Biomaterial Database

Specific incorporation of selenium into lysine- and glutamate- accepting tRNAs from Escherichia coli. 1983

A J Wittwer

Amino acid transfer nucleic acids (tRNAs) that contain selenium-modified bases are synthesized by Escherichia coli in the presence of low levels (0.1-0.5 microM) of [75Se]selenite or [75Se]selenate. The amount of selenium incorporated (1-2 g atoms/100 mol of tRNA) was unchanged by 10-20-fold variations in selenium or sulfate concentrations or by the addition of 1 mM cysteine, sulfide, or sulfite. Specific incorporation of selenium (as opposed to nonspecific substitution for sulfur) was further indicated by the different reversed phase chromatographic elution patterns of 35S- and 75Se-labeled tRNAs isolated from cells labeled with 35SO2-4 and 75SeO2-4. Also, E. coli mutants unable to synthesize an abundant sulfur-modified base, 4-thiouracil, nevertheless produced normal levels of selenium-modified tRNAs. Two different methods of distinguishing between aminoacylated and nonaminoacylated tRNA, one which examined mobility during reversed phase chromatography and another which employed anti-AMP antibodies, indicated that over 50% of the selenium-containing tRNA had lysine or glutamate acceptor activity.

UI	MeSH Term	Description	Entries
D007700	Kinetics	The rate dynamics in chemical or physical systems.
D009154	Mutation	Any detectable and heritable change in the genetic material that causes a change in the GENOTYPE and which is transmitted to daughter cells and to succeeding generations.	Mutations
D011868	Radioisotopes	Isotopes that exhibit radioactivity and undergo radioactive decay. (From Grant & Hackh's Chemical Dictionary, 5th ed & McGraw-Hill Dictionary of Scientific and Technical Terms, 4th ed)	Daughter Isotope,Daughter Nuclide,Radioactive Isotope,Radioactive Isotopes,Radiogenic Isotope,Radioisotope,Radionuclide,Radionuclides,Daughter Nuclides,Daugter Isotopes,Radiogenic Isotopes,Isotope, Daughter,Isotope, Radioactive,Isotope, Radiogenic,Isotopes, Daugter,Isotopes, Radioactive,Isotopes, Radiogenic,Nuclide, Daughter,Nuclides, Daughter
D004926	Escherichia coli	A species of gram-negative, facultatively anaerobic, rod-shaped bacteria (GRAM-NEGATIVE FACULTATIVELY ANAEROBIC RODS) commonly found in the lower part of the intestine of warm-blooded animals. It is usually nonpathogenic, but some strains are known to produce DIARRHEA and pyogenic infections. Pathogenic strains (virotypes) are classified by their specific pathogenic mechanisms such as toxins (ENTEROTOXIGENIC ESCHERICHIA COLI), etc.	Alkalescens-Dispar Group,Bacillus coli,Bacterium coli,Bacterium coli commune,Diffusely Adherent Escherichia coli,E coli,EAggEC,Enteroaggregative Escherichia coli,Enterococcus coli,Diffusely Adherent E. coli,Enteroaggregative E. coli,Enteroinvasive E. coli,Enteroinvasive Escherichia coli
D012346	RNA, Transfer, Amino Acyl	Intermediates in protein biosynthesis. The compounds are formed from amino acids, ATP and transfer RNA, a reaction catalyzed by aminoacyl tRNA synthetase. They are key compounds in the genetic translation process.	Amino Acyl tRNA,Transfer RNA, Amino Acyl,tRNA-Amino Acyl,Amino Acyl T RNA,Acyl tRNA, Amino,Acyl, tRNA-Amino,tRNA Amino Acyl,tRNA, Amino Acyl
D012643	Selenium	An element with the atomic symbol Se, atomic number 34, and atomic weight 78.97. It is an essential micronutrient for mammals and other animals but is toxic in large amounts. Selenium protects intracellular structures against oxidative damage. It is an essential component of GLUTATHIONE PEROXIDASE.	Selenium-80,Selenium 80
D013045	Species Specificity	The restriction of a characteristic behavior, anatomical structure or physical system, such as immune response; metabolic response, or gene or gene variant to the members of one species. It refers to that property which differentiates one species from another but it is also used for phylogenetic levels higher or lower than the species.	Species Specificities,Specificities, Species,Specificity, Species