1
|
Spiegel PC, Ermolenko DN, Noller HF. Elongation factor G stabilizes the hybrid-state conformation of the 70S ribosome. RNA (NEW YORK, N.Y.) 2007; 13:1473-82. [PMID: 17630323 PMCID: PMC1950763 DOI: 10.1261/rna.601507] [Citation(s) in RCA: 101] [Impact Index Per Article: 5.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/16/2023]
Abstract
Following peptide bond formation, transfer RNAs (tRNAs) and messenger RNA (mRNA) are translocated through the ribosome, a process catalyzed by elongation factor EF-G. Here, we have used a combination of chemical footprinting, peptidyl transferase activity assays, and mRNA toeprinting to monitor the effects of EF-G on the positions of tRNA and mRNA relative to the A, P, and E sites of the ribosome in the presence of GTP, GDP, GDPNP, and fusidic acid. Chemical footprinting experiments show that binding of EF-G in the presence of the non-hydrolyzable GTP analog GDPNP or GDP.fusidic acid induces movement of a deacylated tRNA from the classical P/P state to the hybrid P/E state. Furthermore, stabilization of the hybrid P/E state by EF-G compromises P-site codon-anticodon interaction, causing frame-shifting. A deacylated tRNA bound to the P site and a peptidyl-tRNA in the A site are completely translocated to the E and P sites, respectively, in the presence of EF-G with GTP or GDPNP but not with EF-G.GDP. Unexpectedly, translocation with EF-G.GTP leads to dissociation of deacylated tRNA from the E site, while tRNA remains bound in the presence of EF-G.GDPNP, suggesting that dissociation of tRNA from the E site is promoted by GTP hydrolysis and/or EF-G release. Our results show that binding of EF-G in the presence of GDPNP or GDP.fusidic acid stabilizes the ribosomal intermediate hybrid state, but that complete translocation is supported only by EF-G.GTP or EF-G.GDPNP.
Collapse
Affiliation(s)
- P Clint Spiegel
- Center for Molecular Biology of RNA, Department of Molecular, Cell and Developmental Biology, University of California-Santa Cruz 95064, USA
| | | | | |
Collapse
|
2
|
Karimi R, Pavlov MY, Buckingham RH, Ehrenberg M. Novel roles for classical factors at the interface between translation termination and initiation. Mol Cell 1999; 3:601-9. [PMID: 10360176 DOI: 10.1016/s1097-2765(00)80353-6] [Citation(s) in RCA: 182] [Impact Index Per Article: 7.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
Abstract
The pathway of bacterial ribosome recycling following translation termination has remained obscure. Here, we elucidate two essential steps and describe the roles played by the three translation factors EF-G, RRF, and IF3. Release factor RF3 is known to catalyze the dissociation of RF1 or RF2 from ribosomes after polypeptide release. We show that the next step is dissociation of 50S subunits from the 70S posttermination complex and that it is catalyzed by RRF and EF-G and requires GTP hydrolysis. Removal of deacylated tRNA from the resulting 30S:mRNA:tRNA posttermination complex is then necessary to permit rapid 30S subunit recycling. We show that this step requires initiation factor IF3, whose role was previously thought to be restricted to promoting specific 30S initiation complex formation from free 30S subunits.
Collapse
Affiliation(s)
- R Karimi
- Department of Cell and Molecular Biology, Biomedical Center, Uppsala, Sweden
| | | | | | | |
Collapse
|
3
|
Rojo MA, Arias FJ, Iglesias R, Ferreras JM, Muñoz R, Escarmís C, Soriano F, López-Fando J, Méndez E, Girbés T. Cusativin, a new cytidine-specific ribonuclease accumulated in seeds of Cucumis sativus L. PLANTA 1994; 194:328-338. [PMID: 7765423 DOI: 10.1007/bf00197532] [Citation(s) in RCA: 20] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/27/1993] [Accepted: 02/24/1994] [Indexed: 05/22/2023]
Abstract
Dry seeds of Cucumis sativus L. were found to contain a heat-sensitive endoribonuclease of a novel type which we have named cusativin. It was purified to apparent electrophoretic homogeneity by chromatography through S-Sepharose Fast Flow, Sephadex G-75, CM-Sepharose, Superdex 75-FPLC (fast protein liquid chromatography) and Mono S-FPLC. It is a single unglycosylated polypeptide chain with an apparent molecular mass (M(r)) of 22900. Polyclonal anti-cusativin antibodies raised in rabbits only reacted with melonin, the translation inhibitor from Cucumis melo L. Functional, Western blot and enzyme-linked immunosorbent assay (ELISA) analyses indicated that cusativin is present in the coat and cotyledons of dry seeds, but not in embryonic axes. Cusativin is accumulated in maturing seeds. By contrast, after seed germination there is degradation of the cusativin present in cotyledons but not that present in the seed coat. The preference of cusativin for polynucleotide cleavage was poly(C) >> poly(A) acids, poly(U) and poly(G) being unaffected by cusativin. Under the denaturing conditions used for RNA sequencing, cusativin acted only on poly(C). Cusativin proved to be useful for RNA sequencing, in particular, complementing the data obtained with RNase CL3. Cusativin represents a new class of plant RNase and, as far as we are aware, is the first plant enzyme that shows cleavage specificity for cytidine under the denaturing conditions of RNA sequencing.
Collapse
Affiliation(s)
- M A Rojo
- Departamento de Bioquímica y Biología Molecular, Facultad de Ciencias, Universidad de Valladolid, Spain
| | | | | | | | | | | | | | | | | | | |
Collapse
|
4
|
Girbés T, Citores L, Ferreras JM, Rojo MA, Iglesias R, Muñoz R, Arias FJ, Calonge M, García JR, Méndez E. Isolation and partial characterization of nigrin b, a non-toxic novel type 2 ribosome-inactivating protein from the bark of Sambucus nigra L. PLANT MOLECULAR BIOLOGY 1993; 22:1181-1186. [PMID: 8400135 DOI: 10.1007/bf00028990] [Citation(s) in RCA: 49] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/22/2023]
Abstract
The bark of Sambucus nigra L. contains a non-toxic novel type 2 ribosome-inactivating protein that we named nigrin b. In vitro, nigrin b strongly inhibited mammalian protein synthesis but did not affect plant nor bacterial protein synthesis. The protein (M(r) 58,000) contains two subunits, A (M(r) 26,000) and B (M(r) 32,000); linked by disulphide bridge(s). Nigrin b was found to be an rRNA N-glycosidase of the rRNA of intact mammalian ribosomes and shares a very good N-terminal amino-acid sequence homology with the anti-HIV-1 proteins TAP 29 and trichosanthin.
Collapse
Affiliation(s)
- T Girbés
- Departamento de Bioquimíca y Biología Molecular, Facultad de Ciencias, Universidad de Valladolid, Spain
| | | | | | | | | | | | | | | | | | | |
Collapse
|
5
|
Girbés T, Citores L, Iglesias R, Ferreras J, Muñoz R, Rojo M, Arias F, García J, Méndez E, Calonge M. Ebulin 1, a nontoxic novel type 2 ribosome-inactivating protein from Sambucus ebulus L. leaves. J Biol Chem 1993. [DOI: 10.1016/s0021-9258(17)46829-3] [Citation(s) in RCA: 71] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/26/2022] Open
|
6
|
Iglesias R, Escarmis C, Alegre C, Ferreras JM, Girbés T. Fusidic acid-dependent ribosomal complexes protect Escherichia coli ribosomes from the action of the type 1 ribosome-inactivating protein crotin 2. FEBS Lett 1993; 318:189-92. [PMID: 7680006 DOI: 10.1016/0014-5793(93)80019-q] [Citation(s) in RCA: 18] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/26/2023]
Abstract
The type 1 ribosome-inactivating protein crotin 2 depurinated Escherichia coli ribosomes which, upon treatment of the isolated rRNA with acid aniline, released a fragment of around 240 nucleotides whose 5'-end sequence was 5'-GAGGACCGGAGUGGAC-3'. The formation of fusidic acid-dependent ribosomal complexes completely prevented release of the fragment. Ribosomes from crotin 2-pretreated fusidic acid complexes were insensitive to acid aniline. They released the RNA fragment only after a second treatment with crotin 2 and acid aniline whereas unprotected ribosomes released the fragment directly after acid aniline.
Collapse
Affiliation(s)
- R Iglesias
- Departamento de Bioquimíca y Biología Molecular, Facultad de Ciencias, Universidad de Valladolid, Spain
| | | | | | | | | |
Collapse
|
7
|
Lglesias R, Ferreras JM, Arias FJ, Muñoz R, Girbès T. Changes in the activity of the general amino acid permease fromSaccharomyces cerevisiae var.ellipsoideus during fermentation. Biotechnol Bioeng 1990; 36:808-10. [DOI: 10.1002/bit.260360808] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
|
8
|
Girbés T, Ferreras JM, Muñoz R, Alonso P. Effect of acute ethanol administration and nutritional status on secretory protein synthesis in isolated rat liver cells. Toxicol In Vitro 1989; 3:7-12. [PMID: 20702317 DOI: 10.1016/0887-2333(89)90017-9] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/18/1987] [Revised: 03/21/1988] [Indexed: 11/16/2022]
Abstract
Treatment of isolated rat liver cells with 20 mm-ethanol inhibited basal secretory protein synthesis by 30% only when the donors were starved for 48 hr, immediately before they were killed. This inhibition was unaffected by the presence of ethanol in the diet of the donor animals. Independently, d-glucose and l-proline enhanced rates of secretory protein synthesis in a dose-dependent manner but only in cells from 48-hr-fasted donors. This latter stimulation was prevented by the presence of 20 mm-ethanol in the incubation medium. By contrast, up to 100 mm-ethanol did not alter polypeptide synthesis by a post-mitochondrial supernatant from rat liver.
Collapse
Affiliation(s)
- T Girbés
- Departamento de Bioquimica, Biologia Molecular y Fisiologia, Facultad de Ciencias, Universidad de Valladolid, 47005 Valladolid, Spain
| | | | | | | |
Collapse
|
9
|
Robertson JM, Wintermeyer W. Mechanism of ribosomal translocation. tRNA binds transiently to an exit site before leaving the ribosome during translocation. J Mol Biol 1987; 196:525-40. [PMID: 2824784 DOI: 10.1016/0022-2836(87)90030-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 1.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/02/2023]
Abstract
Escherichia coli ribosomes have a site (E) to which deacylated tRNA binds transiently before leaving the ribosome during translocation. The affinity of the site is Mg2+ dependent and low at physiological Mg2+ concentrations. Correct codon-anticodon interaction is unnecessary in this site. With these features, the E site cannot reduce frameshift errors through additional mRNA anchorage. Occupancy of the A site does not influence the tRNA binding in the E site, although a conformational change of elongation factor G, brought about by GTP hydrolysis, is necessary for efficient tRNA release. The tRNA can dissociate unhindered from the E site when the elongation factor is bound to the ribosome by fusidic acid. During elongation, the thermodynamically stable state is not attained, since E site occupation inhibits translocation. However, the E site can aid elongation by providing an intermediate state for tRNA dissociation, dispersing the process into more than one step.
Collapse
Affiliation(s)
- J M Robertson
- Institute für Physiologische Chemie, Universität München, F.R.G
| | | |
Collapse
|
10
|
Spirin AS, Baranov VI, Polubesov GS, Serdyuk IN, May RP. Translocation makes the ribosome less compact. J Mol Biol 1987; 194:119-26. [PMID: 3302274 DOI: 10.1016/0022-2836(87)90720-0] [Citation(s) in RCA: 41] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/05/2023]
Abstract
Translating ribosomes of Escherichia coli were prepared either in the pre-translocation or in the post-translocation states by a special technique based on the use of poly(U)-Sepharose columns where the template was coupled to the matrix through splittable -S-S- bridges. Elongation factors were absent from the final preparations. A neutron scattering study of the translating ribosomes in the two functional states was performed at different contrasts (various 1H2O/2H2O mixtures). Under conditions of a high contrast for the protein constituent the radius of gyration of the post-translocation-state ribosomes was found to be slightly greater than that of the pre-translocation-state ribosomes. Using the results of this study the conclusion can be drawn that translocation is accompanied by a spatial displacement of some parts of the ribosome with a magnitude of several ångström units.
Collapse
|
11
|
Girbes T, Alonso P. Inhibition of protein synthesis by (aminooxy)acetate in rat liver. THE INTERNATIONAL JOURNAL OF BIOCHEMISTRY 1986; 18:537-42. [PMID: 3709936 DOI: 10.1016/0020-711x(86)90165-5] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/07/2023]
Abstract
(Aminooxy)acetate and D-cycloserine, two inhibitors of hepatic transamination reactions, inhibited also protein synthesis in isolated cells and postmitochondrial supernatants from rat liver. Both inhibitors acted in extracts only in concentrations higher than 1 mM. However, while D-cycloserine acted in isolated cells, as in extracts, (aminooxy)acetate inhibits protein synthesis in isolated cells by 50% of the control in the range 0.03-3 mM. NH+4 and H2O2, two by-products of (aminooxy)acetate degradation, inhibited protein synthesis in isolated liver cells, but at such a high concentration that the inhibition of protein synthesis carried out by (aminooxy)acetate cannot be explained by generation of these species. The results point out that the inhibitory action of (aminooxy)acetate on protein synthesis appears to require the integrity of the molecule.
Collapse
|
12
|
Abdurashidova GG, Tsvetkova EA, Chernyi AA, Kaminir LB, Budowsky EI. Intersubunit RNA-protein contacts in pre- and post-translocated E. coli ribosome. FEBS Lett 1985; 185:291-4. [PMID: 2581817 DOI: 10.1016/0014-5793(85)80925-x] [Citation(s) in RCA: 11] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/01/2023]
Abstract
Ribosomal proteins participating in intersubunit RNA-protein contacts (directly interacting with RNA of the opposite subunit) were determined by means of ultraviolet-induced cross-links in pre- and post-translocated ribosomal complexes, as well as in the free 70 S ribosome (tight couple) of E. coli. In these 3 complexes at least L1 and L9 proteins interact with 16 S RNA, while S6, S9/11 and S15 react with 23 S RNA. All these proteins ('hinge-joint' proteins) are clustered on the small protuberance of the 50 S subunit and on the platform of the 30 S subunit. Reduction in the number of other (variable) intersubunit RNA-protein contacts in the course of transition from the tight couple to the pre- and, finally, to the post-translocated state, demonstrates gradual loosening of intersubunit interactions in 70 S ribosome. Such a loosening ('opening') of the 70 S ribosome is determined by conformational changes in ribosomal subunits and/or in their relative arrangement, conjugated with alteration of the functional state of the ribosomal complex.
Collapse
|
13
|
Spirin AS. Ribosomal translocation: facts and models. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1985; 32:75-114. [PMID: 3911279 DOI: 10.1016/s0079-6603(08)60346-3] [Citation(s) in RCA: 88] [Impact Index Per Article: 2.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/08/2023]
|
14
|
Abstract
Electron microscopy results of Lake [J. Mol. Biol. (1976) 105, 131-159] and Vasiliev et al. [FEBS Lett. (1983) 155, 167-172] suggest that the 70 S ribosome has an open pocket or a cavity at the base of the L7/L12 stalk of the 50 S subunit, on the side of the 30 S subunit opposite to its bulge or platform. It is this pocket that is proposed here to be the site for binding and retention of two L-shaped tRNA molecules on the ribosome. The model proposed is consistent with the facts about interactions of the protein L7/L12 with the elongation factors (EF-Tu and EF-G) involved in tRNA binding and translocation, as well as with the data available on the participation of proteins S3, S5, S10, S14 and S19 in the formation of tRNA sites.
Collapse
|
15
|
Wagner T, Sprinzl M. Inhibition of ribosomal translocation by peptidyl transfer ribonucleic acid analogues. Biochemistry 1983; 22:94-8. [PMID: 6338920 DOI: 10.1021/bi00270a013] [Citation(s) in RCA: 22] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
Abstract
The activity of peptidyl-tRNALys-CpCp2'dA was measured in an in vitro poly(A)-dependent polypeptide synthesizing system derived from Escherichia coli. It has already been shown that Lys-tRNALys-CpCp2'dA is active as an acceptor and Ac2-Lys-tRNALys-Cp2'dA can donate its peptidyl residue but that the overall poly(A)-dependent synthesis of polylysine does not take place with Lys-tRNALys-CpCp2'dA [Wagner, T., Cramer, F., & Sprinzl, M. (1982) Biochemistry 21, 1521-1529]. This is due to the efficient inhibition of the EF-G-dependent translocation of the peptidyl-tRNA CpCp2'dA from the ribosomal A to the ribosomal P site. In addition, the EF-G-dependent release of the deacylated tRNALys-CpCp2'dA from the ribosomes is also inhibited. The action of the elongation factor G or some other ribosomal component participating in the translocation process requires the presence of the 2'-hydroxyl group on the terminal adenosine of tRNA. If this hydroxyl group is not present on the tRNA, the ribosomes remain locked in their pretranslocational state.
Collapse
|
16
|
Chetverin AB, Spirin AS. Bioenergetics and protein synthesis. BIOCHIMICA ET BIOPHYSICA ACTA 1982; 683:153-79. [PMID: 6295473 DOI: 10.1016/0304-4173(82)90009-x] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/19/2023]
|
17
|
|
18
|
Campuzano S, Modolell J. Effects of antibiotics, N-acetylaminoacyl-tRNA and other agents on the elongation-factor-Tu dependent and ribosome-dependent GTP hydrolysis promoted by 2'(3')-O-L-phenylalanyladenosine. EUROPEAN JOURNAL OF BIOCHEMISTRY 1981; 117:27-31. [PMID: 6114863 DOI: 10.1111/j.1432-1033.1981.tb06298.x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
Abstract
GTP hydrolysis on elongation factor (EF) Tu . ribosome complexes has been assayed in the presence of 2'(3')-O-L-phenylalanyladenosine (AdoPhe), i.e. the 3'-terminal portion of Phe-tRNAPhe. Several requirements of the reaction have been characterized. Maximal activity is observed at 60-120 mM NH4Cl and 5-15 mM magnesium acetate. The reaction requires the free sulfhydryl group of EF-Tu normally implicated in aminoacyl-tRNA binding. Intact EF-Tu cannot be replaced by a large tryptic fragment of EF-Tu (Mr 39,000) that retains the ability to bind guanosine nucleotides. The aminoglycoside antibiotics, neomycin C and several kanamycins and gentamicins, stimulate the AdoPhe-promoted GTPase. Surprisingly, however, other closely related antibiotics, like neomycin B, paromomycin and ribostamycin, are ineffectual, thus indicating subtle differences in the actions of these antibiotics. AcPhe-tRNAPhe, bound to the ribosomal A-site, stimulates the AdoPhe-promoted GTPase, but this compound or AcTyr-tRNATyr, present in unbound form, strongly inhibits the reaction. These results suggest that N-blocked aminoacyl-tRNAs form ternary complexes with EF-Tu . GTP, which have not been previously detected because of their low stability.
Collapse
|
19
|
Matzke AJ, Barta A, Kuechler E. Mechanism of translocation: relative arrangement of tRNA and mRNA on the ribosome. Proc Natl Acad Sci U S A 1980; 77:5110-4. [PMID: 6159638 PMCID: PMC350006 DOI: 10.1073/pnas.77.9.5110] [Citation(s) in RCA: 29] [Impact Index Per Article: 0.7] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023] Open
Abstract
AcPhe-tRNAPhe from yeast can be photocross-linked to poly(U) on Escherichia coli ribosomes. The photoreaction occurs at the wybutine base situated next to the 3' side of the anticodon. The kinetics and efficiency of crosslinking of AcPhe-Phe-tRNA are the same at both the acceptor site and the peptidyl site. Therefore, the orientation of wybutine with respect to the mRNA is similar in both the pretranslocational and posttranslocational states. AcPhe-Phe-tRNA crosslinked at the acceptor site can still be translocated to the peptidyl site, demonstrating that tRNA and mRNA are transported together. The experiments support a model of translocation in which the conformation of the anticodon loop of tRNA is similar in both the peptidyl site and the acceptor site.
Collapse
|
20
|
Kruse TA, Siboska GE, Sprinzl M, Clark BF. The effect of chemical modification of the CCA end of yeast tRNAPhe on its biological activity on ribosomes. EUROPEAN JOURNAL OF BIOCHEMISTRY 1980; 107:1-6. [PMID: 6995110 DOI: 10.1111/j.1432-1033.1980.tb04616.x] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/22/2023]
Abstract
Yeast tRNAPhe containing 2-thiocytidine (s2C) at position 75 was alkylated specifically at this residue. The biological activities of alkylated and native tRNAPhe were compared in an Escherichia coli protein-synthesizing system in vitro. The alkylated tRNAPhe proved to be active in all steps involved in the elongation phase but the rate of the peptide transfer reaction was somewhat lower when the alkylated tRNAPhe acted as an acceptor of peptidyl residues as compared to native tRNAPhe. These results raise the possibility for attaching spectroscopic or affinity labels at the s2C-75 residue of tRNAPhe without impairing the activity of the tRNA.
Collapse
|
21
|
Johnson AE, Cantor CR. Elongation factor-dependent affinity labeling of Escherichia coli ribosomes. J Mol Biol 1980; 138:273-97. [PMID: 6157827 DOI: 10.1016/0022-2836(80)90287-9] [Citation(s) in RCA: 23] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/18/2023]
|
22
|
Campuzano S, Modolell J. Hydrolysis of GTP on elongation factor Tu.ribosome complexes promoted by 2'(3')-O-L-phenylalanyladenosine. Proc Natl Acad Sci U S A 1980; 77:905-9. [PMID: 6987671 PMCID: PMC348390 DOI: 10.1073/pnas.77.2.905] [Citation(s) in RCA: 16] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 01/22/2023] Open
Abstract
In the presence of Escherichia coli ribosomes and elongation factor EF) Tu, 2'(3')-O-L-phenylalanyladenosine (AdoPhe), the 3'-terminal portion of Phe-tRNAPhe, promotes the hydrolysis of GTP. The reaction requires the presence of both 30S and 50S ribosomal subunits and of proteins L7/L12 on the 50S subunit, is unaffected by mRNA [poly(uridylic acid)], and is strongly stimulated by EF-Ts. It is proposed that the AdoPhe-dependent GTP hydrolysis, like that promoted by aminoacyl-tRNA, is mediated by a ternary complex with EF-Tu and GTP; however, in contrast to aminoacyl-tRNA, AdoPhe is probably not retained by ribosomes after GTP hydrolysis. Phe-tRNAPhe or N-acetyl-Phe-tRNAPhe bound to the ribosomal acceptor site do not inhibit, but even stimulate, GTP hydrolysis by AdoPhe.EF-Tu.GTP. Thus, the binding site for EF-Tu on the ribosome is probably available for interaction with AdoPhe.EF-Tu.GTP regardless of whether the nearby acceptor site is vacant of occupied with aminoacyl-tRNA or peptidyl-tRNA. The results demonstrate the critical role of the 3'-terminal region of aminoacyl-tRNA in activating the EF-Tu- plus ribosome-dependent GTPase.
Collapse
|
23
|
Campuzano S, Cabañas MJ, Modolell J. The binding of non-cognate Tyr-tRNATyr to poly(uridylic acid)-programmed Escherichia coli ribosomes. EUROPEAN JOURNAL OF BIOCHEMISTRY 1979; 100:133-9. [PMID: 385309 DOI: 10.1111/j.1432-1033.1979.tb02041.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
The poly(U)-dependent binding of Tyr-tRNATyr to Escherichia coli ribosomes has been studied using a highly purified system. Binding is maximal at 10 mM magnesium acetate (up to 0.7 molecule Tyr-tRNATyr/ribosome), and requires the presence of elongation factor (EF) T (a mixture of EF-Ts and EF-Tu), GTP, NH4+ ions and an aminoglycoside antibiotic (streptomycin, neomycin B, kanamycin B or gentamicin C1a). Under limiting and up to saturating concentrations of EF-T, one molecule of GTP is hydrolyzed per molecule of Tyr-tRNATyr bound, suggesting that 'proof-reading' mechanisms involving the hydrolysis of GTP are inoperative in the presence of the antibiotics. Binding of Tyr-tRNATyr apparently takes place at the ribosomal acceptor site, since peptide bonds are readily formed with N-acetyl-Phe-tRNA prebound to the ribosomal donor site. In contrast to Phe-tRNAPhe binding, Tyr-tRNATyr binding is impaired by the omission of the 50-S subunit, the replacement of GTP by its non-hydrolyzable analogs guanyl-5'-yl methylene diphosphonate and guanyl-5'-yl iminodiphosphonate, and also by the presence of the antibiotic streptogramin A. This suggests that the correct interaction of Tyr-tRNATyr with the peptidyl transferase centre is essential for the stability of this ligand on the ribosome. Moreover, the aminoglycoside antibiotics are also necessary, even after the binding reaction is complete, to maintain Tyr-tRNATyr on the ribosome.
Collapse
|
24
|
Girshovich AS, Bochkareva ES, Kurtskhalia TV, Pozdnyakov VA, Ovchinnikov YA. Binding of GTP to elongation factor G by photoaffinity labeling. Methods Enzymol 1979; 60:726-45. [PMID: 459926 DOI: 10.1016/s0076-6879(79)60068-x] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
25
|
Sprinzl M, Cramer F. The -C-C-A end of tRNA and its role in protein biosynthesis. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1979; 22:1-69. [PMID: 392600 DOI: 10.1016/s0079-6603(08)60798-9] [Citation(s) in RCA: 127] [Impact Index Per Article: 2.8] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
|
26
|
Belitsina NV, Glukhova MA, Spirin AS. Elongation factor G-promoted translocation and polypeptide elongation in ribosomes without GTP cleavage: use of columns with matrix-bound polyuridylic acid. Methods Enzymol 1979; 60:761-79. [PMID: 379541 DOI: 10.1016/s0076-6879(79)60070-8] [Citation(s) in RCA: 15] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
27
|
Kaziro Y. The role of guanosine 5'-triphosphate in polypeptide chain elongation. BIOCHIMICA ET BIOPHYSICA ACTA 1978; 505:95-127. [PMID: 361078 DOI: 10.1016/0304-4173(78)90009-5] [Citation(s) in RCA: 473] [Impact Index Per Article: 10.3] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
28
|
Lam KS, Heintz RL. Immobilization of reticulocyte elongation factor EF-2. EUROPEAN JOURNAL OF BIOCHEMISTRY 1978; 88:459-65. [PMID: 689031 DOI: 10.1111/j.1432-1033.1978.tb12470.x] [Citation(s) in RCA: 2] [Impact Index Per Article: 0.0] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/24/2022]
Abstract
Conditions are described whereby the ADP-ribosylation (from NAD+) of reticulocyte elongation factor EF-2, catalyzed by diphtheria toxin, is essentially complete and whereby the reverse of this process may be carried out with recovery of 60--70% of the original EF-2 activity. Both reactions proceed well at room temperature. The reverse reaction is much slower than the ADP-ribosylation process and requires high nicotinamide concentrations. For the reverse reaction to occur at a significant rate it is necessary to lower the pH to 6.5 (from the 7.5 used for the forward reaction). NAD+ covalently linked to agarose may replace NAD+ in the diphtheria toxin reaction. The characteristics of this reaction are similar to those of the reaction employing free NAD+ except that the velocity is reduced and the concentration of NAD+ moieties greatly increased. NAD+ immobilized on agarose through the C-8 of the adenine ring is a superior substrate compared with NAD+ linked to agarose via its periodate-oxidized ribose moieties. Preliminary experiments indicate that reversal of this latter reaction with recovery of biological activity may be possible.
Collapse
|
29
|
Fresno M, Vázquez D. Initiation of translation with native 40-S ribosomal subunits. EUROPEAN JOURNAL OF BIOCHEMISTRY 1978; 83:169-78. [PMID: 627208 DOI: 10.1111/j.1432-1033.1978.tb12081.x] [Citation(s) in RCA: 10] [Impact Index Per Article: 0.2] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/23/2022]
|
30
|
ANALYSIS OF RIBOSOMAL TRANSLOCATION BY DRUGS. Gene Expr 1978. [DOI: 10.1016/b978-0-08-022624-8.50014-4] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
|
31
|
Spirin AS. Energetics of the ribosome. PROGRESS IN NUCLEIC ACID RESEARCH AND MOLECULAR BIOLOGY 1978; 21:39-62. [PMID: 358279 DOI: 10.1016/s0079-6603(08)60266-4] [Citation(s) in RCA: 25] [Impact Index Per Article: 0.5] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
32
|
Girbes T, Campuzano S, Vźquez D, Modolell J. Effects of cations, antibiotics and other agents on the turnover of guanosine-nucleotide.elongation-factor-G.ribosome complexes. EUROPEAN JOURNAL OF BIOCHEMISTRY 1977; 81:483-90. [PMID: 340227 DOI: 10.1111/j.1432-1033.1977.tb11973.x] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|
33
|
Girbes T, Vázquez D, Modolell J. Detection of guanosine-nucleotide.elongation-factor-G complexes produced during the decay of guanosine-nucleotide.elongation-factor-G.Ribosome complexes. EUROPEAN JOURNAL OF BIOCHEMISTRY 1977; 81:473-81. [PMID: 340226 DOI: 10.1111/j.1432-1033.1977.tb11972.x] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 12/14/2022]
|