Crosslinking of ribosomal protein S18 to 16 S RNA inE. coliribosomal 30 S subunits by the use of a reversible crosslinking agent:Trans-diamminedichloroplatinum(II)

Abstract

We have previously developed [(1987) Biochemistry 26, 5200–5208] the use of trans-diamminedichloroplatinum(II) to induce reversible RNA-protein crosslinks in the ribosomal 30 S subunit. Protein S18 and, to a lesser extent, proteins S13/S14, S11, S4 and S3 could be crosslinked to the 16 S rRNA. The aim of the present work was to identify the crosslinking sites of protein S18. Three sites could be detected: a major one located in region 825–858, and two others located in regions 434–500 and 233–297. This result is discussed in the light of current knowledge of the topographical localization of S18 in the 30 S subunit and of its relation with function.