Partial reconstitution of active ribosomes and 50S subunits

Escherichia coli ribosomes and their 50S subunits disassembled by LiCl treatment can be reconstituted into structurally completed but inactive particles. However, peptidyltransferase and polyphenylalanine synthesizing activity can be partly recovered by the addition of methanol to the reconstitution system. Furthermore, entirely active ribosomes and 50S subunits are reconstituted when methanol is present during the initial treatment with LiCl to disassemble the ribosomal components. The presence of methanol (10% v/v) during this treatment diminished the release of some proteins but does not affect the separation of the 5S RNA.