Amber mutations in ribosome recycling factors of Escherichia coli and Thermus thermophilus: evidence for C-terminal modulator element.
Ribosome recycling factor, referred to as RRF, is essential for bacterial growth because of its activity of decomposition of the post-termination complex of the ribosome after release of polypeptides. In this study, we isolated a conditionally lethal amber mutation, named frr-3, in the Escherichia coli RRF gene at amino acid position 161, showing that the truncation of the C-terminal 25 amino acids of RRF is lethal to E. coli. An RRF gene cloned from Thermus thermophilus, whose protein is 44% identical and 68% similar to E. coli RRF, failed to complement the frr-3(Am) allele. However, truncation of the C-terminal five amino acids conferred intergeneric complementation activity on T. thermophilus RRF, demonstrating the modulator activity of the C-terminal tail. Rapid purification of T. thermophilus RRF was achieved by T7-RNA polymerase-driven overexpression for crystallography.
Fujiwara
T
T
Department of Tumor Biology, The Institute of Medical Science, The University of Tokyo, Takanawa, Japan.
Ito
K
K
Nakayashiki
T
T
Nakamura
Y
Y
D000595:Amino Acid Sequence; D001426:Bacterial Proteins / Q000235:genetics* / Q000378:metabolism*; D001483:Base Sequence; D003001:Cloning, Molecular; D017931:DNA Primers / Q000235:genetics; D004269:DNA, Bacterial / Q000235:genetics; D004926:Escherichia coli / Q000235:genetics* / Q000378:metabolism*; D005798:Genes, Bacterial; D005816:Genetic Complementation Test; D008969:Molecular Sequence Data; D009154:Mutation; D011506:Proteins / Q000235:genetics* / Q000378:metabolism*; D012269:Ribosomal Proteins; D012270:Ribosomes / Q000378:metabolism*; D013045:Species Specificity; D016963:Thermus thermophilus / Q000235:genetics* / Q000378:metabolism*
D001426:Bacterial Proteins; D017931:DNA Primers; D004269:DNA, Bacterial; D011506:Proteins; D012269:Ribosomal Proteins; C087267:ribosome releasing factor