Synthesis of 2-thio-5-carboxymethyluridine methyl ester: a component of transfer RNA

1969 ◽  
Vol 47 (12) ◽  
pp. 1202-1203 ◽  
Author(s):  
L. Baczynskyj ◽  
K. Biemann ◽  
Maurice H. Fleysher ◽  
Ross H. Hall
Keyword(s):  
Methyl Ester ◽  
Transfer Rna ◽  
Yeast Trna ◽  
Mercuric Salt

2-Thio-5-carboxymethyluridine methyl ester was synthesized by condensing the mercuric salt of 2-thio-5-carboxymethyluracil methyl ester with 2,3,5-tri-O-benzoyl-D-ribosyl chloride. The product is identical to a nucleoside isolated from yeast tRNA

Selective Labelling of the Methyl Carboxylate Substituents Found in the Anticodon Sequences of Some Species of Yeast Transfer RNA

1975 ◽  
Vol 53 (1) ◽  
pp. 1-10 ◽  
Author(s):  
T. D. Kennedy ◽  
B. G. Lane
Keyword(s):  
Methyl Ester ◽  
Room Temperature ◽  
Methyl Esters ◽  
Transfer Rna ◽  
Wheat Embryo ◽  
Yeast Trna ◽  
Selective Labelling

(1) By incubation in 0.1 M NaOH for 10 min at room temperature, it is possible to "saponify" some of the methyl carboxylate linkages in bulk yeast tRNA. By incubation with S-adenosyl[Me-14C]methionine and either homologous (yeast) or heterologous (wheat-embryo) enzymes, it is then possible to "re-esterify" the "saponified" tRNA and thereby effect selective labelling at 5-carboxymethyluridine [Me-14C]methyl ester residues. (2) There is also selective labelling at 2-thio-5-carboxymethyluridine [Me-14C]methyl ester residues when "saponified" yeast tRNA is incubated with S-adenosyl[Me-14C]methionine and homologous (but not heterologous) enzymes. (3) When selectively labelled yeast tRNA is hydrolyzed by RNase T1, both 5-carboxymethyluridine [Me-14C]methyl ester and its 2-thio-analogue are released as part of large oligonucleotides, each of which contains roughly 10 nucleotide residues. (4) There are at least three, and possibly four [Me-14C]-methyl ester-containing oligonucleotides released by RNase T1 digestion of selectively labelled "saponified" yeast tRNA. A comparison of the chromatographic properties of the different [Me-14C]oligonucleotides suggests that the same 5-carboxymethyluridine residues are probably targets for both homologous and heterologous enzymes. (5) The properties of the selectively labelled oligonucleotides are consistent with the view that some of them probably are derived from yeast tRNA3Glu, tRNA2Lys, and tRNA3Arg, ail of which are known to contain 5-carboxymethyl methyl esters as part of their anticodon sequences.

Wheat Embryo Ribonucleates. V. Generation of N2-Dimethylgnanylate When 'Fully Sequenced' Homogeneous Species of Transfer RNA are Used as Substrates for Wheat Embryo Methyltransferases

1975 ◽  
Vol 53 (6) ◽  
pp. 690-697 ◽  
Author(s):  
T. C. Kwong ◽  
B. G. Lane
Keyword(s):  
Molecular Basis ◽  
Transfer Rna ◽  
Target Site ◽  
Common Site ◽  
Tertiary Structures ◽  
Wheat Embryo ◽  
E Coli ◽  
Yeast Trna ◽  
The Subject ◽  
Random Distributions

1. When S-adenosyl[methyl-14C]methiomne and various species of transfer RNA are used as substrates for wheat embryo methyltransferases, the principal site of guanylate-N2 methylation can be shown to be a G-residue between the stems of the dihydrouridine and anticodon loops. This common site of guanylate-N2 methylation is referred to as the interstem target site.2. When the interstem target site is the non-terminal G-residue in a G-C-G-C sequence, as in the cases of Escherichia coli tRNA1Leu, tRNAIle, and tRNA3Ser, there is preponderant dimethylation to yield N2-dimethylguanylate.3. When the interstem target site is part of a U-C-G-U sequence, as in the case of E. coli tRNAtMet, there is diminished dimethylation and correspondingly increased monomethylation to yield N2-monomethylguanylate.4. When the interstem target site is the non-terminal G-residue in an A-U-G-G sequence, as in the case of yeast tRNAAsp, there is negligible dimethylation and almost exclusive monomethylation to yield N2-monomethylguanylate.5. The concerted way in which the primary, secondary, and tertiary structures of tRNA molecules might influence the efficacy of these methylations is the subject of a brief discussion. Attention is also focused on the evolutionary and molecular basis for the generally non-random distributions of methylated oligonucleotide sequences in ribosomal and transfer ribonucleates.

The Effect of Some Synthetic Arginyl and Lysyl Compounds on Clotting and Fibrinolysis

1972 ◽  
Vol 28 (02) ◽  
pp. 289-298 ◽  
Author(s):  
M. J Weinstein ◽  
R. F Doolittle
Keyword(s):  
Methyl Ester ◽  
Thrombin Activation

SummaryThe effects of a number of synthetic arginyl- and lysyl-compounds on clotting and fibrinolysis have been studied. The lysyl derivatives had no significant effect on the clotting of recalcified plasma or recalcified euglobulin preparations, but tosyllysine (TL) and tosyllysine methyl ester (TLME) were very effective inhibitors of fibrinolysis. Certain arginyl-peptides (in particular, tosylarginylsarcosine methyl ester) were very effective at delaying clotting in these systems. These same substances gave rise to an exaggerated thrombin production, however, evidently by interfering with the natural thrombin activation of plasma antithrombin(s).

Activity of Plasmin and Streptokinase-Activator on Substituted Arginine and Lysine Esters

1966 ◽  
Vol 16 (01/02) ◽  
pp. 018-031 ◽  
Author(s):  
S Sherry ◽  
Norma Alkjaersig ◽  
A. P Fletcher
Keyword(s):  
Molecular Structure ◽  
Methyl Ester ◽  
Comparative Studies ◽  
Esterase Activity ◽  
Methyl Esters ◽  
Hydrolytic Activity ◽  
The Other ◽  
Other Hand

SummaryComparative studies have been made of the esterase activity of plasmin and the streptokinase-activator of plasminogen on a variety of substituted arginine and lysine esters. Human plasmin preparations derived by different methods of activation (spontaneous in glycerol, trypsin, streptokinase (SK) and urokinase) are similar in their esterase activity; this suggests that the molecular structure required for such esterase activity is similar for all of these human plasmins. Bovine plasmin, on the other hand, differs from human plasmin in its activity on several of the substrates studied (e.g., the methyl esters of benzoyl arginine and tosyl, acetyl and carbobenzoxy lysine), a finding which supports the view that molecular differences exist between the two animal plasmins. The streptokinase-activator hydrolyzes both arginine and lysine esters but the ratios of hydrolytic activity are distinct from those of plasmin and of other activators of plasminogen. The use of benzoyl arginine methyl ester as a substrate for the measurement of the esterase activity of the streptokinase-activator is described.

Sign in / Sign up

Export Citation Format

Share Document