In vivo X-ray footprinting of pre-30S ribosomes reveals chaperone-dependent remodeling of late assembly intermediates.

ABSTRACT: Assembly of 30S ribosomal subunits from their protein and RNA components requires extensive refolding of the 16S rRNA and is assisted by 10-20 assembly factors in bacteria. We probed the structures of 30S assembly intermediates in E. coli cells, using a synchrotron X-ray beam to generate hydroxyl radical in the cytoplasm. Widespread differences between mature and pre-30S complexes in the absence of assembly factors RbfA and RimM revealed global reorganization of RNA-protein interactions prior to maturation of the 16S rRNA and showed how RimM reduces misfolding of the 16S 3' domain during transcription in vivo. Quantitative (14)N/(15)N mass spectrometry of affinity-purified pre-30S complexes confirmed the absence of tertiary assembly proteins and showed that N-terminal acetylation of protei

SUBMITTER: Clatterbuck Soper SF 

PROVIDER: S-EPMC3840108 | biostudies-literature | 2013 Nov

REPOSITORIES: biostudies-literature