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Showing papers on "Ribosomal protein published in 1969"



Journal ArticleDOI
26 Apr 1969-Nature
TL;DR: The streptomycin locus of E. coli specifies a 30S ribosomal protein which determines the sensitivity of the 30S subunit to strePTomycin and streptomecin induced errors of translation.
Abstract: The streptomycin locus of E. coli specifies a 30S ribosomal protein which determines the sensitivity of the 30S subunit to streptomycin and streptomycin induced errors of translation.

435 citations



Journal ArticleDOI
TL;DR: The ability of rat muscle ribosomal subunits to combine with subunits of other 80 s ribosomes was determined by density-gradient analysis and by estimation of polyuridylic acid-directed polypeptide synthesis, and both hybrids formed and were active when rat muscle and rat liver subunits were combined.

152 citations


Journal ArticleDOI
05 Dec 1969-Science
TL;DR: The 30S ribosomal proteins of strains of Escherichia coli sensitive to and dependent on streptomycin are compared and a single protein is identified that is functionally altered in the ribosomes dependent on Streptomytin.
Abstract: We have compared the 30S ribosomal proteins of strains of Escherichia coli sensitive to and dependent on streptomycin and identified a single protein that is functionally altered in the ribosomes dependent on streptomycin. This protein (30S-15) is the same protein that is functionally altered in ribosomes resistant to streptomycin.

133 citations


Journal ArticleDOI
04 Jul 1969-Science
TL;DR: Reconstitution of active particles in the presence of isolated split proteins allowed the identification of the single split protein responsible for spectinomycin sensitivity.
Abstract: Reconstitution of 30S ribosomal particles from 16S ribosomal RNA and total proteins, or from core proteins and split proteins obtained from the ribosomes of strains of Escherichia coli sensitive to and resistant to spectinomycin, shows that the split protein fraction determines the response of polypeptide synthesis in virto to spectinomycin. Reconstitution of active particles in the presence of isolated split proteins allowed the identification of the single split protein responsible for spectinomycin sensitivity.

126 citations



Journal ArticleDOI
TL;DR: The protein compositions and 5 s RNA contents of the nascent ribosomal particles are compared with those of protein-deficient particles obtained by exposing 50 s Ribosomal subunits to a concentrated LiCl solution and the molecular compositions are found to be similar, but not exactly the same.

66 citations


Journal ArticleDOI
TL;DR: The data lend strong support to the hypothesis that inhibition of mitochondrial protein synthesis is the biochemical basis for reversible bone marrow depression from chloramphenicol.

65 citations


Journal ArticleDOI
TL;DR: It is concluded that the conformation of the ribosome is an important factor in determining the detachment of ribosomal proteins by salt and that electrostatic forces have a major role in binding virtually all of the ribsomal proteins to the Ribosomal RNA.

63 citations


Journal ArticleDOI
25 Jan 1969-Nature
TL;DR: This work has demonstrated that the initiation of protein synthesis requires messenger RNA, formyl-methionyl-tRNA, ribosomes, GPT7–9, and at least three protein initiation factors, and Native ribosomal subunits have been shown to contain the initiation factors.
Abstract: PREVIOUS work has demonstrated that the initiation of protein synthesis requires messenger RNA (mRNA)1–3, formyl-methionyl-tRNA (F-met-tRNA)4–6, ribosomes, GPT7–9, and at least three protein initiation factors10–12. Native ribosomal subunits have been shown to contain the initiation factors, and such subunits are extremely active in the initiation of protein synthesis13.


Journal ArticleDOI
TL;DR: It is concluded that at least these ten ribosomal proteins are synthesized and accumulated co-ordinately with Ribosomal RNA.

Journal ArticleDOI
TL;DR: The translation time of an average cell protein appears relatively uninfluenced by the presence or absence of growth per se, and many N-termini of cell proteins are stably formylated, and can be isolated intact from cell protein more than a generation after synthesis.

Journal ArticleDOI
TL;DR: Diabetes did not produce a detectable alteration in the electrophoretic pattern of skeletal muscle ribosomal proteins, and the pattern of bands was the same as with proteins from liver ribosomes.

Journal ArticleDOI
TL;DR: New experimental results that show the highly cooperative nature of the assembly reaction are described; the number of sites, per RNA chain, which can bind ribosomal proteins independently from each other is at most two to three.
Abstract: Functionally active 30S ribosomes can be reconstituted in vitro from 16S RNA and a mixture of 30S ribosomal proteins under certain defined conditions. Our previous studies on the specificity and kinetics of reconstitution are summarized and discussed. The reconstitution reaction is first-order with respect to formation of active 30S ribosomes. The rate-limiting reaction is probably unimolecular, and it represents the structural rearrangement of an intermediate. Presumed reconstitution intermediates, or RI particles, have been isolated from reconstitution mixtures incubated at low temperature. It has been concluded that the reconstitution takes place in stepwise fashion: 16S ribosomes. New experimental results that show the highly cooperative nature of the assembly reaction are described; the number of sites, per RNA chain, which can bind ribosomal proteins independently from each other (i.e., without cooperativity) is at most two to three. Finally, another approach to the study of ribosome assembly in vivo is described. It utilizes cold-sensitive E. coli mutants that are defective in ribosome biosynthesis at low temperature and accumulate incomplete “intermediate” ribosomal particles.

Journal ArticleDOI
TL;DR: It is suggested that different cystron(s) direct the synthesis of the ribosomal proteins in the two ribosome classes, which are electrophoretically dissimilar from those extracted in a similar manner from cytoplasmic ribosomes.


Journal ArticleDOI
TL;DR: The sedimentation coefficient is not a reliable indicator of the amount or kind of proteins present in particles, and cannot be used as the sole basis for characterizing particles or comparing different particles.

Journal ArticleDOI
TL;DR: Comparison of electrophoretic patterns of ribosomal proteins from NH(4)Cl-washed and unwashed ribosomes and F(2), at pH 4.5, shows that F( 2) corresponds to the slowest-moving component of the proteins derived from unwashed Ribosomes.
Abstract: Previous work has shown that F2, one of several ribosomal factors involved in polypeptide chain initiation, functions in the binding of formylmethionyl-transfer RNA (fMet ∼ tRNAf) to a messenger RNA-ribosome complex. F2 was isolated from 1.0 M ammonium chloride washes of E. coli Q13 ribosomes as a protein homogeneous on polyacrylamide gel electrophoresis at both pH 4.5 and 7.8. Its molecular weight is approximately 80,000. Comparison of electrophoretic patterns of ribosomal proteins from NH4Cl-washed and unwashed ribosomes and F2, at pH 4.5, shows that F2 corresponds to the slowest-moving component of the proteins derived from unwashed ribosomes. This component is missing from the NH4Cl-washed ribosomes. The activity of F2 is stimulated by two additional factors, initiation factor F1 and a factor(s) present in a narrow ammonium sulfate fraction of the ribosomal NH4Cl wash. The nature of the latter is unknown.

Journal ArticleDOI
TL;DR: Results show that cistrons for 30S proteins of E. coli can replace those of S. typhosa in the Salmonella genome and in a diploid hybrid with aSalmonella endogenote and an E. bacteria exogenote, both sets of cistron are expressed.
Abstract: Intergeneric mating between Escherichia coli and Salmonella typhosa was used to locate at least three 30S ribosomal proteins near the streptomycin locus in the region of 54 to 66 min of the E. coli map. This procedure utilizes differences in the electrophoretic patterns of 30S ribosomal protein of the parents. The results show that cistrons for 30S proteins of E. coli can replace those of S. typhosa in the Salmonella genome. Moreover, in a diploid hybrid with a Salmonella endogenote and an E. coli exogenote, both sets of cistrons are expressed.

Journal ArticleDOI
TL;DR: Spectinomycin resistant (spcr) mutants obtained by treating the cells of E. coli K12, W3637 with nitrosoguanidine were found to contain the altered 30-4 protein component, while no difference was detected in 50s ribosomal proteins between spcr and spcs bacteria.
Abstract: SummarySpectinomycin resistant (spcr) mutants were obtained by treating the cells of E. coli K12, W3637 with nitrosoguanidine. The compositions of ribosomal proteins were analyzed for six out of eleven such spcr-mutants with chromatography on a carboxymethyl cellulose (CMC) column. The 30s ribosomal subunit from all of the spcr-mutants was found to contain the altered 30-4 protein component, while no difference was detected in 50s ribosomal proteins between spcr and spcs bacteria.

Journal ArticleDOI
TL;DR: The p-fluorophenylalanine containing ribosomes have normal physicalchemical properties with respect to dissociation into sub-units by dialysis against low Mg++ concentration, sedimentation values in sucrose gradients and buoyant density in isopycnic CsCl gradients.
Abstract: The effect of actinomycin D and dl-p-fluorophenylalanine on ribosome formation has been studied in exponentially growing Tetrahymena cells. Both compounds cause inhibition of ribosome formation. However, ribosome formation is qualitatively very similar in inhibited and uninhibited cells. p-Fluorophenylalanine is incorporated into ribosomal proteins of completed ribosomal particles when used in inhibitor concentration (1 mg/ml). This demonstrates that limited modifications of ribosomal proteins, due to the presence of the amino acid analogue in the ribosomal polypeptide chains still allow the modified proteins to assemble with ribosomal RNA to give intact ribosomal particles. The p-fluorophenylalanine containing ribosomes have normal physicalchemical properties with respect to dissociation into sub-units by dialysis against low Mg++ concentration, sedimentation values in sucrose gradients and buoyant density in isopycnic CsCl gradients. The regulatory aspects of ribosome biosynthesis in the light of the present results are discussed.

Journal ArticleDOI
TL;DR: A new technique for the isolation of single proteins from complex protein mixtures by means of electrophoresis in polyacrylamide gels is described, which allows the resolution of multicomponent mixtures containing a variety of proteins which differ partly only slightly in electrophoretic mobility from each other.



Journal ArticleDOI
TL;DR: The state of the rel locus affects not only the synthesis of ribosomal RNA under amino acid starvation, but also the synthesized ribosome protein during recovery from amino acids starvation.

Journal ArticleDOI
TL;DR: The amino acid composition of these fractions and of the total protein mixture are basically similar but there are also significant differences with regard to some amino acids.
Abstract: Total ribosomal protein from rat liver ribosomes can be separated into about 20 chief electrophoretic fractions by preparative polyacrylamide gel electrophoresis. Ten electrophoretically homogeneous fractions have been isolated from the total mixture of ribosomal protein, respectively from proteins, prefractionated by CM-cellulose chromatography. Amino acid composition and molecular weights of some fractions have been determined. The amino acid composition of these fractions and of the total protein mixture are basically similar but there are also significant differences with regard to some amino acids. The molecular weights of the proteins studied are in the range between 7,000 and 29,000.

Journal ArticleDOI
TL;DR: There appears to be a pool of ribosomal proteins in non-proliferating rat liver and in the slow growing hepatoma which is sufficient to support ribosome synthesis for at least 1 h and the results suggest that this feed-back control, which may involve monomeric ribosomes, acts at a post-transcriptional step.

Journal ArticleDOI
TL;DR: Evidence is provided that four proteins were preferentially synthesized and assembled into 50 s subunits early during recovery from chloramphenicol treatment and that considerable variation occurred in the rate of assembly of the various proteins into 50S subunits.