Open AccessDifferent conformational forms of Escherichia coli and rat liver 5S rRNA revealed by Pb(II)‐induced hydrolysis
Author(s) -
CIESIOLKA Jerzy,
LORENZ Siegfried,
ERDMANN Volker A.
Publication year - 1992
Publication title -
european journal of biochemistry
Language(s) - English
Resource type - Journals
eISSN - 1432-1033
pISSN - 0014-2956
DOI - 10.1111/j.1432-1033.1992.tb16671.x
Subject(s) - hydrolysis , rna , nucleotide , atp hydrolysis , crystallography , helix (gastropod) , ribosomal rna , chemistry , escherichia coli , stereochemistry , biochemistry , biology , enzyme , gene , ecology , atpase , snail
Different stable forms of Escherichia coli and rat liver 5S rRNA have been probed by Pb(II)‐induced hydrolysis. In the native A forms of 5S rRNA, Pb 2+ reveal single‐stranded RNA stretches and regions of increased conformational flexibility or distorted by the presence of bulged nucleotides. Hydrolysis of urea/EDTA‐treated E. coli 5S rRNA (B form) shows the presence of two strong helical domains; helix A retained from the A form and a helix composed of RNA regions G 33 –C 42 and G 79 –C 88 . Other RNA regions resistant to hydrolysis may be involved in alternative base pairing, causing conformational heterogeneity of that form. Pb(II)‐induced hydrolysis distinguishes two different forms of rat liver 5S rRNA; the native A form and the form obtained by renaturation of 5S rRNA in the presence of EDTA. Pb(II)‐hydrolysis data suggest that both forms are highly structured. In the latter form, the orientation of the bulged C 66 is changed with respect to helix B. At the same time, a new helical segment is possibly formed, composed of nucleotides from helix C and loop c on one side and from helix E and loop d' on the other.