5S rRNA binding proteins from the hyperthermophilic archaeon, Pyrococcus furiosus

A determination was made of the nucleotide sequence of the 2719 bp region o f a ribosomal protein gene cluster (PfeL32-PfeL19-PfL18-PfS5-PfL30) contain ing a 5S rRNA binding protein L18 homolog of hyperthermophilic archaea Pyro coccus furiosus. The organization of the archaeal ribosomal protein gene cl uster is similar to that in the spc-operon of Escherichia coli (L6-L18-S5-L 30-L15) but has two additional genes, namely those encoding PfeL32 and PfeL 19, which were identified as extra proteins that are apparently not present in bacterial E. coli. Using an inducible expression system, P. furiosus ma ture PfL18 protein and a mutant PfL18 with the basic N-terminal amino acid region deleted were produced in large amounts in E. coli and Northwestern a nalysis showed the N-terminal region of PfL18, including the conserved argi nine-rich region, to have a significant role in 5S rRNA-PfL18 interaction. (C) 2000 Federation of European Biochemical Societies. Published by Elsevie r Science B.V. All rights reserved.