Structural domains of ribosomal protein S8 and their relationship to ribosomal RNA binding

Abstract
Escherichia coli ribosomal protein S8 has been subjected to mild proteolytic digestion in order to search for structural domains within the protein [1]. A characteristic fragment produced in high yield after chymotrypsin treatment has been located with the protein sequence. Circular dichroism has shown this domain to be rich in α helix. However, the fragment loses its ability to bind to 16 S rRNA as does a similar fragment produced by trypsin cleavage. The intact protein is required for rRNA binding and is highly protected against proteolytic digestion when bound to the RNA.