Occurrence in vivo of selenocysteyl-tRNA(SERUCA) in Escherichia coli. Effect of sel mutations

Journal Article · Thu Jun 15 00:00:00 EDT 1989 · J. Biol. Chem.; (United States)

OSTI ID:5934746

Leinfelder, W; Stadtman, T C; Boeck, A

The selC gene of Escherichia coli codes for a novel tRNA species which is aminoacylated by L-serine and is required for the insertion of selenocysteine into proteins. As a first step toward the elucidation of the postulated pathway for selenocysteine formation from an L-serine residue esterified to tRNA, we have examined whether an increase in the selC gene dosage allows the demonstration of selenocysteyl-tRNA formation in vivo. To this end, cells of an E. coli strain carrying selC on a multicopy plasmid were labeled with (/sup 75/Se)selenite, their tRNA was isolated and deacylated, and the hydrolysate was analyzed by thin layer chromatography and ion exchange chromatography. Both methods unequivocally demonstrated that the increase in the selC gene product concentration correlated with an augmented level of selenocysteine bound to tRNA. The formation of selenocysteine depended on the presence of functional products of the selA and selD genes but not of the selB gene. The selB gene product, therefore, may have a function in the decoding step itself.

• Research Organization: Lehrstuhl fuer Mikrobiologie der Universitaet, Muenchen (Germany, F.R.)
• OSTI ID: 5934746
• Journal Information: J. Biol. Chem.; (United States), Vol. 264:17
• Country of Publication: United States
• Language: English

Related Subjects

59 BASIC BIOLOGICAL SCIENCES
ESCHERICHIA COLI
GENE MUTATIONS
METALLOPROTEINS
BIOSYNTHESIS
RNA POLYMERASES
GENES
ACYLATION
BIOLOGICAL PATHWAYS
CYSTEINE
ION EXCHANGE CHROMATOGRAPHY
PLASMIDS
SELENIUM 75
SERINE
THIN-LAYER CHROMATOGRAPHY
TRACER TECHNIQUES
AMINO ACIDS
BACTERIA
BETA DECAY RADIOISOTOPES
CARBOXYLIC ACIDS
CELL CONSTITUENTS
CHEMICAL REACTIONS
CHROMATOGRAPHY
DAYS LIVING RADIOISOTOPES
ELECTRON CAPTURE RADIOISOTOPES
ENZYMES
EVEN-ODD NUCLEI
HYDROXY ACIDS
INTERMEDIATE MASS NUCLEI
ISOTOPE APPLICATIONS
ISOTOPES
MICROORGANISMS
MUTATIONS
NUCLEI
NUCLEOTIDYLTRANSFERASES
ORGANIC ACIDS
ORGANIC COMPOUNDS
ORGANIC SULFUR COMPOUNDS
PHOSPHORUS-GROUP TRANSFERASES
POLYMERASES
PROTEINS
RADIOISOTOPES
SELENIUM ISOTOPES
SEPARATION PROCESSES
SYNTHESIS
THIOLS
TRANSFERASES
550201* - Biochemistry- Tracer Techniques