Open AccessSubstrate Properties of Yeast tRNA Phe Oxidized and Reduced at the 3′‐Terminal Ribose
Author(s) -
Haar Friedrich,
Schlimme Eckhard,
GómezGuillen Manuel,
Cramer Friedrich
Publication year - 1971
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1971.tb19685.x
Subject(s) - aminoacylation , transfer rna , substrate (aquarium) , ribose , yeast , chemistry , hydrolysis , enzyme , biochemistry , stereochemistry , nucleotide , transferase , rna , biology , ecology , gene
Native yeast tRNA Phe and this tRNA Phe with the 3′‐terminal AMP removed were oxidized by NaIO 4 and subsequently reduced by NaBH 4 . The following investigations were undertaken with these substrates: aminoacylation in borate buffer and measurement of the life‐time of the aminoacylated oxidized an reduced tRNA, hydrolysis with snake‐venom phosphodiesterase and pyrophosphorolysis with tRNA nucleotidyl transferase. Whereas the oxidized and reduced yeast tRNA Phe is a good substrate for the enzymes investigated, the corresponding tRNA Phe with the 3′‐terminal AMP removed is a very poor, if any, substrate in these reactions. From the data obtained and from proton‐magnetic‐resonance investigations with oxidized and reduced AMP and ATP it is concluded that the removal of the C2′—C3′ bond and introduction of two hydrogen atoms instead distorts the original ribose conformation at the 3′‐terminus. Under the assumption that this distortion is different for C 75 and A 76 the difference in reactivity between the two oxidized and reduced tRNAs can be explained.