Photoinduced cross-linkage, in situ, of Escherichia coli 30S ribosomal proteins to 16S rRNA: identification of cross-linked proteins and relationships between reactivity and ribosome structure.

摘要: The kinetics of photoinduced cross-linkage Escherichia coli 30S ribosomal proteins to the 16S-rRNA molecule in intact subunit was studied this report. All become cross-linked 16S rRNA before changes sedimentation characteristics can be detected. exhibit different reactivities reaction. One group proteins-S3, S7-S9, S11, S12, and S15-S19-is by single-hit kinetics, or photoprocesses nonunity but low multiplicities. A second proteins--S1, S2, S4-S6, S10, S13, S14, S21--is a complex nature. comparison these data with other properties individual related ribosome structure indicated that most multiplicities had been classified rRNA-binding nonphotochemical methods, large as nonbinding proteins. There were certain exceptions correlations. Proteins S4 S20, both RNA-binding proteins, photoprocessses multiplicities, S3, S18, none which have exhibited could explained terms limitations inherent photochemical methods used study types RNA-protein interactions subunit. presented here also suggest labile cross-links are present uv-irradiated subunits, neither peptide-bond cleavage nor modification charged side-chain groups accompanied However, some RNA-chain breakage might occurred.