Activities | Families | Sequences | Fold types | References | Help
B6db references: 2007584

type Journal Article
authors Forchhammer, K.; Leinfelder, W.; Boesmiller, K.; Veprek, B.; Bock, A.
title Selenocysteine synthase from Escherichia coli. Nucleotide sequence of the gene (selA) and purification of the protein
journal J Biol Chem
Activity 2.9.1.1
Family 2.9.1.1
sel selected
ui 2007584
year (1991)
volume 266
number 10
pages 6318-23
 
keywords Amino Acid Sequence
abstract The nucleotide sequence of the selA gene from Escherichia coli whose product is involved in the conversion of seryl-tRNA(Sec UCA) into selenocysteyl-tRNA(Sec UCA) was determined. selA codes for a polypeptide of a calculated Mr of 50,667; a protein of appropriate size was synthesized in vivo in a T7 promoter/polymerase system. An assay for SELA activity was devised which is based on the seryl-tRNA(Sec UCA)- dependent incorporation of [75Se] selenium into acid-insoluble material. It was used to follow SELA purification from cells that overproduced the protein from a phage T7 promoter plasmid. Purified native SELA protein migrates in gel filtration experiments with a native Mr of about 600,000. SELA contains 1 mol of bound pyridoxal 5- phosphate/mol of 50-kDa subunit. Evidence is presented that the overall conversion of seryl-tRNA(Sec UCA) to selenocysteyl-tRNA(Sec UCA) occurs at the SELA protein. SELA, therefore, has the function of a selenocysteine synthase.
last changed 2009/05/20 16:31

B6db references