Myocardial aminoacyl-transfer-ribonucleic acid synthetase and aminoacyl-transferring enzyme activity.
نویسندگان
چکیده
The properties of cytoplasmic aminoacyl-tRNA synthetase and aminoacyl-transferring enzymes in the myocardium were examined and methods for the assay of the activity of these enzyme systems were developed. Aminoacyl-tRNA synthetase activity was measured from the rate of incorporation of (14)C-labelled amino acid into aminoacyl-tRNA. Transferase activity was measured from the rate of incorporation of amino[(14)C]acyl-tRNA into protein in the presence of a standard preparation of hepatic ribosomes. Aminoacyl-tRNA synthetase activity is labile once the heart has been homogenized, whereas transferase activity is stable. The source of energy for synthetase activity is ATP; that for transferase is GTP. Transferase activity was inhibited by puromycin and stimulated by dithiothreitol, whereas synthetase activity was unaffected.
منابع مشابه
Role of isoleucyl-transfer ribonucleic acid synthetase in ribonucleic acid synthesis and enzyme repression in yeast.
Temperature-sensitive mutations in the isoleucyl-transfer ribonucleic acid (tRNA) synthetase of yeast, ilS(-)1-1 and ilS(-)1-2, were used to examine the role of aminoacyl-tRNA synthetase enzymes in the regulation of ribonucleic acid (RNA) synthesis and enzyme synthesis in a eucaryotic organism. At the permissive temperature, 70 to 100% of the intracellular isoleucyl-tRNA was charged in mutants ...
متن کاملPurification and properties of isoleucyl ribonucleic acid synthetase from Escherichia coli.
Aminoacyl ribonucleic acid formation is the first step in the translation of the genetic code for protein synthesis (1, 2). Although base pairing between the aminoacyl-RNA and the ribosome-bound messenger RNA may explain the mechanism of “reading” the messenger RNA base sequence, very little is known about how the transfer RNA structure is “read” by the activating enzymes. This, of course, is q...
متن کاملPurification and Properties of Isoleucyl Ribonucleic Acid Synthetase from Escherichia coZi*
Aminoacyl ribonucleic acid formation is the first step in the translation of the genetic code for protein synthesis (1, 2). Although base pairing between the aminoacyl-RNA and the ribosome-bound messenger RNA may explain the mechanism of “reading” the messenger RNA base sequence, very little is known about how the transfer RNA structure is “read” by the activating enzymes. This, of course, is q...
متن کاملMechanism of action of amino acid transfer ribonucleic acid ligases.
The first reaction in protein biosynthesis has been presumed to be the interaction of ATP, amino acid, and enzyme (amino acid-activating enzyme, aminoacyl transfer RNA ligase, tRNA synthetase) to form an enzyme-bound aminoacyl adenylic anhydride. Such aminoacyl anhydrides could react forward with hydroxylamine or with tRNA or backward with [““PI-PPi. Experiments, primarily involving inhibitors,...
متن کاملProtein synthesis during fungal spore germination. II. Aminoacyl-soluble ribonucleic acid synthetase activities during germination of Botryodiplodia theobromae spores.
The specific activities of 13 aminoacyl-soluble ribonucleic acid (sRNA) synthetases were measured at various time intervals during the germination of Botryodiplodia theobromae conidiospores. The enzyme activities were low or absent in ungerminated spores, and they increased rapidly as germination proceeded. When extracts of the ungerminated spores were prepared with mortar and pestle, very litt...
متن کاملذخیره در منابع من
با ذخیره ی این منبع در منابع من، دسترسی به آن را برای استفاده های بعدی آسان تر کنید
عنوان ژورنال:
- The Biochemical journal
دوره 126 2 شماره
صفحات -
تاریخ انتشار 1972