Partial purification and characterization of seleno-tRNA biosynthetic enzyme(s)

Conference · Mon Mar 11 04:00:00 EST 1991 · FASEB Journal (Federation of American Societies for Experimental Biology); (United States)

OSTI ID:5374612

Politino, M; Veres, Z; Tsai, L; Stadtman, T C ^[1]

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1. National Inst. of Health, Bethesda, MD (United States)

up Selenium modification of tRNA has been previously demonstrated in broken cell preparations from Methanococcus vannielii and Salmonella typhimurium. Chromatography of the extracts from these bacteria on phenyl Sepharose yielded active enzyme(s) which eluted at 0.2 M (NH{sub 4}){sub 2}SO{sub 4}. Added E. coli bulk tRNA was used as substrate. Consistent with the results obtained from the broken cell preparations, ARP and o-acetyl serine were required for full activity. Dilution of {sup 75}Se incorporated into the tRNA by unlabeled L-selenocysteine suggests that this amino acid may serve as the selenium donor. RPC-5 chromatography of the {sup 75}Se-labeled tRNA products revealed two major radioactive tRNA peaks eluting at 0.6 M and 0.8 M NaCl. Fractionation of E. coli bulk tRNA by RPC-5 chromatography prior to addition to the assay demonstrated that for S. typhimurium the tRNA eluting at 0.6 M and 0.8 M NaCl could serve as a substrate with the 0.8 M fraction exhibiting the highest specific activity. Nucleoside analysis of the labeled tRNA mixtures revealed two as yet unidentified radioactive peaks on the HPLC profile.

• OSTI ID: 5374612
• Report Number(s): CONF-9104107--
• Conference Information: Journal Name: FASEB Journal (Federation of American Societies for Experimental Biology); (United States) Journal Volume: 5:4
• Country of Publication: United States
• Language: English

Related Subjects

560300* -- Chemicals Metabolism & Toxicology
63 RADIATION, THERMAL, AND OTHER ENVIRON. POLLUTANT EFFECTS ON LIVING ORGS. AND BIOL. MAT.
AMINO ACIDS
BACTERIA
BETA DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CHEMICAL COMPOSITION
CHROMATOGRAPHY
CYSTEINE
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ELEMENTS
ENZYME ACTIVITY
ENZYMES
EVEN-ODD NUCLEI
FRACTIONATION
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
LIQUID COLUMN CHROMATOGRAPHY
METABOLISM
MICROORGANISMS
NUCLEI
NUCLEIC ACIDS
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PROTEINS
RADIOISOTOPES
RNA
SELENIUM
SELENIUM 75
SELENIUM ISOTOPES
SEMIMETALS
SEPARATION PROCESSES
THIOLS
TRACER TECHNIQUES
TRANSFER RNA