRNA synthetases in vivo. The CAU-->CUA mutant was not aminoacylated to any significant extent in vivo, suggesting the importance of the anticodon in aminoacylation of tRNA by methionyl-tRNA synthetase. This mutant initiator tRNA can, however, be aminoacylated in vitro by the Escherichia coli glutaminyl-tRNA synthetase, suggesting that the lack of aminoacylation is due to the absence in H. volcanii of a synthetase, which recognizes the mutant tRNA. Archaebacteria lack glutaminyl-tRNA synthetase and utilize a two-step pathway involving glutamyl-tRNA synthetase and glutamine amidotransferase to generate glutaminyl-tRNA. The lack of aminoacylation of the mutant tRNA indicates that this mutant tRNA is not a substrate for the H. volcanii glutamyl-tRNA synthetase. The CAU-->GAC anticodon mutant is most likely aminoacylated with valine in vivo. Thus, the anticodon plays an important role in the recognition of tRNA by at least two of the halobacterial aminoacyl-tRNA synthetases.
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Affiliation(s)
- V Ramesh
- Department of Biology, Massachusetts Institute of Technology, Cambridge, Massachusetts 02139, USA
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Fechter P, Rudinger-Thirion J, Tukalo M, Giegé R. Major tyrosine identity determinants in Methanococcus jannaschii and Saccharomyces cerevisiae tRNA(Tyr) are conserved but expressed differently. EUROPEAN JOURNAL OF BIOCHEMISTRY 2001; 268:761-7. [PMID: 11168416 DOI: 10.1046/j.1432-1327.2001.01931.x] [Citation(s) in RCA: 55] [Impact Index Per Article: 2.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/20/2022]
Abstract
Using in vitro tRNA transcripts and minihelices it was shown that the tyrosine identity for tRNA charging by tyrosyl-tRNA synthetase (TyrRS) from the archaeon Methanococcus jannaschii is determined by six nucleotides: the discriminator base A73 and the first base-pair C1-G72 in the acceptor stem together with the anticodon triplet. The anticodon residues however, participate only weakly in identity determination, especially residues 35 and 36. The completeness of the aforementioned identity set was verified by its tranfer into several tRNAs which then become as efficiently tyrosylatable as the wild-type transcript from M. jannaschii. Temperature dependence experiments on both the structure and the tyrosylation properties of M. jannaschii and yeast tRNA(Tyr) transcripts show that the archaeal transcript has greater structural stability and enhanced aminoacylation behaviour than the yeast transcript. Tyrosine identity in M. jannaschii is compared to that in yeast, and the conservation of the major determinant in both organisms, namely the C1-G72 pair, gives additional support to the existence of a functional connection between archaeal and eukaryotic aminoacylation systems.
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Affiliation(s)
- P Fechter
- Département Mécanismes et Macromolécules de la Synthèse Protéique et Cristallogenèse, Institut de Biologie Moléculaire et Cellulaire du CNRS, Strasbourg, France
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Class-1 polypeptide chain release factors are structurally and functionally similar to suppressor tRNAs and comprise different structural-functional families of prokaryotic/mitochondrial and eukaryotic/archaebacterial factors. Mol Biol 2000. [DOI: 10.1007/bf02759667] [Citation(s) in RCA: 12] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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