On the role of intracellular potassium in protein synthesis

Lubin, Martin; Ennis, Herbert L.

doi:10.1016/0926-6550(64)90306-8

Cited by 139 publications

(103 citation statements)

References 19 publications

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“…A similar effect of NH,+ in vivo was observed by Rigano 8z Violante (I 973) during derepression of nitrate reductase synthesis by Cyanidium caldarium. Ammonium ions stimulate cell-free amino acid incorporation (Lubin & Ennis, 1964) ; high NH$ concentrations are required for ribosomal stability in vitro (Hartman, Nolan & Amaya, 1971) and for the peptidyl transferase reaction (Miskin, Zamir & Elson, 1970). Under argon, only a limited amount of nitrogenase was derepressed, as previously observed by Parejko & Wilson, 1970; Casamino acids added prior to derepression increased the final activity obtained in one instance.…”

Section: Discussionsupporting

confidence: 60%

Control of Nitrogenase Synthesis in Klebsiella pneumoniae

Tubb

Postgate

1973

Journal of General Microbiology

103

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SUMMARYSulphate-limited continuous cultures of Klebsiella pneumoniae showed a proportional repression of nitrogenase activity with increasing concentrations of ammonium ion in the influent medium. A fully repressed population had a 50 % greater bacterial density than a fully derepressed one. On derepression, synthesis of nitrogenase lagged for 90 min after exhaustion of NH,+ from the medium but was complete within one doubling time. Casamino acids did not decrease the prefixation lag obtained under sulphate-limited conditions in the chemostat. Longer lags were obtained when NH,+ was exhausted under N-limited conditions. Such lags were decreased by Casamino acids, yeast extract, or L-aspartate. Aspartate-N completely repressed nitrogenase under sulphate-or carbon-limited conditions but not under nitrogen limitation. In the initial stages of repression of nitrogenase synthesis by NH,+, apparent production of active enzyme continued for a short time in the absence of protein synthesis de novo; nitrogenase was then diluted out as the organisms multiplied. Repression by NH,+ was at the level of mRNA transcription according to studies with rifampicin and chloramphenicol. ' Coding capacity' for nitrogenase synthesis declined with a half-life of about 4.5 min following inhibition of RNA synthesis with rifampicin. NH,+ did not influence the decay rate but stimulated translation of such nitrogenase-specifying mRNA as had been initiated.

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Section: Discussionsupporting

confidence: 60%

Control of Nitrogenase Synthesis in Klebsiella pneumoniae

Tubb

Postgate

1973

Journal of General Microbiology

103

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“…The NH4+ according to Nakamoto et al (12). Similar obqervations have been made by Ltubin and Ennis (11). The binding of amino acyl-sRAX to the complex of mRNA and ribosomes from ral)bit retictulocytes requtires K+, GTP, and 2 soluble enzyme fractions (1).…”

mentioning

confidence: 69%

Effects of Univalent Cations on the Inductive Formation of Nitrate Reductase

Nitsos¹,

Evans²

1966

Plant Physiol.

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“…Peptidyl transfer in our two systems and protein synthesis in the E. coli system in vitro display similar specificities towards divalent [ 141 and monovalent [15] cations except for the inactivity of Ca2+ and NH,+ in the P-met-oligonucleotide system. Protein synthesis is, however, more restrictive towards concentration of both mono and divalent cations than either of our puromycin reaction systems, presumably because of its greater complexity, and the need to satisfy the requirements of several different reactions.…”

Section: Formyl-methionyl-oligonucleotide Systemmentioning

confidence: 88%

Ribosome‐Catalyzed Peptidyl Transfer

Maden

Monro²

1968

European Journal of Biochemistry

138

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Effects of cations and pH value on ribosome-catalyzed peptidyl transfer were studied, using as assays the reaction of puromycin with (a) washed, polyphenylalanine-charged Escherichia coli ribosomes and (b) terminal fragments from formlyl-methionyl-tRNA (CAACCA-Met-F and CCA-Met-F) in the presence of purified 50 S ribosomal subunits. I n both systems the reaction required the presence of suitable divalent and monovalent cations, and was progressively inhibited below pH 8.5.I n the polyphenylalanine system Mg2+ was active over the range 0.3 mM to 1 M, with a broad optimum from approximately 3 to 100 mM. Mg2+ was replaceable by Ca2+ or Mn2+. Other divalent metal ions were inert or inhibitory. Spermidine was also inert. Monovalent cations were active in the order, NH,+ > K+ = Rb+ > Cs+. NH,+ and K+ were progressively more effective from 10 mM to a t least 1 M. Na+ and Li+ were inert.The reaction of formyl-methionyl oligonucleotides with puromycin showed similar responses to the polyphenylalanine system except that (a) Mg2+ was active over the range 5 mM to 1 M with an optimum a t approximately 100 mM, (b) Ca2+ was inert, (c) K+ was inactive below 100 mM, and (d) NH,+ was only weakly active.The bearing of the results on the mechanism of ribosome-catalyzed peptidyl transfer is discussed, and a possible application of the results is noted.A considerable body of evidence now indicates that peptide bond formation in protein synthesis is catalysed by the 50 S ribosomal subunit ([l] and references therein). Moreover the reaction possesses properties of a simple group transfer reaction, and has been named peptidyl transfer [l]. As an approach toward furthering our understanding of the reaction mechanism and as part of a more general study of the reaction, we have examined in some detail the effects of cations and pH value on ribosome-catalyzed peptidyl transfer.Two assay systems have been employed in the present study, the reaction of puromycin with washed, polyphenylalanine-charged E. coli ribosomes [ l ] and the 50 S ribosome-catalyzed reaction of puromycin with formyl-methionyl-oligonucleotide fragments (CAACCA-Met-P and CCA-Met-F) from formyl-methionyl-tRNA [2 -41. The polyphenylalanine system has the advantage that polyphenylalanyl-tRNA, once synthesized, remains firmly bound to the (50 S) ribosome under a wide variety of ionic conditions, including exposure to low Mg2+ concentration and to absence of monovalent cations [5]. The ionic characteristics of peptidyl transfer can therefore be distinguished from those of the other Unusual Abbreviations. F-met (or met-I?), N-formylmethionyl; mRNA, messenger RNA; tRNA, transfer RNA ; BBOT, 2 : 5 bis [5-tertiary-butyl-benzoxazolyl-2-]thiophen (purchased from CIBA). 21.steps of protein synthesis, such as binding of mRNA and tRNA, and interaction between 50 S and 30 S subunits. I n the reaction of F-met-oligonucleotides with puromycin the oligonucleotides are not in the form of a pre-existing complex with the 50s ribosome, but the reaction is more resolved than that in the polyph...

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On the role of intracellular potassium in protein synthesis

Cited by 139 publications

References 19 publications

Control of Nitrogenase Synthesis in Klebsiella pneumoniae

Control of Nitrogenase Synthesis in Klebsiella pneumoniae

Effects of Univalent Cations on the Inductive Formation of Nitrate Reductase

Ribosome‐Catalyzed Peptidyl Transfer

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